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PICList Thread
'Parallax 16C64 Adapter pinout..'
1994\06\16@190829 by johnsonj

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I just bought a Parallax programmer(its much better then my old microchip
one).  Anyway i really dont have money to buy the adapter(yes i know is
only $50).  I have a couple enginnering samples of the 64 and would like
to program them.  Does anyone have this adapter and would you give me the
pinouts on it.  That is what pin on the header goes to which pin on the
16c64.  
later
       John

_____________________________________________________________________________
John Johnson                   |If it's not OS/2.|spam_OUTjohnsonjTakeThisOuTspamccwf.cc.utexas.edu
                              |It's crap!       |.....johnsonjKILLspamspam@spam@ghostwheel.bga.com
OOOO SSSS    /2222  2222    11 |                 |
O  O S      /    2     2     1 |"We need breath- |"Bite me." Tom Servo
O  O SSSS  /  2222  2222     1 |-ing room!"      |
O  O    S /   2     2    ..  1 |     Bill Gates  |"I want to decide who lives
OOOO SSSS/    2222  2222 .. 111|                 |and who dies" Crow T. Robot
-----------------------------------------------------------------------------



'...no subject...'
1994\07\14@095429 by RAM6%Proj%RnD
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Microchip will be sending 16C64 parts and tools in mid to late August. The
16C74 will be sampling in Sept-Oct with production in the 1st quarter of 95'.
Engineering samples of the 74' will be available in August (so I'm told
anyway!) I've had 64' samples for about 4 months (but no tools).

-Rodger

'is there a known trap here.'
1994\07\14@181735 by eric

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> A secondary piece of code runs fine in the simulator, but nevers runs on
> the hardware (same hardware that runs a simplier but similar program).

If you ever use indirect addressing at all, make sure you set the FSR to zero
before you initialize any other memory.  The simulator probably starts with
zero in the FSR, but the chip doesn't.  Since two bits of the FSR determine
which register bank is directly accessible, if you don't initialize it your
direct RAM accesses will be to a random bank.  Then when you set the FSR
in preparation to use IND, you will lose all your data.

Then again, you might have an entirely different problem :-)

Cheers,
Eric

1994\07\14@182301 by Gary Gaskell

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Hi,

I have a PIC16c57.

An elementary program I wrote runs fine on it.

A secondary piece of code runs fine in the simulator, but nevers runs on
the hardware (same hardware that runs a simplier but similar program).

Is there any known traps that I particularly should watch when I goto the
hardware?  I have spent the last two weekends on this problem, so any
advice would be appreciate.  I am happy to send my code to anyone that
may help solve the problem.

regards

Gary Gaskell
DSTC
Cooperative Research Centre for Distributed Systems Technology
Queensland University of Technology
Ph    +61-7-864 1051            FAX +61-7-864 1282
                               Email gaskellspamKILLspamdstc.qut.edu.au





1994\07\14@201554 by dthomas
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Pitfalls I have run into that may or may not be what you're up
against:

1. FSR in a 57 may be pointing to any register bank on startup.  The
simulator might assume bank 0 always.  Clear the FSR at the start of
all 57 code that cares about the bank switching ability.

2. I've found SLEEP to not work sometimes if it's in the second half
of a page.

3. You may have code that spills over a page boundary and uses jumps,
in which case it jumps to the wrong page.  My habit is to always
include org 0, org 100h, org 200h ... org 700h in every '57 program,
and put at least a nop at the top of each half page, so any time
anything spills over, the assembler will tell you.

4. Never compare RTCC directly with anything.  Move it to W first, or
the PIC will give erroneous results.  For instance, testing RTCC will
never set the Z bit, even though if you repeatedly move RTCC to W and
test W you'll see zero every 256 ticks.

5. Remember to reset page select registers after a call to a
subroutine not on the current page.  Otherwise, local jumps aren't ;^)

Good luck finding your problem.  I've discovered most of these by
putting checkpoints in where I flash LED's or whatever, until I figure
out what's wrong.

David

'Microchip BBS no.'
1994\07\18@072849 by b.crotaz

picon face
Scott Colson wanted the Microchip BBS no.
For anyone lse who hasn`t got it...

They are a user of Compuserve.
To find your nearest Compuserve,

Set your modem to 7E1 (7 bit, even parity, one stop)
Dial (800) 848-4480 for 300-2400 baud, or
Dial (800) 331-7166 for 9600 baud
The system will respond with
Host Name:
Type NETWORK <enter>
Follow the instructions.

Alternatively, voice info is on
(614) 457-1550

To connect to the BBS,
Set your modem to 8 bit, No parity, One stop (8N1)
Dial Compuserve
Type <enter>
A garbage string will appear
Don't panic!
Type +<enter>
Host Name: will appear
Type MCHIPBBS<enter>
You will now be connected.

I take no responsibility for the above, it came from a Microchip
data sheet.

Bryan

--
---------------------------------
BRYAN CROTAZ - .....b.crotazKILLspamspam.....ic.ac.uk
---------------------------------
TECHNICAL MANAGER
Student Television Of Imperial College
Beit Quad, Prince Consort Road
London  SW7 2BB
Tel. 071-594-8104
Fax. 071-225-2309 attn. STOIC    


'Xon/Xoff protocol in Asynchronous Serial I/O'
1994\08\01@173933 by ktor Dvorak
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Software handshaking Xon/Xoff on PIC16C84.
Do you know about some help in buffered serial protocol with Xon/Xoff ?

                                 Thanks in advance

RNDr. Viktor Dvorak
EraseMEdvorakvspam_OUTspamTakeThisOuTearn.cvut.cz
Praha
Czech Republic
Europe

1994\08\02@074839 by Derrick Early

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Hello Dr. Dvorak,

I'm a rookie at this microcontroller programming stuff, but I am very interested
in finding the answers to your questions.  Since, I have to write the same
routines for the pic16c64.

I wonder what clock speed you are using for the chip.  This may have
an effect on the number of program steps that the chip must wait for the
next bit.  You could calculate this value and set a loop parameter, so
you could generalize the code for any speed.

Also if the chip is wasting time waiting to send the next bit, you could use
that time to check for an xon (h'11') or xoff (h'13') byte to see if you should
stop sending bits.

You probably already thought of this, and remember I'm a rookie.

Yours,

Derrick Early, the rookie user

'MpK coming now...'
1994\08\11@110752 by crocontroller discussion list

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Hello folks,

there was some (good) response about my new "Multi process Kernel". So "I" will
post it now to our ftp server ftp.ntb.ch. Actually my sysop will do that
hopefully within some days. (/public/MicroChip/Pic/...)

To avoid too much questions later I've described details more precise
in the source. That4s why it lasted so long... Thanks for your patient.

There will also be 2 samples showing the usage of MpK and a simple shell
that I use. (Comes up with shareware boxer, telemate and 4DOS).
One sample (FSS) has got an ORCAD pcb design included ...
Read the *.idx files for an overview.


- Michael
                  ////
__0__           '(o o)'                                        __0__
(_____)--------ooO-(,)-Ooo-------------------------------------(_____)
| / |   Kellenberger Michael                                   | \ |
| / |   (electronics engineer,BSc)                             | \ |
| / |   Institute for integrated microsystems  ( IMS / MEMS )  | \ |
| / |   Neu Technikum Buchs     Phone: +41-81-755 34 44        | \ |
| / |   CH-9470 Buchs/SG        Fax:   +41-81-756 54 34        | \ |
|___|   Switzerland             Email: kellenbespamspam_OUTsparc1.ntb.ch  |___|
(_____)--------------------------------------------------------(_____)
  0                                                              0


BTW: MpK sounds a little bit too proud! So don't blame me afterwards...

PS:  Somewhere out in the net is an 2 week old message called "MpK coming soon".
    It is supposed to wait there in an endless loop !!?? So just delete it
    if it finaly appears somehow...

1994\08\15@141340 by crocontroller discussion list

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I did not find these directories or any information on MpK at ftp.ntb.ch.
Or any PIC info at all????   I'm very interested in MpK, so let me know if its
at another site.    Thanks a million       Steve
----------{Original Message removed}

1994\08\18@154816 by crocontroller discussion list

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>
> I did not find these directories or any information on MpK at ftp.ntb.ch.
> Or any PIC info at all????   I'm very interested in MpK, so let me know if its
> at another site.    Thanks a million       Steve

Hi Steve,

With a little search I found that the original directory is :

/MicroChip/...

and NOT /public/MicroChip/...

Hope this helps,

--
     ____________________________      __________________________________
    /                           /\    /                                 /\
   /   Argiris A. Kranidiotis _/ /\  /       E-mail (Internet):       _/ /\
  /  University Of Athens    / \/   /                                / \/
 / Informatics Department    /\    /  @spam@akraKILLspamspamzeus.di.uoa.ariadne-t.gr  /\
/___________________________/ /   /_________________________________/ /
\___________________________\/    \_________________________________\/
 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \     \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \

'Parallax or Picstart? (also, uASM note)'
1994\08\31@230011 by eric

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> Additionally, the PicStart's serial connection is completely
> nonstandard/proprietary, with pretty low-level UART stuff. Would this still
> work with LINUX (even emulating DOS)? It definitely doesn't work with the
> MAC.

I've been looking at the PICStart communications with an HP 4952A protocol
analyzer.  They use receive data, transmit data, and one handshake line in
each direction.  The handshake lines are toggled after every command or data
byte.

I haven't completely worked out the details yet, but I think the Macintosh
could actually talk to it.  A special cable might be needed.

Cheers,
Eric


'Parallax or Picstart? (also, uASM note)'
1994\09\01@010100 by crocontroller discussion list
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>Hi PICers,
>
>David said,
>
>>
>> 1. Parallax uses parallel PC port, PICSTART uses serial.  You could
>> probably use PICSTART from Linux with the DOS emulator, but you can't
>> do that with the parallax since the DOS emulator doesn't support the
>> parallel port.
>
>I know this list is not for Linux discussions, but I must disagree here.
>The parallel port works fine under DOSEMU. Add the following line to your
>/etc/dosemu.conf


Additionally, the PicStart's serial connection is completely
nonstandard/proprietary, with pretty low-level UART stuff. Would this still
work with LINUX (even emulating DOS)? It definitely doesn't work with the
MAC.

Again, I'll take this time to second Don Lekei's recommendation of the
Beradine MicroBurner 512 (see FAQ for more info). It is a little pricey
(maybe $350), but well worth it. I have both this and a PICSTART (which I
used before I found the microburner), and I don't even take the PICSTART
out of the box anymore. It uses a standard RS-232 serial connection, and
you can get new modules to let it program new/different chipsets (although
they are also admittedly a bit pricey at somewhat over $100 each). It also
uses a serial programming routine (WRT THE PIC), so I always have 5 wire
connectors on my oceanographic instrumnts, and I can update the frmware
with a simple 5-wire cable from the Microburner to the instrument's circuit
board (ie: in situ programming, whic I believe the Parallax TruFlight will
also do, but the PICSTART will not). Also, since you can download programs
from the host computer, to the microburner (which can run off the included
AC adapter or a 12V battery) you can program the new firmware into the
buner, and take it (no host computer) to the instrument and update the
firmware.

I have no cnoonction to the MicroBurner, except as a normal customer.

-jory

PS: Has anyone gotten a version the uASM (for the MAC, from MicroDialects)
that will work with the 16c84? Any work on any new MAC-based development
tools (I'd especially like a good c84 supporting simulator) I am really
trying to get away from SOFTPC! (and I don't have a UNIX or PC/LINUX box,
so those emerging avenues/alternatives don't help.  :)

Gratuitous Background Info:I thought I had bought a c84/c71 uASM version,
but hadn't gotten around to using it for a long time. When I recently tried
assembling some c84 code with it, I found it wouldn't recognize page1
memory access, etc. I didn't see anywhere I could select the PIC version,
so I guessed I had the wrong version. I called MicroDialects, but could not
get a hold of anyone who could answer my questions. Several weeks ago, I
finally returned the original disk, with a polite letter asking for the
correct version (I have not heard back yet). Anyone else have ay particular
experiences with them?

1994\09\01@020540 by crocontroller discussion list

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> Additionally, the PicStart's serial connection is completely
> nonstandard/proprietary, with pretty low-level UART stuff. Would this still
> work with LINUX (even emulating DOS)? It definitely doesn't work with the
> MAC.

I've been looking at the PICStart communications with an HP 4952A protocol
analyzer.  They use receive data, transmit data, and one handshake line in
each direction.  The handshake lines are toggled after every command or data
byte.

I haven't completely worked out the details yet, but I think the Macintosh
could actually talk to it.  A special cable might be needed.

Cheers,
Eric

'ANOTHER PROGRAMMER (Was Re: Parallax or Picstart?)'
1994\09\01@215433 by -Kellogg High School

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I have the PGM16 from Advanced Transdata Corporation.  Having never seen
a picstart or paralax programmer, it might be an OEM or clone of one of
them, but in my sample of 2 parallel ports to connect it to (clone
DX-2/66 and Zeos sub-notebook) it runs great.

I regularly travel with the Zeos & programmer.  Very convenient.  Their
real time ICE also runs well on the Contenda - I can't imagine tucking my
desktop system in the back seat of the plane to take my development
system on the road.  AS it is, an old briefcase serves as a complete real
time ICE / programmer capable system.

If anyone knows if this PGM16 critter is a clone of one of the other
programmers please let me know.

/s/ Bill

'Need PIC Object Code (Electronics Now Wand)'
1994\09\19@144010 by crocontroller discussion list

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Don Lekei prophesized:
> I have
> been toying with some Parallax-to-ASPIC macros, but I have little
> confidence in them yet as I do not know the actual  code generated by the
> Parallax "Instructions".

The Parallax User's manual shows the native instructions generated for
each Parallax mnemonic.  I could also assemble the assembler test file
(ie. all mneumonics) and send you the hex version.


'Detection of why RESET occurred? - Similar note...'
1994\11\10@005400 by crocontroller discussion list
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> It will work -- the catch is that you use an RC on the reset pin.  The
> keypress wakeup app note that someone else alluded to is the right
> approach.

< stuff deleted >

I've got a SIMILAR type of question.....  The databook says that when
powering up a PIC, Vdd must start from 0V.  I've found this, unfortunately
to be correct.  Is there any way that you guys can think of to implement
an inexpensive circuit to bring the power to 0V QUICKLY after power is
disconnected so that you can QUICKLY power back up instead of waiting for
the PIC to drain your power supply caps?

--

           -- Paul Greenwood --  (KILLspampabloKILLspamspamaustin.ibm.com)

Any small object that is accidentally dropped will hide under a
larger object.

'Pure Unobtanium'
1994\11\15@074608 by crocontroller discussion list

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>|> I have no affiliation with PU other than a past customer and acquaintance
>|> of Ed Nisley - I do *not* get a kick-back from this. However, if you do
>|> call because of this posting, please mention my name, since I am doing this
>|> as a favor to him.  Thanx.
>
>Mr. Radford,
>You did not put a phone number or address in your post.

Sorry - I did the same thing in my newsgroup post and had to post a followup
there too...

The address/phone number are:

   Pure Unobtanium - your unusual parts source
   13109 Old Creedmoor Road, Raleigh, NC 27613-7421
   FAX/voice: (919) 676-4525
   Compuserve: 74065,1363

> It seems a shame that Mr. Nisley needs to close shop.  I haven't ever heard
> of this company before.  Perhaps a more frequent mention of his services
> on the net by satisfied customers like yourself could have helped avert this.

Yes, it really is a shame. Some of the items I buy from him are either very
difficult, or even impossible, to get in small quantities at *any* price.
Basically, Ed told me that the problem is as soon as a part gets a market,
and no longer is 'pure unobtanium' material, a large distributor like Digikey
will start selling the parts, undercutting him so much that he can't even
move the inventory he already has. So basically, he makes a few dollars on the
first few sold, and then looses money on the last few, and basically breaks
even after handling all the paper work, inventory maintenance, packaging, etc.

> Oh well, thanks for posting about the sale.

Sure thing. Since there has been other interest, I'll include the small
list I made to comp.robotics and sci.electronics here for you to see
other parts being carried by him:

-----------------------------------------------------------------------------
I just received my Pure Unobtanium flyer today and prices have been
reduced drastically for a going out of business sale. For those not
familiar with PU, it is a small company operated by Ed Nisley who
writes the Firmware Furnace column for Circuit Cellar Ink's Computer
Applications Journal (CCI/CAJ). PU typically carries parts that are
difficult (or impossible) to obtain in low quantities - perfect the
hobbiest types.

Ed said he was closing down the business since it was just too much
work for the small financial return.  I think he only sent the flyer
out to those individuals that have actually ordered parts from him, or
contacted him in the last few months for a catalog.

Since everyone on these two newsgroups may not get the catalog, I've
included some of the best robotics/hobbiest type parts here:

  UCN5804B - unipolar stepper driver 50v, 1.25A ........  $2.60
  UDN2993 - dual H bridge, 40v, .6A ....................  $2.70
  UDN2998W - dual H bridge, 50v, 2A ....................  $5.50
  PCF8574 - 8bit I2C I/O expander ......................  $3.20
  PCF8583 - I2C clock, with 240 bytes RAM ..............  $7.10
  TDA8444 - I2C octal 6bit DAC .........................  $5.00
  Chip sack 8031 (everything for a basic 8031 system) ..  $6.00
  87c751 - EPROM part .................................. $18.00
  GP1U52Y - 40khz IR receiver ..........................  $1.90
  MT8808 - 8x8 crosspoint switch .......................  $6.20
  MAX233 - 5v RS232 interface ..........................  $5.00
  MAX7219 - Serial LED driver (drives 64 LEDs) .........  $5.50
  Power opamp (3.5A, +/-3v to +/-13v) ..................  $1.60
  UDN2585 - 8bit source (25v, 120mA) ...................  $1.50
  MAX691 - uP supervisory circuit ......................  $4.50
  MT8888 - DTMF transceiver ............................  $4.00
  SSI75T204 - DTMF receiver ............................  $4.90
  DS1232 - watchdog, PS monitor, reset debounce ........  $2.50

and many more (6 full pages with descriptions).

I have no affiliation with PU other than a past customer and acquaintance
of Ed Nisley - I do *not* get a kick-back from this. However, if you do
call because of this posting, please mention my name, since I am doing this
as a favor to him.  Thanx.

-----------------------------------------------------------------------------
Rodney Radford,     Senior Systems Developer,  Image Technology Group
RemoveMEsasrerTakeThisOuTspamunx.sas.com  SAS Institute, Inc, Cary, NC 27513  (919) 677-8000 x7703
-----------------------------------------------------------------------------

'Parallax and OS/2: partial success, but no cigar'
1994\11\16@003507 by crocontroller discussion list

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I talked with Parallax tech support about my OS/2 problems.  Not too
surprisingly,  they didn't have an answer.  However,  I told them about the
"introductory special" on the new version of OS/2 that's on now,  and the
guy I was talking with sounded like he might go buy a copy to play with
(they don't have it in-house at all),  so maybe they'll have a little expertise
soon.

After doing a little fiddling with the session parameters to allow more direct
access to the PC hardware,  I got PSIM talking with the ClearView 5X under
OS/2.  Sort of:  it still comes up with comm errors,  and needs to be told to
retry almost every command,  but it's a start...

I took a peek at what was happening on the serial interface while all this
was going on.  It looks to me like there's still a little timing dependence in
the software,  but that the basic protocol for the PC-to-emulator interface
could be ported to other platforms (like linux,  or even the Mac) with only
minor tweaking.  I doubt they'll do much about that anytime soon (I think
the slippages in shipping new products are a sign they're overloaded),  but
the occasional nudge from those of us who prefer not to do DOS may keep
them moving in the right direction.

Ran


'No Subject'
1994\12\22@131204 by Alex
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picon face
In article: <spamBeGone9412050955.aa08811spamBeGonespampunt.demon.co.uk> TakeThisOuTalasdairEraseMEspamspam_OUTaifh.ed.ac.uk writes:
>
> >     Has anyone out there tried or had success implementing
> >    fuzzy logic on a PIC 17c42?  Also, does Michrochip or any
> >    third party supplier have HW/SW/tools to support fuzzy
> >    logic development for PIC microcontrollers? I'd appreciate
> >    any info/help anyone could give me in this regard.
> >       Thanks,
> >       Roy Walker
> >
> I don't know much about it but Microchip got some software house in
> Germany, whose name I have forgotten, to write a 'Fuzzy Logic

The software house is Inform GmbH in Aachen, who have written fuzzy
logic tools for a wide variety of different microcontrollers, including
(now) the PIC.

> Development Tool' called 'fuzzyTECH'. Since it's effectively a third
> party tool like the MPC Compiler you can expect to pay a similar price.
> There is supposed to be an 'Explorer Edition' of the software which has
> been crippled to limit designs to 2 inputs, 1 output and 1 rule block
> which may be a more reasonable price but I don't know how much
exactly.

AFAIK, prices (for a limited intro period) are $795 for the full
kit and $195 for the Explorer kit.

> I attended a PIC seminar last month, run by one of Microchip's
> distributors in the UK,

Thank you - hope you enjoyed it!

> where I was told that there were going to be a
> series of Fuzzy Logic seminars which would cost around L500 and would
> include the 'Explorer Edition' of fuzzyTECH plus the temperature control
> demonstration board.

These did indeed occur in the UK, run jointly by Polar Electronics and
Microchip. 3 days/27 people - nearly killed me! :-(
Fuzzy seminars have also been run in Germany, by the Microchip
distis/direct FAEs there - I assume (tho' I'm not sure) that the
distsi/direct FAEs in the US and other regions will do or are already
doing this too.

> Whether the software will run on a 17c42 or not I
> wouldn't like to say. Since it is an 'official' Microchip product you
> should be able to find out anything else you need to know from them.

The software will produce MPASM-compatible assembler code for all of
the PICs, inc. the 17C42.

If there is sufficient interest out there, I will try to put together
some sort of a FAQ on fuzzy for this mailing list - any takers?

B.rgds

Alex R. Baker - Field Apps Engineer Ph: +44 628 851077  Car: +44 831 494921
Arizona Microchip Technology        Fx: +44 628 850259  Email: RemoveMEalexspamTakeThisOuTmicrochp.dem
on.co.uk
ANY VIEWS EXPRESSED HERE ARE MINE AND DO NOT NECESSARILY REPRESENT THOSE OF MY E
MPLOYER


'Another Intro'
1995\01\26@123710 by Errington A
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Hi

Since we are all introducing ourselves I would like to say hello.  I
subscribed to the list last week, and although it went a bit quiet I am
interested in what is going back and forth now.

My name is Andrew Errington and I work as a PC consultant at Lancaster
University (UK).  My interest in PICs came about after building a project
with a BASIC Stamp last year and deciding I could do more if I controlled
the processor directly.  I bought Microchip's Embedded Control Handbook,
which is _full_ of cool ideas, and I built the 16C84 development programmer
detailed in there.  I modified David Tait's controller software so I now
have a development environment that cost me about ?20 (or $30).

The PIC84 is excellent for development as it's EEPROM memory allows you to
recode and reprogram with no effort.  I have a project underway (in my spare
time (ha ha!)), and I will probably be looking at the other PIC's with extra
features for later projects.

[This is my third attempt at getting something onto the list.  I hope that
the other two are not marauding somewhere else...]

Andrew M. Errington
PC Consultant
Lancaster University
a.erringtonEraseMEspam.....lancaster.ac.uk
Tel: +44 1524 592678
Fax: +44 1524 844011

1995\01\26@133854 by Pic User

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face
Hi my Name is James Kelly. I work in computer services for the University
of Kansas. I am an Old timmer with Robotics (since 81) and of all the
things I've seen come and go the PIC has contributed a good balance to
help bring the next generation of Robotics in to the 90's.

 Hi to all you fine folks. Looking forward to Learning with you all.
James K.
"Wisdom is more valuable than Gold or Silver."

'Another PIC user introduction'
1995\01\26@184928 by Tracy R. Reed

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On Thu, 26 Jan 1995, Paul Haas wrote:

> For your entertainment the hottub is at:
>   http://hamjudo.com/cgi-bin/hottub
> The refrigerator is at:
>   http://hamjudo.com/cgi-bin/refrigerator

Hahahahahahahaha!!!! That's great! Sorry to hear about the rubber duckie,
I know it must have been quite a blow. What a gratuitous use of
electronics. :) Perhaps I will be able to set up something like this
someday. Your setup ranks right up there with the coke machine at MIT and
the coffee pot in some guys office at some place I cannot remember at the
moment. I'm gonna add a link to your appliances from my homepage. :)
There's only one thing missing...a camera on the hottub to show us what
(or who) is going on there! :)

1995\01\26@185756 by Robert Dale Bourque

picon face
Hello everone,

My name is Robert Bourque, and I am a senior EE student at the
University of Maryland.  My introduction to PIC's was through my
senior project, which is to design a 50 MHz digital scope.
We (there are 5 in the group) used a PIC for the PC-scope communication
and to setup the various components on the board prior to each
memory-capture period (which is controlled by a MACH).

My main responsibility in the project has been the PIC programming,
as well as some of the CAD layout.

I have co-op'ed with General Dynamics and also with TeleDanmark, the
Danish telecomm.  I am now taking my last class at night, and finishing
the scope project in my spare time.  I still have my student job on
campus (office gopher) but am really interested in finding a full-time
engineering job doing hardware/software related to realtime control, etc.

I am quite interested in the robotics applications of PIC's too.

1995\01\31@130633 by holster

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face
I tried sending this last week, but it didn't get out.

----------------------------------------------------------------------------

Gee, I guess there was somebody home after all!  Now to let you know who
I am.

My name is Dan Houlton.  I got my BA in CS from UofM a little over a year
ago and have since been working as a Software Engineer for General Dynamics
in the Detroit, MI area.  Some of my interests are motorcycling and flying RC
airplanes.  I've only recently become aware of PIC controllers and thought
it would be pretty fun to play around with, and since I like flying (not
repairing) RC, I thought I'd tinker with a wing leveler or autopilot.  It
seems to be a pretty tall order though, the more I research it.  The basic
idea is to use a PIC, a gyro (probably from a model helicopter), and maybe
an altimiter to control attitude and (maybe) altitude.

I got copies of Microchip's Data and Embedded Controller Handbooks to help
me decide what to use and was thinking of getting the PICStart package they
have.  I know Motorola 68030 assembly and I'm sure I could pic up PIC, but
I'm a C programmer at heart, so if anybody knows of any good cross compilers,
please let me know.

I think I'll get the the book "The PIC Source Book" mentioned in the FAQ, but
I'd really like to get "A Beginners Guide to the Microchip PIC".   This is
the one printed in the UK, and I haven't been able to find it here in the US.

So that's me.  I noticed some others were dealing with RC as well.  If any-
one has any advice about what to use, how to use it, or where to look for
more info please let me know.  I'd really like some US sources for the book
I mentioned above.  Who knows?  I might actually get to the point where I'm
saving more airplanes than I crash (that's a nasty habit of mine 8-(  ).


--Dan

'PIC FAQ Announcement [repost]'
1995\01\31@204552 by tom

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picon face
Re-posted due to listserver rejection. <sniff>
To all PIC users,

The PIC FAQ has been approved for posting to the *.answers hierarchy.
[cue fanfares, fireworks and celebrations]:)
In the very near future (the weekend) it will be posted to the following
newsgroups:
       sci.electronics
       sci.electronics.repair
       comp.robotics
       comp.realtime
       sci.answers
       comp.answers
       news.answers

This means that it will be archived for posterity at

       rtfm.mit.edu :  <plus all mirror sites>
       /pub/usenet/comp.answers/microcontroller-faq/PIC
       /pub/usenet/sci.answers/microcontroller-faq/PIC
       /pub/usenet/news.answers/microcontroller-faq/PIC

The schedule for updating will be monthly, unless I run out of stuff to add.
Normally, I'll post to the list about a week before the newsgroups to give you
first chance to give me feedback.

I've added * * A New Section * *
This will contain useful code snippets and routines. Send them in !
[otherwise I'll have to steal them :) Hi, Andrew :) ]

Please take the time to scan the FAQ for innaccuracies, omissions or cock-ups.
YOU may have a piece of vital information, that the other readers may be
desperate for !

IMPORTANT !   Do you think that the FAQ is in danger of becoming "too
commercial" ? Opinions please.

I *may* in future, post the FAQ to the PICLIST in uucoded / zipped format
to save bandwidth, unless there are any objections ?????
Well, are there ???
Speak up or be ignored, the choice is yours.
:) I feel like a game-show host :) Come on down !

[sorry, the excitement has gone to my head, normal lurking will be resumed
ASAP.]

Replies _either_ to the PICLIST _OR_ to

<EraseMEtomspamtakdsign.demon.co.uk>
__
  TAK


'Minolta Camera Interfacing ...'
1995\03\02@161401 by Christer Johansson
picon face
>I have a Minolta 7000i camera. I would like to interface my camera to a
>computer via RS232 link. The camera has a slot for expansion cards and I need
>to know how this interface works. I assume they use some sort of serial
>communication (maybe I2C). Does anyone of you know how to get more details
>regarding this interface? or maybe already HAS the information?

Hi Conny,

Try to call Philips and ask for the IC12a and IC12b databooks. Lots
of I2C info and datasheets...

/Christer

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
* Christer Johansson --  HTH  -- * email: RemoveMEcjEraseMEspamEraseMEaristotle.algonet.se *
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
   >> World Wide Web: http://www.algonet.se/~cj/homepage.html <<
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

'No-assemble code'
1995\03\21@185217 by James L. Johnson

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face
Hi again,

 Here's a real live example of Microchip code that won't assemble in
the Parallax PASM and I don't know why.  The error I get is in the
first line of the "test program".  The error says:

 "data was already entered at 000h"   and the line that generated it is:

 "main  movlw   0F3h"


 So ... what data was already entered?  There is no mention of a location
000h in the first place.  Perhaps this is one of those instances where
the assembler is totally confused by something else, but prints that as
the error.  You know how these software things are.

 Any ideas?

 Tnx,

 Jim Johnson
 RemoveMEjjohnsonspam_OUTspamKILLspamhpl.hp.com



;*******************************************************************
;        include "mpreg.h"

       include 'dbl_add.asm'   ; JJ - attempt at including a file
       include 'dbl_jj.asm'    ; JJ - another include file

;       org     0
;
LupCnt  equ     10             ; Number of iterations
;
SqrtLo  equ     10             ;ACCaLO
SqrtHi  equ     11             ;ACCaHI
;
NumLo   equ     1Dh
NumHi   equ     1Eh
count   equ     1Fh
;
;
init
       movlw   LupCnt
       movwf   count
       movf    NumHi,W
       movwf   SqrtHi
       movf    NumLo,W         ; set initial guess root = NUM/2
       movwf   SqrtLo
       bcf     STATUS,CARRY
       rrf     SqrtHi
       rrf     SqrtLo
       retlw   0
;
div2    bcf     STATUS,CARRY
       rrf     13,W        ;ACCbHI
       movwf   SqrtHi
       rrf     12,W        ;ACCbLO
       movwf   SqrtLo
       retlw   0
;
Sqrt    call    init
sloop   movf    NumLo,W
       movwf   12          ;ACCbLO
       movf    NumHi,W
       movwf   13           ;ACCbHI
;
       call    D_divS          ; double precision division
       call    D_add           ; double precision addition
;                               ; the above 2 routines are listed
;                               ; as seperate routines
       call    div2
       decfsz  count
       goto    sloop
       goto    over            ; all iterations done
;                               ; branch back to desired location
;
;*************************************************************
;               Test Program
;*************************************************************
;
main  movlw   0F3h
       movwf   NumHi
       movlw   0F6h       ; Set input test number = 62454
       movwf   NumLo     ;  = F3F6h
;
       goto    Sqrt      ; cannot use CALL : Math routines
;                         ; use up all the stack.
over    nop               ; all iterations done
;
self  goto    self      ; result = 00F9h = 249
;                         ; exact sqrt(62454) = 249.9
;
       org     0
       goto    main
;
       END

1995\03\22@034410 by Chuck McManis

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Jim, your specific problem is this:

At the beginning of your code it starts out:

>> init
>>         movlw   LupCnt
>>         movwf   count
>> ...

Now you've commented out the org 0 so that was ignored, however
in the absence of any directive the assembler starts loading code
at location 0. (makes sense yes?)

Now later in your program you have:

>>;
>>        org     0
>>        goto    main
>>;
>>        END

Which re-sets the program counter to zero and trys to assemble the
'goto main' into that address. Which overwrites the 'movlw LupCnt'
that you had in init above.

The correct fix for this specific problem is that you should move
the 'goto main' to be the first statement in your program and then
it will assemble at location 0 and all will be well.

I both agree and disagree with what has been said about Parallax's
assembler. On the one hand, if you've got working MPASM code it can
be a real pain to get it to assemble correctly with the Parallax
assembler. On the other hand, if you learn the Parallax assemblers
quirks early on (and MPASM has its own) then writing new code from
scratch can be fairly easy in both.

The lack of a macro facility and conditional assembly in the Parallax
assembler hurt it, however if you are using Linux then you could always
run cpp over the code before feeding it to pasm.

--Chuck McManis                      All opinions in this message/article are
Sun Microsystems Inc.                those of the author, who may or may not
Internet: RemoveMEcmcmanisTakeThisOuTspamspamEng.sun.COM       be who you think it is.
Crypto-puzzle: *0U0JPFPrWRN9PkWRKeP5WRmIR9wP5QAWuIQP9Pu9tnIZ7AD1SIS

'No messages for more than a week'
1995\03\25@105727 by METMKALLEND

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face
I have received no PIC digests for more than a week now.  ARe you
all on vacation, or is something wrong with the listserver?

I guess an e-mail answer would be best, since I'm not getting the list.
Address is EraseMEMETMKALLENDspamspamspamBeGoneMINNA.IIT.EDU

Thanks.


jk

'RESOURCE: Web interface now available'
1995\03\27@105119 by Kyler B Laird

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Since I want to be able to read this list easily, it's now
archived at
  http://pasture.ecn.purdue.edu/~laird/MLists/
(select mailing list "PIC").

If you want to reply to messages through the Web interface
using my site as the mailer, e-mail me for authorization.

My thanks to Aaron Wohl <aw0g+@andrew.cmu.edu> who pointed
me to this list (but didn't give me the name for it!).

--kyler


'Don and his Oft-Ignored "Bypass" Advice (was: "My '
1995\04\06@001330 by Andrew Warren
face
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Don Lekei (RemoveME72677.2623KILLspamspamcompuserve.com) wrote:

>It seems to be a common problem to not provide sufficient bypassing on
>PIC's because they "use negligable current". There are two effects that
>happen when you under-bypass a part like the PIC because they are CMOS
> .... etc.

Don:

Do you think it's possible to make a full-time career out of advising
people to use bypass caps?  You have a pretty good start...

-Andy


--
Andrew Warren - fastfwdSTOPspamspamspam_OUTix.netcom.com
Fast Forward Engineering, Vista, California


'Yet another PIC programmer'
1995\05\01@153250 by David Tait
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A reference to interest UK hobbyists:

Robin Abbott, "PIC Programmer", Electronics Today International,
Vol 24, No. 6, pp 52-56, June 1995.

This article (to be continued next month) describes a simple PIC
programmer which connects to the serial port of a PC.  It uses two
voltage regulators, three transistors, a MAX232 and a pre-programmed
16C57 to provide a programmer capable of programming the PIC16C54, 55,
56, 57, 58 and any serial mode PIC including the PIC16C64, 71, 74 and
84.  The serial mode devices may also be programmed in-circuit using a
4-wire interface.  Cost: UKP 35 (around $55) including software. The
PCB pattern is reproduced 1-1 in the mag.

I guess ETI should be available in the USA.  If you can't find it
contact:

Wise Owl Worldwide Publications,
4314 West 238th Street,
Torrance,
CA 90505.

Tel: (310) 375 6258
Fax: (310) 375 0548

David
--
spamBeGonedavid.taitSTOPspamspamEraseMEman.ac.uk

'Nitinol wire'
1995\05\06@042759 by William Chops Westfield

face picon face
           I am looking for more sources for nitinol wire (the
   wire that contracts when you put current through it).  Currently my
   source is Mondotronics.  Does anyone out there know of any other
   sources.  Mondotronics is pretty expensive.

Dynalloy Inc
18662 MacArthur Blvd, Suite #103
Irvine CA 92715.
714-476-1206

Prices start at $10/meter, and go down to $7.50/meter for 11 meters or more,
$5.50 for 100 meters or more, and $4/meter for 1000 meters or more.

This information is several years old.

BillW

'Brian Boles, Commercial (Oh, NO!) Vendor (Gasp!)'
1995\05\13@044414 by Mark G. Forbes

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face
>From:    Brian Boles -- Applications <KILLspambbolesspamBeGonespamMICROCHIP.COM>
>Subject: Is a moderator listening?
>
>Hello from Microchip!  As the commercial vendor of the stuff this
>list concerns, I would like to ask your permission to make some
>postings to this list.  Please respond to EraseMEbbolesspamEraseMEmicrochip.com

Well, *I'm* pretty moderate at times. I think you should post away
with abandon! It'd be nice if you didn't flood the list with
marketing BS, since we all pretty much know that stuff already. Full
text of every magazine ad you're running, etc, is Right Out.

Technical discussion, new product announcements, responses to bug
reports, general state of the business, etc, would all be welcome.
Tom Mornini from Parallax is here, as are a number of other
commercial vendors. After all, quite a bunch of us here are using
these things to create products, make money and become good little
capitalists. :-)

If you wanted to talk about EEPROMs, weird little battery chips,
Basic Stamps or anything else small-system-related, we're the sorts
who'd enjoy it.

We don't have a moderator; Jory Bell maintains the list, but any
old bozo can post to it. And there *have* been a few.....
@spam@forbesm@spam@spamspam_OUTpeak.org
Mark G. Forbes
"Never ascribe to malice that which can be blamed on the engineer."

1995\05\15@122621 by Rod Rebello -- CAD Group

picon face
Brian's main intention is to post job openings at Microchip in his group.
He would like to know if this is ok with the readers of this list.
Obviously, this list is a good source of PIC-literate engineers :-).

- Rod

--
Rod Rebello
spamBeGonerrebellospamKILLspammicrochip.com
Microchip Technology Incorporated, Chandler, AZ

'App note 589'
1995\05\31@092225 by Patrick C Leger

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face
Greeting PIC users...

I just finished building the 16C84 programmer described in application
note 589, and I'm now kludging together some software to make it work.
Right now, I'm using parts of David Tait's program for his own
hardware as well as the source code for AN589, since the AN589 code is
just for communicating with the PIC and doesn't provide a front end
for reading hex files from disk and loading them into the PIC.  Does
anyone have a canned DOS program for loading hex files into the PIC
using the AN589 hardware?  The program I've kludged together is
somewhat messy...


Chris

--
Chris Leger (.....blahspam_OUTspamcmu.edu)
Carnegie Mellon University
Field Robotics Center


'App note 589'
1995\06\01@091024 by Errington A
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face
Hi Chris,

I wrote a VB DOS and VB Windows program to control the AN589 programmer,
using portions of David Tait's code.

The Windows version my be downloaded from my PIC web page at

http://www.lancs.ac.uk/people/cpaame/pic/pic.htm

If you really want the VBDOS program then I can hunt it out and mail it to
you.

Andrew Errington
Lancaster University
(TakeThisOuTa.errington.....spamTakeThisOuTlancaster.ac.uk)
----------
{Quote hidden}

'Another IRDA source'
1995\06\21@134408 by Doug Smith

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face
Another possible way to do IRDA is with the CS8130 chip from Crystal
Simicondutor.  They faxed over specs and sent a data book and it looks
pretty good.  The chip will do IRDA and a few other IR protocols.  There
is an evaluation board available but I haven't ordered mine yet.  I'll
let you know more about it after I get one to play with.  Here is the
contact person who sent me the information...

>   Brent Wilson
>   Infrared Applications Engineer
>   Crystal Semiconductor Corp.
>   email: .....bwwspamRemoveMEcrystal.cirrus.com
>   Tel: 512 912 3554
>   Fax: 512 445 2831
>   t/f: 800 888 5016 ext 3554

--
Doug Smith, SGA * Loves Park, IL * dougs%RemoveMEsgaspamspamBeGonewheaton.wheaton.edu
AppleLink: G0231 * CompuServe: 72727,3532

'Noise generator'
1995\06\21@155155 by Henry Carl Ott

picon face
>Hi
>
>I'm trying to design a digital noise generator. Horowitz and Hill have one
>based on a MM5437 which seems to be no longer available. However, I seem to
>recollect that someone has produced a solution based on a PIC. Can anyone
>enlighten me ??
>
>TIA
>
>Nick
>
>
There was an application note on the Parallax site that did just this.
Seems like overkill to use a pic just as a pseudo white noise generator, but
if you can't find the MM5437 then I guess it migh be the most economical.
I'm going to email you the source to keep the list traffic down.
Hope this helps.
later....carl

----------------------------------------
Henry Carl Ott      N2RVQ
spamBeGonecarlott@spam@spamspam_OUTinterport.net, TakeThisOuTcarlspamspampipeline.com
http://www.interport.net/~carlott/
----------------------------------------

'Non-Volatile RAM for I2C.'
1995\06\22@180132 by Clyde Smith-Stubbs

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> I need non-volatile RAM for a PIC based design.  Because of size restraints I
> would prefer it interfaced on the I2C bus.  Also, the RAM will be used to stor
e
> individual parameters, requiring modifying single locations.

I don't know of any non-volatile RAM with I2C interface, but Philips Semiconduct
ors
have several I2C interfaced EEPROM devices. This should do the job for you, prov
iding
you don't want more than about 512 bytes.

Clyde


--
Clyde Smith-Stubbs       | HI-TECH Software,       | Voice: +61 7 300 5011
clydeEraseMEspamhitech.com.au      | P.O. Box 103, Alderley, | Fax:   +61 7 300 5246
                         | QLD, 4051, AUSTRALIA.   | BBS:   +61 7 300 5235
                   HI-TECH C: Compiling the real world...

1995\06\23@015829 by

flavicon
face
> I need non-volatile RAM for a PIC based design.  Because of size restraints I
> would prefer it interfaced on the I2C bus.  Also, the RAM will be used to stor
e
> individual parameters, requiring modifying single locations.
>
> Does anybody know of companies that have such a product?

Usually you would use some serial EEPROM (or the 16c84). However, if
it must be RAM for some reason, you might want to try the 24KF04
by National Semiconductor.
This is a ferroelectric RAM, serially interfaced (like 24x04 of
other companies).

Mike

--
Dipl.-Ing. Michael Hermann   RemoveMEmchEraseMEspamspam_OUTregent.e-technik.tu-muenchen.de
Lehrstuhl fuer Rechnergestuetztes Entwerfen,     Postfach 202420
Technische Universitaet Muenchen                    089/21053651

'Noise generator'
1995\06\23@055159 by Siegfried Grob

flavicon
face
>Hi
>
>I'm trying to design a digital noise generator. Horowitz and Hill have one
>based on a MM5437 which seems to be no longer available. However, I seem to
>recollect that someone has produced a solution based on a PIC. Can anyone
>enlighten me ??
>
>TIA
>
>Nick
>
>

Some days ago, there appeared the following contribution to the piclist.
It describes generating pseudo noise with a PIC - see below.

As Henry Carl Ott stated earlier, it seems to be some overkill to use a PIC for
that simple algorithm. You can build up such a noise generator with some
shift registers, exor-gates and an additional or-gate, too:
Take a 16bit shift-register (or a chain of two 8bit-ters), serial in, parallel
out, connect adequate register bits to exor-gates (this is equal to
calculating the parity) and use the output (=parity) as the new input for
the shift regs. Clock the shift reg. at the desired frequency (well above
20 kHz for 'acoustic white' noise). Use one of the shift register bits as the
white noise output. If the content of the shift reg. is 00000000 00000000, then
no noise will be generated. So add an OR-gate between shift input and exor
output, to be able to start the noise generator.

Now the old message:
=========================================================================
Date:         Fri, 2 Jun 1995 03:07:34 +0600
From:         Mike Keitz <@spam@mkeitzRemoveMEspamEraseMEBEV.NET>
Subject:      Re: Microchip - Shift-Registers - Suggestion

[deleted]

Here's my first crack at a chip generator, with speed as the only priority.
This should make a lot of noise on Port B, using the standard {17,14} sequence.

; Spread Spectrum sequence generator.
;  Implements a 17-stage shift register with feedback from the 14th and 17th
;  stages.  8 bits of the shift register are output to port B, which must be set
;  as all output.  Any one pin of Port B will output the PN sequence.

start
       movlw   0
       tris    PORT_B          ;Make B all output.
       movlw   1               ;Constant used since C is bit 0 of status reg.
       movwf   srgl            ;If SR contains all 0's, generator will jam.
pnlp
       rlf     srgl,1
       rlf     PORT_B,1
       btfsc   PORT_B,6        ;14th bit.  If it is 1,
       xorwf   srgl,1          ;invert the new bit.
       goto    pnlp

This takes 6 cycles per chip, so it should belt out 833.333 Kchips/sec with
a 20 MHz clock.  I think there may be a way to re-write it to 5 instructions
per chip, but I'll leave that for someone else.  Considering that three
discrete IC's costing about $0.50 could do the same job at 50 MHz, it is not
a very good application for a PIC.  But the concept is there anyway.  The
PIC is fast and smart.  Discrete logic, FPGAs, etc. are VERY fast but dumb.
Making spread spectrum chips is a "dumb" process.

[...]

Disclaimer:  All code examples are untested and may contain minor or major
bugs.  Use this information at your own risk.  I do NOT work for Microchip
or have any association with them other than as a customer.

-Mike
=========================================================================

'Non-Volatile RAM for I2C.'
1995\06\23@081603 by Jaroslaw Lis

flavicon
face
> I need non-volatile RAM for a PIC based design.  Because of size restraints I
> would prefer it interfaced on the I2C bus.  Also, the RAM will be used to
store
> individual parameters, requiring modifying single locations.
>
> Does anybody know of companies that have such a product?

If you can stand EEPROM rather than pure RAM, Microchip also manufactures
them, check their www. Other are Xicor and Phillips.
They behave as normal RAM - you can write single byte to them,then  read.
They are probably a bit slow on writing (I2C acknowledgement is used
to slow master down), and number of writes is limited to about 10mln per
any byte.


Jarek.

1995\06\23@122617 by Doug Sellner

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face
Re: EEPROM Endurance.

MicroChip specs only guarntee 100K  write cycles (under normal
temperature),  wouldn't want to use these for simple index variables.

{Quote hidden}

Doug Sellner
Beach Tech
4131 Vincent Avenue South
Minneapolis MN 55410

Voice (612) 924-9193 x 521
Fax   (612) 926-1145

Internet: @spam@dsellnerspam_OUTspam.....embay.com

1995\06\23@135118 by Brian Read

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face
Phillips makes PCF8570 & 8571, 128 X 8 & 256 X 8 Static
RAMs. Both I2C devices in 8 pin packages.

Brian

'More Noise'
1995\06\23@192430 by khladky

flavicon
picon face
In article: <spamBeGone9506231915.aa26619EraseMEspampunt2.demon.co.uk> carlottspamBeGonespaminterport.net writes:
:
:  While the topic is on pseudo random noise generators (well sort of). Does
: anybody have a simple explanation of why specific feedback points are used
: in shift register designs.
:  In the TTL cookbook (an excellent book) Don Lancaster shows the feedback
: points for 2 to 31 stage shift registers (for some odd reason he skips 19).
:  I know the whole point is to have the largest possible sequence before
: repeating, but if you did not have this chart how would you calculate them
: for yourself?

Horowitz and Hill in 'The Art of Electronics' state that the maximum length
sequence is 2^m - 1, where m is the number of bits in the shift register
(obvious) and go on to state 'the criterion for maximal length is that the
polynomial 1 + x^n + x^m be irreducible and prime over the Galois field' (not
so obvious). m being the number of bits, n being the feedback bit.
Interestingly these things are symmetrical, i.e. instead of using the nth bit
you can use the m-n bit to the same effect. And you can use more than two
taps, eg. a 24 bit tapped at 17, 22 and 23 will also give a maximum length
sequence of 1,677,215 cycles. They also list some interesting properties of
maximal length shift registers. Worth looking up.

The advantage of using a PIC would be that you could control the 'clock'
frequency and the sequence length in software, thus shaping the output power
spectrum to your needs - something that the MM5437 couldn't do easily.

Karel
--
++++++++RemoveMEkhladky@spam@spamspamBeGonekhdesign.demon.co.uk++Manchester M14 6BF England++++++++

'Non-Volatile RAM for I2C.'
1995\06\23@195001 by stle.cudenver.edu>

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face
> Date: Thu, 22 Jun 1995 12:24:57 -0700
> From: Brad Morrow <.....morrow@spam@spamEraseMEMOUNTAIN.ASD.SGI.COM>
> Subject: Non-Volatile RAM for I2C.
>
> I need non-volatile RAM for a PIC based design.  Because of size restraints I
> would prefer it interfaced on the I2C bus.  Also, the RAM will be used to stor
e
> individual parameters, requiring modifying single locations.
>
> Does anybody know of companies that have such a product?
>
> --------------------------------------------------------------------------
> Brad Morrow                                         Advanced Systems Group
> Product Design                               e-mail:    .....morrowRemoveMEspamasd.sgi.com
> Silicon Graphics, Inc.                   voice-mail:         (415)390-1311
> 2011 N. Shoreline Blvd.                         fax:         (415)961-9075
> Mountain View, CA 94039-7311
> --------------------------------------------------------------------------

RAMTRON makes I2C serial FRAM parts (and SPI parts, too) in 512- and 2K-byte
sizes; the I2C parts run at 100 or 400KHz with NO WRITE WAIT.  Well, maybe
you aren't in a hurry, but it saves a few lines of code not to have to poll
for the ``done'' status from those SLOW EEPROM parts, and it's also nice to
be able to swallow 115200bps serial data into nonvolatile buffer memory.
Oh, did I mention endurance of 10^10 (10 billion) read or write cycles, and
100uA (microamps) write current?  (FRAM is ``ferroelectric RAM'' -- please
don't let the ``ferro'' confuse you -- it's not a magnetic phenomenon;
there's nothing ferrous involved; it's a polar dielectric effect with
hysteresis which is analogous to ferromagnetism).  Ramtron is in Colorado
Springs, Colorado: (719)481-7000; US:(800)545-FRAM; Fax:(719)488-9095.

Peter F. Klammer, Racom Systems Inc.                   .....PKlammerSTOPspamspam@spam@ACM.Org
6080 Greenwood Plaza Boulevard                            (303)773-7411
Englewood, CO  80111                                  FAX:(303)771-4708

1995\06\23@213830 by Andrew Warren

face
flavicon
face
Doug Sellner (dsellnerEraseMEspam@spam@EMBAY.COM) wrote:

>MicroChip specs only guarntee 100K  write cycles (under normal
>temperature),  wouldn't want to use these for simple index variables.

Doug:

Your information is SERIOUSLY out of date... EEPROM endurance is now 10
million erase/write cycles.

By the way, Clyde Smith-Stubbs mentioned that the Philips parts max out
at 512 bytes.  Microchip have a few parts which hold 8K bytes.

-Andy

--
Andrew Warren - RemoveMEfastfwdspamspamBeGoneix.netcom.com
Fast Forward Engineering, Vista, California

1995\06\23@214244 by Andrew Warren

face
flavicon
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Brian Read <spamBeGonebreadKILLspamspam@spam@MAXWELL.EE.WASHINGTON.EDU> wrote:

>Phillips makes PCF8570 & 8571, 128 X 8 & 256 X 8 Static
>RAMs. Both I2C devices in 8 pin packages.

.. And someone (Xicor or Dallas, I think) makes a chip that contains
both RAM and EEPROM.  The way it works is, you write to and read from
the RAM until your power supply gets low, then the entire RAM array is
automatically copied to EEPROM.  This gives all the advantages of both
RAM and EEPROM, but, of course, costs a little more than either alone.

-Andy

--
Andrew Warren - fastfwdspam_OUTspam@spam@ix.netcom.com
Fast Forward Engineering, Vista, California

'Indestructible (NOT!)'
1995\06\26@091734 by Bryan Crotaz

picon face
> Xref: news.belwue.de sci.electronics:108704 alt.satellite.tv.europe:21159
alt.satellite.tv.crypt:27
>
> In article <spamBeGone104322Z20061995@spam@spamanon.penet.fi>,  <RemoveMEan291156EraseMEspamKILLspamanon.penet.fi> wrote:
> >
> >      To bust a PIC 16C84     connect 13.5v to your VPP supply, make VCC
> >.5 volts less or use a diode .5-.6 is close enough then write 1f to the
> >configuration byte between 3 and 10 times return VCC to normal and read
> >unprotected chip.
> >      If anyone gets this mail can they post it to alt.satellite.tv.europe
> >and alt.satellite.tv.crypt as someone is trying to stop it getting out.
> ---------------------------------------------
> This guy complains it's not getting to Europe. Here goes!
> -Steve Walz  spamBeGonerstevewspam_OUTspamRemoveMEarmory.com

That buggers the nice urban myth of 2000 Amp short currents.....


--
---------------------------------
BRYAN CROTAZ - .....b.crotazspamRemoveMEic.ac.uk
---------------------------------
Engineering & Maintenance
Student Television Of Imperial College
Beit Quad, Prince Consort Road
London  SW7 2BB
Tel. 0171-594-8104
Fax. 0171-594-8065 Attn. STOIC { NOTE NEW FAX NUMBER }

'pic 16c84 not secure?'
1995\06\26@130449 by IP 90)

flavicon
picon face
> I have developed an encryption device which stores the key in
> the C84's internal EE. By design, it is readonly and even then
> not in plain text. However, if it is possible to read the
> program and the EE of the C84, then there is no swecurity left.

> I told the customer that it is possible to reverse engineer almost
> any chip but at rather high cost. He accepted that.

> But now the cost seems to be minimal.

Experience in the pay-TV piracy community indicates that reading out the
PIC16C84 as well as most other common on-chip EEPROM controllers is
surprisingly easy. Most tricks involve strange voltages during programming
or voltage spikes during programming. Other tricks involve modified
programming algorithms which use bugs in the chip that allow write
access to the protection fuse without consequnces for the remaining
software. Most microcontrollers have also packages which are easy to
open by mechanical and/or chemical means (I have done this myself
several times with chip cards) and then selective UV radiation
with a small mask can be used to clear the protection fuse.
These all are tricks a skilled student can perform with a 100 USD budget
at home in his kitchen. Please do not ask for details ... ;-)

You can read-out even well-protected security processors for
cryptographic smart card applications with e-beam testers (although
the manufacturers will never admit how easy it actually is). The
equipment for these attacks costs around 1 million USD but is
available in each better microelectronics lab at semiconductor
companies and research institutions. The normal e-beam testers require
however substantial modifications at the trigger mechanisms in order
to eavesdrop the internal bus lines. This will keep an experienced
engineer a few weeks busy until the chip has been read-out. Monitoring
the current consumption of the chip also allows access to a lot of
information.

Even if you implement your cryptographic algorithms in your own chip as
hardware, the circuitry of the chip can be reconstructed by etching
away thin layers and making SEM images. An automated facitity for this
task has been constructed at Cambridge University and costs
around 2 million USD.

For encryption devices, use at least a dedicated security microcontroller
(e.g. the Motorola 68HC05SC21 or the SGS Thompson ST16F33) which has
been designed for security applications. Better use a secure package
with an alarm mechanism and use battery buffered RAM in order to
store the secret keys. The Dallas DS5002FPM e.g. has been designed for
such applications.

And: it is surprising, how often cryptographic modules (even simple ones)
contain software bugs (e.g. missing boundary checks, hidden channels) which
allow to get access to the contents of the internal EEPROM. Formal software
verification is very important in these applications, because in contrast to
normal bugs, many security problems can not be identified by testing.

Constructing a secure cryptographic module were it is extremely difficult
to get access to the internal secret key is a pretty challanging task.

Markus

--
Markus Kuhn, Computer Science student -- University of Erlangen,
Internet Mail: <mskuhnspam@spam@cip.informatik.uni-erlangen.de> - Germany
WWW Home: <http://wwwcip.informatik.uni-erlangen.de/user/mskuhn>

1995\06\27@021937 by

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face
Danke fuer die Antwort.

> > I told the customer that it is possible to reverse engineer almost
> > any chip but at rather high cost. He accepted that.

Damit hatte ich auch an die von Dir weiter unten beschriebenen Verfahren
gedacht. Bei Kosten von >$1.000.000 fuer eine Erstaustattung oder
$10.000 pro Auftrag macht mir das nichts aus. Denn jedes Teil hat ja
einen anderen Schluessel und muss individuell geknackt werden.

> > But now the cost seems to be minimal.
>
> Experience in the pay-TV piracy community indicates that reading out the
> PIC16C84 as well as most other common on-chip EEPROM controllers is

Ja. Auf diesen Thread hatte ich mich auch bezogen. Man muss halt Elektronik
im Wert von 10.- spendieren (ohne SMD-Sockel), um den dortigen Vorschlag
auszufuehren ...


> surprisingly easy. Most tricks involve strange voltages during programming
> or voltage spikes during programming. Other tricks involve modified

Habe ich auch schon mal gemacht (80C49, ROM). Liess sich lesen, obwohl undokumen
tiert.
Das ist aber schon 10 Jahre her. Ich dachte, inzwischen haetten die Hersteller
dazugelernt :((

> Most microcontrollers have also packages which are easy to
> open by mechanical and/or chemical means (I have done this myself
> several times with chip cards) and then selective UV radiation

Gut! Ich habe das mit SO-ICs noch nicht geschafft, allerdings haette
ich vermutlich besser erst mal einen Chemiker gefragt.

> Monitoring
> the current consumption of the chip also allows access to a lot of
> information.

Daran (und auch an das zeitliche Verhalten) habe ich gedacht. Das kann
man aber "ausgleichen".

> For encryption devices, use at least a dedicated security microcontroller
> (e.g. the Motorola 68HC05SC21 or the SGS Thompson ST16F33) which has
> been designed for security applications. Better use a secure package
> with an alarm mechanism and use battery buffered RAM in order to
> store the secret keys. The Dallas DS5002FPM e.g. has been designed for
> such applications.

Danke fuer die Hinweise. Problematisch koennten die anderen Randbedingungen
werden (3V, <5mA). Kann ich aber ohne Kenntnis der Datenblaetter noch nicht
sagen. SGS hat oft "traumhafte" Lieferzeiten. Sie wollen 5000 ST93CS46?
Kein Problem, so in ca. einem Jahr ... (52 Wo).

> And: it is surprising, how often cryptographic modules (even simple ones)
> contain software bugs (e.g. missing boundary checks, hidden channels) which
> allow to get access to the contents of the internal EEPROM. Formal software
> verification is very important in these applications, because in contrast to
> normal bugs, many security problems can not be identified by testing.

Stimmt. Deswegen habe ich z.B. auch keinen "Testmode", mit dem man den Key
lesen koennte (obwohl das fuer die Ueberpruefung der Programmierung nett waere).
Subkeys werden nie in RAM-Bereichen abgelegt, die evtl. bei einer Datenuebertrag
ung
als Buffer genutzt werden, auch wenn die Abarbeitung immer sequentiell ist.
Es gibt immer externe "Stoerungen", die einen armen PIC dazu veranlassen
koennen, den Code "sonstwo" fortzusetzen ...

> Constructing a secure cryptographic module were it is extremely difficult
> to get access to the internal secret key is a pretty challanging task.

Leider (oder gottseidank). Habe von einem Vorlaeufer immerhin einige Tausend
verkauft. Wurde bisher nicht geknackt.

Aber jetzt muss ich doch mal mit Microchip hier in Muenchen reden.

Michael

--
Dipl.-Ing. Michael Hermann   EraseMEmchRemoveMEspamSTOPspamregent.e-technik.tu-muenchen.de
Lehrstuhl fuer Rechnergestuetztes Entwerfen,     Postfach 202420
Technische Universitaet Muenchen                    089/21053651

1995\06\27@034016 by divanov

flavicon
face
> > For encryption devices, use at least a dedicated security microcontroller
> > (e.g. the Motorola 68HC05SC21 or the SGS Thompson ST16F33) which has
> > been designed for security applications. Better use a secure package
> > with an alarm mechanism and use battery buffered RAM in order to
> > store the secret keys. The Dallas DS5002FPM e.g. has been designed for
> > such applications.

Just a short 'afterthougth'. Dallas makes a Touch Multikey -- DS1991.
It's a small can, powered by a lithium cell, and stores 3 large keys,
each accessible through a 64bit password using a 1wire bus. They
guarantee 10 years data retention, or until someone attempts to open
the can : )

> Aber jetzt muss ich doch mal mit Microchip hier in Muenchen reden.

Wenn Du mit Microchip in Muenchen redest, dann ist es ganz recht
Deutsch zu benutzen. Leider, koennen nicht alle auf dem Piclist das
gleiche tun : ) .

Regards,

Richard Ivanov (Test Equipment Design Engineer)

'Verified: 16C84 not secure'
1995\06\27@082812 by

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face
Hi all,

first please excuse my previous note in German. This was due
to an accident, as I wanted to reply to someone specific.

Now to the bad news:

I have just spoken to a local representative of Microchip
and got the information that the current revision of the
16xx84 is NOT SECURE. Microchip knows about the problem
and plans to completely rework the design, however, this
will not be available in the near future.

According to this source the 16xx71/16xx61 (which I have used
to great extent in the past) do not suffer from this problem.
The source won't guarantee for absolute security, however,
"it is not that easy as with the 16xx84".


While I do appreciate that MC acknowledges the problem I'm
hoping that MC will tell their customers next time w/o
question.

I imagine that quite a few people base their design on the
existance of code protection and it would be nice to inform
them before major investments have been made on false assumptions.

I my case, I'm now loosing "only" the already working prototypes.

In the worst case I would not only have lost several thousands of
devices but also my reputation and probably I would be liable
for fraud.

Mike


--
Dipl.-Ing. Michael Hermann   RemoveMEmchKILLspamspamTakeThisOuTregent.e-technik.tu-muenchen.de
Lehrstuhl fuer Rechnergestuetztes Entwerfen,     Postfach 202420
Technische Universitaet Muenchen                    089/21053651

'16LC84 not secure (2nd try)'
1995\06\29@073110 by

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face
Hi,

I think my previous attempt to post this info to the list
didn't make it.

This is a short repost.

I have contacted my local representative of Arizona Microchip
and got the information, that the current revision of the
16C84 has a security problem. AM is in the process of a complete
redesign which will eventually lead to the 16C84A. They expect
this to take long.

The other products (I asked specifically for 16C71 and 16C61)
do not suffer from this problem, according to AM.

I'm now looking for a replacement, which must meet some constraints
AND of course be secure.

1. at most 24 pin SO package, better 18-20.
2. at least 1K OTP-ROM, much better Flash or EE
3. at least 32 bytes RAM, if no internal EE: at least 64 bytes
4. at least 2.7V@5mA, better 2.0V@3mA (of course :))
5. internal (secure) EE preferred, at least 32 Bytes
6. reasonably fast (not dog-slow as ST62xx)

I'm (again) gathering Info starting with Atmel and ending at Zilog.
However, I'd be really glad for any additional specific input from
the list. Any comments?

Mike

--
Dipl.-Ing. Michael Hermann   spamBeGonemchspam@spam@regent.e-technik.tu-muenchen.de
Lehrstuhl fuer Rechnergestuetztes Entwerfen,     Postfach 202420
Technische Universitaet Muenchen                    089/21053651

1995\06\29@105014 by Greg Riddick

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face
Mike,
For a replacement of the PIC16C84, I would look at the lower end
ATMEL chips: 1-2k Flash,128 ram,20 pins. Power requirements may
be a little high for your application, and there is code
protection. You would probably have to talk to ATMEl to see how
secure the device is.

Greg


'HC05 Pricing (was: "Re: 16LC84 not secure")'
1995\07\03@110517 by Pic User
flavicon
face
I just paid 1.60 each for 10 HC705J1's (OTP)from FAI.  I debated between the J1
and PIC
61's.  After  I thought out the pro's and con's of each, I stayed with the PIC e
ven
though it's three times as much.  If I get into the thousands of units I will ha
ve to
re-evaluate.

Steve

----------{Original Message removed}

'ANNOUNCE: programs for download'
1995\07\08@215434 by David B. Thomas

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face
I put some pic programs that I've promised I'd make available on a web
page.  You can get to them with http://www.rt66.com/dthomas/pic/pic.html

There's a guitar tuner, a midi sender and a dtmf tone generator.

David
--
Their address sums up their attitude: One Microsoft Way
       http://www.rt66.com/dthomas/

'The 10 pm problem, now 11:30 odd....'
1995\07\14@072313 by stephnss

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face
> As it turns out, it looks like the crystal was dodgy.  I applied an
>external oscillator and the PIC happily started running.  So I'll buy a
>new crystal in the morning and 'touch wood it might even work... :-) :-)

If your new crystal doesn't work, and your using a prototyping board, it may
be that you have a problem with groundplanes. Once I had a problem with a
16C54 that only worked when the protoboard it was on was lifted an inch off
my metal desktop.

'115 inst int service no W or S ?????'
1995\07\25@224430 by Andrew Warren

face
flavicon
face
Nick Howard (RemoveMECHP3HOWARNJspam_OUTspamNTU.AC.UK) wrote:

>I'm interested to know what [your 115-byte interrupt service routine
>which affects neither W nor Status registers] does, I suppose one
>could have a delay with 115 NOPs or maybe it's a lookup table but then
>if there' a zero value .....

Nick:

The code is for an automotive ignition controller; I think I can give
you an overview without letting any of my client's secrets out, so....

First, it determines whether the interrupt came from TMR0 overflow or
from PortB-change.

If PortB-Change, it:

   Checks the state of the distributor-points signal.  If low, it
   jumps to DIS_RB, below.

   Otherwise, it checks a couple of things to make sure that this
   interrupt wasn't triggered by a very fast noise spike.  If it was,
   the PIC jumps to SETDB, below.

   Otherwise, it checks that the points signal was low for at least
   512 microseconds before this hi-going edge (for debounce purposes).
   If not, it jumps to SETDB.

   Otherwise, it checks the engine speed and, if it's not above the
   user-set rev-limit, it fires a spark.

   Either way, we set a couple of flags and jump to RB7INT_EXIT.

   DIS_RB:

   This section is executed whenever we see a low-going edge on the
   points signal.

   It checks a couple of things to make sure that this interrupt
   wasn't triggered by a very fast noise spike.  If it was, the PIC
   jumps to RB7INT_EXIT, below.

   Otherwise, it disables PortB-Change interrupts (they'll be
   re-enabled in the main code before the next hi-going points-signal
   edge) and sets a couple of flags.

   DBSET:

   This section is executed whenever we see a falling edge on the
   distributor-points signal or a rising edge after less than 512
   microseconds of low time on the points signal.

   It simply sets a flag and starts the 512-microsecond debounce
   timer.

   RB7INT_EXIT:

   This part just clears the PortB-Change Interrupt Flag and does a
   RETFIE.

If the interrupt was generated by a Timer-0 overflow:

   The code clears the Timer-0 Overflow Interrupt Flag and sets
   another flag.

   Next, it updates the states of two LEDs.  This is a little
   involved; there are 5 different dual-LED blink patterns, each
   repeating every two seconds.  The particular pattern it displays is
   based on the readings it got from three A/D inputs in the main
   code.

   Next, it counts down the 512-microsecond debounce timer (making
   sure that it never decrements past 0).  If it was just decremented
   to 0, the code sets a flag so that the PortB-Change interrupt
   handler knows that the signal has been debounced.

   Finally, it increments a three-byte real-time clock and does a
   RETFIE.

As I stated in my previous message, this whole process takes 115
instructions, none of which affect the W register or any
STATUS-register flags.

-Andy

--
Andrew Warren - fastfwdspamspamix.netcom.com
Fast Forward Engineering, Vista, California


'Nitinol wires'
1995\08\16@024014 by Mark G. Forbes
flavicon
face
I think that 50VDC will be reasonably safe so long as it's
indoors, in a dry area, and the voltage is not referenced to
earth ground. Put whatever protection you can around the area
to reduce the chance of people grabbing things.

That said, I think there's a significant chance of injury
due to *thermal* burns. That Nitinol wire gets pretty hot,
as I recall, and there should be enough power dissipated to
give somebody a nasty burn. You're more likely to have trouble
due to this than from electric shock. Remember McDonald's
and the infamous 'hot coffee' lawsuit!

Why would you want art lovers to touch this thing anyway? Those
wires aren't very rugged, and the first ham-handed six-year-old
that gets close will destroy it in seconds. And probably think
it's funny, too.......

spam_OUTforbesmspam_OUTspamspam_OUTpeak.org   KC7LZD
Mark G. Forbes
"Never ascribe to malice that which can be blamed on the engineer."

'Enough, dammit!'
1995\08\22@005541 by Andrew Warren

face
flavicon
face
So far, this list has received... What?  Half a dozen unsolicited
"spam" advertisements?

Big deal.  Those of us with smart newsreaders can just use kill files
to automatically delete these things, and the rest of you can just
delete the messages as soon as you realize what they're about.

Kill file or no, the occasional spam is nowhere near as annoying as
this INCESSANT chatter about possible solutions, "revenge", etc.  If
you feel the need to jabber on and on about the subject, do it on
alt.net-abuse or alt.spam.

If you're overcome with the desire to get back at the spammers, send
mail to "postmaster@[spammer's domain-name]", or check out the
Blacklist of Internet Advertisers at:

   math-http://www.uni-paderborn.de/~axel/BL/blacklist.html

My newsreader is now configured to kill all mail with "sorgi", "Jeff
Slaton" or "spam" in the subject line, but if one more message slips
through with -- Christ, I can't BELIEVE anyone is this stupid -- the
ENTIRE TEXT of the original spam quoted, I'm gonna hurt someone.

-Andy

P.S.  In the interest of practicing what I preach, I've just configured
     my newsreader to kill any reply to this message sent to the list
     at large, so if you have a problem with anything I've said here,
     send it to me in private e-mail.

--
Andrew Warren - fastfwdspam_OUTspamix.netcom.com
Fast Forward Engineering, Vista, California

1995\08\22@045758 by mauricio

flavicon
face
> From:        Andrew Warren <RemoveMEfastfwdKILLspamspam@spam@IX.NETCOM.COM>

. . .
> Kill file or no, the occasional spam is nowhere near as annoying as
> this INCESSANT chatter about possible solutions, "revenge", etc.  If
> you feel the need to jabber on and on about the subject, do it on
> alt.net-abuse or alt.spam.
. . .

I agree, Andrew!


Mauricio CULIBRK

ARNE Computers d.o.o.
Cesta v Gorice 38                                   Phone:   +386 61 1233-171
61111 Ljubljana                                     Fax:     +386 61 1233-488
Slovenia                                            E-Mail:  mauriciospamBeGonespam.....arne.si
E U R O P E

'Ready for non-window pics'
1995\08\22@184517 by Mike Keitz

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face
Martin Kirk <KILLspammlkspam.....asu.edu> wrote:
>Hi,
>
>Will someone please give me a brief list of the requirements for clearing
>the registers when moving one's code to non-windowed pics?  I assume it
>is a simple clear all registers operation.  Please confirm.
>

AFAIK, the non-window PICs have *exactly* the same chip in them as the
window ones.  So there should be no difference in operation between one type
and the other, other than inability to erase the non-window one.

(In an earlier thread, someone noted that newer versions of the window chips
have a non-erasable code protect bit.  So if this bit is set, a windowed
chip would be non-reusable as well.  Has Microchip issued an exact statement
on this?)

If you're counting on light through the window setting the RAM (registers?)
in a certain condition, this is very bad practice, not certain to work in
any case.  It is important to design your code so it doesn't assume anything
about the state of the RAM on power-up.  The special function registers are
reset as described in the table in the data book, but the RAM is not
guaranteed to be reset to any particular state, window chip or not.

There is no single "clear all registers" instruction.  However the FAQ
contains a good example of a loop which will do it.  Depending on the number
of locations that must be cleared for your code, it may be simpler to just
use a few clrf's on the vital locations.

-Mike

1995\08\22@195937 by Paul Christenson [N3EOP]

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face
>Will someone please give me a brief list of the requirements for clearing
>the registers when moving one's code to non-windowed pics?  I assume it
>is a simple clear all registers operation.  Please confirm.

Simpler than that.  Simply be sure to initialize each register before you
use it.  (Don't assume that it'll be zero before it's used.)

1995\08\23@005055 by Andrew Warren

face
flavicon
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Martin Kirk (spam_OUTmlkspamKILLspamASU.EDU) wrote:

>Will someone please give me a brief list of the requirements for clearing
>the registers when moving one's code to non-windowed pics?  I assume it
>is a simple clear all registers operation.  Please confirm.

Martin:

For the 16C54/55/56:

   PORTA   EQU     004H

           MOVLW   PORTA       ;PREPARE TO ZERO ALL REGISTERS EXCEPT THE FSR,
           MOVWF   FSR         ;RTCC, PC, AND PROCESSOR STATUS REGISTERS.

   CLRRAM  CLRF    USEFSR           ;ZERO A REGISTER.

           INCFSZ  FSR         ;HAVE WE DONE THEM ALL?
           GOTO    CLRRAM           ;IF NOT, LOOP BACK AND ZERO ANOTHER.

For the 16C57/58:

   PORTA   EQU     004H

           MOVLW   PORTA       ;PREPARE TO ZERO ALL REGISTERS EXCEPT THE
           MOVWF   FSR         ;PROCESSOR STATUS, PC, RTCC, AND FSR
                               ;REGISTERS.

   CLRRAM  MOVLW   00011111B   ;ARE WE POINTING AT "USEFSR"?
           ANDWF   FSR,W       ;

           SKPNZ               ;IF NOT, SKIP AHEAD.

           BSF     FSR,BIT4    ;OTHERWISE, SKIP OVER THE PROCESSOR STATUS,
                               ;PC, RTCC, FSR, PORTA, PORTB, PORTC, AND
                               ;THE GLOBALLY-ACCESSIBLE FILE REGISTERS.

           CLRF    USEFSR      ;ZERO THE REGISTER AT WHICH WE'RE POINTING.

           INCFSZ  FSR         ;HAVE WE DONE THEM ALL?
           GOTO    CLRRAM      ;IF NOT, LOOP BACK AND ZERO ANOTHER.

   ; ALL FILE REGISTERS ARE ZEROED AND WE'RE IN DATA SEGMENT 0.

For the 16C71:

   GPREGS  EQU     00CH
   LASTGP  EQU     02FH

           MOVLW   GPREGS+1        ;CLEAR ALL GENERAL-PURPOSE REGISTERS.
           MOVWF   FSR             ;THIS ROUTINE WAS WRITTEN BY DON LEKEI.
           MOVLW   LASTGP-GPREGS   ;
           MOVWF   GPREGS          ;
                                   ;
   CLRRAM  CLRF    USEFSR          ;
                                   ;
           INCF    FSR             ;
           DECFSZ  GPREGS          ;
           GOTO    CLRRAM          ;

For the 16C74:

   FRSTGP0 EQU     020H
   LASTGP0 EQU     07FH

           MOVLW   FRSTGP0     ;PREPARE TO ZERO ALL GENERAL-PURPOSE
           MOVWF   FSR         ;REGISTERS.

   CLRRAM  MOVLW   LASTGP0+1   ;ARE WE POINTING PAST THE FINAL PAGE-0
           XORWF   FSR,W       ;REGISTER?

           SKPNZ               ;IF NOT, SKIP AHEAD.

           BSF     FSR,BIT5    ;OTHERWISE, ADJUST FSR TO SKIP OVER THE PAGE-1
                               ;SPECIAL-PURPOSE REGISTERS.

           CLRF    USEFSR      ;ZERO THE REGISTER AT WHICH WE'RE POINTING.

           INCFSZ  FSR         ;HAVE WE DONE THEM ALL?
           GOTO    CLRRAM      ;IF NOT, LOOP BACK AND ZERO ANOTHER.

In addition to the equates shown in the above code fragments, you should be
aware that "USEFSR" is my name for the indirect register (register number 0);
some Microchip documentation now refers to this register as "INDF".

"FSR", of course, should be equated to the appropriate register (this is left
as an exercise for the reader).

Enjoy...

-Andy

--
Andrew Warren - RemoveMEfastfwdRemoveMEspamEraseMEix.netcom.com
Fast Forward Engineering, Vista, California

1995\08\23@144349 by PETE KLAMMER

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face
I received on Tue, 22 Aug 1995 18:44:59 from Mike Keitz <KILLspammkeitzspamspamBeGoneBEV.NET>:

> Subject: Re: Ready for non-window pics
>
> Martin Kirk <mlkspamspamasu.edu> wrote:
> >Hi,
> >
> >Will someone please give me a brief list of the requirements for clearing
> >the registers when moving one's code to non-windowed pics?  I assume it
> >is a simple clear all registers operation.  Please confirm.
> >
>
> AFAIK, the non-window PICs have *exactly* the same chip in them as the
> window ones.  So there should be no difference in operation between one type
> and the other, other than inability to erase the non-window one.
>
> (In an earlier thread, someone noted that newer versions of the window chips
> have a non-erasable code protect bit.  So if this bit is set, a windowed
> chip would be non-reusable as well.  Has Microchip issued an exact statement
> on this?)

I have two PIC17C44-JW (windowed) engineering samples, one now a doorstop,
the other now a paperweight.  Microchip did confirm that the code-protect on
these windowed parts is not erasable.  One representative told me that there
is some kind of metal or metalization over those fuses.  Since the dice are
exactly the same in windowed and OTP parts, this is obviously intended to
make it more difficult for a would-be hacker to split open an OTP package
and create his/her own ``window'' to selectively erase the code-protect fuse
of a code-protected part.  When I posted my speculations on the MCHIPBBS
about the implementation (some fuse bits are eraseable, some are not) it was
removed and I was sent a private BBS mail message explaining that management
was understandably touchy about the topic.

The only difference between windowed and non-windowed parts is that an
erased windowed part tends to come up initialized the same way every time,
with zeros in lots of places which should not be relied upon.

Peter F. Klammer, Racom Systems Inc.                   RemoveMEPKlammerspamBeGonespamRemoveMEACM.Org
6080 Greenwood Plaza Boulevard                            (303)773-7411
Englewood, CO  80111                                  FAX:(303)771-4708

'A little advice for a novice?'
1995\08\30@155934 by Carl Connett

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face
Been on the list a few weeks now, trying to figure out where to
begin.  My first question was about PICs in general and I appreciated
the responses I got.  But I'm fast learning that I have a lot of
ground work to accomplish before I get into PIC's.  I think I want to
start learning about control using the XT sitting on my desk at home.
Maybe write some BASIC to control a stepping motor, then advance to
learning about Assembly-type languages.  From there, move into the
PIC world.  So my request for advice is about rudimentary stuff:  do
you know where I can direct my looking to find out about writing code
that uses the parallel or serial port on my XT?  If you care to
reply, feel free to write me direct, rather than clutter up this good
list with something nearly off-subject.  Thanks.
Carl Connett
Manufacturing Services
DaySpring Cards
PO Box 1010
Siloam Springs, AR  72761
Phn: 501.549.9251
Fax: 501.524.8813

mhs:carlc@outreach (compuserve)
KILLspamcarlcspamBeGonespamoutreach.mhs.compuserve.com (internet)


'Another PIC system with Basic Interpreter!'
1995\09\01@114400 by Don McKenzie
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face
This months issue of Silicon Chip (Australia) carries an advertisment for
yet another Basic Interpreter system.

I thought someone out there may know more about it or at least be
interested in its existance. The Ad. reads as follows:

FBASIC TICkit has 21 I/O

>From VersaTech PIC16C57 @ 20MHz, on a 65mm square board, has an on-board
interpreter, 16 GP I/O, plus 5 I/O for IRQ, IRQ ack RTC/Counter IIC buss,
handles SRAM and LCD too! Stores program in 8K EEPROM.

Don...

Don McKenzie                ~~   _--_|\    ~~   Email: @spam@donmckSTOPspamspam@spam@tbsa.com.au
29 Ellesmere Cres.,         ~~  /      `\  ~~   Phone:   + 61 3 9338 6286
Tullamarine 3043 Australia  ~~ (         ) ~~  Mobile:   + 61 019 939 799
(10 Miles from Melbourne)   ~~  \/~^~\_@/  ~~   Same address for 21 years
See my promo.zip disk at:   ~~         v   ~~
ftp://rasi.lr.ttu.ee/pub/sis/prod/microchip/3rd-Party/Don.McKenzie/

'The MIPI concept (now MIPP concept)'
1995\09\05@094232 by Siegfried Grob

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Hi David, hi John, hi everyone interested in a bootstrappable MIPP
(MIPP = Machine Independent Pic Programmer)

David Tait said:
~~~~~~~~~~~~~~~~

> OK.  Putting the ideas from Walter Anderson, Carl Ott and Roger Books
> together we have a 16CXX-only programmer, that initially uses a circuit
> to emulate the controller PIC, but a circuit which is simple enough to
> be "breadboardable" and disposible.  If we follow this line of thought
> for a bit we see that the RS232 interface and the few transistors that
> are needed to control MCLR can be built as part of a skeleton final
> programmer (let's not bother trying to switch VDD, though we can provide
> +5V for programming PICs that are not already in circuit).  We get
> something like this:

            +----------+      +----------+      +----------+
     TXD    |          |      |          |      |          |
      >-----|          |------|  EMPTY   |------|  THREE   |------> MCLR
            |  RS232   |      |  18-PIN  |      |TRANSISTOR|------> VDD
     RXD    |INTERFACE |      |  SOCKET  |------|   ISP    |------> RB6
      <-----|          |------|          |------| CIRCUIT  |------> RB7
            |          |      |          |      |          |
            +----------+      +----------+      +----------+




> The "PIC emulator" (i.e. something like my MIPI circuit) is connected
> to an 18-pin header and (perhaps using a special version of the
> final host processor software) used to burn a 16C84.  The PIC
> emulator is thrown in the bin and replaced by the 16C84 and we
> have the final programmer (not universal anymore, but perhaps Walter's
> argument has convinced you that the 16C5X series are not likely
> to be used in new designs).



John Payson said:
~~~~~~~~~~~~~~~~~

For doing "blind" programming of an '84 ["blind" meaning the host can't
tell anything about what the PIC is doing, or even its existence] I think
the simplest possible circuit is two resistors and a cap [plus the power
supplies].

R1 should be about 10K or so and should connect the PIC programming clock to
TxD.  R2 should be a 10K POT between the PIC programming data and TxD.  The
cap should be about 0.1uF or so and should connect the pgm data line to ground.
To send a "1" bit, send 00h; to send a "0" bit, send FFh.


My opinion:
~~~~~~~~~~~

Concatenating the thoughts of David and John, I would create a 16Cxx-programmer
based on the architecture that was drawn above by David.
In the 18pin socket is a 16C84 as the controller, unprogrammed at the very
start.
Insert John's 'blind programming' hardware between the 16C84 and the RS232-
interface so that the 16C84 can be in-programmer programmed in its own socket.
Afterwards the 16C84 acts as an intelligent programmer's controller. Later the
blind in-programmer method can be used to update the C84's firmware.
The advantage is obvious: there are no redundant parts or breadboards after
bootstrapping, with minimum amount of additional hardware. You don't need a
'PIC-emulator' as David described, because the PIC is programmed in its own
'controller socket', not in the later to use 'programming socket'.


The core of this universal 16Cxx-programmer looks like this:

(R1 is unnecessary with MAX232)

                                        |    Programmer's PIC 16C84
                             R1         |
TxD ----------------*----[10k]---------- |Clock/RB6
(maybe via MAX232)  |                    |
                   `----[10k]----*------|Data/RB7
                        R2       |      |
                                --- C   |
                                ---.1uF |
                                 |      |
                                ///     |
                                        |
RxD (via MAX232) ------------------------|for later communication with host
(or via OP-AMP for level shift)          |
                                        |
                     Vcc---O            |
                             \          |
          Switch: On/off/on    \O--*----|MCLR, switched to Vcc/Vpp manually,
                                   |    |  Vcc for normal operation later
                     Vpp---O     [10k]  |
                                   |    |
                                  ///   |
                                        |
Three transistor ISP ciruit =============|all necessary pins for serial
                                        |       programming other PICs
                                        |


Don't you think this is worth to be built?

Siggi


Siegfried Grob,                                   |
student of electrical engineering,                |
university of ulm, germany                        |
e-mail:  siegfried.grobspamBeGonespamspamBeGonestudent.uni-ulm.de        |
tel&fax: +49 731 25148                            |
--------------------------------------------------'

'Acknowledge (Was: Fuzzy controllers)'
1995\09\06@190308 by Ronny H. Kavli

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face
>>(Do not ask me about details regarding this code, as I _not_ am the
>> author of this code - Kavli)
>
>    No kidding, Ronny... How about asking the authors of FIDE for
>    permission before you go posting their copyrighted code to the
>    world?  Or at least acknowledging the copyright?

Since Andrew Warren has forced me :-) to investigate in this, the
author of the code I supplied is Raymod Carr. I don't know if he was
employed by Aptronix at the time the code was written or if the code
was bought by Aptronix at a later date or whatever.

In any case Raymond should be acknowledged for writing that code.
Newer versions of the code can be found by anonymous ftp at:

ftp.gre.ac.uk:/pub/robotics/motorola/mcu11/

Regards,
-------------------------------------------------------------------------------
Ronny H. Kavli                      This message was composed by 10,000 monkeys
spamBeGonekavlispamludd.luth.se                  keying on 10,000 computers.  It was then
Lulea Academic Computer Soc.(Ludd)  merged using COBOL.  This was of course
Lulea University, Sweden            all done under a government contract.

'YOU KNOW YOU WANT TO BE SUCCESSFULL'
1995\09\07@104012 by MIKE HOLLOWAY

picon face
WOULD YOU LIKE TO MAKE ALOT OF MONEY?  I have made a fortune in the AMWAY
Business opportunity.  For more information on how YOU can be a distributor
for the most exciting business opportunity of the 90's, ...
PLEASE SEND AN E-MAIL REPLY TO:  spam_OUTmhollowaSTOPspamspamcris.com (MIKE HOLLOWAY).

I will be happy to discuss YOUR FUTURE in detail in this lucrative business!

Best Wishes for your Future SUCCESS!

MIKE

1995\09\07@110850 by ERROL TERBLANCHE

flavicon
face
What was that AD about??

Can't mail from non subscribers be cept out?? :)

Wondering
Errol

1995\09\07@125014 by Daniel Mahoney

picon face
>
> WOULD YOU LIKE TO MAKE ALOT OF MONEY?  I have made a fortune in the AMWAY
> Business opportunity.  For more information on how YOU can be a distributor
> for the most exciting business opportunity of the 90's, ...
> PLEASE SEND AN E-MAIL REPLY TO:  RemoveMEmhollowaspamspamcris.com (MIKE HOLLOWAY).
>
> I will be happy to discuss YOUR FUTURE in detail in this lucrative business!
>
> Best Wishes for your Future SUCCESS!
>
> MIKE
>

This shit does not belong on mailing lists, especially not a list like
the PIC microprocessor list.  Keep this shit to yourself, don't bother
us with it.

--
-----------------------------------------------------------------------
Daniel Mahoney                                          Product Manager
TakeThisOuTdmahoneyspamspamRemoveMEnetcom.com                       Comarco Wireless Technologies
Riverside, CA                                                Irvine, CA
(909) 360-3647 (home)                                    (714) 450-4076

1995\09\07@155250 by m.d.simpson.bra0505

flavicon
face
I've sent him 10 1MB mailings with text along the lines of, we
don't appreciate it, don't do it.  It looks like the only way to
teach these people is to use fire on fire.  Perhaps if it costs
him money to download junk, perhaps he'll be more considerative
of others.
Mark

1995\09\08@082805 by ose G. Pineda A. ELECTRONICO

flavicon
face
:
:WOULD YOU LIKE TO MAKE ALOT OF MONEY?  I have made a fortune in the AMWAY
:Business opportunity.  For more information on how YOU can be a distributor
:for the most exciting business opportunity of the 90's, ...
:PLEASE SEND AN E-MAIL REPLY TO:  KILLspammhollowaspamspamspam_OUTcris.com (MIKE HOLLOWAY).
:
:I will be happy to discuss YOUR FUTURE in detail in this lucrative business!
:
:Best Wishes for your Future SUCCESS

       Mike get me more information



--
|      ~~     ~~   /^\           | Jose Pineda
|  ~~     /^\    /     \   ~~    | Fax    : +58 2 2426039
|       /_    \/   _     \    ~~ | E-mail : jpinedaRemoveMEspamdino.conicit.ve
|     /  # _   # _ # _ _   \     | Caracas, D.F.
|   /    # # _ # # # # # _   \   | Venezuela
|_/______#_#_#_#_#_#_#_#_#_____\_|

'A little advice for a novice?'
1995\09\13@223511 by William D. McMillan

picon face
Well, the best 'cookbook-style' approach to bit-banging the parallel port iis
Gordon McComb's "Robot Builder's Bonanza", ISBN 0-8306-2800-2.  Only $16.95
US.  For my final sophomore project a few  years back, I used it to help me
automate a small robot arm in QBASIC on an old Tandy 286 laptop.  Now if I
could only find an equally siimple and straightforward tutorial on using the
COM ports, I'd be all set.....sigh.

1995\09\14@105245 by Mike Schreck

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face
All,

>William D. McMillan wrote:
>Now if I could only find an equally siimple and straightforward
>tutorial on using the COM ports, I'd be all set.....sigh.
Check out the back issues of MicroComputer Journal, about summer 94
there was a series of articles on IBM PC Serial/parallel ports.

Michael J. Schreck

1995\09\14@120407 by Stuart Allman

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face
On Thu, 14 Sep 1995, Mike Schreck wrote:

> All,
>
> >William D. McMillan wrote:
> >Now if I could only find an equally siimple and straightforward
> >tutorial on using the COM ports, I'd be all set.....sigh.

I prefer to use the windows Serial Port API.  The sample application
"TTY" that comes with Visual C++ should do the trick.  It will handle all
of the low level stuff while you concentrate on your hardware.

Stuart Allman
EraseMEstudioSTOPspamspamRemoveMEhalcyon.com

1995\09\14@131426 by Jizhong Wang

flavicon
face
>>William D. McMillan wrote:
>>Now if I could only find an equally siimple and straightforward
>>tutorial on using the COM ports, I'd be all set.....sigh.

Check   http://www.paranoia.com/~filipg/HTML/LINK/PORTS/F_Parallel.html

You will find what you needed.

-------------------------------------------------------------------------
Jizhong Wang                      Q: How does a constipated mathematician
                                     solve his problem?
spam_OUTJizwangRemoveMEspamEraseMEcc.UManitoba.CA           A: He works it out with a pencil.  :<
http://home.cc.umanitoba.ca/~jizwang
-------------------------------------------------------------------------

'YOU KNOW YOU WANT TO BE SUCCESSFULL'
1995\09\17@121313 by John W. Gutmann

flavicon
face
Mike,
   This letter is unwanted in the PIClist.   NO MORE PLEASE
   John W. Gutmann


--
__   _  _  _  _   John W. Gutmann  -  SYSOP -  Robots R4U BBS - 404-978-7300
|__)  |__|  |  |   TakeThisOuTjohn.gutmannRemoveMEspam@spam@robot4u.atl.ga.us              INTERNET EMAIL
|  \     |  |__|   ROBOT HOBBY; The Complete Manual for Individuals and Clubs
__    __    __    R.E.A.L. - Robot Experimenter Amateur League - Atlanta, GA
|__)  |__)  (__    ROBOTS R4U BBS -  P.O. Box 2050  - Stn. Mtn., GA  -  30086
|__)  |__)   __)   Voice 404-972-7082  Ans Machine  -  FAX 404-979-3660,,,,11

'SIGNOFF PIC'
1995\09\20@090112 by Ian Knoetzen

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face
SIGNOFF PIC

> List PIC is unknown to EraseMELISTSERVRemoveMEspamMITVMA.MIT.EDU.

Please remove my name from the PIC list.

PIC user :  spamKNOETZEN.....spamspamFIRGA.SUN.AC.ZA

Thanks

Ian

'...no subject...'
1995\09\28@163626 by RAM6%RnD%RnD

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face
Has anybody heard of, or experienced PIC16C74's not meeting temperature
specs? I have a couple of em' that seem to get lost at around 10 C. These are
not industrial parts, but should get down to at least 0 C.

Rodger Mayeda
Pacific Gas and Electric Co. R&D

'Dead at 10C? [was ...no subject...]'
1995\09\28@174415 by Mike Keitz

flavicon
face
>Has anybody heard of, or experienced PIC16C74's not meeting temperature
>specs? I have a couple of em' that seem to get lost at around 10 C. These are
>not industrial parts, but should get down to at least 0 C.
>
If you are using the internal oscillator with a crystal, it is possible that
the characteristics of the oscillator amplifier change enough that it quits
oscillating.  Try changing the value of the load capacitors (you do have
load capacitors on there, right?  It won't work reliably at any temperature
without them).  Of course, the oscillator select fuses need to be set
properly for the frequency being used.  Perhaps selecting the HS oscillator
even if the frequency is near 4 MHz would give the oscillator a little more
gain and help it work when cold.

If this is a production unit, considerable testing of the oscillator should
be done to be sure that it works reliably with your particular choice of
crystal, capacitors, and PC board layout.  Try turning the power on, both
higher and lower than normal voltage, at various temperatures while
observing the operation of the oscillator.  The startup time of the
oscillator is a good indication of how well it wants to oscillate.  To avoid
loading the oscillator down, use a simple test program that toggles a pin as
soon as the PIC starts and monitor that pin.  Also checking the peak-to-peak
level at the X1 pin shows how strongly it is running (ideally, 5V p-p or
more).  This test is almost certain to affect the result though due to
loading from the scope, so results should be taken with a grain of salt.

Another potential source of trouble is the WDT.  As the temperature falls,
the WDT is likely to run faster. (I don't see any proof of that in the data
sheet, but being a RC oscillator it probably does.)  If the program is not
resetting it quite often enough, it could run out during normal operation
and cause the symptom of erratic operation at low temperature.

-Mike

'(Fwd) No life from 16c84'
1995\09\29@054136 by Matthew Rowe

flavicon
face
I wrote the listing below and it assembled fine and it runs on the microchip
simulator.
I have programmed the 16c84 with the serial programmer and the code reads back
fine
which confirms that it has been programmed but when I put the PIC in circuit
nothing
happens.
I am holding the MCLR line high and am using a 4MHz crystal with 15p capacitors
to
ground and LEDs on port b outputs.

Is this circuit correct and does the code check out ok? (reset vector etc.?)


Any help would be appreciated. (If I can't get this working, there's not much
hope
for anything more advanced!)

count1  equ     0C
count2  equ     0D
portb   equ     06

       org     0

init
       movlw   0
       tris    portb                   ; set as outputs
       movwf   portb                   ; set portb levels all low

start
       bsf     portb,0                 ; set working reg bit 0 high


rot_L   call    wait
       rlf     portb,same
       btfss   portb,7
       goto    rot_L

rot_R   call    wait
       rrf     portb,same
       btfss   portb,0
       goto    rot_R
       goto    rot_L

; ----------------------------
; wait subroutine
; ----------------------------
wait
       movlw   .4              ; load count1 with decimal 4
       movwf   count1
d1      movlw   .100            ; load count2 with decimal 100
       movwf   count2
d2      decfsz  count2,same     ; decrement and skip next line if zero
       goto    d2              ; if not zero
       decfsz  count1          ; decrement count1 if count2 is zero
       goto    d1              ; do inside loop again if count2 nz
       retlw   00
; ----------------------------

END




--
/\/\att.

1995\09\29@142937 by Kenny Baby

flavicon
picon face
The file TRISA and TRISB are mapped in page 1, you have to go to page
1 via the STATUS register using RP0 and then load the TRIS registers.
Then go back to page 0 and send the port data to either PORTA or PORTBI've seen
things you people wouldn't believe.
Attack ships on fire off the sholder of Orion.
I watched C-beams glitter in the darkness at Tan Hauser Gate.
All those moments will be lost in time,
like tears in rain.
Time to die.

Remember now, watch out for the Fairies......!

1995\09\29@171549 by Jim Scorse

picon face
>Attack ships on fire off the shoulder of Orion.
>I watched C-beams glitter in the darkness at Tan Hauser Gate.
>All those moments will be lost in time,
>like tears in rain.
>Time to die.

Only replicants have seen this as far as I can tell ;-o)

'...no subject...'
1995\09\29@173036 by RAM6%RnD%RnD

flavicon
face
Mike - turns out that you were right about the WDT. In one section of my
code, I have a 1 second delay loop in which I clear the WDT. After leaving
the loop, the WDT postscaler now has 1 second on it. Next I initialize the
serial port and a radio transmitter... call it a fat second and a quarter
before the WDT is cleared again. It seems that lowering the temperature of
the processor really effects the WDT period. I would have sent you a personal
note, but credit should be given where it is due... thanks!

- Rodger

'(Fwd) No life from 16c84'
1995\09\30@171215 by Andrew Warren

face
flavicon
face
You wrote:
>
>I wrote the listing below and it assembled fine and it runs on the
>microchip simulator.
>
>I have programmed the 16c84 .... when I put the PIC in circuit
>nothing happens.
>
>I am holding the MCLR line high and am using a 4MHz crystal with 15p
>capacitors to ground and LEDs on port b outputs.
>
>Is this circuit correct and does the code check out ok? (reset vector
etc.?)
>
> ....
>        movlw   0
>        tris    portb                   ; set as outputs
> ....

Matt:

Ignore the guy telling you to switch register pages; your code will
work just fine.

My guess is that either the oscillator isn't working or that you
haven't turned off the Watchdog Timer.

-Andy

--
Andrew Warren - fastfwdspam_OUTspam@spam@ix.netcom.com
Fast Forward Engineering, Vista, California

1995\09\30@225552 by Newfound Electronics

flavicon
face
{Quote hidden}

Matt,
        The code looks fine. The problem must be in the hardware or to do
with the programmer.

The Xtal/cap combo is right, I use the same.

Try forcing a reset by pulling MCLR low. ( the power up time may be to slow
for the pic's  internal reset) .

Check that the leds are the right way around.

Check the WDT is OFF but even so you still should have a couple of seconds
before reset because the WDT default is maximum setting.

Check that you are loading the right type if hex file into the programmer.
If memory serves, it is possible to load the wrong hex format and
programmers can't detect the error.

If the wrong file type is loaded and accepted, it will program and verify as
being correct.

Quit the programmer, reload it and read the device again, this is the only
way to  test that the programmer is really working. Compare the results
against the program listing.

Good luck, you seem to be on the right track. Everyone has these hassles at
the beginning!

Regards, Jim Robertson

P.S Sorry about the delay, the first reply bounced.



-----------------------------------------------------------------
NEWFOUND ELECTRONICS,  Makers of low cost,
mega featured PIC programming tools.
.....newfoundspamspam.....ne.com.au
------------------------------------------------------------------


'(Fwd) No life from 16c84'
1995\10\02@100435 by Scott Stephens
flavicon
face
>To: pic microcontroller discussion list <PICLISTKILLspamspamEraseMEMITVMA.BITNET>
>From: EraseMEstephnss@spam@spam@spam@mail.pyrotechnics.com
>Subject: Re: (Fwd) No life from 16c84
>
>>I wrote the listing below and it assembled fine and it runs on the microchip
>>simulator.
>>I have programmed the 16c84 with the serial programmer and the code reads back
>> fine
>>which confirms that it has been programmed but when I put the PIC in circuit
>> nothing
>>happens.
>>I am holding the MCLR line high and am using a 4MHz crystal with 15p
capacitors
{Quote hidden}

PC's serial port, the latest MPASM assembler, which gave me 22 errors when I
assembled your code.
>I made the following changes:
>;**************************************************************************
*****
>LIST           p=16C84 ;target processor                      ;Tell MPASM you'v
e
got a C84 PIC
>_CP_OFF                      EQU     H'3FFF'                   ;code
protect off
>_PWRTE_ON                    EQU     H'3FFF'                   ;Power on
timer on
>_WDT_OFF                     EQU     H'3FFB'                   ;watch dog
timer off
>_XT_OSC                      EQU     H'3FFD'                   ;crystal
oscillator
>__CONFIG       _CP_OFF & _PWRTE_ON & _WDT_OFF & _XT_OSC       ;configure direct
ive
>
>same   equ     1        ;VERY IMPORTANT! put variables in register, NOT W.
>;**************************************************************************
*****
>I used a 32KHz quartz crystal and watched a few LED's scan back & forth.
Pretty cool :)
>At 4 MHz with your timer parameters, they would all appear partialy lit.
>
>

'(no subject)'
1995\10\06@182601 by queens-belfast.ac.uk%UKACRL.bitnet

flavicon
face
Robin Abbott <@spam@fs34spamspamKILLspamDIAL.PIPEX.COM> said;
> I am interested in John loch's message about C compilers. Having
> written a C compiler myself (many years ago for a Z80), then I
> became very aware of the need for masses of stack space! I just
> can't see this on any of the PIC's in the 5X,6x,7x series unless
> perhaps the 74 offers enough RAM.

I think that in the case of PICs the benefits of a C compiler
are very limited especially with regard to size of code. One
could produce a C interpreter with some intermediate 'P' code
much like your ETI PIC Basic project though, which needs extra
ram but is ideal for projects where timing isn't too critical.
I'm a firm believer in a good set of assembler macros ;-)

Speaking of Basic, do you have any intentions of slapping
a GNU copyleft license on your PIC Basic ?

Would anyone be interested in;

o An alternative PIC assembler (primarily for Unix-like operating systems)
o A PIC Basic interpreter

I don't have either of these I may add but I could be persuaded
to spend a *small* amount of time on them. All work would be GNU licensed.
Alternatively if anyone else wants to do it please go ahead !

--
John P

1995\10\06@233343 by Stuart Allman

flavicon
face
> o An alternative PIC assembler (primarily for Unix-like operating systems)
> o A PIC Basic interpreter
>
>I don't have either of these I may add but I could be persuaded
>to spend a *small* amount of time on them. All work would be GNU licensed.
>Alternatively if anyone else wants to do it please go ahead !
>


I'd like to see an assembler for my PIC START kit for unix.  Would this be
distributed
as source code or binary?  What Unix platforms would be supported?  I'd like
to see the tools for Solaris and Linix.

Stuart Allman
spamBeGonestudioRemoveMEspamEraseMEhalcyon.com

'ISP Pinout!'
1995\10\16@202407 by Don McKenzie

flavicon
face
On Mon, 16 Oct 1995, Falstaff wrote:

> Is there a standard pinout for the ISP connector?  Would be nice if
> everyone used the same pinout, so that a standard programmer & cable
> could be used -- much like the background debugger connector Motorola
> specifies for the 683xx series.
>
> I use a 5-pin SIL header (0.1" pin spacing) with the following pinout
>         1       VCC
>         2       /MCLR VPP
>         3       RB6
>         4       RB7
>         5       GND

I agree Frank, but of course our pinouts don't.

The pinout I use was published in Circuit Cellar in an article by Dr Russ
Reiss some time ago, and this is the setup I now use for In-circuit
programming for my programmer. A 10 pin header is used. This not only
allows for circuit isolation but also 10 pin IDC crimp connectors and flat
ribon cable can be used for board interconnection.

1 VDD       2 VDD  User
3 MCLR      4 MCLR User
5 RB7       6 RB7  User
7 RB6       8 RB6  User
9 GND      10 GND

You will notice that only the position of RB6 and RB7 are reversed.

The 10 pin header is found on both the programmer board and the target board.
Test links are used to re-connect the circuit when the programming cable
is removed. A full run-down on this can be found on my Promo Disk.

I have now convinced several designers to use this pinout. It would
really help when using adapter boards too!!

Don...

 Low Cost DIY PCB's for PICs & COM1/LPT1 PC I/O Interface Kits    ;!
 Don McKenzie. 29 Ellesmere Cres., Tullamarine. 3043 Australia    ;@
 Tel +61 3 9338 6286 Mobile  +61 19 939 799 RemoveMEdonmckKILLspamspamRemoveMEtbsa.com.au    ;#
 Check My Promo Disk at http://rasi.lr.ttu.ee/~sis/mirror/don/    ;$
 Type: 'finger TakeThisOuTdonmckspamtbsa.com.au|more'  for more information.

1995\10\17@042831 by Don McKenzie

flavicon
face
> On Mon, 16 Oct 1995, Falstaff wrote:
> Is there a standard pinout for the ISP connector?  Would be nice if
> everyone used the same pinout, so that a standard programmer & cable
> could be used -- much like the background debugger connector Motorola
> specifies for the 683xx series.
>
> I use a 5-pin SIL header (0.1" pin spacing) with the following pinout
>         1       VCC
>         2       /MCLR VPP
>         3       RB6
>         4       RB7
>         5       GND

I agree Frank, but of course our pinouts don't.

The pinout I use was published in Circuit Cellar in an article by Dr Russ
Reiss some time ago, and this is the setup I now use for In-circuit
programming for my programmer. A 10 pin header is used. This not only
allows for circuit isolation but also 10 pin IDC crimp connectors and flat
ribon cable can be used for board interconnection.

1 VDD       2 VDD  User
3 MCLR      4 MCLR User
5 RB7       6 RB7  User
7 RB6       8 RB6  User
9 GND      10 GND

You will notice that only the position of RB6 and RB7 are reversed.

The 10 pin header is found on both the programmer board and the target board.
Test links are used to re-connect the circuit when the programming cable
is removed. A full run-down on this can be found on my Promo Disk.

I have now convinced several designers to use this pinout. It would
really help when using adapter boards too!!

Don...

 Low Cost DIY PCB's for PICs & COM1/LPT1 PC I/O Interface Kits    ;!
 Don McKenzie. 29 Ellesmere Cres., Tullamarine. 3043 Australia    ;@
 Tel +61 3 9338 6286 Mobile  +61 19 939 799 spamBeGonedonmckKILLspamspamTakeThisOuTtbsa.com.au    ;#
 Check My Promo Disk at http://rasi.lr.ttu.ee/~sis/mirror/don/    ;$
 Type: 'finger EraseMEdonmck.....spamKILLspamtbsa.com.au|more'  for more information.

1995\10\17@091857 by Newfound Electronics

flavicon
face
>On Mon, 16 Oct 1995, Falstaff wrote:
>
>> Is there a standard pinout for the ISP connector?  Would be nice if
>> everyone used the same pinout, so that a standard programmer & cable
>> could be used -- much like the background debugger connector Motorola
>> specifies for the 683xx series.

Don McKenize replied
{Quote hidden}

You havn't convinced me Don. What is wrong with the above pinouts??

ANSWER. Plug the cable around the wrong way and you blow the s*it (suit?)
out of you PIC and possibly the entire target system!

This is my pinout arrangement used on all my programmers.

1 Vcc
2 Gnd
3 Vpp
4 RB7
5 RB6

Notice if the cable is put the wrong way around that Vpp will still be
correct and you are far less likely, by a  long way,  to damage anything.
If anyone is happy to play "ISP roulette" with their pinouts, I'm ready.

Regards to all ,
Jim Robertson


-----------------------------------------------------------------
NEWFOUND ELECTRONICS,  Makers of low cost,
mega featured PIC programming tools.
spamnewfoundspamne.com.au
------------------------------------------------------------------

'another request!'
1995\10\23@125701 by MARAMI%IREARN.bitnet

flavicon
face
Dear friends,
thanks for your reply to my first request.i found PIC assembler and
simulator in http://www.ultranet.com/biz/mchip but i could not
get them .because our INTERNET line in IRAN is very slow(9600 bps).
so i have a new request.may you treat me kindly and send me these programs
by e-mail? if you have in mind to do this kindness please use uuencode
to change  binary file to ascii for e-mail.
thanks for your kindness and cooperation.
A.Marami
ELECTRONICS engineer
e-mail: maramiSTOPspamspamrose.ipm.ac.ir

'UV EPROM Eraser not Working (was: "Thanks!")'
1995\10\26@223400 by Andrew Warren

face
flavicon
face
Ben L Wirz <blw2STOPspamspamKILLspamCEC.WUSTL.EDU> wrote:

>I just got  eprom eraser today, and I don't think is working.
>Should I be able to see the UV light source when it is on, I know tis
>is bad to look directly into?  It has a dot that is supposed to glow
>when it is working, and is not.  Does is sound like I got a bad unit?
>
>I have a:
>Dataerase II from JDR
>(no timer)

Ben:

Do not, do not, DO NOT look at the bulb.  The fluorescent "dot" is
there for a reason.

As I recall, those Daterase II erasers have a safety-interlock switch
in the top cover to protect you from accidentally turning on the lamp
with the cover open.  My guess is that that interlock is keeping the
thing from turning on.

Make sure that the cover's properly installed in the grooves, and that
it's closed COMPLETELY (you should hear a little click as the interlock
engages), then try it again.

-Andy

--
Andrew Warren - @spam@fastfwd.....spamspamix.netcom.com
Fast Forward Engineering, Vista, California

'FTP by mail. (was: another request!)'
1995\10\27@162336 by Sheldon Ward

picon face
At 08:18 PM 10/23/95 +0330, you wrote:

>simulator in http://www.ultranet.com/biz/mchip but i could not
>get them .because our INTERNET line in IRAN is very slow(9600 bps).
>so i have a new request.may you treat me kindly and send me these programs
>by e-mail? if you have in mind to do this kindness please use uuencode
>A.Marami

There are many computers around the world to do just that!  They're called
FTP by Mail servers.  One is at spamftpmail.....spam.....SunSITE.Unc.EDU, but you should use
one that is close to you.  You tell it (via email) where the file is and it
will get the file and email it to you.  Easy to use.  Some sites have long
waiting lists but others are very quick.

Try it out!

Later,

Sheldon
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*                                                                   *
* Sheldon.....spamDirect.Ca            In beautiful Langley, B.C., Canada   *
*                                                                   *
* The opinions expressed herein do not necessarily reflect my own.  *
*                                                                   *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

'application notes'
1995\10\30@051051 by MARAMI%IREARN.bitnet

flavicon
face
Dear friends,
I got an app. note from microchip web site(http://www.ultranet.com) whose name is
an593.zip .after unzip,an593.ps file was generated that i could not read it.
Can you help me what can i read this file in dos or windows?
kind regards
A.Marami
electronics engineer

1995\10\30@061643 by Conny Andersson

flavicon
face
At 12.55 1995-10-30 +0330, A Marami:

>Dear friends,
>I got an app. note from microchip web site(http://www.ultranet.com) whose name is
>an593.zip .after unzip,an593.ps file was generated that i could not read it.
>Can you help me what can i read this file in dos or windows?
>kind regards
>A.Marami
>electronics engineer
>

It's a Postscript file, you can send this file to a printer that understands
Postscript. However, I think you can read it if you get the Ghostscript
package for Windows, see below.

... but isn't there a text-only app-note for an593?

-- Conny

---------------------------------------------------------------------------
This is GSWNGUI2                        April, 1993

A Command Line Graphical User Interface for the MS Windows program:

       Ghostscript for Windows   Ver. 2.5.2

Its purpose is to make the use of Ghostscript for Windows more convenient,
and to make its use feasible for the average user.

Ghostscript is a Postscript Interpreter.  It can display, print on inexpensive
printers, and store in graphics image files the Postscript files intended
to be printed on expensive Postscript printers.

This interface makes the use of the MS Windows version of Ghostscript
much easier.

This is Revision 2.  It improves on the interface for Version 1, eliminates
a couple of bugs, and adds multiselect features.

This software is freely redistributable.  It is not to be sold.

Copyright (c) 1993 by   P. Budgell, London, Ontario, Canada
                       KILLspampeterspam_OUTspamengrg.uwo.ca

----------------------------------------------------------------------

The accompanying gswngui.wri is a Windows Write file describing use of the
program.  It can be read under Windows Write, or printed.  It is 6 pages long.

The user will have to get the Ghostscript for Windows software from
the Internet, or from a well stocked BBS.

On the internet, one source of Ghostscript for the PC is:

       wuarchive.wustl.edu

Look under the ftp directory:

       mirrors/msdos/postscript

The Windows version of Ghostscript is gs252win.zip and support files
will be needed as well.  See my documentation.

A good site for Windows software, and where I found gs252win.zip is the
Internet site:

       ftp.cica.indiana.edu

----------------------------------------------------------------------

There will eventually be revisions to Ghostscript.  The software may
or may not work well with new features.


-- Conny


'application notes'
1995\11\01@014258 by MARAMI%IREARN.bitnet
flavicon
face
dear friends,
I have sent this question 2 or 3 days ago,but i did not receive any answer,so
i think maybe you have not receive this question.let me repeat it:
i got an application note from microchip web site(http://www.ultranet.com)whose name
is an593.zip.after unzip this file i got an593.ps file,but i could not read it.
can you help me how can i read this file in dos or windows?
i am looking forward hearing from you in soon.
regards
A.Marami
electronics engineer

1995\11\01@075209 by Robert Schwenke

flavicon
face
an593.ps is a postscript file.  You can print it on a postscript printer or
you'll need a postscript viewer like ghostscript (I think that is what they
call it).  You may be able to do a text-only dump into Word using their
encap postscript import function.

Good Luck

'AN592 APP NOTE'
1995\11\01@214442 by Eric Seeley

flavicon
face
Hi,
>I was interested in doing an frequency counter. Great ! There is an application
>note in the Microchip book (frequency counter, I think the number is an592).
>I read it, and I didn't understand how it works. I thought the best to do is
>to get the file from Microchip and simulated it.
>But, the file was in Postscript. So, I had to type it !
>After simulation, my conclusion is (but perhaps I'm wrong):
> This file can't work !!
> Example: movlw B'10000100' seams to be the instruction to configure the entry
>  port !
>So, my questions are:
> Am I wrong, or some files (or perhaps the most of them) of the Microchip
> book were not tested ? If so, where can I find a list of file tested ?
>
>Thanks for reply
>
>Yves Bergeon
>
>I have come to the same conclussion re AN592, however I am using the "it's
the thought that counts" and used the general idea, i.e. gating the RTCC
(TMR0 on the 'c74, which I'm using) and the use of a I/O port to pull  the
external frequency source low when you are not counting and a fixed software
delay to set the gate period.  I am also interested in inputs from others on
this app note as well as a source for the 3 wire led LT8522.

Thanks, Eric

'Why not EEPROM PICs? (Was: Bulk Buy of 16C84)'
1995\11\02@111754 by Martin Nilsson

picon face
(I hope Microchip folks listen, and correct me if I'm wrong!)  I have
heard the following reasons from Microchip reps:

1. Why not more EEPROM PICs: Microchip's EEPROM technology
requires a lot of silicon area. Other features are not worth trading
off for EEPROM.

2. Why not use more space efficient flash prom technology: Microchip
would have to license such technology from outside, which is not part
of their policy.

3. Micro chip believes few (big) customers are interested in EEPROM.
Allegedly, they use only OTP-versions for volume production. For
development, UV-EPROM are considered enough. The ability to reprogram
in-circuit is considered to be of marginal importance. (At several PIC
seminars I have visited, participants have stressed it would be useful
to be able to reprogram new versions, test programs etc., in
circuit, in particular for SMD PICs, but Microchip has not commented
on this.)

4. Actually, it has turned out that the 16C84 does sell very well, but
Microchip attributes this to the EE-programmable _data_ memory, not
_program_ memory. This interest is ascribed to students and hobbyists
(i.e. not much of a business).

I do hope that Microchip will rethink its strategy regarding
EEPROM. In particular, a 16C73 with EEPROM/Flash PROM would be close
to the ultimate microcontroller, in my opinion. Other companies, for
instance Intel, are now beginning to catch up here.

Martin Nilsson
Swedish Institute of Computer Science    E-mail: spam_OUTmnspamTakeThisOuTsics.se
Box 1263, S-164 28 Kista                 Fax: +46-8-751-7230
Sweden                                   Tel: +46-8-752-1574

{Quote hidden}

'No Subject'
1995\11\02@153524 by barry

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picon face
Suspend Mail
--
---------------------------------------------------------------------------
|The Borg assimilated My Race, and all I got Was a Lousy T-Shirt :
---------------------------------------------------------------------------

'Why not EEPROM PICs? (Was: Bulk Buy of 16C84)'
1995\11\02@221751 by BBoles

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face
    Of course Microchip listens...

    However, we are still a relatively small company and out of the
    1,000,000 things we have to do, program memory EEPROM PIC's are about
    number 736,492.

    Also, when we ask our larger customers (who don't need to get together
    to make bulk buys) what they will pay for a reprogrammable 16C73 as
    opposed to a EPROM 16C73, the answer just isn't the one we want to
    hear.

    Everyone out there really needs to talk to a guy in Taiwan who will
    give his mother and his left nut for a micro that costs 10 cents less.
    The real world can be a scary place!

    Rgds, Brian.                             spam_OUTbbolesTakeThisOuTspamEraseMEmicrochip.com


______________________________ Reply Separator _________________________________
Subject: Why not EEPROM PICs? (Was: Bulk Buy of 16C84)
Author:  Martin Nilsson <EraseMEmnspamBeGonespamKILLspamSICS.SE> at Internet_Exchange
Date:    11/1/95 2:13 PM


(I hope Microchip folks listen, and correct me if I'm wrong!)  I have
heard the following reasons from Microchip reps:

1. Why not more EEPROM PICs: Microchip's EEPROM technology
requires a lot of silicon area. Other features are not worth trading
off for EEPROM.

2. Why not use more space efficient flash prom technology: Microchip
would have to license such technology from outside, which is not part
of their policy.

3. Micro chip believes few (big) customers are interested in EEPROM.
Allegedly, they use only OTP-versions for volume production. For
development, UV-EPROM are considered enough. The ability to reprogram
in-circuit is considered to be of marginal importance. (At several PIC
seminars I have visited, participants have stressed it would be useful
to be able to reprogram new versions, test programs etc., in
circuit, in particular for SMD PICs, but Microchip has not commented
on this.)

4. Actually, it has turned out that the 16C84 does sell very well, but
Microchip attributes this to the EE-programmable _data_ memory, not
_program_ memory. This interest is ascribed to students and hobbyists
(i.e. not much of a business).

I do hope that Microchip will rethink its strategy regarding
EEPROM. In particular, a 16C73 with EEPROM/Flash PROM would be close
to the ultimate microcontroller, in my opinion. Other companies, for
instance Intel, are now beginning to catch up here.

Martin Nilsson
Swedish Institute of Computer Science    E-mail: RemoveMEmnspamBeGonespamspamsics.se
Box 1263, S-164 28 Kista                 Fax: +46-8-751-7230
Sweden                                   Tel: +46-8-752-1574

{Quote hidden}

1995\11\03@020106 by BBoles

flavicon
face
    Of course Microchip listens...

    However, we are still a relatively small company and out of the
    1,000,000 things we have to do, program memory EEPROM PIC's are about
    number 736,492.

    Also, when we ask our larger customers (who don't need to get together
    to make bulk buys) what they will pay for a reprogrammable 16C73 as
    opposed to a EPROM 16C73, the answer just isn't the one we want to
    hear.

    Everyone out there really needs to talk to a guy in Taiwan who will
    give his mother and his left nut for a micro that costs 10 cents less.
    The real world can be a scary place!

    Rgds, Brian.                             TakeThisOuTbbolesKILLspamspam@spam@microchip.com



______________________________ Reply Separator _________________________________
Subject: Why not EEPROM PICs? (Was: Bulk Buy of 16C84)
Author:  Martin Nilsson <.....mnRemoveMEspamSICS.SE> at Internet_Exchange
Date:    11/1/95 2:13 PM


(I hope Microchip folks listen, and correct me if I'm wrong!)  I have
heard the following reasons from Microchip reps:

1. Why not more EEPROM PICs: Microchip's EEPROM technology
requires a lot of silicon area. Other features are not worth trading
off for EEPROM.

2. Why not use more space efficient flash prom technology: Microchip
would have to license such technology from outside, which is not part
of their policy.

3. Micro chip believes few (big) customers are interested in EEPROM.
Allegedly, they use only OTP-versions for volume production. For
development, UV-EPROM are considered enough. The ability to reprogram
in-circuit is considered to be of marginal importance. (At several PIC
seminars I have visited, participants have stressed it would be useful
to be able to reprogram new versions, test programs etc., in
circuit, in particular for SMD PICs, but Microchip has not commented
on this.)

4. Actually, it has turned out that the 16C84 does sell very well, but
Microchip attributes this to the EE-programmable _data_ memory, not
_program_ memory. This interest is ascribed to students and hobbyists
(i.e. not much of a business).

I do hope that Microchip will rethink its strategy regarding
EEPROM. In particular, a 16C73 with EEPROM/Flash PROM would be close
to the ultimate microcontroller, in my opinion. Other companies, for
instance Intel, are now beginning to catch up here.

Martin Nilsson
Swedish Institute of Computer Science    E-mail: KILLspammnspamTakeThisOuTsics.se
Box 1263, S-164 28 Kista                 Fax: +46-8-751-7230
Sweden                                   Tel: +46-8-752-1574

{Quote hidden}

1995\11\03@021334 by BBoles

flavicon
face
______________________________ Reply Separator _________________________________
Subject: Why not EEPROM PICs? (Was: Bulk Buy of 16C84)
Author:  Martin Nilsson <RemoveMEmnspamspamSTOPspamSICS.SE> at Internet_Exchange
Date:    11/1/95 2:13 PM


(I hope Microchip folks listen, and correct me if I'm wrong!)  I have
heard the following reasons from Microchip reps:

1. Why not more EEPROM PICs: Microchip's EEPROM technology
requires a lot of silicon area. Other features are not worth trading
off for EEPROM.

2. Why not use more space efficient flash prom technology: Microchip
would have to license such technology from outside, which is not part
of their policy.

3. Micro chip believes few (big) customers are interested in EEPROM.
Allegedly, they use only OTP-versions for volume production. For
development, UV-EPROM are considered enough. The ability to reprogram
in-circuit is considered to be of marginal importance. (At several PIC
seminars I have visited, participants have stressed it would be useful
to be able to reprogram new versions, test programs etc., in
circuit, in particular for SMD PICs, but Microchip has not commented
on this.)

4. Actually, it has turned out that the 16C84 does sell very well, but
Microchip attributes this to the EE-programmable _data_ memory, not
_program_ memory. This interest is ascribed to students and hobbyists
(i.e. not much of a business).

I do hope that Microchip will rethink its strategy regarding
EEPROM. In particular, a 16C73 with EEPROM/Flash PROM would be close
to the ultimate microcontroller, in my opinion. Other companies, for
instance Intel, are now beginning to catch up here.

Martin Nilsson
Swedish Institute of Computer Science    E-mail: .....mnEraseMEspamsics.se
Box 1263, S-164 28 Kista                 Fax: +46-8-751-7230
Sweden                                   Tel: +46-8-752-1574

{Quote hidden}

1995\11\03@072701 by Don McKenzie

flavicon
face
>      Everyone out there really needs to talk to a guy in Taiwan who will
>      give his mother and his left nut for a micro that costs 10 cents less.
>      The real world can be a scary place!

What is the E-mail address of this guy in Taiwan, I can't get constant
prices or supplies in Australia, and MicroChip offer no alternatives for
me.

I look like chucking in with Ben and friends at this stage.

I could say more but will bite my lower lip for now!!!!!

Don...

 Low Cost DIY PCB's for PICs & COM1/LPT1 PC I/O Interface Kits    ;!
 Don McKenzie. 29 Ellesmere Cres., Tullamarine. 3043 Australia    ;@
 Tel +61 3 9338 6286 Mobile  +61 19 939 799 .....donmckEraseMEspamtbsa.com.au    ;#
 Check My Promo Disk at http://rasi.lr.ttu.ee/~sis/mirror/don/    ;$
 Type: 'finger spamdonmckspam_OUTspam@spam@tbsa.com.au|more'  for more information.

1995\11\03@094426 by Martin Nilsson

picon face
Brian,

>      Of course Microchip listens...
>
>      However, we are still a relatively small company and out of the
>      1,000,000 things we have to do, program memory EEPROM PIC's are about
>      number 736,492.

Small, but doing very well (in at least two senses :-).

>      Also, when we ask our larger customers (who don't need to get together
>      to make bulk buys) what they will pay for a reprogrammable 16C73 as
>      opposed to a EPROM 16C73, the answer just isn't the one we want to
>      hear.

Just for my curiosity, how large is "larger"?

>      Everyone out there really needs to talk to a guy in Taiwan who will
>      give his mother and his left nut for a micro that costs 10 cents less.
>      The real world can be a scary place!
>
>      Rgds, Brian.                             spambboles@spam@spamSTOPspammicrochip.com

I believe the only failsafe way to find out is to produce a version of
the 16C84 (16C84Lite?) where program memory reprogramming is disabled
(i.e. OTP), but EEPROM data memory is intact. Then see how much you
need to differentiate prices for the market to prefer it over the
16C84. If the market switches over to the Lite version for a marginal
price difference, you have a strong argument.

Cheers,
Martin

1995\11\03@135917 by Timothy McDonough DIAL UP1

flavicon
face
> >      Everyone out there really needs to talk to a guy in Taiwan who will
> >      give his mother and his left nut for a micro that costs 10 cents less.
> >      The real world can be a scary place!
>
> What is the E-mail address of this guy in Taiwan, I can't get constant
> prices or supplies in Australia, and MicroChip offer no alternatives for
> me.

I'm not trying to single out anyone in particular but I'm curious to know
whether the people who complain so much about price, etc. sell their own
products, services, labor at bargain basement prices just because the
people who buy from them don't want to pay very much?

When you see low prices like Mot 6805J1A's for <$2 you have to remember
that they're on allocation half the time, they're more difficult to buy
in one's and tens, etc. Considering the overhead involved I doubt if any
manufacturer of mcu's would be in business on the money they make (lose?)
selling one or two pieces to an individual.

I'm not affiliated with Microchip. They're just one of the many suppliers
I deal with in an effort to earn a living for my family.

Tim McDonough

1995\11\03@151639 by Steve Chandler

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face
{Quote hidden}

WHAT!! Are you trying to say they are in it for the.... MONEY!?! Oooh! :)

Steve Chandler
Seiko Communications Systems, Inc.

1995\11\03@173116 by John Bean

flavicon
face
>> >      Everyone out there really needs to talk to a guy in Taiwan who will
>> >      give his mother and his left nut for a micro that costs 10 cents less.
>> >      The real world can be a scary place!
>>
>> What is the E-mail address of this guy in Taiwan, I can't get constant
>> prices or supplies in Australia, and MicroChip offer no alternatives for
>> me.
>
>I'm not trying to single out anyone in particular but I'm curious to know
>whether the people who complain so much about price, etc. sell their own
>products, services, labor at bargain basement prices just because the
>people who buy from them don't want to pay very much?
>
I worked for a company that made garage door openers radios, about 1.2
million units a year. We would let a 40k/year engineer work for three weeks
to eliminate one jumper on a single sided board. At .3 cents each it cost
many thousands of dollars to use that part.

In addition we would let work an extra two or three weeks on a layout just
to get the parts lined up so the head on the automatic insertion machine
did not have to turn. That turn takes about half a second but it works out
to several man-weeks per year of machine time in the quantities we were
doing.

I felt sorry, well sometimes, for the parts manufacturers. We used to beat
them mercilessly. I remember meeting 3 different EEPROM makers on the same
day to try to save a penny a part. Again, a penny is not much, but 1.2
million of them is something to write home about. And in this case we saved
7 of those shiny pennys on each EEPROM.

Our market was extreamly competitive. Eventually, someone was importing a
finished product for less than we could buy the parts for.

Now I am back in my own company doing custom stuff. Usually, it just
doesn't matter how much something costs. Nothing is more important than
time. I have used a MC68HC811E2 at $18.00 each to do a  485 bus keyswitch
box that interfaced a switch and two leds. It was cheaper, on 50 pcs, to
use the $900 worth of parts than it would have been to spend a week
re-writing the serial protocol for a 6805 or PIC.

And as far as allocation, it's part of life in the mass production game.
Saving some cost later is better than never saving it at all. Also, you
schedule say 50,000 pcs a month of something to keep the pipeline moving
and then take bigger sums when they are available.

John Bean

Advanced Telemetry Systems
spamBeGonejrbspamBeGonespam@spam@gate.net

'piclist signoff'
1995\11\04@130556 by Jack Davis

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face
Can someone offer a suggestion on getting disconnected from the list?

Nothing seems to work.

Thanks, Jack

1995\11\04@132711 by Eric Brewer

flavicon
face
>Can someone offer a suggestion on getting disconnected from the list?
>
>Nothing seems to work.
>
>Thanks, Jack
Send the following message to RemoveMElistservRemoveMEspamRemoveMEmitvma.mit.edu:

signoff piclist

Hope it helps,
eric

'FYI - Picstart Design Contest Application Brief No'
1995\11\07@152034 by Harrison Cooper

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I have a copy, since I was actually published !!

Anyway, document is noted as December 1993 / DS030229B

Please note that these are *very* brief application notes created by
the folks in the real world - no code listings, etc.

It would be nice to know who else is on the list that is published,
as there are some interesting ideas shown.

-Harrison Cooper
hcooperKILLspamspamspames.com

'NOON DAY MINISTRY BRINGS FOOD AND DIGNITY TO HOMEL'
1995\11\08@094009 by NOOD DAY MINISTRY

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NOON DAY MINISTRY BRINGS FOOD AND DIGNITY TO HOMELESS


Albuquerque Ministry Makes a Real Difference!

Since 1982, over 500,000 meals have been served to
New Mexico's needy and homeless at Noon Day Ministry in
Albuquerque, New Mexico.  Each Tuesday through Friday, Noon
Day opens its doors to those needing a good hot meal, a
shower, clean clothes, laundry facilities and other basic services
provided by caring Christian people who help give dignity to
the homeless.  Noon Day's name is taken from Isaiah 58:10
"If you spend yourself on behalf of the hungry ... your night will
become like the Noon-Day."

Noon Day Ministry also provides transitional housing assistance
for selected families with children who have no home and few
belongings.  Assistance may include help with rent, utilities,
donated furniture, appliances, transportation and counseling.  It is
Noon Day's hope to eventually assist it clients graduate to a job
and a place to live.

Reverend Billy Graham is among those who have applauded
Noon Day's charitable work.  President George Bush
commended Noon Day's outstanding record of community
service saying "Efforts such as yours are evident that the
values of duty, acceptance of personal responsibility,
commitment, and a respect for every individual ... remain firmly
embedded in the American character.  I commend you for
making a difference in the life of your community."

Noon Day Ministry accepts no government assistance.  You can
help support the fine efforts of the Noon Day volunteers by
sending a tax-deductible contribution to Noon Day Ministry,
PO Box 25451, Albuquerque, New Mexico  87125.

For more information, call Noon Day at (505) 247-3611.

'DTMF and Weeder Technologies'
1995\11\10@112454 by David G. Schmidt

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face
For those that asked, Here's Weeder Technologies address and #

Weeder Technologies
PO Box 421
Batavia, OH 45103
(513) 752-0279

He has these PIC based items in his catalog
DTMF decoder/logger
Telephone caller ID
Caller Block
Telephone call restrictor
PIC based 50Mhz Autoscale Frequency Counter
Electronic Message Module

The DTMF decoder/logger code can be downloaded from the Popular
Electronics BBS.  It and the 50Mhz Freq Counter were projects in older
issues.

--------------------------------------------
( Dave Schmidt       DSchmidt Technologies )
( spam_OUTdschmidt@spam@spamrain.org     Ventura, CA        )
( Own an FME? ->finger TakeThisOuTdschmidtspam_OUTspamrain.org   )
--------------------------------------------

'DTMF and Weeder Technologies (fwd)'
1995\11\10@141500 by David G. Schmidt

flavicon
face
My Third Attempt To Post This!!
For those that asked, Here's Weeder Technologies address and #

Weeder Technologies
PO Box 421
Batavia, OH 45103
(513) 752-0279

He has these PIC based items in his catalog
DTMF decoder/logger
Telephone caller ID
Caller Block
Telephone call restrictor
PIC based 50Mhz Autoscale Frequency Counter
Electronic Message Module

The DTMF decoder/logger code can be downloaded from the Popular
Electronics BBS.  It and the 50Mhz Freq Counter were projects in older
issues.

--------------------------------------------
( Dave Schmidt       DSchmidt Technologies )
( KILLspamdschmidt.....spamTakeThisOuTrain.org     Ventura, CA        )
( Own an FME? ->finger TakeThisOuTdschmidtEraseMEspamRemoveMErain.org   )
--------------------------------------------

'Anyone know a source for stepper motors?'
1995\11\16@092735 by Mike Goelzer

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face
       I'm interested in using a PIC to control a stepper motor.  The best
documentation I've found is a Parallax BASIC Stamp app. note that talks
about interfacing a Stamp to a stepper (and since the stamp is really just a
PIC in disguise, I figure its close enough).  Anyway, in that app note the
writer has used an "Airpax" stepper, which I cannot locate..  Digikey only
sells one kind of stepper, and these do not meet my specs.  So I was
wondering if anyone knows where I might find a wider array of steppers? (I
am also sort of hoping that someone from Parallax who reads this list will
know where the author of Stamp app. note number 6 got his motor and will
tell me.)

Thanks for any info.

-mike
--
Mike Goelzer
<spam_OUTmgoelzerRemoveMEspam.....us.net>

1995\11\16@122554 by Michael Robin

flavicon
face
Mike Goelzer wrote:

 So I was
> wondering if anyone knows where I might find a wider array of steppers? (I
> am also sort of hoping that someone from Parallax who reads this list will
> know where the author of Stamp app. note number 6 got his motor and will
> tell me.)

Hey Mike,
       The writer of App. note #6 is Scott Edwards.  He can be reached at
(502) 459-4802.

       Michael J. Robin
       Parallax Support

1995\11\16@152826 by Don McKenzie

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face
On Thu, 16 Nov 1995, Michael Robin wrote:

> Mike Goelzer wrote:
>
>   So I was
> > wondering if anyone knows where I might find a wider array of steppers? (I
> > am also sort of hoping that someone from Parallax who reads this list will
> > know where the author of Stamp app. note number 6 got his motor and will
> > tell me.)
>
> Hey Mike,
>         The writer of App. note #6 is Scott Edwards.  He can be reached at
> (502) 459-4802.

And a range of the Airpax steppers mentioned in Application note 6,
will be found in the All Electronics Corp catalogue. (US).
Try whttp://www.allcorp.com/allcorp/

They sent us a free catalog (Australia) after our E-mail request,
needless to say we have purchased and received our first order including
some of these Airpax steppers which I must find the time to hook up to a
PIC.

This outfit has heaps of 'surplus' goods. Well worth getting the catalog!

Don...

 Low Cost DIY PCB's for PICs & COM1/LPT1 PC I/O Interface Kits    ;!
 Don McKenzie. 29 Ellesmere Cres., Tullamarine. 3043 Australia    ;@
 Tel +61 3 9338 6286 Mobile  +61 14 672 127 spamdonmckKILLspamspamKILLspamtbsa.com.au    ;#
 Check My Promo Disk at http://rasi.lr.ttu.ee/~sis/mirror/don/    ;$
 Type: 'finger spamdonmckspam_OUTspamtbsa.com.au|more'  for more information.

1995\11\16@181312 by Carl Connett

flavicon
face
> From:          MAIL@CSERVE {INTERNET:STOPspammgoelzerspam_OUTspamspamBeGoneUS.NET} (Mike Goelzer)
> To:            MAIL@CSERVE {INTERNET:spam_OUTPICLISTspamspamBeGoneMITVMA.MIT.EDU} (Multiple
recipients of list PICLIST)
{Quote hidden}

Have you tried Edmund Scientific?  I seem to remember seeing some in
there.  Another option is to try re-sale catalogs or salvage catalogs
(ummm...of course, I can't think of the name of the one I purchased
from recently...  anyone know of a good one?)  By the way, I'm just
learning about stepper motors and would like to know how your
experience goes.


Carl Connett
Manufacturing Services
DaySpring Cards
PO Box 1010
Siloam Springs, AR  72761
Phn: 501.549.9251
Fax: 501.524.8813
mhs:carlc@outreach (compuserve)
EraseMEcarlcRemoveMEspamoutreach.mhs.compuserve.com (internet)

mhs:carlc@outreach (compuserve)
.....carlcspamspam_OUToutreach.mhs.compuserve.com (internet)

1995\11\17@200116 by John Barrowman

flavicon
face
Hi there!

Sorry I don't have the info you thirst for but I don have a phone number so
you can extract the info from the horses mouth. Scott Edwards (520) 459 4802.

John

'PICLIST Digest - 23 Nov 1995 to 24 Nov 1995'
1995\11\25@093611 by David Baker

flavicon
face
> From:    Nick Howard <@spam@CHP3HOWARNJEraseMEspamspamNTU.AC.UK>
> Subject: Re: PIC Textbook
>
> Does anyone know of a supplier of Scott Edwards PIC sourcebook in the UK???

You can order directly from Scott - I received mine in Malaysia a couple of
days after placing an order by email.

Dave
--
-------------------------------------------------------------------------
|       David Baker        |  Internet   ID (home) - davidTakeThisOuTspamKILLspambaker.pc.my  |
|   Electronics Engineer   |  Internet   ID (work) - RemoveMEdavidTakeThisOuTspamgmetra.po.my |
|                          |  Fax                  - 60-3-2612870       |
|  Kuala Lumpur, Malaysia  |  Compuserve ID        - 70461,2360         |
-------------------------------------------------------------------------

'Oscillator pinouts'
1995\11\28@022342 by Mark G. Forbes

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face
I saw the reply, but let's get a little more exact, here.

Pin 1: has a dot; no connection
Pin 7: ground
Pin 8: output, typically square wave, rail-to-rail
Pin 14: power, +5.0VDC (VCC)

There are also half-size oscillators, in an 8-pin-DIP
sized package. Same sort of layout, just shorter.

Pin 1: dot, no connection
Pin 4: ground
Pin 5: output
Pin 8: power

Power and ground are laid out just like on standard logic
parts; lower left corner is ground, upper right corner is
power, with the part oriented pin 1 toward the top.
@spam@forbesmSTOPspamspampeak.org
KC7LZD
Mark G. Forbes
R & D Engineer
Acres Gaming, Inc.
815 NW 9th Street
Corvallis, OR 97330
(541) 753-0553 x324
(541) 753-7524 fax
"I am the person my parents warned me about."


'PIC Postscript Application notes'
1995\12\01@114541 by Tommy Brown
flavicon
face
Hi, when I started looking on the net, for info on PICs, I found that most
app notes were in either .ps or .pdf file format.  I read, in piclist digest,
that Marami, was asking question on how to read ANXXX.PS (Postscript files).
I have tried to send this info to him directly, but his e-mail address is
not correct and keeps getting bounced back.

Since this info is relevant to PIC data sheets, I am posting this to piclist.

The easiest way to get viewer/printer for PIC anxxx.ps files, is to retrieve
Aladdin Ghostscript, and Ghostview.  These allow you to print the files using
a non postcript printer.  You must have ghostscript to run ghostview, be
prepared for a lot of files!  (divide 64k into 3500k to get some idea of how
much E-Mail you will get)

You can send commands to TakeThisOuTftpmailTakeThisOuTspamRemoveMEftp.sunet.se, which is closer to people
overseas than the US ftpmail locations, and a lot less traffic.

That is how I retrieved my ghostscript and ghostview.  The ftpmail server
will get any ftp file, uuencode and send to you as 64k e-mail sections!

If you have problems send email to spam_OUTftpmailspamspam.....ftp.sunet.se, and in body of
message "help", the ftpmail server will send you info back on proper usage.
Example as follows will retrieve all files needed to run ghostscript and
ghostview on MS-WINDOWS 16 bit system:
--------------------------------------------------------------------------------
       To:ftpmail.....spam@spam@ftp.sunet.se
     From:spamBeGoneusernamespamspam_OUTserver.domain.name.
  Subject:
       Cc:
      Bcc:
Atachments:
--------------------------------------------------------------------------------
reply-to EraseMEusername.....spamserver.domain.name.
open ftp.cs.wisc.edu
cd ghost/aladdin
get gs333ini.zip
get gs333win.zip
get gs333fn1.zip
cd ghost/rjl
get gsview13.zip
quit
----------------------------------------------------------------------------
****************************************************************************
If you want files for win32, change the "get gs333win.zip to "get gs333w32.zip"
If you want files for ms-dos, change the "get gs333win.zip to "get gs333dos.zip"
If you want files for os/2, change the "get gs333win.zip to "get gs333os2.zip"

If you have non-msdos computer such as MAC/SUN use the base address:

ftp://ftp.cs.wisc.edu/ghost

Look for read.me files which tell you where those particular ghostscript files
are located.
****************************************************************************
regards


********************************************************************************
* Tom Brown
E-Mail:spamtombrownKILLspamspam@spam@indo.net.id  *
* Bumi Karang Indah                                Phone: 62-21-7508264        *
* Jalan Karang Asri II,       **************************************************
* Blok C2/#43, Lebak Bulus  *    "If something is worth doing,
*
* Jakarta, Seletan 12440   *           It's worth doing right the first time"  *
* Indonesia               *                                                    *
********************************************************************************

'None'
1995\12\01@154621 by Walter Crauwels

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face
Date    1/12/95
Subject None
From    Walter Crauwels
To      piclist

                     Subject:                              Time:  9:33 PM
 OFFICE MEMO         None                                  Date:  1/12/95
unsubscribe piclist

'Ceramic vs monolithic caps for xtal'
1995\12\01@160745 by David G. Schmidt

flavicon
face
I am looking for a source for physically small 15pF ceramic disc
capacitors for use in the xtal section of a PIC.  The digikey
catalog doesn't have any that are really small, especially as
small as those found in Radio Shack's low capacitance blister pack (3/16"
diameter).
  Digikey did have some small 15pF monolithic ceramic caps that would be
perfect in size.  Can I use these instead?  Will these work at 4Mhz?

Thanks for the help or an leads.

Dave

1995\12\01@211027 by Andrew Warren

flavicon
face
David G. Schmidt <dschmidtspamspamTakeThisOuTRAIN.ORG> wrote:

> I am looking for a source for physically small 15pF ceramic disc
> capacitors for use in the xtal section of a PIC.  The digikey
> catalog doesn't have any that are really small

Dave:

Why not use one of those Panasonic resonators with built-in caps?
Digi-Key sells 4 MHz versions for (I think) about 50 cents apiece.

-Andy

Andrew Warren - RemoveMEfastfwdRemoveMEspamix.netcom.com
Fast Forward Engineering, Vista, California
http://www.geopages.com/SiliconValley/2499

1995\12\02@012123 by Shel Michaels

picon face
In a message dated 95-12-01 18:29:38 EST, Dave wrote:

>
>I am looking for a source for physically small 15pF ceramic disc
>capacitors for use in the xtal section of a PIC.  The digikey
>catalog doesn't have any that are really small, especially as
>small as those found in Radio Shack's low capacitance blister pack (3/16"
>diameter).
>   Digikey did have some small 15pF monolithic ceramic caps that would be
>perfect in size.  Can I use these instead?  Will these work at 4Mhz?
>
>Thanks for the help or an leads.
>
>Dave

A couple of times I've used the Panasonic ceramic resonators with built-in
capacitors available from Digikey as P/N PX400, currently selling at 96 cents
by the each.  Never noticed any problems.  You might try them as a small,
convenient source - unless anyone else has had problems with them????

Shel Michaels

1995\12\02@093138 by reginald neale

flavicon
face
{Quote hidden}

I also use the Panasonic resonators. Much, much easier than trying to
stick tiny little in there. You also need about a 1 Meg resistor in
parallel to get reliable starting, with either a crystal or resonator.
In addition to Panasonic, Murata and others make similar resonators.

Reg


....Reg Neale.............standard disclaimer applies.......
"Ignorance is a renewable resource."    P. J. O'Rourke......

'Noisy PIC'
1995\12\13@074555 by Erik Hermann

flavicon
face
>The controller works well but makes an irrataing buzzing/whinning noise.

Replace the capacitor(s) from the oscillator circuitry.


- Erik

___ Terminate 1.51

'MAX232 PINOUTS & RS252'
1995\12\19@020226 by Newfound Electronics

flavicon
face
>Can anyone send me the pinout for a MAX232 chip?
>TakeThisOuTstevec@spam@spam@spam@rain.org

 C1+ 1   16 Vcc
  V+ 2   15 GND
 C1- 3   14 T1out
 C2+ 4   13 R1in
 C2- 5   12 R1out
  V- 6   11 T1in
T2out 7   10 T2in
R2in 8    9 R2out


>
>Also does anybody know the difference between the MAX232 and MAX252?
>
>Thks Ben
>

The data for the MAX252 in in the '92 MAXIM data book. I do not have it, sorry.
From the summary here's what I can tell.

MAX252  RS232 "ISOLATION" INTERFACE

* Needs no caps,
* Two rx/tx drivers .
* "A" and "B" versions with "B" cheaper because of less isolation (500V vs
1500V).
* 20Kvps rated.
* MAX252  has shutdown and tristate modes. (From this we know they are not
pin compatable)

Sorry for the delay guys, my new MAXIM data book arrived just today. There
are some very sexy parts in it!

Regards

Jim Robertson

1995\12\19@023626 by Steve Childress

flavicon
face
------ =_NextPart_000_01BACDA1.AE5D78A0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit

Got a phone # for ordering a catalog?

----------
From:   Newfound Electronics[SMTP:TakeThisOuTnewfoundspamspamNE.COM.AU]
Sent:   Tuesday, December 19, 1995 1:00 PM
To:     Multiple recipients of list PICLIST
Subject:        MAX232 PINOUTS & RS252

>Can anyone send me the pinout for a MAX232 chip?
>KILLspamstevecKILLspamspamspamBeGonerain.org

 C1+ 1   16 Vcc
  V+ 2   15 GND
 C1- 3   14 T1out
 C2+ 4   13 R1in
 C2- 5   12 R1out
  V- 6   11 T1in
T2out 7   10 T2in
R2in 8    9 R2out


>
>Also does anybody know the difference between the MAX232 and MAX252?
>
>Thks Ben
>

The data for the MAX252 in in the '92 MAXIM data book. I do not have it, sorry.
>From the summary here's what I can tell.

MAX252  RS232 "ISOLATION" INTERFACE

* Needs no caps,
* Two rx/tx drivers .
* "A" and "B" versions with "B" cheaper because of less isolation (500V vs
1500V).
* 20Kvps rated.
* MAX252  has shutdown and tristate modes. (From this we know they are not
pin compatable)

Sorry for the delay guys, my new MAXIM data book arrived just today. There
are some very sexy parts in it!

Regards

Jim Robertson



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1sU=

------ =_NextPart_000_01BACDA1.AE5D78A0--

1995\12\19@201250 by Newfound Electronics

flavicon
face
Steve Childress wrote:

>------ =_NextPart_000_01BACDA1.AE5D78A0
>Content-Type: text/plain; charset="us-ascii"
>Content-Transfer-Encoding: 7bit
>
>Got a phone # for ordering a catalog?
>

Yer, but I don't think Veltek send them outside Australia. Anyway, with
maxim you actually need 4 volumes, 1992/93/94/95 as they don't repeat data
sheets.

What is all this base64 stuff and  how do I decode it? Can Eudora do  it for
me or do I need a special utility?

>
>------ =_NextPart_000_01BACDA1.AE5D78A0
>Content-Type: application/ms-tnef
>Content-Transfer-Encoding: base64
>
>eJ8+IigHAQ

etc, etc

>1sU=
>
>------ =_NextPart_000_01BACDA1.AE5D78A0--
>
>

Regards,

Jim

'PIC-powered metronome'
1995\12\20@045009 by Andrew Kay

flavicon
face
I've just started using PIC devices (in fact, I'm almost entirely green
at any sort of electronics).  Having done "flashing LED" and "buzzing
speaker", I'm ready to build something a little more useful, a digital
metronome.

Does anybody know how to produce a reasonably loud "click" from a
3V battery powered circuit?  I tried sending a square pulse to a
teensy weensy miniature speaker, but it's very quiet.

Programmer Software for Free
============================
I built the 16C84 in-circuit programmer
from the application note AN589 -- it worked perfectly first time. I
have built a rudimentary software user interface for the PC in Turbo C
(using Analog Design Specialists low level code).  With this I can
download .hex files from MPASM directly into the device.  The code
only overwrites locations which require changing, to reduce eeprom
cycles during development.

I'd be happy to release my source code (although it still has some
very rough edges!) if there is demand.

Cheers
Andrew Kay
Sharp Labs Europe Ltd, Oxford Science Park, Oxford UK, OX4 4GA
spamBeGoneAndrew.KayKILLspamspamsharp.co.uk  Tel:+44 1865 747711 FAX:+44 1865 747717

1995\12\20@045009 by Andrew Kay

flavicon
face
I've just started using PIC devices (in fact, I'm almost entirely green
at any sort of electronics).  Having done "flashing LED" and "buzzing
speaker", I'm ready to build something a little more useful, a digital
metronome.

Does anybody know how to produce a reasonably loud "click" from a
3V battery powered circuit?  I tried sending a square pulse to a
teensy weensy miniature speaker, but it's very quiet.

Programmer Software for Free
============================
I built the 16C84 in-circuit programmer
from the application note AN589 -- it worked perfectly first time. I
have built a rudimentary software user interface for the PC in Turbo C
(using Analog Design Specialists low level code).  With this I can
download .hex files from MPASM directly into the device.  The code
only overwrites locations which require changing, to reduce eeprom
cycles during development.

I'd be happy to release my source code (although it still has some
very rough edges!) if there is demand.

Cheers
Andrew Kay
Sharp Labs Europe Ltd, Oxford Science Park, Oxford UK, OX4 4GA
Andrew.Kay@spam@spamKILLspamsharp.co.uk  Tel:+44 1865 747711 FAX:+44 1865 747717

1995\12\20@064914 by Clyde Smith-Stubbs

flavicon
face
> Does anybody know how to produce a reasonably loud "click" from a
> 3V battery powered circuit?  I tried sending a square pulse to a
> teensy weensy miniature speaker, but it's very quiet.

Use this circuit:

                          |+V
                          |
          NPN eg. BC548 | /
                        |/
                    ----|                  /|
                    |   |\|        47uF   / |
                    |   |-\      + | |    | |
                    |      +-------| |----| |  8 ohm spkr
                    |   ||/        | |    | |
From        180     |   |/-             --| |
 PIC -----/\/\/\/\--+---|               |  \|
                        |\              |
          PNP eg. BC558 | \             |
                           |            |
                           +------------
                           |
                           | -V

The emitter follower pair can drive the low-impedance speaker much
better than the PIC port pin. The decoupling capacitor makes sure the speaker
sees an AC signal. IF this is not enough noise, duplicate the emitter
follower, and connect to the other side of the speaker, then drive from
another port pin in anti-phase with the first pin. This will swing twice
the supply voltage across the speaker, peak-to-peak. That should get you about
6dB more noise. If you do that, the capacitor may not be required (but I'd
probably leave it there. Be sure to set both port pins high or low when no
noise is required, to avoid reverse polarizing the capacitor, in this case.)

Also, to maximise the noise from the speaker, try baffling it, or even clamping
it directly onto a hard surface - at some frequencies a small speaker will
radiate better from the back of the speaker than the front. Just sitting in
free air is bad. Also, the larger the speaker the better - small speakers
are inefficient.

On low voltages, the base-emitter voltage drop of the emitter follower is
significant
so you might want to use some other circuit where the load is in the collector
side, but driving the transistors is harder - you can't just connect the bases
together
as in this circuit.

I've tested the above circuit on 5V, and it makes an impressive sound from a 1"
speaker at about 1000Hz - a double-ended version on 3V should be slightly
better.

Happy metrognoming. Where do the best gnomes go to school? The London
School of Eco-gnomics!

--
Clyde Smith-Stubbs       | HI-TECH Software,       | Voice: +61 7 3300 5011
EraseMEclydeRemoveMEspam@spam@hitech.com.au      | P.O. Box 103, Alderley, | Fax:   +61 7 3300 5246
http://www.hitech.com.au  | QLD, 4051, AUSTRALIA.   | BBS:   +61 7 3300 5235
----------------------------------------------------------------------------
FREE! Download our shareware (FREE for noncommercial use) MS-DOS C Compiler!
            Point your Web browser at http://www.hitech.com.au/

1995\12\20@064914 by Clyde Smith-Stubbs

flavicon
face
> Does anybody know how to produce a reasonably loud "click" from a
> 3V battery powered circuit?  I tried sending a square pulse to a
> teensy weensy miniature speaker, but it's very quiet.

Use this circuit:

                          |+V
                          |
          NPN eg. BC548 | /
                        |/
                    ----|                  /|
                    |   |\|        47uF   / |
                    |   |-\      + | |    | |
                    |      +-------| |----| |  8 ohm spkr
                    |   ||/        | |    | |
From        180     |   |/-             --| |
 PIC -----/\/\/\/\--+---|               |  \|
                        |\              |
          PNP eg. BC558 | \             |
                           |            |
                           +------------
                           |
                           | -V

The emitter follower pair can drive the low-impedance speaker much
better than the PIC port pin. The decoupling capacitor makes sure the speaker
sees an AC signal. IF this is not enough noise, duplicate the emitter
follower, and connect to the other side of the speaker, then drive from
another port pin in anti-phase with the first pin. This will swing twice
the supply voltage across the speaker, peak-to-peak. That should get you about
6dB more noise. If you do that, the capacitor may not be required (but I'd
probably leave it there. Be sure to set both port pins high or low when no
noise is required, to avoid reverse polarizing the capacitor, in this case.)

Also, to maximise the noise from the speaker, try baffling it, or even clamping
it directly onto a hard surface - at some frequencies a small speaker will
radiate better from the back of the speaker than the front. Just sitting in
free air is bad. Also, the larger the speaker the better - small speakers
are inefficient.

On low voltages, the base-emitter voltage drop of the emitter follower is
significant
so you might want to use some other circuit where the load is in the collector
side, but driving the transistors is harder - you can't just connect the bases
together
as in this circuit.

I've tested the above circuit on 5V, and it makes an impressive sound from a 1"
speaker at about 1000Hz - a double-ended version on 3V should be slightly
better.

Happy metrognoming. Where do the best gnomes go to school? The London
School of Eco-gnomics!

--
Clyde Smith-Stubbs       | HI-TECH Software,       | Voice: +61 7 3300 5011
RemoveMEclydespamspamEraseMEhitech.com.au      | P.O. Box 103, Alderley, | Fax:   +61 7 3300 5246
http://www.hitech.com.au  | QLD, 4051, AUSTRALIA.   | BBS:   +61 7 3300 5235
----------------------------------------------------------------------------
FREE! Download our shareware (FREE for noncommercial use) MS-DOS C Compiler!
            Point your Web browser at http://www.hitech.com.au/

1995\12\20@202014 by Prashant Bhandary

flavicon
picon face
At 09:46 AM 20/12/95 GMT, you wrote:
>I've just started using PIC devices (in fact, I'm almost entirely green
>at any sort of electronics).  Having done "flashing LED" and "buzzing
>speaker", I'm ready to build something a little more useful, a digital
>metronome.
>
>Does anybody know how to produce a reasonably loud "click" from a
>3V battery powered circuit?  I tried sending a square pulse to a
>teensy weensy miniature speaker, but it's very quiet.
>

Instead of a click, try getting a very short beep - just a few cycles worth.
If the 3V is not enough you could use an H bridge to drive it. Two LM 386s
or something similar should do it.

Prashant
+----------------+  -------------------------------------------------
|                |    Prashant Bhandary
|   +---+        |    Spatial Information Systems Section
|   |   |        |    Roads and Traffic Authority
|   |   |        |    Rosebery NSW 2018, AUSTRALIA
|   |   |        |    Tel:  +61-2-662 5299
|   |   +----+   |    Fax:  +61-2-662 5348
|   |        |   |    Email: STOPspamprashb.....spamrta.oz.au
|   +--------+   |
| Still a newbie |    "2b|!2b" - William Shakespeare
+----------------+  -------------------------------------------------

1995\12\20@214101 by John Payson

flavicon
face
> >Does anybody know how to produce a reasonably loud "click" from a
> >3V battery powered circuit?  I tried sending a square pulse to a
> >teensy weensy miniature speaker, but it's very quiet.
> >
>
> Instead of a click, try getting a very short beep - just a few cycles worth.
> If the 3V is not enough you could use an H bridge to drive it. Two LM 386s
> or something similar should do it.

Actually, I'd suggest sending it a short burst of "random" pulses.  Metronomes
that beep with a definite pitch can be a bother musically if their output is
off-key.  If you use random pulses, the resulting sound would be white or pink
noise, and thus less likely to be bothersome.

Also, for output you could tie one leg of the speaker to a port pin, and
the other to a port pin via a cap.  If both port pins switch simultaneously
in opposite directions you could get +/- 6 volts on the speaker which should
give it a louder drive than merely using a single port pin.

1995\12\20@214722 by John Payson

flavicon
face
> Programmer Software for Free
> ============================
> I built the 16C84 in-circuit programmer
> from the application note AN589 -- it worked perfectly first time. I
> have built a rudimentary software user interface for the PC in Turbo C
> (using Analog Design Specialists low level code).  With this I can
> download .hex files from MPASM directly into the device.  The code
> only overwrites locations which require changing, to reduce eeprom
> cycles during development.
>
> I'd be happy to release my source code (although it still has some
> very rough edges!) if there is demand.

I homebrewed two PIC program softwares myself [one in TC, one in QuickBasic
when I accidentally left the TC one at home].  What do you use for printer
port pins?  I used to use 1=Strobe=D7, 2=Data0=Clock 3=Data1=/MCLR 4=+VPP
[high turns it on] but unfortunately on Toshiba laptops pin 1 is not open-
collector, and pin 14 [my second choice] is open-collector but its readback
register shows the latched value rather than its physical state.  Thus, I
strap 14 and 15, both of which go to D7 on the PIC; 14 is the output, 15 the
readback.  How do you work things?

1995\12\20@224124 by Clyde Smith-Stubbs

flavicon
face
> Also, for output you could tie one leg of the speaker to a port pin, and
> the other to a port pin via a cap.  If both port pins switch simultaneously

The trouble with this is that the output impedance of the port pins is
too high to effectively drive a low-impedance speaker. Either use an
amplifier, an emitter-follower setup like I previously described, or
a higher-impedance speaker. Telephone earpieces work quite well. They
produce a surprising amount of noise.

The random noise approach is good, but if you're outputting a click
consisting of a few cycles, then the actual pitch of the tone is
not going to make much difference, and if there is too much variance
between clicks that would not be good.


--
Clyde Smith-Stubbs       | HI-TECH Software,       | Voice: +61 7 3300 5011
spamBeGoneclydeRemoveMEspamRemoveMEhitech.com.au      | P.O. Box 103, Alderley, | Fax:   +61 7 3300 5246
http://www.hitech.com.au  | QLD, 4051, AUSTRALIA.   | BBS:   +61 7 3300 5235
----------------------------------------------------------------------------
FREE! Download our shareware (FREE for noncommercial use) MS-DOS C Compiler!
            Point your Web browser at http://www.hitech.com.au/

1995\12\22@070349 by Siegfried Grob

flavicon
face
Hi John, Andrew and all interested people,

Andew asked:
> > >Does anybody know how to produce a reasonably loud "click" from a
> > >3V battery powered circuit?  I tried sending a square pulse to a
> > >teensy weensy miniature speaker, but it's very quiet.

Someone answered:
> > Instead of a click, try getting a very short beep - just a few cycles worth.
> > If the 3V is not enough you could use an H bridge to drive it. Two LM 386s
> > or something similar should do it.

John replied:
> Actually, I'd suggest sending it a short burst of "random" pulses.
good idea!
>
> Also, for output you could tie one leg of the speaker to a port pin, and
> the other to a port pin via a cap.  If both port pins switch simultaneously
> in opposite directions you could get +/- 6 volts on the speaker which should
> give it a louder drive than merely using a single port pin.
But why do I have to tie one leg of the speaker to a PIC pin _via a cap_?
It _is_ the advantage of a bridge speaker driver not to need any cap!

For example, have a look at the data sheet of a TDA7052 audio amplifier
(from Philips). The data sheet proudly claims that no external components
are needed (well, except for 1 resistor and 1 big cap for Vdd).
I think this IC could be used as a single-chip solution for the speaker-driver
problem, although it might not be the cheapest way.


Merry Christmas! - Frohe Weihnachten!

Siegfried

1995\12\22@105336 by John Payson

flavicon
face
> > Also, for output you could tie one leg of the speaker to a port pin, and
> > the other to a port pin via a cap.  If both port pins switch simultaneously
> > in opposite directions you could get +/- 6 volts on the speaker which should
> > give it a louder drive than merely using a single port pin.
> But why do I have to tie one leg of the speaker to a PIC pin _via a cap_?
> It _is_ the advantage of a bridge speaker driver not to need any cap!

True it's nice to avoid a cap, but you'll almost certainly need either a cap
or a resistor to limit current, and if you use a cap it will allow a higher
peak current initially, and store current fed to it during one cycle for out-
put in the next.  Thus, assuming an initial steady state with the cap's port
pin high and the other one low, we have [all voltages relative to ground]:

 PIN   CAP  CAP [SPKR] PIN
 3.0   3.0  0.0        0.0

If we switch the high/low on the port pins we then have
 0.0   0.0 -3.0        3.0
[six volts one polarity on the speaker--twice Vdd]

After a little while, the cap will equilibrate to
 0.0   0.0  3.0        3.0

which after another click becomes
 3.0   0.0  6.0        0.0
[six volts other polarity on the speaker--twice Vdd]

So the effect of the cap is to double your peak voltage, though at the
expense of horrendously distorting your frequency response (not an issue
for a metronome producing "clicks")

1995\12\22@161909 by Scott Stephens

picon face
>Does anybody know how to produce a reasonably loud "click" from a
>3V battery powered circuit?  I tried sending a square pulse to a
>teensy weensy miniature speaker, but it's very quiet.
>

Try using a piezo speaker, and hitting it with a train of pulses, say 10
milli-seconds of a 4 KHz (250 uS period) square wave. If its too short to
sound like a tone, it will sound like a click. Drive the speaker with two
port lines (complemented, 180 phase) with an appropriate inductor in
parallel with the piezo, around 100mH, to get a louder signal, or use an
audio step-up transformer. Common piezo's are around .001uF.

>Programmer Software for Free
>============================
...
>I'd be happy to release my source code (although it still has some
>very rough edges!) if there is demand.

I'd like to see it. Thanks.


'No Subject..New PIC programmer from ITU > $130'
1996\03\13@140713 by George Wise
flavicon
face
>Has anyone yet used the new PIC programmer from ITU for $129? It is
>supposed
>to program all PIC controller chips.

>Sorry if this has been brought up before, I'm new to the list.

>Steveo

Steve, I've had the pleasure to use that programmer. ITU is selling it
on behalf of NewFound Electronics in Australia. It is fast, thourogh,
and has many feature that were not on my previous programmer (a
Parallax). It programs all the PIC16 devices. Send to:
@spam@newfoundspamBeGonespamne.com.au for the demo of the software.

A side note. I run OS/2 and initially the software would not run
properly, (interrupts on OS/2 causing the DOS software to miss bytes
when reading from the programmer. No problems were experienced with the
actual programming of any devices). The designer, Jim Robertson
modified the software a bit to accomodate OS/2. ( I had to also modify
some OS/2 DOS settings).

I've not used any other programmers, but if you want a inexpensive,
reliable programmer for the PIC16 devices (all of them), get the WARP3.

George

                     ^
                   /   \
                  /     \
                 / ~   ~ \
                /  0   0  \
               (     o     )
_______________oOo__-----__oOo________________
| George Wise Jr                             |
| spam_OUTgwisespamspamibm.net                              |
| Fax: 210-558-7067                          |
|____________________________________________|

'Novice ADC question'
1996\03\15@234221 by rrose

flavicon
face
I'm attempting to use the A/D circuit described in the "Interfacing
an A/D Convertor" app note.

I think I have everything figured out except for one detail.  The
sensor I'm working with outputs a 20mVDC to 80mVDC range.  From
reading the app note, I believe I need to:

    connect Vin(-) to ground
    connect Vref to a 1VDC source

Is this correct?

Note: I'm using 1 volt because the app note says to keep a 1 volt
difference between Vin(-) and Vref.

Also, is this correct: can't I just put a resistor between my 5VDC
power source and Vref to drop the voltage down to 1VDC?

Thanks in advance for any help,

Richard Rosenheim
spamrrosespamspamspamaccessnv.com

1996\03\19@104323 by Jonathan King

flavicon
face
At 11:40 PM 3/15/96 -0500, you wrote:
{Quote hidden}

It might help to start with the second question first.

Vref = Vdd

 +    Simple
 +    can supply needed current (1mA)
 -    DAC conversion gain varies with Vdd (10%?) - not so good for a ckt
with        .4% resolution
 +    Devices are actually specified this way - you know what you are getting

 However, if your sensor has a ratiometric output ( bridge ckt such as some
 pressure sensors), its output range also varies with Vdd and the - above
can   cancel.


Vref <> Vdd

16C71& 16C74 specs give a minimum Vref of 3.0 volts, with a further
constraint   of less than Vdd.

An easy choice would be to use a LM10 from national.  It contains a voltage
reference and two amplifiers.  The first amplifier is hooked to an internal
reference.  Set up the reference opamp to have an output of 4.00 volts (
gain of 20) and use it to supply Vref to the PIC.


Now, you need to scale your 20-80mV to as close to possible to the full
reference voltage in order to take advantage of all the bits.

For a simple ckt, use the other amplifier in the LM10 as an inverting amplifier.
A gain of 65 with the positive input fed by a resitor divider off Vref (1/51
Vref) should scale the 20mV to 3.9 volts and the 80mv to 0 volts.

Two things:

    1) DEFINATELY double check my calculations,
    2) Full scale on your sensor is Ox00 and zero scale is close to OxFF.

If this isn't quite right for what you need, I hope this gets you started.


Jonathan King


*************************************************************************
Jonathan King        *  Unitrode Integrated Circuits  * spamBeGonekingKILLspamspamKILLspamuicc.com
Phone 603 424-2410   *  7 Continental Boulevard       *
FAX   603 424-3460   *  Merrimack, NH   03054-0399    *
                    *                                *
*************************************************************************

'How to make a processor do nothing until interrupt'
1996\03\19@184821 by Hans-Christian Prytz

flavicon
face
I have a question which probably seems rather simple to those of you
who have used the PIC's for a while.

I need a way to have the processor wait (doing nothing) until an
interrupt from TMR0 occurs. I can't use sleep mode becuse TMR0 stops
when the processor enters sleep mode (right?), so I've tried using a
goto loop calling several NOP's, but this (according to MPSIM)
triggers the watchdog timer.

Does anybody have a suggestion?

--
____________________________________________
|Hans-Christian Prytz                        |
|e-mail: TakeThisOuThans.christian.prytzspamspamlogin.eunet.no |
|homepage: http://login.eunet.no/~hanscpr/   |
|____________________________________________|
"If anything can go wrong, it will!"
"If anything goes wrong, it will do so at
 the worst possible time!"
-- Murphy's 1st and 2nd law.
"Murphy was a damn optimist!!"
-- Any friend of Frank Drebin

1996\03\19@192202 by Eric T. Brewer

flavicon
face
The following should do what you desire:

Loop:
               ClrWDT
               Goto            Loop

Cheers,
eric

At 4:41 PM 3/19/96, Hans-Christian Prytz wrote:
{Quote hidden}

1996\03\20@065209 by Kaurstad, yenyvind

flavicon
face
> I have a question which probably seems rather simple to those of you
> who have used the PIC's for a while.
>
> I need a way to have the processor wait (doing nothing) until an
> interrupt from TMR0 occurs. I can't use sleep mode becuse TMR0 stops
> when the processor enters sleep mode (right?), so I've tried using a
> goto loop calling several NOP's, but this (according to MPSIM)
> triggers the watchdog timer.
>
> Does anybody have a suggestion?

Do you need the watchdog-timer ?
If not I suppose you could disable it using thc control bits.
(I'm not sure whether this is possible on all PIC's, though)


---------------------------------------------------------------
  Oyvind Kaurstad    Phone: Norway+90062116   EraseMEoyvindEraseMEspamhsr.no
   4140 Erfjord     http://www.stud.his.no/~oyvind
              The truth is out there - NOT

'NON PIC QUESTION : PDF format'
1996\03\27@094027 by Harrison Cooper

flavicon
face
First, I'm not getting those annoying messages that say my message
has been posted twice, but on the other hand, I don't see my posts
either.  Are these making it to the list ?

OK, PDF format.  Using Acrobat, I can download and read these.  Appears
to be a scan of a document, or is PDF a postscript defined file ?
In other words, how does one go about making a PDF file that can be
viewed using acrobat ?  Being an Adobe product, I looked at Photoshop
choice of formats to save a scan, but nothing showed up as PDF.
So, anyone know how to do this ?

-Harrison Cooper
spamBeGonehcooperspam_OUTspam.....es.com

1996\03\27@102035 by Martin Darwin

flavicon
face
------ =_NextPart_000_01BB1BC7.0080BF20
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable

To make a PDF document you need the PDF writer that comes with Adobe =
Exchange. The PDF writer is a printer driver that saves the output to a =
file.  So if you are in Word, etc... all you have to do is say print to =
PDF and voila you have a PDF file.
Md

----------
From:   Harrison Cooper[SMTP:spamhcooperspamES.COM]
Sent:   March 27, 1996 9:38 AM
To:     Multiple recipients of list PICLIST
Subject:        NON PIC QUESTION : PDF format

First, I'm not getting those annoying messages that say my message
has been posted twice, but on the other hand, I don't see my posts
either.  Are these making it to the list ?

OK, PDF format.  Using Acrobat, I can download and read these.  Appears
to be a scan of a document, or is PDF a postscript defined file ?
In other words, how does one go about making a PDF file that can be
viewed using acrobat ?  Being an Adobe product, I looked at Photoshop
choice of formats to save a scan, but nothing showed up as PDF.
So, anyone know how to do this ?

-Harrison Cooper
RemoveMEhcooperKILLspamspamKILLspames.com



------ =_NextPart_000_01BB1BC7.0080BF20
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Content-Transfer-Encoding: base64

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------ =_NextPart_000_01BB1BC7.0080BF20--

1996\03\27@104702 by Przemek Klosowski

flavicon
face
  First, I'm not getting those annoying messages that say my message
  has been posted twice, but on the other hand, I don't see my posts
  either.  Are these making it to the list ?

They are unfortunately a feature/bug of the mailing list software.

  OK, PDF format.  Using Acrobat, I can download and read these.  Appears
  to be a scan of a document, or is PDF a postscript defined file ?
  In other words, how does one go about making a PDF file that can be
  viewed using acrobat ?  Being an Adobe product, I looked at Photoshop
  choice of formats to save a scan, but nothing showed up as PDF.
  So, anyone know how to do this ?

Acrobat is a makeshift invention---a generalized, site-independent
Postscript. It is generated by Adobe software called Distiller. The
advantages are that it is easy to produce (any program that can
generate Postscript can, via Distiller, produce PDF; that includes
word processors and printed page scanners). It is thus popular with
unsophisticated companies that recently switched from ASCII BBSes and
are still dazzled by WYSIWYG.

The disadvantages of PDF result from its unstructured nature: in
general it is impossible to automatically extract information from
PDF files, index them, etc. (unlike properly executed SGML/HTML).

       przemek

1996\03\27@111859 by Roger Books

flavicon
face
>  Acrobat is a makeshift invention---a generalized, site-independent
>  Postscript. It is generated by Adobe software called Distiller. The
>  advantages are that it is easy to produce (any program that can
>  generate Postscript can, via Distiller, produce PDF; that includes
>  word processors and printed page scanners). It is thus popular with
>  unsophisticated companies that recently switched from ASCII BBSes and
>  are still dazzled by WYSIWYG.
>
>  The disadvantages of PDF result from its unstructured nature: in
>  general it is impossible to automatically extract information from
>  PDF files, index them, etc. (unlike properly executed SGML/HTML).
>
>          przemek
>

OK people, let's not start a flame war over this again.

PDF - disadvantages: not easily searchable, not hyperlinked, may not work
                    on your platform.

     advantages: can do a search in acroread, prints exactly as original
                 document, not hyperlinked.

Roger (I love my computer, I HATE WITH A PASSION most online documentation
       and feel people that do html based docs should be flogged.  In
       particular I wish Cisco had that #$&% CDROM shoved...)

1996\03\27@123308 by Eric Smith

flavicon
face
> Are these making it to the list ?

Yes.  You have to send some command to the list server if you want to
receive copies of your own posts.

> In other words, how does one go about making a PDF file that can be
> viewed using acrobat ?

You need the commercial version of Acrobat Exchange; the free one is only a
viewer.  There is also something called Distiller that can translate
PostScript into PDF.

Cheers,
Eric

'NON PIC - thanks for PDF info'
1996\03\27@145109 by Harrison Cooper

flavicon
face
Thanks to all that responded both list and privatly.  I agree, this was not
to discuss the merits of pdf, just how to create a pdf document.  I now
have my answers.  Thread closed.
-Harrison

'NON PIC QUESTION : PDF format'
1996\03\27@154307 by Jonathan King

flavicon
face
At 11:17 AM 3/27/96 -0500, you wrote:
>
Well, I can't resist, I'll throw in my 2 cents...


Look at it from a business' point of view.  You have a huge database of
information(datasheets, etc) in Postscript form for your paper-based
marketing materials.

The cost of translating them to HTML in a professional manner is
astronomical, especially for what is an unproven but trendy marketing
medium.  That kind of committment is not going to come quickly.

PDF files allow you to take your files and put them in a format that takes
~1/3 the space of PS for minimal effort.  Now your web page just needs to
consist of a your pages directing someone to the proper data sheet, with
minimal HTML coding.

It means you get your information out on the web NOW, which is much better
for us, and for less effort, which is better for the company


>>  Acrobat is a makeshift invention---a generalized, site-independent
>>  Postscript. It is generated by Adobe software called Distiller. The
>>  advantages are that it is easy to produce (any program that can
>>  generate Postscript can, via Distiller, produce PDF; that includes
>>  word processors and printed page scanners). It is thus popular with
>>  unsophisticated companies that recently switched from ASCII BBSes and
>>  are still dazzled by WYSIWYG.

I'd think that any company that had a BBS a few years ago is probably
more sophisitcated than those that never heard of the Internet until 6 months
ago.


>>  The disadvantages of PDF result from its unstructured nature: in
>>  general it is impossible to automatically extract information from
>>  PDF files, index them, etc. (unlike properly executed SGML/HTML).

But is sure beats trying to use ghostscript on a PS file :-)
{Quote hidden}

*************************************************************************
Jonathan King        *  Unitrode Integrated Circuits  * EraseMEkingspamBeGonespamspamuicc.com
Phone 603 424-2410   *  7 Continental Boulevard       *
FAX   603 424-3460   *  Merrimack, NH   03054-0399    *
                    *                                *
*************************************************************************

1996\03\27@172538 by Don McKenzie

flavicon
face
On Wed, 27 Mar 1996, Harrison Cooper wrote:

> First, I'm not getting those annoying messages that say my message
> has been posted twice, but on the other hand, I don't see my posts
> either.  Are these making it to the list ?

I may have confused some on the list by a previous statment. I think I
put a space between no and repro. It should be one word as shown below:

>set piclist ack norepro

>Your subscription options have been successfully updated. Here are the exact
>settings now  in use  for your  subscription. Please take  a few  moments to
>check that this is indeed what you wanted.

>Subscription options for Don McKenzie <KILLspamdonmckspamTBSA.COM.AU>, list PICLIST:
>Ack=Yes, Mail=Yes, Files=Yes, Repro=No, Header=Short, Renewal=Yes,
>Conceal=No

And it still works. That's the third time I have used it in three weeks.

If you send a 'help' message, it will give you a list of commands that
can be sent.

'info' will order documentation.

Don...

Don McKenzie donmckspam_OUTspamspamtbsa.com.au
DonTronics Tullamarine, Australia
http://www.labyrinth.net.au/~donmck

PIC Programmers starting at $15US, BS1/2 & Alternatives 18/28 PIC proto
PicoSaurus, the 40 pin ETI PIC Basic with 8K EEPROM Free Windows Dev Sys


'novice oscillator questions'
1996\04\03@172057 by Tom Sgouros
flavicon
face
Hello all:

I have been messing about with a PICDEM demonstration board and a 16C74,
getting ready to put together an RS232 device, and I have some questions
about the oscillators and their use.

The board comes with an R oscillator built on it, and you can disable it
with a jumper and install a crystal. The documentation for the board says
the R and C are chosen to give about a 2 MHz oscillator.

Anyway here are the questions:

  1. I measured the actual rate of the RC oscillator, and found it to be
909091 Hz. If I put the scope probe on pin OSC1, I see a sawtooth wave. If
I look on OSC2, I see a more-or-less square wave with the same period as
the sawtooth. If I read my spec sheet, it says the frequency on OSC2
should be 1/4 times what I see on OSC1. What am I doing wrong here?

  2. I bought a 4 MHz crystal and some 22pF capacitors. When I insert
these into the holes provided for their use on the board, I can only find
a (very weak--fractions of a volt peak-to-peak) signal that gives me
around 200 KHz. The signal is much weaker than it was for the RC
oscillator, and doesn't look to me like a very healthy one either. It sort
of has regular spikes, but I wouldn't call it a triangle wave or a
sawtooth. (What shape does an oscillating crystal make?) I gather from
some recent discussion on the subject that not all crystals are created
alike, but shouldn't I at least be able to get close?

Many thanks for your help.

Incidentally, the OSC pins and crystal and caps on the board are arranged
sort of like this:

OSC1=----------------o-------------||-------GND
                    |             C1
                    |
                  crystal
                    |
                    |             C2
OSC2=----------------o-------------||-------GND

This looks pretty normal to me. (But then if I knew what I was talking
about, I wouldn't be posting this query.)

---------------------------------------------------------------------
tomssspamspam@spam@ids.net - 401-861-2831 - 42 Forge Road, Potowomut, RI 02818 USA

1996\04\04@012143 by Andrew Warren

face
flavicon
face
Tom Sgouros <spamBeGonePICLIST.....spamMITVMA.MIT.EDU> wrote:

> 1. I measured the actual rate of the RC oscillator, and found it to
> be 909091 Hz. If I put the scope probe on pin OSC1, I see a
> sawtooth wave. If I look on OSC2, I see a more-or-less square wave
> with the same period as the sawtooth. If I read my spec sheet, it
> says the frequency on OSC2 should be 1/4 times what I see on OSC1.
> What am I doing wrong here?

   Tom:

   You're probably loading down the oscillator with your scope
   probe; the only pin that's safe to look at with any old probe is
   OSC2.

{Quote hidden}

   Yes, but only if you've remembered to program the PIC's
   configuration bits for "XT Oscillator" mode.

   -Andy

Andrew Warren - .....fastfwd@spam@spamix.netcom.com
Fast Forward Engineering, Vista, California
http://www.geocities.com/SiliconValley/2499

1996\04\04@012733 by John Payson

flavicon
face
>    1. I measured the actual rate of the RC oscillator, and found it to be
> 909091 Hz. If I put the scope probe on pin OSC1, I see a sawtooth wave. If
> I look on OSC2, I see a more-or-less square wave with the same period as
> the sawtooth. If I read my spec sheet, it says the frequency on OSC2
> should be 1/4 times what I see on OSC1. What am I doing wrong here?

The act of putting the probe on the active part of the oscillator will
add some capacitive loading and, in the case of an RC oscillator, slow
it down.  While it would seem strange that the OSC2 would be running at
about 1MHz for an RC spec'ed at about 2MHz, it could be that the part is
simply not very accurate or that you didn't measure the OSC2 output freq.
very well (did you measure it, or just eyeball it as being similar to OSC1)?

>    2. I bought a 4 MHz crystal and some 22pF capacitors. When I insert
> these into the holes provided for their use on the board, I can only find
> a (very weak--fractions of a volt peak-to-peak) signal that gives me
> around 200 KHz. The signal is much weaker than it was for the RC
> oscillator, and doesn't look to me like a very healthy one either. It sort
> of has regular spikes, but I wouldn't call it a triangle wave or a
> sawtooth. (What shape does an oscillating crystal make?) I gather from
> some recent discussion on the subject that not all crystals are created
> alike, but shouldn't I at least be able to get close?

Putting the probe on a crystal oscillator, especially on OSC1, will cause
it to run poorly.  Note as well, you must reprogram the PIC's oscillator
configuration fuse when you change oscillator types.  I'd suggest checking
the oscillator type fuse, and also checking oscillator frequency without
loading the crystal [best way to do that is to write a loop to wiggle a port
pin and see how fast the pin wiggles.]

'rc vs xtal - Old Notes become New Again'
1996\04\09@094200 by myke predko

flavicon
face
This morning, I received a whole whack of e-mail from PICLIST, most of it
seemed to be resent from the weekend (which I cleaned up yesterday).

For example, the note below is dated April 5th.

Has anybody else seen this?

Myke
{Quote hidden}

Myke

"We're Starfleet officers, weird is part of the job."

Capt. Catherine Janeway

'Old Notes become New Again'
1996\04\09@101609 by Roger Books

flavicon
face
>  This morning, I received a whole whack of e-mail from PICLIST, most of it
>  seemed to be resent from the weekend (which I cleaned up yesterday).
>
>  For example, the note below is dated April 5th.
>
>  Has anybody else seen this?
>

Don't feel alone, I saw it also.  Kinda Strange.  I've seen this on newsgroups
before but never on a mailing list.

Roger

'rc vs xtal - Old Notes become New Again'
1996\04\09@120904 by Andrew Warren

face
flavicon
face
myke predko <spamPICLISTspamMITVMA.MIT.EDU> wrote:

> This morning, I received a whole whack of e-mail from PICLIST, most
> of it seemed to be resent from the weekend (which I cleaned up
> yesterday).
> ....
> Has anybody else seen this?

Yeah, Myke... It all seems to be coming from mauriciospam_OUTspamTakeThisOuTarne.si, whose
mailreader is (apparently) configured improperly.

-Andy

Andrew Warren - spam_OUTfastfwd@spam@spamRemoveMEix.netcom.com
Fast Forward Engineering, Vista, California
http://www.geocities.com/SiliconValley/2499

1996\04\09@123640 by Todd Peterson

picon face
Deja Vou...
At 09:40 AM 4/9/96 EDT, you wrote:
>This morning, I received a whole whack of e-mail from PICLIST, most of it
>seemed to be resent from the weekend (which I cleaned up yesterday).
>
>For example, the note below is dated April 5th.
>
>Has anybody else seen this?

Alright, who resent the last 50 messages?

===========================================================
*** Developers of the PICPlus(TM) Microcontroller Board ***

Todd Peterson, Computer Engineer   (spamtpetersonspamspamnetins.net)
E-LAB Digital Engineering, Inc.

P.O. Box 246
Lawton, IA 51030-0246
(712) 944-5344

Visit us at: http://www.netins.net/showcase/elab/

E-Mail Now for Your Free PICPlus(TM) Information Packet!
TO: @spam@tpetersonspam_OUTspamnetins.net   (include POSTAL mailing address)
===========================================================

1996\04\09@210017 by Odriozola Belden

flavicon
face
I had the same problem today, hope it gets corrected.

RO

At 09:40 AM 9/04/96 EDT, you wrote:
{Quote hidden}

'Returned mail: User unknown'
1996\04\16@083854 by Roger Books

flavicon
face
Could someone unsubscribe the non-existant user

>     ----- Transcript of session follows -----
>  ... while talking to alisa1.lockheed.com.:
>  >>> RCPT To:<RemoveMEERNSTERemoveMEspamalisa1.lockheed.com>
>  <<< 550 No such AlisaMail user here: Invalid address - ERNSTE
>  550 <KILLspamERNSTE.....spamKILLspamALISA1.LOCKHEED.COM>... User unknown

I'm sure everyone that posts to the list gets a bounce from this guy.

Alternatively, would anyone mind if I unsubscribe this guy?

Roger

'brownout protection'
1996\04\22@143718 by Kevin Rhoades

flavicon
face
Has anyone out there used the brownout protection circuits in AN-522 (figure
6 and figure 7)?.

1996\04\22@150025 by Eric T. Brewer

flavicon
face
At 11:10 AM 4/22/96, Kevin Rhoades wrote:
>Has anyone out there used the brownout protection circuits in AN-522 (figure
>6 and figure 7)?.

Having been down the road before, my question is "Why do you think
you need brownout protection?"

eric

1996\04\22@162633 by Kevin Rhoades

flavicon
face
>At 11:10 AM 4/22/96, Kevin Rhoades wrote:
>>Has anyone out there used the brownout protection circuits in AN-522 (figure
>>6 and figure 7)?.
>
At 11:59 AM 4/22/96 -0700, you wrote:
>Having been down the road before, my question is "Why do you think
>you need brownout protection?"
>
>eric
>
Cheap, unpredictable, already existing power supply located in various and
probably noisy (electrically) locations.  I feel the new processor board I'm
designing for an existing device needs all the help it can get.  Cheap
insurance for a fairly low volume project (<200).

Actually I sorta jumped the gun a little with my question.  I went back over
the older messages posted to the list and found the one that references the
motorola MC34064 device.  I'm still curious though about the circuits shown
though...K.R...

1996\04\23@112125 by Scott Dattalo

face
flavicon
face
I just received Maxim's uP Supervisory Analog Design Guide 5, 7'th edition. One
of the parts
they feature is the MAX809. Packaged in a SOT-23, this device provides proper
power-on
reset and Brownout protection. Prices are about .88 USD for quantities above
2500. One
of the things I found interesting is that they specifically discuss the PIC16CXX
family.
You can reach Maxim at

http://www.maxim-ic.com/


Another device worth considering is the XX1232. Originally this part was made by
Dallas
Semiconductor (DS1232), but now several companies also make pin compatible
versions. This
device has power-on reset protection, brownout protection, and a watch dog
timer. I have
used it with another microcontroller and have had good luck with it.


Scott

1996\04\23@132306 by Ed VanderPloeg

flavicon
face
    Kevin,

    I've evaluated the three circuits in AN-552, and basically they do as
    the book says.  They are cheaper than the MC34064 (max $0.30 instead
    of $0.90) but require certain characteristics from your power supply
    to work reliably.  Figure 5 (the diode, resistors & cap) helps only
    when your power supply is slow to ramp up, it gives zero brown-out
    protection.  Figures 6 & 7 help with the brownout and slow power
    supply ramp up, but use a few too many parts for my liking.  Also, if
    you need hysteresis and/or power-on delays, you need even more parts.

    Basically, before you pick protection, know thy power supply....

    -Ed VanderPloeg


______________________________ Reply Separator _________________________________
Subject: Re: brownout protection
Author:  pic microcontroller discussion list <PICLISTspam_OUTspamspam_OUTMITVMA.MIT.EDU> at
InterNet
Date:    4/22/96 2:22 PM


>At 11:10 AM 4/22/96, Kevin Rhoades wrote:
>>Has anyone out there used the brownout protection circuits in AN-522 (figure
>>6 and figure 7)?.
>
At 11:59 AM 4/22/96 -0700, you wrote:
>Having been down the road before, my question is "Why do you think
>you need brownout protection?"
>
>eric
>
Cheap, unpredictable, already existing power supply located in various and
probably noisy (electrically) locations.  I feel the new processor board I'm
designing for an existing device needs all the help it can get.  Cheap
insurance for a fairly low volume project (<200).

Actually I sorta jumped the gun a little with my question.  I went back over
the older messages posted to the list and found the one that references the
motorola MC34064 device.  I'm still curious though about the circuits shown
though...K.R...

1996\04\24@024909 by gary skinner

flavicon
face
My favorite brownout protection circuit is the Seiko S805xx and S807xx
series.  They come in a lot of different flavors.
All are 3 pins.  Very little current draw.
About .30 usdollars in thousands.

Seiko also makes a really good - low quiscent current 3 terminal regulator.


Hope this helps someone..
Gary Skinner,  Electronic Solutions Inc
Design of custom control circuits
Denver CO  303-469-9322

'(no subject)'
1996\04\29@000625 by David/Wanda Benson

flavicon
face
We would like to join your discussion group.  Can you place us on this
list with the above email address or do you need something further for
this to happen?  Dues, maybe?  Thank you very much.  Wanda Benson

1996\04\29@005818 by Don McKenzie

flavicon
face
On Mon, 29 Apr 1996, David/Wanda Benson wrote:
> We would like to join your discussion group.  Can you place us on this
> list with the above email address or do you need something further for
> this to happen?  Dues, maybe?  Thank you very much.  Wanda Benson
You are on the list now David/Wanda, go for it.

That book you were asking me about, I found Farnell's have it at around
$40US but remember what I said. Cheers Don...

Don McKenzie KILLspamdonmckspam@spam@labyrinth.net.au
DonTronics Tullamarine, Australia
http://www.labyrinth.net.au/~donmck

PIC Basic Compiler available now. PIC Programmers starting at $15US
PicoSaurus, the 40 pin ETI PIC Basic with 8K EEPROM Free Windows Dev Sys


'Free Data Books -- NO LONGER AVAILABLE'
1996\05\03@011053 by Andrew Warren
face
flavicon
face
A new record... It took only two hours to find a home for the data
books.

-Andy

Andrew Warren - @spam@fastfwdRemoveMEspamix.netcom.com
Fast Forward Engineering, Vista, California
http://www.geocities.com/SiliconValley/2499

'No Branch command?'
1996\05\13@133728 by David E. Queen

flavicon
face
I downloaded the PDF format version of the 16c6X and 16c7X chips and
looked under the INSTRUCTION SET SUMMARY and could not find a conditional
branch listed.

How do you write code without a compare or conditional branch?

Also could someone point me to some 16c64 or 16c65 code using to
read and write to an I2C serial eeprom? I need to read/write 440x 6 bytes
, another 100x 6 bytes, and a single byte  data elements to this chip.

Its dumb but for my first project I picked a big one.
Its something we could use at work to get rid of 15  early 70's vintage
descret transistor differential amps, all on individual plug in pc boards,
and a matched set of about 30 oven stabilized log current diodes.

Ever try to keep 20 year old RC timing circuits stable? Some of the wiring is
starting to develop 100k ohm range phantom connections....

All I need to have it do is generate 3 stable exposure times. I plan to
pre-calculate all the 440 possible times and store them in the eeprom.
I also plan to store 100 setups. Its the user interface that makes it
a big project. LCD display, 5 encoders (NO MORE POTS YEAH!), a couple
push buttons and hooking up to 24v relays to connect the thing.


I have taken up too much bandwidth already. Thanks for any help.

1996\05\13@143143 by Roger Books

flavicon
face
There are several versions of the jump command that do a conditional jump
based on the status of several flags.

I'm sure you'll hear more about this from others.

Roger

1996\05\13@150728 by o Soares

flavicon
face
At 12:43 13-05-1996 -0500, you wrote:
>I downloaded the PDF format version of the 16c6X and 16c7X chips and
>looked under the INSTRUCTION SET SUMMARY and could not find a conditional
>branch listed.
>
>How do you write code without a compare or conditional branch?

Hello all (and specially Roger)

Take a close look at the following instructions:

BTFSC   file_register,bit_number        ;test bit, skip if clear
BTFSS   file_register,bit_number        ;test bit, skip if set
DECFSZ  file_register,destination       ;decrement file register, skip if zero
GOTO    _label                          ;absolute jump
INCFSZ  file_register,destination       ;increment file register, skip if zero

All these instructions (except GOTO) skip the next one if the condition is
satisfied. Other jumps can be made by direct manipulation of PCL and/or PCLATH.
Since the status flags are also a file register, the conditional jumps can
be made
using the instructions above. Some examples:

_Example1:
       MOVF    AFileReg,F                              ;setup condition
flags (AFileReg unchanged)
       BTFSS   STATUS,Z                                ;test zero flag,
skip if set
       GOTO    _AFileReg_IsNotZero                     ;not set, AFileReg<>0
_AFileReg_IsZero:
       ;code to execute if AFileReg=0
_AFileReg_IsNotZero:
       ;code to execute if AFileReg<>0


_Example2:
       MOVLW   AValue                                  ;load W with some value
       ADDWF   AFileReg,F                              ;add W with AFileReg
(AFileReg=AFileReg+W)
       BTFSC   STATUS,C                                ;test carry, skip if
not set
       GOTO    _Overflow                               ;carry is set, go
handle overflow
_NotOverflow:
       ;code to execute if AFileReg+AValue<=255
_Overflow:
       ;code to execute if AFileReg+AValue>255

Comparing is done with the SUB instructions and then testing the Z and C flags.
Note that the examples above are true for the 16CXX PICs. I don't know much
about
the other ranges (16C5X and 17CXX)

Hope this helps (a bit).

Fernando Soares

1996\05\13@151126 by rdmiller

picon face
On Mon, 13 May 1996, Roger Books wrote:
> There are several versions of the jump command that do a conditional jump
> based on the status of several flags.

Maybe he's talking about the Parallax pseudo-8051 assembler.  <blech>

Actually, in PIC-native code there are no CONDITIONAL branch
commands.  There are however several conditional "SKIP" commands.

The idea is that you'd usually follow the conditional skip with a
"goto" command, which would be skipped if the condition isn't met.

You get the same effect but you have to think a little differently
if you want to optimize the code.

Rick Miller

1996\05\13@153404 by Roger Books

flavicon
face
Sorry, please ignore anything I say (including this if you want to.)

I'm trying to use 80x86 stuff on PIC's, well, that's even, I've tried to
use PIC assembly on 68K.

Roger
(As I shoot myself in the foot, yet again. :(

'novice xtal freq question'
1996\05\15@142702 by David E. Queen

flavicon
face
I will be using a 16c65 and need to talk to an I2C eeprom and generate
a interrupt for timing every o.5 ms. I want the output to be accurate +/-
1 ms. I think the code that will be driven by the interrupt will be about
100 instructions. or about .1ms at 4mhz.

I have been going back and forth trying to weigh the pro's and con's
of running at 4mhz or 20mhz. I will be using the windowed parts so
20mhz is not a problem, but I am still weeding through the data sheets,
learning assembler and so forth and would like input from someone how
has maybe done something like this as to what I may be overlooking.
For example is there a certain frequency for the oscillator that if you
go over it makes I2C on a 16c65 more difficult to use?

I am sorry if this is a RTFM type question. I am reading them, but I
am also trying to figure out all they mean. I also live in an area of
Kansas where I have to mail order everything and would like to get some
parts comming to start working on it.

'TMR1 still no luck!'
1996\05\16@145533 by Xaq

flavicon
face
I am ready to pull my hair out!  I can not figure out what is wrong.  It
should be real simple and I am sure I missing something real stupid. When I
run the following code, all I get is the one test beep. I hate to post code
and say "Here, fix it", but I don't know what else to try.  And sorry to
those MPASM users, I use the parallax assembler.


       DEVICE  PIC16C74,HS_OSC,WDT_OFF,PROTECT_OFF
  org     00h            ; start vector
  goto    Start
  org     04h            ; interrupt vector
  goto    ServiceInterrupts


       ; there are a bunch of variable definitions here
       ; (I din't think you needed to see those)


Start

       call    ClearRam        ; clear all ram
       call    InitPorts       ; initialize ports
       call    beep            ; beep for half a second, a test beep
       clrf    PIR1
       mov     INTCON,#11000000b
       mov     T1CON, #00100001b
       mov     PIE1,  #00000001b
       mov     TMR1H, #11111111b
       mov     TMR1L, #00000000b ;set to interrupt after 256*4 inst cycles
:loop   goto    :loop           ; wait for int

ServiceInterrupts
      call wait                ;adds delay so that you can hear the two beeps
      call beep
      clrb     TMR1IF           ;clear interrupt flag
      retfie

; the other routines are down here, such as ClearRam,Beep ...
; I am sure those routines work.

Thanks

Zach

1996\05\16@151200 by Adrian Clinciu

flavicon
face
>
>
>        DEVICE  PIC16C74,HS_OSC,WDT_OFF,PROTECT_OFF
>   org     00h            ; start vector
>   goto    Start
>   org     04h            ; interrupt vector
>   goto    ServiceInterrupts
>
>
>        ; there are a bunch of variable definitions here
>        ; (I din't think you needed to see those)
>
>
>Start
>
>        call    ClearRam        ; clear all ram
>        call    InitPorts       ; initialize ports
>        call    beep            ; beep for half a second, a test beep
>        clrf    PIR1
>        mov     INTCON,#11000000b
--------------------------^


This is EEPROM interrupt enable bit. Try to set bit 5.

Enjoy!

1996\05\16@175812 by Jim Main

flavicon
face
At 12:00 PM 16/05/96 GMT, you wrote:
beep
>        clrf    PIR1
>        mov     INTCON,#11000000b
>        mov     T1CON, #00100001b
>        mov     PIE1,  #00000001b
>        mov     TMR1H, #11111111b
>        mov     TMR1L, #00000000b ;set to interrupt after 256*4 inst cycles
>:loop   goto    :loop           ; wait for int

You forgot to set STATUS,RP0 for PIE1 register - it's in register bank 1 !!

eg.

       bsf     STATUS,RP0
       movlw   b'00000001'
       movwf   PIE1
       bcf     STATUS,RP0

'P-N PhotoVoltaic Anomalies'
1996\05\24@141823 by rdmiller

picon face
On Fri, 24 May 1996, Przemek Klosowski wrote:
> IT couldn't have been the thermal radiation: red glow would mean
> several hundred degrees C, and neither semiconductor nor bondings
> nor packaging would survive that.
>
> The red glow results from carrier recombination (LED mechanism) in
> forward-polarized substrate p-n junction. [...]

I've also seen LEDs used as photodetectors using the same concept,
but in reverse of course.  They're not the greatest, but it works
in a pinch... and they come with that handy little lens built in!

Rick Miller

'Cannot read Microchip PDF files!'
1996\05\28@025026 by Onat Ahmet

flavicon
face
Hi!

I'm new to this group, and have just purchased a PIC16C84.
I live in Japan, so all the data sheets that came with it
are in Japanese. Not really convenient. OK, download the
datasheets from Microchip www site. Unfortunatley, when
I do so, my acrobat reader (for Windoze) says they have been
damaged, are being fixed, and then says that they are password
protected...

I download the files using Netscape V2.0, on UNIX. In Microchip
www site, it says that you should set up Netscape to successfully
download the .pdf files, but my version of Netscape does not
seem to have the necessary setup options...

Can anybody help?

Thanks in advance...

PS: I am new to the PIC series, but not to microprocessors, computers
etc.

PPS: An ftp site that has the Microchip www site documents would be
just fine.


| Ahmet ONAT  Kyoto Univ. Japan                                 |
| E-mail    : onat@spam@spamEraseMEkuee.kyoto-u.ac.jp                           |
| WWW page  : http://turbine.kuee.kyoto-u.ac.jp/staff/onat.html |
|             My 6 leg walker, RC airplanes & more in home page |

'Cannot read Microchip .pdf-> solved...'
1996\05\28@032838 by Onat Ahmet

flavicon
face
Greetings;

I just sent a posting to this list stating that I could not read
the PDF files from the Microchip www site. I solved the problem.

Thanks for your atention, and sorry to lose bandwidth...

| Ahmet ONAT  Kyoto Univ. Japan                                 |
| E-mail    : spam_OUTonatspam_OUTspamRemoveMEkuee.kyoto-u.ac.jp                           |
| WWW page  : http://turbine.kuee.kyoto-u.ac.jp/staff/onat.html |
|             My 6 leg walker, RC airplanes & more in home page |

'Cannot read Microchip PDF files!'
1996\05\28@062335 by fastfwd

face
flavicon
face
Onat Ahmet <RemoveMEPICLISTspam.....MITVMA.MIT.EDU> wrote:

> OK, download the datasheets from Microchip www site. Unfortunatley,
> when I do so, my acrobat reader (for Windoze) says they have been
> damaged, are being fixed, and then says that they are password
> protected...

Onat:

This is usually an indication that you've downloaded the file in
7-bit (ASCII) mode, rather than 8-bit (Binary) mode.

-Andy

Andrew Warren - spamfastfwd@spam@spamix.netcom.com
Fast Forward Engineering, Vista, California
http://www.geocities.com/SiliconValley/2499

'Division by 5 (10) - another cat comes lurking'
1996\05\30@121738 by Martin Nilsson

picon face
> Everyone knows a cat has 9 lives. We have used three on this problem, so there
> are probably six more solutions lurking out there.
>
>
> Scott

Ok, here is another way of doing it:

1. Given x, we first find r = x mod 5 by repeatedly adding the nibbles
of x, and taking this sum mod 5, for instance with a 16-entry table.

2. Then we compute (x - r) * 13107 mod 2^16 (13107 = 3333 hex, ever
seen this one before? :-) = 65535 q mod 2^16 = -q mod 2^16. q is the answer
(exactly).

-- Martin

Martin Nilsson                           http://www.sics.se/~mn/
Swedish Institute of Computer Science    E-mail: mnTakeThisOuTspamsics.se
Box 1263, S-164 28 Kista                 Fax: +46-8-751-7230
Sweden                                   Tel: +46-8-752-1574

1996\05\30@133422 by Scott Dattalo

face
flavicon
face
Martin Nilsson wrote:
>
>
> Ok, here is another way of doing it:
>
> 1. Given x, we first find r = x mod 5 by repeatedly adding the nibbles
> of x, and taking this sum mod 5, for instance with a 16-entry table.
>
> 2. Then we compute (x - r) * 13107 mod 2^16 (13107 = 3333 hex, ever
> seen this one before? :-) = 65535 q mod 2^16 = -q mod 2^16. q is the answer
>  (exactly).
>
>  -- Martin

A couple of comments:

1) r = x mod 5 ==>   0 <= r < 5

2) I think you want to add instead of subtract:

  ((x + r) * 13107 ) mod 2^16

Because if you subtract, your rounding down and your answer will always be 1
less
than the correct answer unless x mod 5 = 0.

As far as the 0x3333 thing, I think that was mentioned (at least indirectly) in
the
first posting. The original objective is to divide by 10. However division by
some
constant, N, can be convert to multiplication by 1/N:

 X           1     2^m
---  =  x * --- *  ---
 N           N     2^m

        x    2^m
     = --- * ---
       2^m    N

For 16 bit integers, m = 16. And 2^16/10 = 0x3333. Thus,

 x
--- = 0x3333 * x >> 16
 10


Since this is the same cat, Martin, we're now down to 5 lives. But, I've got yet
another to skin this guy. One of Andy's steps in solving these arcane problems
involves
looking up Knuth (the messiah of numbers). While riding home last night, I
somehow recalled
a formula that I once saw in "The Art of Computer Programming: Seminumerical
Algorithms",
Vol II. Consider the power series expansion of:

  x        x    /     / e \   / e \2  / e \3      \
-------  = --- * | 1 - |---| + |---| - |---| + ... |
v + e      v    \     \ v /   \ v /   \ v /       /


In our case, we are dividing by 10. So our first shot for v and e might be:

let  v = 8, e = 2

In which case we get:

 x      x
--- =  --- * ( 1 - 1/4 + 1/16 - 1/64 + ... )
 10     8

After some (O.K. a lot of) simplification and rearranging, you end up again with
Andy's
formula.

5 down, 4 to go.

Another combination of v and e is:

 x     3 * x     3 * x     3       x
--- = ------- = ------- = --- * -------
 10    3 * 10    32 - 2    2     16 - 1

Or, v = 16 and e = -1. Substitute this into the power series expansion:

 x     3     x
--- = --- * --- * ( 1 + 1/16 + 1/256 + 1/4096 + ... )
 10    2     16

Which after some simplification gives the answer I had originally posted. Other
combinations of v = 2^i and e = 2^j (i and j are integers) reduce to either one
of these expansions. I suppose you could choose v = 7 and e = 3, however except
on base 7 computers this computation is more difficult.

Thus, we have skinned this poor cat 6 times.

Three more to go. Any more Ideas.


Scott

1996\05\31@104530 by Martin Nilsson

picon face
> From:    Scott Dattalo <.....sdattalospamTakeThisOuTUNIX.SRI.COM>
<snip>
> A couple of comments:
>
> 1) r = x mod 5 ==>   0 <= r < 5
>
> 2) I think you want to add instead of subtract:
>
>    ((x + r) * 13107 ) mod 2^16

No, it should be subtracted.  Sorry if I was unclear. My unstated
assumption was x = 5 * q + r, where 0 <= r < 5. We want q. Then r = (x
mod 5) and ((x - r) * 13107) mod 2^16 = (((5 * q + r) - r) * 13107)
mod 2^16 = ((5 * q) * 13107) mod 2^16 = (65535 * q) mod 2^16 =
((2^16-1) * q) mod 2^16 = -q mod 2^16.

The point is no infinite series or rounding is involved.

> For 16 bit integers, m = 16. And 2^16/10 = 0x3333. Thus,
>
>   x
>  --- = 0x3333 * x >> 16
>   10

I'm afraid, not quite. 2^16/10 = 6553 + 3/5 <> 13107 = 0x3333. But you
are right insofar as -13107 is a multiplicative inverse of 5 modulo
2^16 (it is the modulo part that is important).

> Since this is the same cat, Martin, we're now down to 5 lives. But, I've got
yet

Strictly speaking, there *can't* be such a thing as a different cat,
since division by 10 is a well-defined operation. Any methods that
divides by ten are mathematically equivalent. Or how should we define
"different"...? :-)

-- Modulo Man
(a.k.a. Martin)

Martin Nilsson                           http://www.sics.se/~mn/
Swedish Institute of Computer Science    E-mail: EraseMEmnspamKILLspamsics.se
Box 1263, S-164 28 Kista                 Fax: +46-8-751-7230
Sweden                                   Tel: +46-8-752-1574


'Enough, Dammit! (was: "Re: PicList Survey Results!'
1996\06\01@025121 by fastfwd
face
flavicon
face
Doug:

How many badly-formatted copies of your survey results are you going
to send to the list?

Stop, already.

-Andy

Andrew Warren - fastfwdEraseMEspamix.netcom.com
Fast Forward Engineering, Vista, California
http://www.geocities.com/SiliconValley/2499

'Supersimple non-destructive testing of OTP PICs (a'
1996\06\06@101550 by Martin Nilsson

picon face
I was thinking about PIC testing, and came across the following
nice trick. When you know it, it is obvious, but I haven't seen it
elsewhere, and I think it deserves attention. The trick works on
all 16C6x-8x, OTPs as well as reprogrammables.

This trick is useful in several ways:
- As a simple test program that you put into your stock of "fresh" PICs.
 When you need one you can quickly probe it to see if it has been used,
 without having to read it in a programmer.
- The trick works
 for (partial) testing of OTP devices. It doesn't require changing
 the configuration fuses, and only destroys one word, which could be
 located anywhere in memory. The test discovers if execution logic
 works and may discover if part of the program memory is damaged.
 It executes all program memory locations.
- As a test for an in-system programming circuit.

* Ok, the trick is simple:

  TRIS PORTB

anywhere in memory! Leave the rest at factory default settings.
* GOOD DEVICE: RB7 will switch between HiZ and LowZ with a frequency of
about F[in Hz] = f[in MHz]/m[in k word], where f is the RC oscillator
frequency, and m is the program memory size.
* NG DEVICE: RB7 switches much faster (at least twice F) or much slower.

In other words, the maximally simple blinker program!

Explanation:

The test is the shortest possible PIC program the execution of which
is externally detectable. PIC program memory defaults to all ones,
which on the 6x-8x means ADDLW 0xFF, equivalent to W:=W-1.

There is only one zero-instruction program (all ADDLW 0xFF), but the
execution of this program cannot be observed. The chip could be broken
but you wouldn't know. You can only see the oscillator oscillates.

There are two one-instruction programs that are observable:
1. SLEEP
2. TRIS PORTx

All of these will work, but TRIS PORTB is probably preferrable. The
factory setting for the PIC is Watchdog timer on, with 1:128 prescaler.
SLEEP means the PIC will run through the memory (ADDLW 0xFF), and then
SLEEP for about 2.5 s. This will be detectable by a short blip
on the CLKOUT pin. (The factory setting of the oscillator is RC.)

TRIS PORTA and PORTB will work the same way, but PORTB is more useful.
On startup, PORTB will contain a random value. W will also contain a
random value. On every cycle through memory, W will be incremented by
one (decremented by one n*2^8+255 times), and so will count from 0 to
255 and wrap around. Once every cycle, the TRIS instruction makes the
PORTB pins corresponding to ones in W high impedance, and the others
low impedance. This switching can be visually observed by connecting a
LED and a resistor to the pin.  Pin RBn will display a frequency
F=f/4/m/2^(n+1), where f is the clock frequency, and m is the memory
size. Eg, for a 16C84 with an RC oscillator 3.3 k/20pF, RB7 will
display approx F = 5 M/4/1k/256 = 5 Hz, which is easily visible.  A
broken, non-ADDLW0xFF instruction which doesn't increment W will
typically cause at least a doubling of F. The WDT is enabled, so there
will be "hiccups" every 2.5 s.

Personally, I like the TRIS PORTB version best, but the idea can be
varied. For instance, TRIS PORTB + SLEEP, will make an ultra-slow
blinker program, with period 5s on RB1, 10s on RB2,... about
5 min on RB6, 10 min on RB 7. (Egg timer?)

-- Martin

Martin Nilsson                           http://www.sics.se/~mn/
Swedish Institute of Computer Science    E-mail: EraseMEmnspamspamBeGonesics.se
Box 1263, S-164 28 Kista                 Fax: +46-8-751-7230
Sweden                                   Tel: +46-8-752-1574

'Another comment on sending commands'
1996\06\06@103634 by T.Nelson

flavicon
picon face
Carl Kimball <TakeThisOuTPICLISTspamTakeThisOuTMITVMA.MIT.EDU> wrote:

> The document that was sent to me when I subscribed here is very
> wordy, but very unspecific about sending commands to the list
> server.
>
> It simply says "send a command..." and doesn't say whether the
> command should be on the Subject line, or in the body of the
> message. I guess if you do both, it will figure it out?!?!

As some else previously pointed out - only the body is read.  However,
one should strip out the signature (like mine below) before sending
commands.  Depending on your signature - you may get unwanted results.


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