>
> (first email)
> hy
> i have a question
> what is the difference between a PIC16f84 and PIC16c84
> thanx
>
>                                                Kajcsa Laszlo
>
> --
> http://www.piclist.com#nomail Going offline? Don't AutoReply us!
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>
> Kajcsa
>
> The "C" letter is reference to EPROM, OTP  and  ROM device
>
> The "F" letter is reference to FLASH device.
>
> You can Check the Microchip site: http://www.microchip.com. for further
> information.
>
> Francisco
>
> Kajcsa Laszlo AII III wrote:
> >
> > (first email)
> > hy
> > i have a question
> > what is the difference between a PIC16f84 and PIC16c84
> > thanx
> >
> >                                                Kajcsa Laszlo

>
> (first email)
> hy
> i have a question
> what is the difference between a PIC16f84 and PIC16c84
> thanx
>
>                                                Kajcsa Laszlo
>
> --
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> use EraseMElistservspam_OUTTakeThisOuTmitvma.mit.edu?body=SET%20PICList%20DIGEST

>(first email)
>hy
>i have a question
>what is the difference between a PIC16f84 and PIC16c84
>thanx
>
>
>
>
>
>
>
>                                               Kajcsa Laszlo
>
>--
>http://www.piclist.com#nomail Going offline? Don't AutoReply us!
>use spamBeGonelistservspamBeGonemitvma.mit.edu?body=SET%20PICList%20DIGEST
>
>

>        /--------------------------------------------------------------\
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>
>
>

> Hello List,
>
> This is my first post to this list, and I am just taking up
> micros as a hobby.  In my first project, I am considering using
> a Dallas Semi Digital Potentiometer.  Specifically I am looking
> at the 10K ohm, volatile models.  Has anyone used this glue chips
> in a system with a microchip processor?  A web example would be
> the tops.  Thanks in advance.
>
> Paul Timmerman
>
> --
> http://www.piclist.com#nomail Going offline? Don't AutoReply us!
> use listservEraseMEmitvma.mit.edu?body=SET%20PICList%20DIGEST
>
>
>
>
>

> hi!
> i have a problem
> i made this program but it has a "bug"
> when i simulate it with mplab it works still he arrive to sleep command
> then with asynchronous stimulus i change the RB7 pin state
> after that he jumps back to the movlw 0x88 instruction and INTCON reg.
> became 0x09
> what is wrong
> thanks
>
> here is a part of the code
>
> ;program for a beam-robot spider
> ;wait's for change on portb.7 pin then turns left or right
> ;1.1
>           list p=16f84     ;microcontroller type
> #include "p16f84.inc"      ;use this symbols
>           org 0            ;start here
> CTR equ 0x0e               ;define control register CTR
>           bsf STATUS,5     ;bank1
>           movlw 0x00       ;ra4:ra0 +
>           movwf TRISA      ;outputs
>           bcf OPTION_REG,7 ;set OPTION_REG(enable pull-up rezistors)
>           movlw 0x88       ;set INTCON register +
>           movwf INTCON     ;(enable interrupts and the rb7:rb4 interrupts)
>           bcf STATUS,5     ;bank0
>           bcf CTR,0        ;clear control bit
> forward:  movlw 0x09       ;first +
>           movwf PORTA      ;porta value
> forward2: sleep            ;sleep and wait for change(to became high) on
> portb.
> wait:     bcf INTCON,0     ;after sleep clear the RBIF bit
> nr0:      movlw 0x02       ;start aprox. .5s delay
>           movwf 0x0d       ;for clock=4 MHz
> .
>
> .
>
> .
>
>
>
>
>
>
>                                                Kajcsa Laszlo
>
> --
> http://www.piclist.com#nomail Going offline? Don't AutoReply us!
> email spamBeGonelistservEraseMEmitvma.mit.edu with SET PICList DIGEST in the body
>
>

> ;program for a beam-robot spider
> ;wait's for change on portb.7 pin then turns left or right
> ;1.1
>           list p=16f84     ;microcontroller type
> #include "p16f84.inc"      ;use this symbols
>           org 0            ;start here
> CTR equ 0x0e               ;define control register CTR
>           bsf STATUS,5     ;bank1
>           movlw 0x00       ;ra4:ra0 +
>           movwf TRISA      ;outputs
>           bcf OPTION_REG,7 ;set OPTION_REG(enable pull-up rezistors)
>           movlw 0x88       ;set INTCON register +
>           movwf INTCON     ;(enable interrupts and the rb7:rb4 interrupts)
>           bcf STATUS,5     ;bank0
>           bcf CTR,0        ;clear control bit
> forward:  movlw 0x09       ;first +
>           movwf PORTA      ;porta value
> forward2: sleep            ;sleep and wait for change(to became high) on
> portb.
> wait:     bcf INTCON,0     ;after sleep clear the RBIF bit
> nr0:      movlw 0x02       ;start aprox. .5s delay
>           movwf 0x0d       ;for clock=4 MHz

> I am working on the PIC16F877. I would like someone
> to
> provide me with sites or related codes to drive a DC
> motor with a PID algorithm with the above IC.
>   The i/p is 0-5v error signal which is compared
> with
> a ref and o/p signal computed using PID algorithm
>
> __________________________________________________
> Do You Yahoo!?
> Yahoo! Shopping - Thousands of Stores. Millions of
> Products.
> http://shopping.yahoo.com/
>
> --
> http://www.piclist.com hint: PICList Posts must
> start with ONE topic:
> [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other
> [BUY]:,[AD]: ->Ads
>
>

> > > I am working on the PIC16F877. I would like
> > someone to provide me with sites or related codes
> to
> drive a DC motor with a PID algorithm with the above
> IC.
>  The i/p is 0-5v error signal which is compared with
> a ref and o/p signal computed using PID algorithm
>    A small module of the above problem will be
> sufficient, I just want to get a hold on the syntax
> involved in assembly language programming.
>
>
>
> __________________________________________________
> Do You Yahoo!?
> Yahoo! Shopping - Thousands of Stores. Millions of
> Products.
> http://shopping.yahoo.com/
>
> --
> http://www.piclist.com hint: The PICList is archived
> three different
> ways.  See http://www.piclist.com/#archives for
> details.
>
>

> Hi,
>
> I lost all my notes that I saved from this list.  I hope someone can give me
> the
> URL for the company in Bulgaria that makes prototype PC boards
> for PICs.
>
> Thanks,  Royce
>
> --
> http://www.piclist.com hint: To leave the PICList
> spamBeGonepiclist-unsubscribe-requestKILLspam@spam@mitvma.mit.edu
>

> > the
> > URL for the company in Bulgaria that makes prototype PC boards
> > for PICs.
> >
> > Thanks,  Royce
> >
> > --
> > http://www.piclist.com hint: To leave the PICList
> > spamBeGonepiclist-unsubscribe-requestspam_OUTRemoveMEmitvma.mit.edu> > >
>
> --
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> .....piclist-unsubscribe-requestRemoveMEmitvma.mit.edu
>
>

> -----Original Message-----
> From: pic microcontroller discussion list
> [RemoveMEPICLISTspam_OUTMITVMA.MIT.EDU]On Behalf Of techhead
> Sent: Friday, November 08, 2002 7:07 PM
> To: PICLISTspamMITVMA.MIT.EDU
> Subject: DS1202
>
>
> I have a DS1202 clock that is sort of running. It doesn't count
> correctly. It starts at 0 seconds then counts up to 9 then jumps to 15

> counts for a bit then jumps again and counts then jumps and it counts
> all the way to 99 seconds then rolls over. I have included my code
> below. Any help would be appreciated.
>
> Include "MODEDEFS.BAS"  ' Include Shiftin/out modes
>
> DEFINE OSC 4
> 'Define  LCD_DREG        PORTD   ' Define LCD connections
> 'Define  LCD_DBIT        4
> 'Define  LCD_RSREG       PORTE
> 'Define  LCD_RSBIT       0
> 'Define  LCD_EREG        PORTE
> 'Define  LCD_EBIT        1
>
> ' Alias pins
> RST     var     PORTB.4
> IO      var     PORTB.1
> SCLK    var     PORTB.3
> Lout    var     PORTB.2
>
> ' Allocate variables
> rtcyear var     byte
> rtcday  var     byte
> rtcmonth var    byte
> rtcdate var     byte
> rtchr   var     byte
> rtcmin  var     byte
> rtcsec  var     byte
> rtccontrol var  byte
>
>
>         Low RST         ' Reset RTC
>         Low SCLK
>
>         OPTION_REG.7 = 0        ' Enable PORTB pullups
>
>         Pause 10       ' Wait for LCD to startup
>
>         ' Set initial time to 8:00:00AM 06/06/02
>         rtcyear = $02
>         rtcday = $06
>         rtcmonth = $06
>         rtcdate = $06
>         rtchr = $08
>         rtcmin = 0
>         rtcsec = 0
>         Gosub settime   ' Set the time
>
>         Goto mainloop   ' Skip subroutines
>
>
> ' Subroutine to write time to RTC
> settime:
>         RST = 1         ' Ready for transfer
>
>         ' Enable write
>         Shiftout IO, SCLK, LSBFIRST, [$8e, 0]
>
>         RST = 0         ' Reset RTC
>
>         RST = 1         ' Ready for transfer
>
>         ' Write all 8 RTC registers in burst mode
>         Shiftout IO, SCLK, LSBFIRST, [$be, rtcsec, rtcmin, rtchr,
> rtcdate, rtcmonth, rtcday, rtcyear, 0]
>
>         RST = 0         ' Reset RTC
>         Return
>
> ' Subroutine to read time from RTC
> gettime:
>         RST = 1         ' Ready for transfer
>
>         Shiftout IO, SCLK, LSBFIRST, [$bf]      ' Read all 8 RTC
> registers in burst mode
>         Shiftin IO, SCLK, LSBPRE, [rtcsec, rtcmin, rtchr, rtcdate,
> rtcmonth, rtcday, rtcyear, rtccontrol]
>
>         RST = 0         ' Reset RTC
>         Return
>
> ' Main program loop - in this case, it only updates the LCD with the
> time
> mainloop:
>         Gosub gettime   ' Read the time from the RTC
>
>         ' Display time on LCD
>         Serout lout,N9600,[254,1]    ' Clear Display
>         'Serout lout,N9600,[254,128,"hello"]
>         Serout

> We are a small company. We do not manufacture 10K
> units just because we can
> and because it's not "saleable" on our market.
> Just as a lateral comment: It also makes VERY hard
> to manufacture a product
> with a custom and "nice" enclosure, since a smelting
> matrix is, on most
> cases, not affordable.
>
> How ever, we need to provide our customer with what
> they need, because:
>        - They will go out and pay the difference to get an
> imported version
> of our product
>        - So we can export if we see the possibility
>
> Perhaps its hard to understand, Olin, I can see it.
> But we are actually
> working on a market here that require a high end
> product, but in small qtys
> and at a low price. That's actually the problem.
>
> Regards,
> Mauricio (Argentina)
>

> Check this site out for an ICD2 clone
>
> http://stolz.de.be/
>
>
> I built it and it works great as a programmer and
> works with the
> MICROCHIP MPLAB interface.
>
> I have not been able to make it work in debug mode
> but this is most
> likely the way I have bread boarded the project.
>
> Also check out http://www.olimex.com/dev/
>
> Look under emulators/debuggers
>
> The ICD2 may no cover every chip but its main
> advantage to me is it
> directly interfaces with the MICROCHIP MPLAB and
> this will show you what
> chips can be programmed when you look under
> CONFIGURE/SELECT DEVICE...
>
> Also it has the advantage of having new chips added
> as Microchip updates
> it's MPLAB program.
>
> _______________________________________
> Roy
> Tauranga
> New Zealand
> _______________________________________
>
>  
>
> --
> No virus found in this outgoing message.
> Checked by AVG Anti-Virus.
> Version: 7.0.308 / Virus Database: 266.11.0 -
> Release Date: 29/04/2005
>  
>

> -----Original Message-----
> From: piclist-bouncesspamBeGonespamBeGonemit.edu
> [spamBeGonepiclist-bouncesmit.edu] On Behalf Of spam_OUTPban1STOPspamaol.com
> Sent: 2005 Jun 27, Mon 13:48
> To: RemoveMEpiclistspammit.edu
> Subject: [PIC]
>
>  
> I am new to Pic programming, I want to write my first code  
> using MPLAB, but I do not know where to start. Can you please
> tell me all  the steps to follow.
>  
> Thanks
>

>> I'd seriously recommend AGAINST the PIC16F84A. I started my PIC
>> adventure in May, and because of Myke Predko's book I started with the
>> PIC16F84A, but it became clear that was a bad choice in many different
>> ways.
>
> Ah, a fresh starter. An agrument that is often stated *against* almost
> any PIC except the 84's is that there are some any peripherals that a
> newbie will be confused. Having been there just a short time ago, could
> you comment on this? (no need to convince *me*, but your experience
> might be usefull to convince other newbies to make the right choice).

> Again, we should separate learning microcontrollers from learning PICs.
> Maybe learning microcontrollers should be done with a 10F204.  It's very
> simple, has no banking and paging issues, and is about as low level as it
> gets.  All the concepts of direct interaction between the firmware and
> hardware can be learned there.  Once that is out of the way, someone
> should
> have the background to make sense of any PIC or other microcontroller.
> The
> 10F204 has the advantage that it clearly doesn't have the capabilities for
> most projects, so there isn't the issue of clinging to it to stay with
> something familiar.

> Maarten Hofman wrote:
>> I'd seriously recommend AGAINST the PIC16F84A.
>
> I agree.  The wide variety of PICs is so that there is a reasonably
> tight fit to many possible applications.  Most PICs get sold in to high
> volume applications where a few cents makes a difference.  For a
> hobbyist an extra few $$ for a "full function" PIC per one-off project
> is irrelevant.  There are only a few PICs that make sense for hobby
> purposes.
>
> If you want to stick to the 16F family for access to existing code, the
> 16F876A is the best general purpose choice.  It comes in an easy to
> handle 28 pin DIP.  If you plan on doing your own thing and don't care
> about example code on the web, I definitely recommend the 30F3013.  It
> is in the new dsPIC line and also comes in a 28 pin DIP package.  The
> dsPICs are definitely the most capable PICs.  It takes a little more to
> learn the processor and instruction set up front, but once you get
> there they are more friendly to program.
>
> There are several other good hobbyist chips, but I only recommend them
> given specific requirements of a project.  For example, there are 40
> pin and quite capable 18 and 8 pin parts that can be reasonable choices
> for hobby projects depending on the circumstances.  But if you're
> asking for the best general purpose hobby PIC without specific
> requirements, my first answer is the 30F3013.
>
>
> *****************************************************************
> Embed Inc, embedded system specialists in Littleton Massachusetts
> (978) 742-9014, http://www.embedinc.com

> Byron A Jeff wrote:
>> I'm in the process of developing a computer systems lab using PICs. I
>> haven't settled on a chip yet, but it will be one with top end
>> capability for the reasons that you have outlined.
>
> What are you going to use for a hardware platform to put the PIC on?
> I'm developing a series of PIC prototyping boards that I think would be
> great PIC learning platforms.  The first production batch is in process
> now.  If things work out as I expect, then I'll probably be selling
> singles for around $40 and 5 at a time for $35 each.  I'd be interested
> in working out a "whole class" educational volume discount, probably
> somewhere in the $20s.
>
> I don't know what textbooks cost nowadays, but they were in the $10 to
> $20 range in the late 1970s, so I can only imagine that under $30 is
> less than most textbooks today.
>
> The first PIC prototyping board is aimed at the "standard" 28 pin DIP
> pinout, like the 16F877A or 18F2520.  From your description, it sounds
> like you are probably aiming at one of these chips anyway.
>
> The board comes with wall wart, built in power supply, diagnostic LEDs
> for 8 signals with separate LEDs for high and low level, RS-232
> interface, and a large prototyping area with vertical strips of 5 pads
> and horizontal power/ground busses and a ground plane.  There are
> jumpers to all the built in extras, so the PIC can be disconnected and
> treated like a bare chip as desired.  There are also pads for optional
> features that don't come pre-populated, like a spike clamp for use with
> automotive 12V power, two types of crystal/resonator footprints, and
> timer 1 oscillator.
>
> Please let me know if you'd like to persue this.  I think that thru my
> volume I can make things available to your students that would be
> difficult or expensive for them (or you) to do individually.  I know
> you are quite capable of designing and building something like this
> yourself, but I've already done it and can probably produce it cheaper.
>  I think you would also rather spend your time developing educational
> content than dealing with all the hassles of getting a batch of
> anything produced in volume.
>
>
> *****************************************************************
> Embed Inc, embedded system specialists in Littleton Massachusetts
> (978) 742-9014, http://www.embedinc.com

>
> > > I started my PIC
> > > adventure in May, and because of Myke Predko's book I started with the
> > > PIC16F84A, but it became clear that was a bad choice in many different
> > > ways.
> >
> > Care to list?
>
> In order of importance:

> 1) The PIC16F84A doesn't have an internal oscillator. This makes the
> electronics and especially the prototype more complicated, and eats
> two of your precious pins. Worse: if you later decide to upgrade your
> circuit with the PIC16F628A, you STILL can't use those pins, because
> the resonator is connected to them.

> 2) I'm pretty sure some people would like their PIC to speak to their
> PC in some way, if just to send a few words of configuration to it.
> Granted, you can connect a RS-232 to a PIC16F84A with a mere 10KOhm
> resistor (though I recommend adding those two diodes as well, just in
> case). However, what you save in hardware, you suffer in software...
> Waiting for start bits, timing the distance right, and certainly
> reducing the speed of your application. With the PIC16F628A you need
> three instructions (as well as a little setup, and an additional
> transistor and resistor, to invert the incoming signal) and all works
> as it should. Note that the entire code to get the PIC16F628A to work
> with RS-232 is listed in its datasheet, so it's not like you have to
> figure things out yourself.

> John J. McDonough wrote:
>> Like ... 16 bit registers,
>
> Right, it's a 16 bit machine.
>
>> except for the 40 bit ones (why 40?)
>
> You failed to mention that these are the two DSP accumulators.  They are
> meant to perform 16 bit multiply-accumulate operations, so it makes sense
> for the them to be 32 bits wide.  The extra 8 bits are for overlow, which
> is
> a very nice touch.  Some DSPs have don't have such a wide accumulator, and
> it gets to be a pain.
>
> However unless you are doing DSP operations, just ignore the DSP
> accumulators and the DSP instructions.  They are different because of what
> they need to do, but you don't have to use them.
>
>> Some memory accessible to some instructions some of the time
>
> Think of it this way.  RAM is addresses indirectly thru another register,
> but some instructions give you a way to address the first K or so (I don't
> remember right now) directly as a bonus.
>
>> Two different ALUs with pretty different behavior ... probably a good
>> thing, but odd
>
> Not at all for a DSP.  Again, if you're not doing DSP, just ignore that
> part.
>
>> Almost all instructions 1 cycle except for a few 18 cycle ones ...
>
> You neglected to mention these are divide instructions.  It would be a
> true
> miracle if they could put a 32 by 16 bit divider for that price and power
> in
> there that took only one cycle.  As it is, you get a 16 x 16 into 32 bit
> multiply in one cycle.  The other PICs don't have dividers at all.  What
> would you rather have, no divide instruction or one that takes 18 cycles?
>
>> and the few that take two cycles unless you hold your head just right
>> in which case they take 3.
>
> Of coures branches take 2 cycles, just like on other PICs.
>
>> And no, not simple and predictable like btfsc.
>> GP registers useable as GP registers some of the time
>>
>> Hardly orthogonal!
>
> Mostly orthogonal except where the feature dictated otherwise.  Overall I
> think the dsPIC is a really nice well designed microcontroller that does a
> real good job at what it is intended for.
>
>> And yeah, I make it sound worse than it is.
>
> Yes, you are being rather unfair.  Everything is a tradeoff.  Keep in mind
> these things go into cost sensitive applications.  The important part is
> how
> much capability and performance can be squeezed out of silicon that has to
> sell for $5 packaged.  Whether the instruction set is 100% orthogonal or
> every instruction takes the same number of cycles is not that important in
> the scheme of things.
>
> Personally I find the dsPIC easy to program, even compared to other PICs.
>
>
> *****************************************************************
> Embed Inc, embedded system specialists in Littleton Massachusetts
> (978) 742-9014, http://www.embedinc.com

> John J. McDonough wrote :
>
> > From: "Martin K" <martin-distlists@nnytech.
> net>
> > Subject: Re: [PIC]
> >
> >
> > > I looked it up in the family
> reference and it says a freq.
> > > of 7.5MHz with
> > > a 16x PLL
> results in 120MHz =)
> >
> > Yes, well, that's another "quirky" thing.  
> The processor
> > clock may or may not be the same as the crystal
> >
> frequency.
>
> "Quirky" compared with what ?
>
> Or, in other words, how is
> that different
> from the PIC18-series ?

> Daniel Chia wrote:
> > Unfortunately at this time there really isn't that many dsPIC tutorials
> > for beginners. But for most MCU-like purposes the dsPIC is pretty much
> > like the 18f although working with the byte manipulation instructions do
> > have their quirks.
>
> I have to disagree with this.  The dsPIC isn't really that close to other
> PICs as far as programming goes.  The multiple W registers, register
> indirect addressing, and dedicated stack point give it a different feel from
> the 18F.
>
>
> *****************************************************************
> Embed Inc, embedded system specialists in Littleton Massachusetts
> (978) 742-9014, http://www.embedinc.com

> -----Original Message-----
> From: spampiclist-bounces..........mit.edu [piclist-bounces.....mit.edu] On Behalf Of
> KILLspami2cspam_OUTbtinternet.com
> Sent: 16 February 2006 17:38
> To: spam_OUTpiclistTakeThisOuTmit.edu
> Subject: [PIC]
>
> This is a compiler question,
>
> In p18f4550.f we find all the hardware registers declared
> (extern), but where are the definitions?

>From: "Maarten Hofman" <spam_OUTcashimorTakeThisOuTEraseMEgmail.com>
>Reply-To: "Microcontroller discussion list - Public." <EraseMEpiclistspamBeGoneKILLspammit.edu>
>To: "Microcontroller discussion list - Public." <RemoveMEpiclistspamBeGonespammit.edu>
>Subject: Re: [PIC]
>Date: Thu, 9 Mar 2006 22:52:05 -0500
>
> > I am an experienced programmer in C and Basic on PCs and am looking to
> > program 16F84, 16F628, 16F876 and 16F877 chips.
>
>I recommend NOT using the 16F84, using a 16F648A instead of the 16F628
>(unless you plan to do a commercial product, but in that case you can
>always scale down to the 16F627A/16F628A afterwards), and using the
>16F876A and 16F877A instead of the 16F876 and 16F877. See discussions
>elsewhere on this list for more information. I would also seriously
>consider looking into the 18F series of PICmicros. They tend to be
>more C friendly (resulting in even tighter code), are not much more
>expensive and have many features that now make me wish I had used them
>from the start. Of course, all this depends on having a good
>programmer, but as the PICkit 2 is inexpensive and now supports most
>PICmicros, there isn't a really good excuse to sticking with old PICs
>because of a bad programmer.
>
>Greetings,
>Maarten Hofman.
>

> > void delay (void)
> > {
> >   for (i = 0; i < 10000; i++)
> >     ;
> > }
> >
> Depending on compiler specifics, this might be a very short
> delay to pair to human perceptions.  I have a "flame" simulator
> that changes the brightness of some LEDs with a 128 count inner
> PWM loop and a 50 count outer loop (so, approximately equivilent
> to a 6400 count single loop) that flickers at a reasonably
> realistic rate (several times per second, at least), and it has
> a lot more stuff in the inner loop than your code.  I seem to
> recall that PICs at nominal frequency take 24 bits worth of
> count to get delays in the one-second range.  (Hmm.  That was
> implicit in your timer-based attempt.  prescale of 32 on a a
> 16 bit counter is ~2million cycles per second.)  I would hope
> your compiler does the delay loop in far less than 100 cycles,
> for a delay period of far less than 0.5 seconds...

>
>
>> Maybe first just try to turn led on or off.  See what led does when you
>> don't turn it on or off, then try to get  it to change state.  Once you
> get
>> it where one program turns it on and another program turns it off, you
>> can
>> try to get it to flash.
>
> ok, I will try this now, i.e. turn a led on, then off, then on, then
> check if it is still on after that. I shall report back shortly.