[first, re the OT discussion: how about "[OT]", to avoid confusing with
some 'real' subject with OT in it?]
At 10:52 PM 28-08-97 +0000, Mike Smith wrote:
>> I didn't think copying software was criminally illegal. ie: You can
>> be sued for copying it, but not charged with a criminal offense such
>> as theft. If I'm right (which is open to debate) then comparing it
>> to the theft of a car isn't appropriate.
>
>Morally equivalent. Whether its a criminal or legal case would
>depend on the jurisdiction.
where do you take your 'moral equivalence' from? do you want to say that
the law is imoral (making a difference where 'morally' there is none)? is
it then 'moral' to obey to an 'imoral' law? one has to be careful on these
slippery slopes of 'moral'... (BTW, 'morals' has been one of the most
(ab)used excuses for almost _any_thing.)
>> It's more like borrowing a friends cassette tape and making a copy
>> for yourself. Or recording a song off the radio. I'm curious how
>> many people who are so gung-ho against copying software, have copied
>> audio.
>
>That depends on intent. Cases you describe are illegal. Copying a
>CD you own, for playing in your car cassette, is something I'd be
>comfortable with. After all, I'm only using it in one place at any
>one time. Akin to network software licensing, where you can run a
>program on a given number of workstations simultaneously.
are you _sure_ that nobody at home is listening to your CD while you're
listening to your copied tape? (you've got no 'network' license for your
music...)
>> Or went to the library and photocopied a specs sheet, or had one
>> faxed, when it should have been purchased.
>
>Crazy example. Most manufacturers are *happy* for you to have their
>data, and will give you the books, CD's etc. Do you feel guilty
>downloading pdf files?
I just had a look at a Motorola databook, and the only thing I saw was a
copyright notice "All rights reserved". Which, according to my
understanding of copyright, means that it is illegal to copy it unless you
have the permission of the copyright owner. Am I wrong here?
A different issue is that you assume they allow you to do so, and that they
are even happy that you do so, because it spreads the knowledge about their
products. Similarily someone could argue that one of the reasons for the
rise of Microsoft was that their software was probably among the most
copied ever, and so it's reasonable to ssume that every software
manufacturer wants to have the same success, and so all are happy to having
their software copied...
>For some purposes, photocopying copyrighted material is allowed.
yes, but probably not for business use.
>Most libraries have a sign describing 'Fair Dealing'
At 09:56 AM 29/8/97 -0400, you wrote:
>At 07:55 PM 8/29/97 +0000, you wrote:
>>On 29 Aug 97 at 7:11, Pasi Patama wrote:
>>
>>> spam_OUTppatamaTakeThisOuThit.fi
>>>
>>
>><sigh> So the word Unsubscribe goes into the offtopic folder too.
>>(assuming ppl can spell it.)
>
>Wats hte crroect speling?
>
>Andy
>
>
> What you fellows have against New Zealand Sheeps!!
>
> Jagath
>
> Landcare Research
> New Zealand
>
> >>> Eric van Es 29/August/1997 07:53am >>>
> Andrew McDonald wrote:
> >
> > On Thu, 28 Aug 1997 09:19:56 +1000, you wrote:
> >
> > >>>If only there was a way to capture the methane and use it! I could
> drive
> > >>>my car on f*rt!
> > >>>
> > >>>Hiya - there go the Arab oil barons....
> > >>
> > >>Hey - where do you think they got their oil and gas in the first place ?
> > >>
> > >>Rgds, Mike, Perth, Western Australia
> > >>
> > >
> > >Err, maybe from New Zealand sheep .....
> > >
> > Incidently we (NZ) used to have live sheep exports to the middle east.
> > Don't know if we still do... I know there was a fire on one of the
> > ships a while ago.
> >
> What do you call that then - a barbeque? <g> Pity - I can imagine the
> mayhem, pain...
>
> BEFORE ANYONE ACCUSES ME OF CRUELTY - I LOVE MY DOG! ...and
> other
> animals big & small...
>
> --
> Eric van Es | Cape Town, South Africa
Well not much Jagath - except the smell :-) Nagh just pulling your
leg... (After all you work for LANDCARE?!)
I suppose we'd all like to play rugby like you guys.... so for the
meantime we'll just rip off your sheep!
In message <3.0.32.19970829112836.00697eecKILLspampop5.ibm.net> .....PICLISTKILLspam.....MITVMA.MIT.EDU
writes:
> At 12:05 PM 29-08-97 +0000, Mike Smith wrote:
> >No, I wasn't making a case for the morality or otherwise of the law,
> >although a case could be made that the law as it is today is immoral,
> >with the side with the most expensive legal team having a better
> >chance of winning, rather than the case being determined purely on
> >judicial terms.
>
> again the (unanswered) question: if 'moral' and 'legal' by your definition
> are obviously not the same, where do you take your definition for 'moral'
> from? ('legal' is more or less defined -- at least that's what the courts
> try to do :-)
>
'Moral' and 'legal' are different. There are things that it is legal
to do which are immoral (in my opinion).
For example, adultery, legal, but in my opinion immoral.
There are many sources of what is considered to be moral - peer groups
define a group morality, tv and radio affect the perceived morality
of a society, books, newspapers, all have an influence on this.
Parental input helps to define a childs moral outlook as do their
teachers - which is why I am careful to choose a school for my
children which has the same (or at least similar) philosophy of
life to my own.
As for a complete definition of morality - The Bible has to be up there
near the top of the list - the only problem is it sets high standards which
are often at variance with modern society, so what is required seems so
un-attainable, which is why mercy and grace were put in there.
> I'm starting to wonder if someone's doing it on purpose. Has
> anyone been checking the extended headers, to see if the messages
> are all comming from the same place?
There does seem to be a general impression that the addresses of the
"unsubscribers" are bogus as messages directly to them bounce.
> I think that you are right that most HTML code on the Internet is
> copyrighted. However, this copyright is intended to prevent re-
> publishing the HTML code, not saving it for your own use.
Is it even intended, or *realistically* expected to do that? Are Web
publishers likely to object to the generation of a (de-facto) mirror
site? Other, that is, than the possibility that such a mirror site will
not represent the latest version? Most publishers on the Web, because
access is free, would expect the prime function of copyright to be to
ensure that what is purported to be their work is indeed so, and that
others' purported work does not contain theirs without due agreement.
They are not (necessarily) demanding payment, but their good name.
Certainly, links if not file copies are universally acceptable. It is
*expected* that browsers (people) are sufficiently competent to "strip
back" link addresses to locate the owner even if "home" vectors are not
contained in every page.
> It probably even would allow you to transfer your saved copy to a
> friend because that action would be the same as that friend just going
> to the URL and getting his own copy.
Perfectly reasonable, albeit impossible to police anyway. It
certainly is a funny beastie, this Internet.
>As processors get faster in general, applications DON'T get faster
YES for sure if Billy is involved - see the Windows threads.
software must get more complex to require new hardware
to give more profit to the desktop computer industry :(
NO in some other cases.
Actually, I made that comment coming mainly from a "small mainframe"
world. The DEC-20's I used to program (10 to 20 years ago) would support
about 50 to 100 users doing email and editting and programming classwork,
using dumb terminals connected via a network or to hardwired terminal
ports, a couple 700MB drives the size of washing machines, and about 20MB
of memory. (4 Mwords, 36 bit words.) I think they ran at about 1 MIP.
Today, the same 100 users, doing approximately the same thing, require
a multi-processor sparcserver of some kind with several hundred mips,
several 12Gbyte disk drives, and 256Meg of memory. Of course, now the
network terminals are X terminals, and so on... "real" SW development
requires a different machine, of course.
[doing it in SW on Atmel AVR]
all those things run in the background and can be considered as virtual
hardware a concept we feel Parallax and Scenix are targetting too.
On the small AVRs, I'd worry about code space consumed as well...
[home DIY system would]
Cold boot in 4 seconds maximum.
Man, it was SO depressing when I upgraded by aging MacIIci (25 MHz
68030) to a new Mac (8500 - 120MHz powerPC with theoretically faster
disks) and it didn't boot any faster :-(
Do you want me to send you a dead sheep....... so... you can beat the
hell out of it??
Regards
Jagath
>>> Eric van Es 30/August/1997 08:04am >>>
Jagath Ekanayake wrote: {Quote hidden}
>
> What you fellows have against New Zealand Sheeps!!
>
> Jagath
>
> Landcare Research
> New Zealand
>
> >>> Eric van Es 29/August/1997 07:53am >>>
> Andrew McDonald wrote:
> >
> > On Thu, 28 Aug 1997 09:19:56 +1000, you wrote:
> >
> > >>>If only there was a way to capture the methane and use it! I could
> drive
> > >>>my car on f*rt!
> > >>>
> > >>>Hiya - there go the Arab oil barons....
> > >>
> > >>Hey - where do you think they got their oil and gas in the first place
?
> > >>
> > >>Rgds, Mike, Perth, Western Australia
> > >>
> > >
> > >Err, maybe from New Zealand sheep .....
> > >
> > Incidently we (NZ) used to have live sheep exports to the middle
> > Don't know if we still do... I know there was a fire on one of the
> > ships a while ago.
> >
> What do you call that then - a barbeque? <g> Pity - I can imagine the
> mayhem, pain...
>
> BEFORE ANYONE ACCUSES ME OF CRUELTY - I LOVE MY DOG! ...and
> other
> animals big & small...
>
> --
> Eric van Es | Cape Town, South Africa
Well not much Jagath - except the smell :-) Nagh just pulling your
leg... (After all you work for LANDCARE?!)
I suppose we'd all like to play rugby like you guys.... so for the
meantime we'll just rip off your sheep!
> > go back to
> > work, would you like to
> > gain more financial freedom? This is the easiest home business
> > you will ever
> > see!!!
> >
> > COMBINING the power of THE INTERNET and NETWORK MARKETING,
> > this opportunity is hitting the mass consumer/opportunity-seeker
> > like no one
> has
> > seen before.
> >
> > You can make $400-$14,000/month in your spare time!!!
> [snip]
>
> Why o why o why can't the piclist be run on some other listserver
> application, so that some filtering can be implemented? Like
>
> 1 Do not allow postings from anyone not subscribed to the list 2
> Filter and process unsubscribe (and unscribe:-)) commands 3 Filter
> out off-topic messages so that users can SET OFFTOPIC OFF 4 Filter
> out messages that score too high on
> - CAPITAL LETTERS
> - Exclamation marks!!!!!!
> - $$$DOLLAR$$SIGNS$$$$
> - Sequences like "easy business", "network marketing",
> "make $*/week", "move all names in the list up", "in your
> spare time" "completely leagle" (sic) etc. etc.
You forgot - "This is not a pyramid scheme" & "To remove your name
from this list" :(
>
> The server could then reply with a helpful message (sO tHAT mIGUEL
> cAN rEPOST hIS mESSAGES). I'm sure that writing a listserver
<snicker>
> application shouldn't take more than a few days, really.
Indeed, a PC mailer app with rules could just about manage it on its
own. Set it so it logs on say, every hour, reads messages, filters,
and reposts them to the ppl on the list. ppl not on the list would
not get thru. Known spam domains such as savetrees could get a
'nothanks' if they tried to join.
The only downside I see is
- slower response times (1 hour updates)
- annoyed ISP of whoever was running the list.
MikeS
<mikesmith_ozspam_OUTrelaymail.net>
Frank A. Vorstenbosch wrote:
>>
>> The server could then reply with a helpful message (sO tHAT mIGUEL
>> cAN rEPOST hIS mESSAGES). I'm sure that writing a listserver application
>> shouldn't take more than a few days, really.
>We can't wait try try your listserver version out.
>BTW I think mIGUEL's CAPS lock key is stuck... :)
I think its time mIGUEL baught a new keyboard as the old one appears to be
past the end of its 'working' life!
>Dear Postmaster
>
>One of your direct or indirect users spammed me.
>
>Please take action against them in accordance with your terms of
>service.
>
>TIA
>
>Mike Smith
>
>
>
>>
>> Go to: http://members.tripod.com/~SLZ/ (please use
>> uppercase
>>for SLZ)
>>
>> or: http://www.cyber-action.com/oed/slz.html
>>
>> The Website above provides all the details for this exciting
>> information. Please visit the above website for details. Thanks!
>>
>>
>> Have a Great Day!
>>
>> Sincerely
>>
>> Larry Johnson
Thank you for your concern and for bringing this to our attention. The
page that was listed in the message is no longer being served by
Tripod.
I wanted to clarify that the creator of that page was in no way
directly associated with Tripod, Inc. Tripod does not exercise any
editorial control over what our members place on their pages, nor
their other Internet related activities such mailings or newsgroup
postings.
Tripod does, to the best of our ability, delete pages that blatantly
violate common "Netiquette" as we are made aware of them.
I apologize for any inconvenience you have experienced. If you have
any further questions or comments please do not hesitate to contact
me.
> On Tue, 2 Sep 1997, myke predko wrote:
>
> > Boy, did you leave yourself open on this one.
> >
> > >Here's the situation:...
> > <Nuked>
> > ...Which usually means you're NOT on a peice of code. But I
> > >clearly am.
Don't worry Shane - when you get right down to it, we are all just
pieces of code (fairly complex ones, too) - from our DNA down to our
snappy little synapses and neurons.
> > "One must invoke enough raw truth to punch a hole in the world" - Darl Af
> >
>
> Punch? How about invoking enough precise knowledge to poke a hole in
> it?:)
Not really the solution.... but you can use the HP7475 printer driver to
generate hpgl/1.
I was looking for hpgl/2 to hpgl/1 translator some while ago for our
legacy Versatec 32" plotter but did'nt find any.
But finally found the solution in a PostScript level 1 to hpgl/1 translator.
>
> Not really the solution.... but you can use the HP7475 printer driver to
> generate hpgl/1.
>
> I was looking for hpgl/2 to hpgl/1 translator some while ago for our
> legacy Versatec 32" plotter but did'nt find any.
> But finally found the solution in a PostScript level 1 to hpgl/1 translator.
>
> Regards,
> Peter Tiang
> RemoveMEtiangcfoonEraseMEEraseMEhitachi.com.my
>
> ==============================================================================
>
> >>> David BALDWIN <RemoveMEdbspam_OUTKILLspamSDM.BEL.ALCATEL.BE> 3/September/1997 03:57pm >>>
> Highly out of topic!
>
> Hi,
>
> I am looking for hpgl/2 to hpgl/1 translator. Anybody heard about it?
>>> David BALDWIN <EraseMEdbspamspamBeGoneSDM.BEL.ALCATEL.BE> 3/September/1997 06:13pm >>>
<snipped>
>>
>> Not really the solution.... but you can use the HP7475 printer driver to
>> generate hpgl/1.
>>
>
> Do you think I can find Win95 driver for it?
Yes, the HP7475 printer driver is a standard driver included in the
Win95 installation CD.
Click on Control Panel->Printers->Add Printers....
< Sean RS Costall writes>
> You modified Myke's PICLIST etiquette rules, fine.
>
> But did you HAVE TO COPY THE ENTIRE @#$%#$&%#%$^& MESSAGE IN YOUR
REPLY?????
>
> Idiot.
>
> -S.
>
> On Wed, 3 Sep 1997, Joost Kooij wrote:
>
> Hi Joost Kooij,
>
> [..}
> > > Does anyone know how efficient normal transformers (230V => e.g. 6V) with
> > diode
> > > based rectifiers are? If it is high enough so that a DC/DC switching
> regulator
> > > like the LM2574-5.0 (only about 77% efficiency :-( ) could be used? This
> would
> > > be pretty easy, because the mentioned inductors are very easy to get ...
> >
> > Why do you care so much about efficiency if you are going to feed it
> > from mains voltage anyway?
>
> I have already many devices at home that run 24hours a day (2 video recorder,
> sat receiver, TV`s, ...) and I want to reduce costs ... So, why waste lots of
> energy for *nothing* ????? (I have more efficient possibilities to heat my
> rooms ;-) )
>
>Don't worry Shane - when you get right down to it, we are all just
>pieces of code (fairly complex ones, too) - from our DNA down to our
>snappy little synapses and neurons.
Ho hum - here we go again. "We are all just pieces of code". How many [OT]
messages will this invoke concerning the nature of conciousness and whether
or not algorithmically-based systems can be aware of their own existence? No
more than this one, I hope. Just read the Penrose books.
iNTERESTING. tHIS iS tHE sAME aDDRESS tHAT aLL oF mIGUEL'S mAIL cOMES
fROM, bUT tHE uRL lOOKS nORMAL. pERHAPS tHEY aRE dOING iT
iNTENTIONALLY.
PJR
Peter Robinson
Canberra Australia
----------
From: Martin R. Green
To: @spam@PICLIST@spam@spam_OUTMITVMA.MIT.EDU
Subject: Re: Correct LIST?
Date: Friday, 5 September 1997 11:11AM
At 12:48 PM 9/5/97 +1000, you wrote:
>iNTERESTING. tHIS iS tHE sAME aDDRESS tHAT aLL oF mIGUEL'S mAIL cOMES
>fROM, bUT tHE uRL lOOKS nORMAL. pERHAPS tHEY aRE dOING iT
>iNTENTIONALLY.
>
>PJR
>Peter Robinson
>Canberra Australia
> ----------
>From: Martin R. Green
>To: TakeThisOuTPICLISTKILLspamspamMITVMA.MIT.EDU
>Subject: Re: Correct LIST?
>Date: Friday, 5 September 1997 11:11AM
>
>
>My God!!!
>
>It's contagious!
Stop it. Weren't you ever told it will make you go blind <g>.
Seriously; can we stop this now?
Regards,
Ross McKenzie
Melbourne Australia
to reply by email remove the "nospam." text from my email address
> aND i tHOUGHT yOU gUYS wERE jOKING aBOUT mIGUEL!
>
>
> mARTIN r. gREEN
> .....elimarRemoveMEbigfoot.com
>
> ps. mY eMAIL sPELL cHECKER cHOKES oN eVERY wORD, i wONDER wHY
> mIGUEL'S dOESN'T?
>
Oddly, my MS one didn't. I don't normally run spell checkers - there
are too many words in this list that are not on it - esp when ppl
start putting code in.
MikeS
<RemoveMEmikesmith_ozspamBeGonerelaymail.net>
> At 12:48 PM 9/5/97 +1000, you wrote:
> >iNTERESTING. tHIS iS tHE sAME aDDRESS tHAT aLL oF mIGUEL'S mAIL cOMES
> >fROM, bUT tHE uRL lOOKS nORMAL. pERHAPS tHEY aRE dOING iT
> >iNTENTIONALLY.
> >
> >PJR
> >Peter Robinson
> >Canberra Australia
> > ----------
> >From: Martin R. Green
> >To: TakeThisOuTPICLISTspamMITVMA.MIT.EDU
> >Subject: Re: Correct LIST?
> >Date: Friday, 5 September 1997 11:11AM
> >
> >
> >My God!!!
> >
> >It's contagious!
>
> Stop it. Weren't you ever told it will make you go blind <g>.
>
> Seriously; can we stop this now?
>
eR, sTOP wHAT?
<sNICKER>
There is a solution, folks. Use MS Word 97 as your mailer program,
and there a cute little feature that turns tHIS into This. Its
'orribly slow and clunky though.
MikeS
<mikesmith_ozEraseMErelaymail.net>
> >
> > Gaming machines are another instance...
> >
> > They have rigorous legal requirements for randomness, I don't
> > know exactly what they are, but I was told by a friend in that
> > industry that their random number algorithms have to under go
> > a very rigorous certification process.
> >
> > And, the algorithms are closely guarded secrets
> > for obvious reasons!.. :-)
> >
> >
> > Ray Gardiner Techinical Director DSP Systems RemoveMErayEraseMEspam_OUTdsp-systems.com
> > private email to:- @spam@rayRemoveMEEraseMEnetspace.net.auhttp://www.dsp-systems.com
>
> Err Well actualy having been involved in the writing of gaming
> machine programs I can assure you that the RN is not as random as
> you might like to belive. Gaming machines have by law to pay out a
> minum percentage of takings and this is calculated over a very large
> number of plays. In order to get a gameing machine approved in the
> UK it must undergo testing from the gaming board who check that it
> is paying out at the correct level. So what might start out as a RN
> is then wieghted to produce the correct level of payout over time.
> Now you know he's doing it on purpose, the quoted text is fine.
> C'mon mIGUEL,
> own up!
>
I wOnDEr IF hE uSEs c Or uNIx, bOtH oF wHicH, oF cOURsE, aRE caSE
sEnsItIve?
I propose that a small fund is established to purchase mIGUEL a keybord which
has both of the shift keys removed at least I could then read his posts
without straining both eyes and brain trying to unscramble this ecentric mix
of upper and lower case strings.
To this end I propose a donation of one pound (English) to commence the fund.
If everone on the list donates a small ammount we can send him a large box of
functional keyboards.
The early evening musings of a scrambled mind
Steve.....
Mike Smith wrote:
> Use a lava lamp. Makes the gaming machine look nice as well.
Check out this site for a group that seriously uses lava lamps to
generate random numbers: http://lavarand.sgi.com/
--Matt
WF AUTOMA‚ÌO wrote:
>
> Matt Bonner wrote:
> >
> > John Shreffler wrote:
> > >
> > > nice site, WF. Now, your second project should be to look at your cap lock.
> > >
> > <snip>
> > >
> > > ---------------------------------------------------------------
> > >
> > > Part 1.2 Type: application/ms-tnef
> > > Encoding: base64
> >
> > And your priority should be to get rid of MS Mailer attachments. :-(
>
> hUUUU! i wILL sEE!
>
> Miguel.
See what? The light of day? Or a backhand throught the monitor? Now
thats a thought! A physical Flame!
Wooof! Smack! ...ehehehe
<G>
Maybe someone would be so kind as to snailmail (or e-mail...<g>) a caps
lock key to mIGUEL.
Actually, they may get noticed, but in my case the content of them also
gets ignored. In fact I was just thinking of adding his address to my kill
file.
WF AUTOMACAO wrote:
>
> Matt Bonner wrote:
> >
> > John Shreffler wrote:
> > >
> > > nice site, WF. Now, your second project should be to look at your
cap lock. {Quote hidden}
> > >
> > <snip>
> > >
> > > ---------------------------------------------------------------
> > >
> > > Part 1.2 Type: application/ms-tnef
> > > Encoding: base64
> >
> > And your priority should be to get rid of MS Mailer attachments. :-(
>
> hUUUU! i wILL sEE!
>
> Miguel.
See what? The light of day? Or a backhand throught the monitor? Now
thats a thought! A physical Flame!
Wooof! Smack! ...ehehehe
<G>
Maybe someone would be so kind as to snailmail (or e-mail...<g>) a caps
lock key to mIGUEL.
< From: Steve Smith >
> I propose that a small fund is established to purchase mIGUEL a keybord
which
> has both of the shift keys removed at least I could then read his posts
> without straining both eyes and brain trying to unscramble this ecentric
mix
> of upper and lower case strings.
>
> To this end I propose a donation of one pound (English) to commence the
fund.
>
> If everone on the list donates a small ammount we can send him a large
box of
> functional keyboards.
>
Good idea,
I'll donate US$5 and at least four semi functioning AT
keyboards just to find out why that was happening.
He is now relaxing on an island in the tropics with $400K and a box of
keyboards.
....at last a new form of net scam !
< From: Steve Smith >
> I propose that a small fund is established to purchase mIGUEL a keybord
which
> has both of the shift keys removed at least I could then read his posts
> without straining both eyes and brain trying to unscramble this ecentric
mix
> of upper and lower case strings.
>
> To this end I propose a donation of one pound (English) to commence the
fund.
>
> If everone on the list donates a small ammount we can send him a large
box of
> functional keyboards.
>
> If everone on the list donates a small ammount we can send
> [Miguel] a large box of functional keyboards.
According to the PC standard, his keyboard _is_ functional.
The keyboard has a latching "caps lock" key. And it has a
non-latching "up shift" key. When neither is down, letters
are entered in lower case. When either is down, letters are
in upper case.
On a type writer or a real computer, it's a logical OR
function. When both are down (shift lock OR up shift
OR both), letter keys generate capitols. This is what
people expect.
On the PC, it's a logical XOR function. When both are
down (caps lock AND up shift), pressing a letter key
gets you a lower case letter. I have always considered
this a bug (not a feature) in the PC keyboard driver.
Roger Penrose is an eminent British mathematician who has written a
book, The Emperor's New Mind (concerning computers, minds, and the laws
of physics), attacking the idea that computers will ever achieve
consciousness. It's well worth reading.
I like [OT} discussions on the piclist, if they are things that other
PIC'ers would find interesting and don't become excessive. I get a lot of
valuable information that way. I don't have time to subscribe to other
lists. I am currently working on a project for a client which is my first
PIC project and I'm doing well with it. I think an [OT] discussion on the
piclist helped me solve a problem that is indirectly related to PIC's. My
project is currently in a breadboard state, wired with through-hole parts
on perfboard. The pre-production prototypes and the production units will
be SMT (Surface Mount Technology). I wondered how I would solder those tiny
parts onto the circuit board as that would be very difficult for me.
Through reading an [OT] thread on the piclist, I plan, when I get that far,
to buy a toaster oven, a temperature controller and a syringe of solder
paste.
One question: If I end up having to solder parts onto both sides of the
board, how do I keep the ones on the bottom from falling off? Are all SMT
parts the same height, so that the oven tray will hold them in place until
they cool off? Any suggestions are welcome.
>
> Actually, they may get noticed, but in my case the content of them also
> gets ignored. In fact I was just thinking of adding his address to my kill
> file.
>
> Martin R. Green
> RemoveMEelimarEraseMEKILLspambigfoot.com
>
> Ps. that is of course, a mail kill file, not a hit-list...
>
> hhhhmmmmmm...
>
> Nahhh!
>
> ----------
> From: Eric van Es[SMTP:spamBeGonevanesspam_OUTRemoveMEILINK.NIS.ZA]
> Sent: Friday, September 05, 1997 5:34 PM
> To: .....PICLISTRemoveMEmitvma.mit.edu
> Subject: Re: Correct LIST? [ot]
>
> WF AUTOMACAO wrote:
> >
> > Matt Bonner wrote:
> > >
> > > John Shreffler wrote:
> > > >
> > > > nice site, WF. Now, your second project should be to look at your
> cap lock.
> > > >
> > > <snip>
> > > >
> > > > ---------------------------------------------------------------
> > > >
> > > > Part 1.2 Type: application/ms-tnef
> > > > Encoding: base64
> > >
> > > And your priority should be to get rid of MS Mailer attachments. :-(
> >
> > hUUUU! i wILL sEE!
> >
> > Miguel.
>
> See what? The light of day? Or a backhand throught the monitor? Now
> thats a thought! A physical Flame!
> Wooof! Smack! ...ehehehe
>
> <G>
> Maybe someone would be so kind as to snailmail (or e-mail...<g>) a caps
> lock key to mIGUEL.
>
> But then again - his messages do get noticed!
> Cheers!
> --
> Eric van Es | Cape Town, South Africa
> vanes@spam@ilink.nis.za | http://www.nis.za/~vanes
> LOOKING FOR TEMPORARY / HOLIDAY ACCOMODATION?
> http://www.nis.za/~vanes/accom.htm
> One question: If I end up having to solder parts onto both sides of the
> board, how do I keep the ones on the bottom from falling off? Are all SMT
> parts the same height, so that the oven tray will hold them in place until
> they cool off? Any suggestions are welcome.
Glue [or other similar adhesive]. Actually it's recommended for the parts
on both sides of the board, since otherwise parts might move slightly when
the board is put into or removed from the oven.
At 09:29 AM 9/6/97 -0400, you wrote:
> The pre-production prototypes and the production units will
>be SMT (Surface Mount Technology). I wondered how I would solder those tiny
>parts onto the circuit board as that would be very difficult for me.
>Through reading an [OT] thread on the piclist, I plan, when I get that far,
>to buy a toaster oven, a temperature controller and a syringe of solder
>paste.
I have been folowing this thread on SMT soldering using a toaster oven and
it fascinates me. I do non-SMT soldering, of course, but I have never done
surface mount soldering. It sounds like this hybrid toaster over machine is
just going to flow solder over the board and let it stick only to the
traces and component leads. Is this correct? If so, is it going to actually
FLOW the solder over the board or will the board just sit in a pool of
molten solder(doesn't sound too good for the components!!)??
If it is going to keep the solder moving, then how?
I am just generally interested in how this thing will work. Also, if there
will be through hole components on the boars also, do they have to be
soldered after the SMT or can they also be soldered at the same time as the
SMT?
Thanks,
Sean
Sean Breheny,KA3YXM
Electrical Engineering Student
On Sat, 6 Sep 1997 10:40:54 -0400 Sean Breheny <EraseMEshb7RemoveMESTOPspamCORNELL.EDU> writes:
>At 09:29 AM 9/6/97 -0400, you wrote:
>> The pre-production prototypes and the production units will
>>be SMT (Surface Mount Technology). I wondered how I would solder
>those tiny
>>parts onto the circuit board as that would be very difficult for me.
>>Through reading an [OT] thread on the piclist, I plan, when I get
>that far,
>>to buy a toaster oven, a temperature controller and a syringe of
>solder
>>paste.
If your hands are steady and your eyesight reasonably acute, you can
solder typical "coarse" SMT parts such as SOICs, 1206 and 0805 chip
parts, SOT-23 transistors, etc. one at a time by hand using conventional
soldering techniques. I haven't tried it and probably would not
reccomend it for parts with lead spacing smaller than .04" like QFPs,
etc.
The minimum and usually adequate equipment includes: a pencil soldering
iron with a reasonably small tip (1/16 or 3/32 chisel), a roll of
small-diameter wire solder, a pair of tweezers, and some desoldering
braid. Liquid rosin flux and a magnifying glass are also useful
sometimes. If the board or parts have become a little corroded, apply
liquid flux to all the pads so they will take solder readily.
For chip components, first put a little blob of solder on one of the
pads. Pick up the component with tweezers and slide it in position while
remelting the blob of solder. Then solder the other end down. Don't use
too much solder, manufacturers advise that getting solder up over the top
of a chip component can make it unreliabale. If there are a lot of chip
components all facing the same direction, you can streamline the process,
first blob one end of each component, then place the components, then
turn the board around and solder the other ends. With a little practice,
SMT resistors and capacitors can be installed a lot faster than thru-hole
ones.
To remove chip components, the best technique is to use two soldering
irons to melt both ends at once and lift the component away, Clean all
the solder from one end using solder braid, leaving the other end
"blobbed" to install the replacement component. Advice is not to reuse
parts that have been removed. You'll probably lose them in the carpet
anyway.
The technique for SOT transistors and other 3-legged beasties is the same
as chip components, only there are two small pads on one side. Blob the
collector pad and tack the part down, then carefully solder the other 2.
Use only a small amount of solder so they don't bridge. If they do end
up bridged, remove the excess with solder braid.
For ICs, blob one corner pad and tack the part down so the other pins
line up. Double-check that it is the right IC and in the right
orientation. Solder the other corner lead down. Using an absolute
minimum of solder, solder the rest of the leads. It may appear that the
soldering iron tip is too large. Actually it is OK to touch and melt
more than one pin at a time as long as there isn't enough solder around
to bridge them. The important thing to control is the quantity of
solder. Clean the iron tip frequently on a sponge so it doesn't
accumulate a blob of solder. Think of the soldering iron as a source of
heat, not a device that applies solder.
Solder paste helps to speed up the process by making it easy to apply a
small controlled amount of solder. Apply a thin line of solder paste
under each row of pins before setting the chip down, then mash away with
the soldering iron to melt it 2 or 3 pins at a time. Buy solder paste in
small quantities. It is perishable and will become useless after about 6
months.
PLCC chips are similar, but a lot harder to keep the solder from bridging
under the chip. After soldering, test all adjacent pins with an ohmmeter
and if any shorts are found use desolder braid to pull some of the excess
out from under the chip.
Removal of ICs is difficult. Start by using solder braid to remove as
much solder as possible. If the IC is under 20 pins it may be possible
to use two soldering irons and braid to distribute the heat to melt all
the pins free at once. If not, heat each pin and use a dental pick or
large sewing needle to bend it slightly so it is clear of the board.
When the part is off, clean the remaining little bumps of solder off the
pads.
There is a kit inclucing a bismuth alloy to form a low melting mess of
all the solder, so it will stay melted on all the pins and the IC can be
removed. I haven't tried it. {Quote hidden}
>
>I have been folowing this thread on SMT soldering using a toaster oven
>and
>it fascinates me. I do non-SMT soldering, of course, but I have never
>done
>surface mount soldering. It sounds like this hybrid toaster over
>machine is
>just going to flow solder over the board and let it stick only to the
>traces and component leads. Is this correct? If so, is it going to
>actually
>FLOW the solder over the board or will the board just sit in a pool of
>molten solder(doesn't sound too good for the components!!)??
Commercial SMT assembly uses a metal mask to screen solder paste onto the
pads to be soldered (Solder paste is a mixture of fine particles of
solder and flux). Then the parts are set onto the board with their leads
pushed down into the solder paste. The reflow oven applies a dry heat to
melt the solder paste and cause it to reflow onto the parts. The flux is
washed off.
> If it is going to keep the solder moving, then how?
>I am just generally interested in how this thing will work. Also, if
>there
>will be through hole components on the boars also, do they have to be
>soldered after the SMT or can they also be soldered at the same time
>as the
>SMT?
This is another technique, the SMT parts are glued in place to the solder
side of the board, the thru-hole parts placed, and the board goes through
a conventional soldering machine. The components do indeed "sit in a
pool of molten solder." They are designed to withstand it.
Try MAXIM they do all maner of protocol converters or use a MAX232 + LTC485
this does 232 to TTL then TTL to 485 and not very expensive.
Another thaught We buy a PLC from Cuttler Hammer in the UK but its made by
Samsung and supplied with the software is a RS232 / RS485 converter in one of
those tiny boxes that takes just two 9 pin D type connecters about 25mm *
12mm not entirly sure what configuration it is but it does contain both of
the above chips and is line powered.
> On a type writer or a real computer, it's a logical OR function. When
> both are down (shift lock OR up shift OR both), letter keys generate
> capitals. This is what people expect.
I wonder what people "expect" this? Aged typists? Let's not confuse
a limitation of mechanical typewriters, getting pretty rare now, with
some sort of ergonomic feature. The Shift Lock function related to a
limitation whereby it was only practical to make it operate on all keys
at once, and toggles added complexity. The Caps Lock (AKA: Alpha Lock)
on a REAL computer whether PC or otherwise is a *brilliant* feature.
> On the PC, it's a logical XOR function. When both are down (caps lock
> AND up shift), pressing a letter key gets you a lower case letter.
My other machine uses the German overlay (why? You may ask? Well, my
dad picked up a rather high quality, that is, real Japanese manufacture,
German keyboard and I've used it ever since) which amuses me no end.
Hash is an unshifted character, as are beta (s-tzet) and umlauts, and
mu, "squared" and a few other novelties are available as shifted. In
addition, caret and single quotes are prefix keys which make up accented
vowels.
So far so good on this, but while it is OK that the shift lock is un-
locked by the shift key, some MORON in the code page department of you-
know-what organisation has decided that it is, cretinous typewriter-
style, truly a SHIFT Lock for ALL keys.
> I have always considered this a bug (not a feature) in the PC
> keyboard driver.
I challenge Lee to try typing on this German keyboard awhile and see
whether he would not rather keep the caps lock toggle and XOR function!
Put another way, does anyone know whether bug-fixed keyb.sys and
kbdgr.dll (WIN95) files are available?
Mike Keitz wrote:
>
> Removal of ICs is difficult. Start by using solder braid to remove as
> much solder as possible. If the IC is under 20 pins it may be possible
> to use two soldering irons and braid to distribute the heat to melt all
> the pins free at once. If not, heat each pin and use a dental pick or
> large sewing needle to bend it slightly so it is clear of the board.
> When the part is off, clean the remaining little bumps of solder off the
> pads.
Good advice Mike! I actually enjoyed reading a rather long mail!
I once spoke to a guy who had to desolder and solder smt componenets
without the special equipment for the componenets. Apparently you get a
soldering iron tip that fit over an ic, ie one for 20, 40 pin etc.
Only very expensive....
He ended up using a scalpel to lift the IC's from their pads. It sounded
like it worked pretty good.
> > Removal of ICs is difficult. Start by using solder braid to remove as
> > much solder as possible. If the IC is under 20 pins it may be possible
> > to use two soldering irons and braid to distribute the heat to melt all
> > the pins free at once. If not, heat each pin and use a dental pick or
> > large sewing needle to bend it slightly so it is clear of the board.
> > When the part is off, clean the remaining little bumps of solder off the
> > pads.
> I once spoke to a guy who had to desolder and solder smt componenets
> without the special equipment for the componenets. Apparently you
> get a soldering iron tip that fit over an ic, ie one for 20, 40 pin
> etc. Only very expensive....
>
> He ended up using a scalpel to lift the IC's from their pads. It
> sounded like it worked pretty good.
Guys:
Here's another way that often works better AND doesn't bend the IC
leads (a necessary requirement if, for instance, you're removing a
surface-mount PIC for the purpose of putting it in a programmer and
verifying its contents):
1. DON'T use solder braid to "remove as much solder as
possible". Instead, ADD solder: Lay down a thick bridge of
solder across all the leads on each side of the IC.
2. Turn the board upside-down. Gravity is your friend.
3. Heat the leads on one side of the IC a little, then heat the
leads on the other side. Switch back and forth between the
two sides, heating each a little at a time, until both sides
melt more-or-les simultaneously.
4. The IC will drop off the board onto your bench. The force of
the impact will knock nearly all the molten solder off the
IC's leads... The small amount that remains can be removed
with solder braid.
If the chip is glued to the board, of course, you'll need to break
the adhesive bond... A dental pick or small screwdriver GENTLY wedged
under one side of the chip (AFTER the solder is melted) will snap
the chip free from the board without bending the leads.
>> On a type writer or a real computer, it's a logical OR function. When
>> both are down (shift lock OR up shift OR both), letter keys generate
>> capitals. This is what people expect.
I used "shift lock" when meaning "caps lock" in an attempt
to add variety of word usage. This was a mistake. I should
have said "(caps lock OR up shift OR both)" in the above.
> I wonder what people "expect" this? Aged typists?
Maybe people who can read the keycaps. All my keyboards
label the caps lock key as "caps lock". From this legend,
I believe it _should_ mean that you are locking the letter
portion of the keyboard in an upper case state.
> The Caps Lock (AKA: Alpha Lock) on a REAL computer whether
> PC or otherwise is a *brilliant* feature.
I agree. I don't know why the PC keyboard driver writers
broke a well defined function (caps lock == upper case alpha).
>> On the PC, it's a logical XOR function. When both are down (caps lock
>> AND up shift), pressing a letter key gets you a lower case letter.
> My other machine uses the German overlay [...] Hash is an
> unshifted character, as are beta (s-tzet) and umlauts, and
> mu, "squared" and a few other novelties are available as
> shifted. In addition, caret and single quotes are prefix
> keys which make up accented vowels.
I don't know sufficient German to address these specifics.
> So far so good on this, but while it is OK that the shift lock
> is un-locked by the shift key, some MORON in the code page
> department of you-know-what organisation has decided that it is,
> cretinous typewriter-style, truly a SHIFT Lock for ALL keys.
Ah, another "feature" that we can thank them for.
>> I have always considered this a bug (not a feature) in the PC
>> keyboard driver.
> I challenge Lee to try typing on this German keyboard awhile and see
> whether he would not rather keep the caps lock toggle and XOR function!
And I challenge Paul to explain why proper caps lock
functionality can't be considered part of the national
language setup and keyboard mappings!
The caps lock and up shift keys can certainly behave
differently for US and for German keyboards. Each can
provide the most "natural" functionality for the native
speakers (typers?) of that language.
Lee Jones
>Roger Penrose is an eminent British mathematician who has written a
>book, The Emperor's New Mind (concerning computers, minds, and the laws
>of physics), attacking the idea that computers will ever achieve
>consciousness. It's well worth reading.
And don't forget the sequel "Shadows Of The Mind" (1994), which corrects some
shortcomings of the original and answers many criticisms.
He was also responsible for working out the details of Black Hole theory with
some bloke called Hawking through 1965-1970.
> >> On a type writer or a real computer, it's a logical OR function. When
> >> both are down (shift lock OR up shift OR both), letter keys generate
> >> capitals. This is what people expect.
>
> I used "shift lock" when meaning "caps lock" in an attempt
> to add variety of word usage. This was a mistake. I should
> have said "(caps lock OR up shift OR both)" in the above.
>
> > I wonder what people "expect" this? Aged typists?
>
> Maybe people who can read the keycaps. All my keyboards
> label the caps lock key as "caps lock". From this legend,
> I believe it _should_ mean that you are locking the letter
> portion of the keyboard in an upper case state.
>
> > The Caps Lock (AKA: Alpha Lock) on a REAL computer whether
> > PC or otherwise is a *brilliant* feature.
>
> I agree. I don't know why the PC keyboard driver writers
> broke a well defined function (caps lock == upper case alpha).
>
> >> On the PC, it's a logical XOR function. When both are down (caps lock
> >> AND up shift), pressing a letter key gets you a lower case letter.
<snip>
Ok what you're saying is it should be a logical OR that gives CAPS,
but only the shifts should give you !@#$% etc. What I find annoying
(I'm NOT a touch typist) is when I flick the caps lock on
accidentally AND FIND i'VE TYPED A SENTENCE mIGUEL STYLE and have to
erase it!! To prevent this scenario, I've prised the caps lock
keytop off. You can still press it, but its harder to do
accidentally.
Someone must have written a fixed kbd.sys or whatever - I'm 1/2
surprised that the feature isn't settable in the control panel -
every other bloody thing is. It probably is a bit setting in the
registry, to think of it - anyone got the compleat book of the
registry, or whatever?
MikeS
<mikesmith_ozspam_OUTrelaymail.net>
> If your hands are steady and your eyesight reasonably acute, you can
> solder typical "coarse" SMT parts such as SOICs, 1206 and 0805 chip
> parts, SOT-23 transistors, etc. one at a time by hand using conventional
> soldering techniques. I haven't tried it and probably would not
> reccomend it for parts with lead spacing smaller than .04" like QFPs,
> etc.
There is a way... You can solder any SMD IC like this:
1) Solder (sOLDER for mIGUEL) two opposite pins onto the pads to lock
the
IC into place.
2) Wet all the pins with flux to ensure good joints (not the Jamaican
type, man).
3) Roll a big blob of solder to and fro accross the pins.
4) Clear all the bridges with solder braid
> The minimum and usually adequate equipment includes: a pencil soldering
> iron with a reasonably small tip (1/16 or 3/32 chisel), a roll of
> small-diameter wire solder, a pair of tweezers, and some desoldering
> braid. Liquid rosin flux and a magnifying glass are also useful
> sometimes. If the board or parts have become a little corroded, apply
> liquid flux to all the pads so they will take solder readily.
If you use the above method, you don't even need any special tips. (You
should see mine...)
>
> For chip components, first put a little blob of solder on one of the
> pads. Pick up the component with tweezers and slide it in position while
> remelting the blob of solder. Then solder the other end down. Don't use
> too much solder, manufacturers advise that getting solder up over the top
> of a chip component can make it unreliabale. If there are a lot of chip
> components all facing the same direction, you can streamline the process,
> first blob one end of each component, then place the components, then
> turn the board around and solder the other ends. With a little practice,
> SMT resistors and capacitors can be installed a lot faster than thru-hole
> ones.
I fully agree here...
> To remove chip components, the best technique is to use two soldering
> irons to melt both ends at once and lift the component away, Clean all
> the solder from one end using solder braid, leaving the other end
> "blobbed" to install the replacement component. Advice is not to reuse
> parts that have been removed. You'll probably lose them in the carpet
> anyway.
And here...
>
> Removal of ICs is difficult. Start by using solder braid to remove as
> much solder as possible. If the IC is under 20 pins it may be possible
> to use two soldering irons and braid to distribute the heat to melt all
> the pins free at once. If not, heat each pin and use a dental pick or
> large sewing needle to bend it slightly so it is clear of the board.
> When the part is off, clean the remaining little bumps of solder off the
> pads.
If you are going to scrap the PCB, there is a fast and safe (for the IC)
way. Turn the board upside down (IC facing down). Heat the top of the
PCB with a really hot heat gun and watch your undamaged drop onto your
desk. Gasp and run to open all the windows (PCB's are generally not made
to smell good at high temperatures.)
--
Friendly Regards
Tjaart van der Walt RemoveMEtjaartKILLspam@spam@wasp.co.za
________________________________________________________
| WASP International http://wasp.co.za |
| R&D Engineer : GSM peripheral services development |
|Vehicle tracking | Telemetry systems | GSM data transfer|
|Voice : +27-(0)11-622-8686 | Fax : +27-(0)11-622-8973 |
| WGS-84 : 26010.52'S 28006.19'E |
|________________________________________________________|
Andrew Russell Morris wrote:
>
> One question: If I end up having to solder parts onto both sides of the
> board, how do I keep the ones on the bottom from falling off? Are all SMT
> parts the same height, so that the oven tray will hold them in place until
> they cool off? Any suggestions are welcome.
Hey, those are two questions! ;)
The one side of the PCB is laid out to contain all the through-hole
components, and most of the SMD's. This side is soldered by a process
called
reflow. This is basically an oven with a conveyor belt running through
it (a
bit like some high volume Pizza ovens).
The rest of the SMD components (*NOT* through holes) are arranged (and
glued)
on the other side in rows so their leads are lined up. The board is held
with
this side facing down over a solder bath. A wave is created in the bath
and
this runs under the board soldering the components as it travels from
one
side to the other (See why you need glue?).
This is called wave soldering.
Never put though hole components on both sides of the board even if your
friendly manufacturer assures you it is possible.
Try to keep your component count as low a possible by using, for
instance,
resistor arrays in stead of discrete resistors. These arrays are more
expensive than the discretes, but the component cost is small in
relation
to the placement costs (per component).
Try to avoid using through hole components. The placement costs are high
and you pay per pin, where with SMD's you pay per component.
Use the smallest components your manufacturer can handle. The higher
cost
is paid for by the savings on PCB and enclosure costs. You'll see that
these last two often-overlooked aspects often consistute more than half
the total cost.
--
Friendly Regards
Tjaart van der Walt tjaartspamBeGone.....wasp.co.za
________________________________________________________
| WASP International http://wasp.co.za |
| R&D Engineer : GSM peripheral services development |
|Vehicle tracking | Telemetry systems | GSM data transfer|
|Voice : +27-(0)11-622-8686 | Fax : +27-(0)11-622-8973 |
| WGS-84 : 26010.52'S 28006.19'E |
|________________________________________________________|
Andrew Russell Morris wrote:
>
> One question: If I end up having to solder parts onto both sides of the
> board, how do I keep the ones on the bottom from falling off? Are all SMT
> parts the same height, so that the oven tray will hold them in place until
> they cool off? Any suggestions are welcome.
You'll need to support the pcb along the edges so that the bottom of
the pcb is not in contact with a tray, etc. The surface tension of the
solder paste will hold the components on the bottom side of the pcb,
unless thet are very heavy. In that case it will be necessary to use
component glue for those parts. Hint, put all the large components on
the top side of the pcb.
When using a toaster oven, ensure that the temperature of the oven is less
than 80 degs C, before placing the pcb in. Then, turn on the oven, with the
temperature of the controller set to, say 209 degs C. When the temp is
reached, the controller will switch off the heating element. Open the door
and let is cool for a while before removing.
Note: the toaster should be a "Fan Forced" one so that the temperature is
consistent throughout the oven.
I hope this helps.
Peter.
--
Peter Homann email: KILLspampeterh.....adacel.com.au Work : +61 3 9596-2991
Adacel Pty Ltd Fax : +61 3 9596-2960
250 Bay St, Brighton 3186, VIC, AUSTRALIA Mobile : 014 025-925 http://www.adacel.com.au Australian Software Engineering Excellence
I had like to drive a plotter which uses RS232 protocol. When using
Hyperterminal, things are working fine, except that it sends ASCII. I am
using: Send text file. Is there any other soft, or perhaps in Hypert.,
to drive my plotter like Hyperterminal does, but with binary transfer?
Thanks a lot.
At 01:18 PM 9/8/97 +0200, you wrote:
>Hi all,
>
> I had like to drive a plotter which uses RS232 protocol. When using
>Hyperterminal, things are working fine, except that it sends ASCII. I am
>using: Send text file. Is there any other soft, or perhaps in Hypert.,
>to drive my plotter like Hyperterminal does, but with binary transfer?
>Thanks a lot.
I presume you have a file with the plot commands in it.
Try this:
C:> COPY filename COM1 /B
The /B is the key - it goes out in pure binary then.
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware & Software for Industry & R/C Hobbies
"Go fast, turn right, and keep the wet side down!"
==================================================================
>
> At 01:18 PM 9/8/97 +0200, you wrote:
> >Hi all,
> >
> > I had like to drive a plotter which uses RS232 protocol. When using
> >Hyperterminal, things are working fine, except that it sends ASCII. I am
> >using: Send text file. Is there any other soft, or perhaps in Hypert.,
> >to drive my plotter like Hyperterminal does, but with binary transfer?
> >Thanks a lot.
>
> I presume you have a file with the plot commands in it.
>
> Try this:
>
> C:> COPY filename COM1 /B
>
> The /B is the key - it goes out in pure binary then.
>
> Andy
>
> ==================================================================
> Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
> Hardware & Software for Industry & R/C Hobbies
> "Go fast, turn right, and keep the wet side down!"
> ==================================================================
Yes, but I have to change the baud rate. I will try with MODE this
evening. My problem is my plotter, it only has 40 word fifo, and the
upload soft has to stop when it tells STOP, not a word after, or it will
be lost. That's the key of the problem :(
> At 08:12 AM 9/8/97 -0300, you wrote:
> >Hi Sean and others,
> >
> >I'm sorry to don't express myself the better way, but you know, for us who
> >doesn't born speaking english, is a little harder.
>
> Hey, I wasn't born speaking English either, even though I grew up in
> USA. Crying was the only thing I knew to do. But it worked <G>!
Not sure if you do now. Say "Aluminium" <g>
>
> We don't mind if you write well. After all, you show a lot more
> incentive than most on the net. If the net was Spanish- or German-
> or Italian- or etc. -based, how many of us would use it? Probably
> not too many.
>
True. None of us are Flauberts.
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
> Yes, but I have to change the baud rate. I will try with MODE
>this
>evening. My problem is my plotter, it only has 40 word fifo, and the
>upload soft has to stop when it tells STOP, not a word after, or it
>will
>be lost. That's the key of the problem :(
Engage the "hardware flow control" at both ends. In Winodws 95, go
through Control Panel - System - Device Manager - Ports (COM and LPT) -
Communications Port (COMx) - Port Settings, then pull down the flow
control box and select Hardware. If the plotter protocol is ASCII text,
which could be determined by looking at the file, then "Send Text File"
from a terminal program should work.
The DOS com drivers used to always use and require hardware flow control.
For a slow device like a plotter, use a ,P option in the mode setting.
This gives extra timeout time.
The cable needs to have the flow control connections wired. A "3-wire"
cable having only send, receive, and ground won't work. The important
wire is RTS (plotter) - CTS (PC) which is pin 5 of a 25-pin connector if
the plotter is wired as DCE. When this signal is inactive, the PC will
stop sending. The plotter will likely drive it without any special setup
but you may need to reconfigure it. One of those monitor boxes with a
LED connected to each signal is useful in situations like this.
> Yes, but I have to change the baud rate. I will try with MODE this
>evening. My problem is my plotter, it only has 40 word fifo, and the
>upload soft has to stop when it tells STOP, not a word after, or it will
>be lost. That's the key of the problem :(
What kind of plotter? I use this with several HP plotters (from A-size
flatbed to DraftPro EXL), and only requirement is hw handshaking.
Sure you got the right cable and MODE settings?
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware & Software for Industry & R/C Hobbies
"Go fast, turn right, and keep the wet side down!"
==================================================================
No, not exactly. You can download the software, documentation, and
instructions for making the connecting cable for free from Parallax
(http://www.parallax-inc.com). While the SW is normally a commercial product,
parallax's primary interest is in selling stamps, and this is something
they do to lower the entry cost for hobbyists and very small companies.
I think it's very nice of them.
Parallax also maintains a separate mailing list "just about stamps".
Andrew G Williams <RemoveMEAGW01RemoveMEEraseMEAOL.COM> wrote:
> In what way is changing the settings of my own system clock unethical?
> I'm not altering a single byte of program code.
The following comments assume the abscence of a license agreement:
The mere act of setting the clock of your computer back is not illegal, and
probably everyone would agree that it is not unethical.
It is well-established legally (at least in the US) that the consumer has the
right to make any desired alterations to purchased products. This includes
patching object code. It has even been found that any interim copies which are
made solely as a necessary step in the alteration are covered as fair use.
I would argue that patching per se is not unethical.
However, I personally consider it to be unethical to either set back the clock
or to patch out the checking in order to circumvent the author's intended
restrictions on a trial version of a software package.
IMHO, if the software is worth using, it is worth buying.
William Chops Westfield wrote:
>
> > > Is it the BASIC STAMP1 Software Freeware?
>
> No, not exactly. You can download the software, documentation, and
> instructions for making the connecting cable for free from Parallax
> (http://www.parallax-inc.com). While the SW is normally a commercial product,
> parallax's primary interest is in selling stamps, and this is something
> they do to lower the entry cost for hobbyists and very small companies.
>
> I think it's very nice of them.
>
> Parallax also maintains a separate mailing list "just about stamps".
>
> BillW
> However, I personally consider it to be unethical to either set back the clock
> or to patch out the checking in order to circumvent the author's intended
> restrictions on a trial version of a software package.
>
> IMHO, if the software is worth using, it is worth buying.
Note, further, that the software activation was obtained by filling out
a license agreement form on Hitech's web site (or otherwise sending HiTech
an agreement); by requesting the serial number you have indicated that you
agree not to use the software for purposes other than those indicated.
At 11:45 PM 9/8/97 +0000, you wrote:
>> Hey, I wasn't born speaking English either, even though I grew up in
>> USA. Crying was the only thing I knew to do. But it worked <G>!
>
>Not sure if you do now. Say "Aluminium" <g>
Hey Mike,
Isn't it "Aluminum" over there in the US? <VBG>
Regards,
Ross McKenzie
Melbourne Australia
to reply by email remove the "nospam." text from my email address
Brief summary of Penrose's position (with which I strongly disagree):
Computers can't have intelligence because they are specifically designed
to avoid randomness due to quantum uncertainty. This was a mostly accidental
(but generally fortuitous) result of using large numbers of electrons, thus
getting statistically predictable behavior.
Humans, on the other hand, use neurons that might possibly demonstrate
macroscopic behavior influenced by quantum uncertainty. Therefore, they
can't be simulated by computers. Therefore computers can't be intelligent.
Obvious problems with his argument:
does human intelligence really depend on quantum uncertainty?
if so, couldn't there be another means to achieve equivalent
intelligence without quantum uncertainty?
As near as I can tell, Penrose believes quantum uncertaintly is necessary
to intelligence because:
all known naturally-occuring forms of inteligence involve quantum
uncertainty
we've never developed intelligent computers (circular reasoning)
we can't predict the behaior of human beings, so they must be
non-deterministic (false, increases in complexity of a system tend
to cause exponential increases in the computation needed to model
the system, so inability to predict the behavior of a system does
not prove that it is non-deterministic)
However, "The Emperor's New Mind" is quite interesting reading even if the
logic underlying his conclusions is incomplete. I haven't read his other
book(s) yet.
>
>When using a toaster oven, ensure that the temperature of the oven is less
>than 80 degs C, before placing the pcb in. Then, turn on the oven, with the
>temperature of the controller set to, say 209 degs C. When the temp is
>reached, the controller will switch off the heating element. Open the door
>and let is cool for a while before removing.
>
Do you turn the oven off and open the door as soon as 209 degrees is
reached, or sometime afterward. I know the the controller will switch off
the heating element at 209 degrees, but it will come back on when the
temperature drops a little, and keep turning on and off, maintaining
temperature at the set point until I turn it off.
I don't want to appear stupid. I think you mean as soon as the controller
switches the heater off for the first time, but I just want to be sure I
understand what you meant. :-)
Andrew Russell Morris wrote:
>
> >
> >When using a toaster oven, ensure that the temperature of the oven is less
> >than 80 degs C, before placing the pcb in. Then, turn on the oven, with the
> >temperature of the controller set to, say 209 degs C. When the temp is
> >reached, the controller will switch off the heating element. Open the door
> >and let is cool for a while before removing.
> >
>
> Do you turn the oven off and open the door as soon as 209 degrees is
> reached, or sometime afterward. I know the the controller will switch off
> the heating element at 209 degrees, but it will come back on when the
> temperature drops a little, and keep turning on and off, maintaining
> temperature at the set point until I turn it off.
>
> I don't want to appear stupid. I think you mean as soon as the controller
> switches the heater off for the first time, but I just want to be sure I
> understand what you meant. :-)
To clarify the above, the oven must be below 50 degs C (120 F) before the
heating cycle is started. This is necessary so that the solder paste can
pass through the point needed to drive of solder paste solvents before
the melting point is reached.
The oven should be switch off when the temperature reaches 219 degs C
(426 F) NOT 209 degs C as above, but the fans should continue to run.
Once the set-point is reached the heater must remain off to allow the
cooling cycle to commence.
I hope this is clearer.
Peter.
--
Peter Homann email: peterhspamadacel.com.au Work : +61 3 9596-2991
Adacel Pty Ltd Fax : +61 3 9596-2960
250 Bay St, Brighton 3186, VIC, AUSTRALIA Mobile : 014 025-925 http://www.adacel.com.au Australian Software Engineering Excellence
Ross McKenzie wrote:
>
> At 11:45 PM 9/8/97 +0000, you wrote:
> >> Hey, I wasn't born speaking English either, even though I grew up in
> >> USA. Crying was the only thing I knew to do. But it worked <G>!
> >
> >Not sure if you do now. Say "Aluminium" <g>
>
> Hey Mike,
>
> Isn't it "Aluminum" over there in the US? <VBG>
I think it is A-lou-mini-uhm <G> And you even get it colours
(oops, I mean colors)
--
Friendly Regards
Tjaart van der Walt RemoveMEtjaartspamBeGoneRemoveMEwasp.co.za
________________________________________________________
| WASP International http://wasp.co.za |
| R&D Engineer : GSM peripheral services development |
|Vehicle tracking | Telemetry systems | GSM data transfer|
|Voice : +27-(0)11-622-8686 | Fax : +27-(0)11-622-8973 |
| WGS-84 : 26010.52'S 28006.19'E |
|________________________________________________________|
> Andrew G Williams <KILLspamAGW01spamBeGoneAOL.COM> wrote:
> > Just read the Penrose books.
>
> Brief summary of Penrose's position (with which I strongly
> disagree):
>
> Computers can't have intelligence because they are specifically
> designed to avoid randomness due to quantum uncertainty. This was a
> mostly accidental (but generally fortuitous) result of using large
> numbers of electrons, thus getting statistically predictable
> behavior.
>
> Humans, on the other hand, use neurons that might possibly
> demonstrate macroscopic behavior influenced by quantum uncertainty.
> Therefore, they can't be simulated by computers. Therefore
> computers can't be intelligent.
>
> Obvious problems with his argument:
>
> does human intelligence really depend on quantum
> uncertainty?
>
> if so, couldn't there be another means to achieve equivalent
> intelligence without quantum uncertainty?
Aren't scientist developing a so called 'quantum effect' computer,
anyway?
>
> As near as I can tell, Penrose believes quantum uncertaintly is
> necessary to intelligence because:
>
> all known naturally-occuring forms of inteligence involve
> quantum uncertainty
Thats like saying - "All life is based on the carbon atom, therefore
life based on other atoms is not possible"
(impossible to prove a negative, isn't it?)
>
> we've never developed intelligent computers (circular
> reasoning)
Kasparov was sounding rather hysterical on the subject.
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
> Andrew G Williams <@spam@AGW01STOPspam@spam@AOL.COM> wrote:
> > In what way is changing the settings of my own system clock unethical?
> > I'm not altering a single byte of program code.
>
> The following comments assume the abscence of a license agreement:
>
> The mere act of setting the clock of your computer back is not
> illegal, and probably everyone would agree that it is not unethical.
>
> It is well-established legally (at least in the US) that the
> consumer has the right to make any desired alterations to purchased
> products. This includes patching object code. It has even been
> found that any interim copies which are made solely as a necessary
> step in the alteration are covered as fair use.
>
> I would argue that patching per se is not unethical.
>
> However, I personally consider it to be unethical to either set back
> the clock or to patch out the checking in order to circumvent the
> author's intended restrictions on a trial version of a software
> package.
>
> IMHO, if the software is worth using, it is worth buying.
Further, that crippling s/w more than having a 'use by' date on it,
is self-defeating for the author, in that it prevents the user from
trying out the code. An instance - A piece of software called CAMCAD
is available for read/modify/write of differing formats of say pcb
artwork. However, it is crippled to the extent where - you can't
edit - you can only read a limited number of formats - you can't
export as a different format. As shareware this is useless - I don't
know if it will let me move a file from one format to another then
into another piece of s/w. All I know about it is that its screen
redraw speed is slow with a complex board (with a fast video system)
- something that does not impel me to register it. If I could try
its other features I might not be swayed by thee speed, and I might
possibly register it - but not as it is. So they have lost a sale.
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
> Brief summary of Penrose's position (with which I strongly disagree):
> Computers can't have intelligence because they are specifically designed
> to avoid randomness due to quantum uncertainty. This was a mostly accidental
> (but generally fortuitous) result of using large numbers of electrons, thus
> getting statistically predictable behavior.
> Humans, on the other hand, use neurons that might possibly demonstrate
> macroscopic behavior influenced by quantum uncertainty. Therefore, they
> can't be simulated by computers. Therefore computers can't be intelligent.
I read the book quite a while ago so I don't remember it well, but I
don't think Penrose's points were those. He rather has a belief (or
at least considers the idea) that our brains are non-deterministic,
and he uses quantum theory to back up this thought, showing a
hypotetical scientifically-approved source for this uncertainity.
> Obvious problems with his argument:
> does human intelligence really depend on quantum uncertainty?
As I said, this is an hipotesis he uses to show that it is physically
possible to have a non-deterministic brain.
> As near as I can tell, Penrose believes quantum uncertaintly is necessary
> to intelligence because:
> all known naturally-occuring forms of inteligence involve quantum
> uncertainty
> we've never developed intelligent computers (circular reasoning)
> we can't predict the behaior of human beings, so they must be
> non-deterministic (false, increases in complexity of a system tend
> to cause exponential increases in the computation needed to model
> the system, so inability to predict the behavior of a system does
> not prove that it is non-deterministic)
You can say that if something can be predicted (to 100% accuracy) by
us then it is deterministic, but the counter-theorem is far from true
and not only because of what you're saying. I don't believe Penrose
will make such a big mistake, you must have misunderstood him. As an
example, the points that don't belong to a Mandlebrot set are
deterministic in nature but they can't be calculated.
Oh, here I am messing with this topic again! I don't think people in
the list will like it, sorry, I promise not to send another message like
this here.
.......snip
Do you turn the oven off and open the door as soon as 209 degrees is
reached, or sometime afterward.
.......snip
Soldering SMT parts in a toaster oven....
I get the screaming heebe-jeebies with every installment of this thread.
I saw a technician that soldered with an electric charcoal grill starter.
He said they just plug it in until it glows cherry red, and wave it over
the board till everything looks soldered.
Component databooks frequently contain a page or two on soldering. The
Motorola data book have good information on temperature profiles and times.
The book contains a graph that looks something like:
preheat to 50 C
increase to 150 C in in first minute
increase to 160 C in the next minute
increase to 170 C in the next minute
increase to 205 C in the next minute
decrease to 50 C in the last minute
>
> Oh, here I am messing with this topic again! I don't think people in
> the list will like it, sorry, I promise not to send another message
> like this here.
Its marked OT - they can't really complain - not with a straight
face, anyway.
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
I was wondering if any of you out there might be able to help.
Some time ago I bought a stack of surplus 7 segment LED's. I'm
wanting to use some in a few PIC projects and such. I have no problem
with most of them but I've got some TIL+311 and have absolutely no
idea how to hook them up. So does any of you out there have a
diagram/datasheet or info for this baby??? If so, could you please
send me a copy (legible ascii art is fine). Thanks.
>
> Hi,
>
> Sorry I don't have a diagram for you, but I have a suggestion.
>
> Have you tried putting one of them in a breadboard, and using a 3V supply
> and a 200R resistor to check out the pins. Connect a random pin to ground
> then connect each pin in turn through the resistor to +3V.
>
> These are the possible outcomes.
>
> Common cathode, gnd not connected to cathode - no segments light up. Connect
> +ve through resistor to pin and probe for cathode.
>
> Common cathode, gnd connected to cathode - lots of segments light up in turn
> (bingo) start writing down pin allocations.
>
> Common anode, gnd connected to anode - no segments light up. Connect +ve
> through resistor to pin and start writing down segmemnts.
>
> Common anode, gnd connected to segment - only one segment lights up. Connect
> +ve to pin which lights segments and start writing down pin allocations.
>
> There may be some pins which are not connected, or which are bridged
> together. If you have a meter in series with the 3V supply it's easy to see
> which ones these are.
>
> Hope this is some help,
>
> Keith.
> ------------------------------------------------------------
> Keith Dowsett "Variables won't; constants aren't."
>
> E-mail: spam_OUTkdowsettSTOPspamrpms.ac.uk or RemoveMEkdowsettspamgeocities.com
>
> WWW: http://kd.rpms.ac.uk/index.htm
> http://www.geocities.com/CapeCanaveral/Lab/8979
>
>
Hi there..again
In response..
That was the first thing I tried and all I managed to locate was the
dp's.
This 7seg has a small chip in it that appears to do some decoding as
each segment actually consists of four individual LED's as such:
+--\/----\/--+ +------------+
| | 14|0 0|1
| o o o o | | |
| o o | 13|0 0|2
| o o | | T |
| o o o o | 12|0 I 0|3
| o o | | L |
| o o | | 3 0|4
|o o o o o o | | 1 |
| | 10|0 1 0|5
| +---+ | | |
| |IC | | | |
| | | | | |
| +---+ | 8|0 0|7
+-----/\-----+ +------------+
Maybe this will shed some light on the problem.
Thanks anyway.
Regards
Jacques Vrey
Iscor Steel Profile Products
Newcastle
South Africa
Tel: +27 (0)3431 48759 TakeThisOuTjvreyspamRemoveMEit.new.iscorltd.co.za
>
> Hi,
>
> Sorry I don't have a diagram for you, but I have a suggestion.
>
> Have you tried putting one of them in a breadboard, and using a 3V supply
> and a 200R resistor to check out the pins. Connect a random pin to ground
> then connect each pin in turn through the resistor to +3V.
>
> These are the possible outcomes.
>
> Common cathode, gnd not connected to cathode - no segments light up. Connect
> +ve through resistor to pin and probe for cathode.
>
> Common cathode, gnd connected to cathode - lots of segments light up in turn
> (bingo) start writing down pin allocations.
>
> Common anode, gnd connected to anode - no segments light up. Connect +ve
> through resistor to pin and start writing down segmemnts.
>
> Common anode, gnd connected to segment - only one segment lights up. Connect
> +ve to pin which lights segments and start writing down pin allocations.
>
> There may be some pins which are not connected, or which are bridged
> together. If you have a meter in series with the 3V supply it's easy to see
> which ones these are.
>
> Hope this is some help,
>
> Keith.
> ------------------------------------------------------------
> Keith Dowsett "Variables won't; constants aren't."
>
> E-mail: KILLspamkdowsettspamspam_OUTrpms.ac.uk or kdowsettRemoveMEgeocities.com
>
> WWW: http://kd.rpms.ac.uk/index.htm
> http://www.geocities.com/CapeCanaveral/Lab/8979
>
>
Hi there..again
In response..
That was the first thing I tried and all I managed to locate was the
dp's.
This 7seg has a small chip in it that appears to do some decoding as
each segment actually consists of four individual LED's as such:
+--\/----\/--+ +------------+
| | 14|0 0|1
| o o o o | | |
| o o | 13|0 0|2
| o o | | T |
| o o o o | 12|0 I 0|3
| o o | | L |
| o o | | 3 0|4
|o o o o o o | | 1 |
| | 10|0 1 0|5
| +---+ | | |
| |IC | | | |
| | | | | |
| +---+ | 8|0 0|7
+-----/\-----+ +------------+
Maybe this will shed some light on the problem.
Thanks anyway.
Regards
Jacques Vrey
Iscor Steel Profile Products
Newcastle
South Africa
Tel: +27 (0)3431 48759 EraseMEjvreySTOPspamRemoveMEit.new.iscorltd.co.za
>
> Have you tried putting one of them in a breadboard, and using a 3V supply
> and a 200R resistor to check out the pins. Connect a random pin to ground
> then connect each pin in turn through the resistor to +3V.
>
> These are the possible outcomes.
> Boom ! (Well almost .)
>
> The TIL-311 is a combined hex decoder / latch display driver.
>
> Jacques - I have sent you an email 1.7MB with the product data sheets...
>
> Regards
> MC
>
> -----Original Message-----
> From: Jacques Vrey [SMTP:EraseMEjvreyRemoveMEIT.NEW.ISCORLTD.CO.ZA]
> Sent: Wednesday, September 10, 1997 4:31 PM
> To: spamPICLIST.....spamMITVMA.MIT.EDU
> Subject: Re: [OT] 7 Segment LED
>
>
> +--\/----\/--+ +------------+
> | | 14|0 0|1
> | o o o o | | |
> | o o | 13|0 0|2
> | o o | | T |
> | o o o o | 12|0 I 0|3
> | o o | | L |
> | o o | | 3 0|4
> |o o o o o o | | 1 |
> | | 10|0 1 0|5
> | +---+ | | |
> | |IC | | | |
> | | | | | |
> | +---+ | 8|0 0|7
> +-----/\-----+ +------------+
>
> Maybe this will shed some light on the problem.
Similar to some HP displays I *had*, should be
BCD encoding + GND + VCC + CS :
Pin 7 - GND
Pin 14 - VCC
1-5 probably digital....
S...
I want to convert a pcb layout file which is in gerber format
to PostScript to print on paper....
S...
See http://WWW.ECAM.com/ Excellent gerber viewer/editor/printer
They have a 7 day timed demo, and untimed (limited) demo.
(It also scales with independant X and Y factors to help compensate for the
paper stretch.)
Joe
>BTW have you tried to make a layout mask using transparency, ink jet
>printer and photoresist, is the quality and contrast acceptable?
>I have tried using laser printer, but have found that the black areas were
>slightly transparent to UV, so the resulting pcb was practicaly unusable.
>I also had no lack using this special transparencies (TES or something else)
>which you iron press on a copper board.
I'm using a HP 820cxi inkjet printer and regular
inkjet transparencies.
I buy PCB's with photoresist, and this works out ok for me.
Generally I don't use track widths less than 0.2 mm.
On the HP printer it seems that more ink is applied if I set the output
quality to maximum and specify "Premium paper" instead of "Transparency"
If I remember correctly (and I might not) the TIL311 is a smart LED, with a
4 character addressable latch. I think these devices were actually 15
segment devices, allowing display of the complete ASCII set. The logic
circuits are 5V TTL. I will check at home to see if I still have info on
these useful, but way expensive devices.
>
> Hi,
>
> Sorry I don't have a diagram for you, but I have a suggestion.
>
> Have you tried putting one of them in a breadboard, and using a 3V supply
> and a 200R resistor to check out the pins. Connect a random pin to ground
> then connect each pin in turn through the resistor to +3V.
>
> These are the possible outcomes.
>
> Common cathode, gnd not connected to cathode - no segments light up.
Connect
> +ve through resistor to pin and probe for cathode.
>
> Common cathode, gnd connected to cathode - lots of segments light up in
turn
> (bingo) start writing down pin allocations.
>
> Common anode, gnd connected to anode - no segments light up. Connect +ve
> through resistor to pin and start writing down segmemnts.
>
> Common anode, gnd connected to segment - only one segment lights up.
Connect
> +ve to pin which lights segments and start writing down pin allocations.
>
> There may be some pins which are not connected, or which are bridged
> together. If you have a meter in series with the 3V supply it's easy to
see {Quote hidden}
In response..
That was the first thing I tried and all I managed to locate was the
dp's.
This 7seg has a small chip in it that appears to do some decoding as
each segment actually consists of four individual LED's as such:
+--\/----\/--+ +------------+
| | 14|0 0|1
| o o o o | | |
| o o | 13|0 0|2
| o o | | T |
| o o o o | 12|0 I 0|3
| o o | | L |
| o o | | 3 0|4
|o o o o o o | | 1 |
| | 10|0 1 0|5
| +---+ | | |
| |IC | | | |
| | | | | |
| +---+ | 8|0 0|7
+-----/\-----+ +------------+
Maybe this will shed some light on the problem.
Thanks anyway.
Regards
Jacques Vrey
Iscor Steel Profile Products
Newcastle
South Africa
Tel: +27 (0)3431 48759 RemoveMEjvreyKILLspamRemoveMEit.new.iscorltd.co.za
> Janusz J. Mlodzianowski wrote:
> >
> > Hi,
> > Sorry, this is slightly off topic.
> > I want to convert a pcb layout file which is in gerber format
> > to PostScript to print on paper. Are there any ready made utilities, with
> > the source code, in Public Domain available? What about GhostScript?
> > BTW have you tried to make a layout mask using transparency, ink jet
> > printer and photoresist, is the quality and contrast acceptable?
> > I have tried using laser printer, but have found that the black areas were
> > slightly transparent to UV, so the resulting pcb was practicaly unusable.
> > I also had no lack using this special transparencies (TES or something else)
> > which you iron press on a copper board.
> > Thanks for comments,
> > Janusz
>
> Try http://www.shareware.com or http://www.simtel.com, a use "CONVERTER" as search
> option!
>
> Miguel.
>
Was the uPPER cASE thing a joke, or a real tech problem, Miguel? The
PICLIST needs to know...
Whilst on the off topic area of postscript, can anyone explain to me
the difference between a print-ready post-script file, and an EPS
(encapsulated post script) file. Where does one obtain the
encapsulant? <g> (or encapsulating file).
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
> >BTW have you tried to make a layout mask using transparency, ink jet
> >printer and photoresist, is the quality and contrast acceptable?
> >I have tried using laser printer, but have found that the black areas
> were
> >slightly transparent to UV, so the resulting pcb was practicaly
> unusable.
> >I also had no lack using this special transparencies (TES or
> something else)
> >which you iron press on a copper board.
>
> I'm using a HP 820cxi inkjet printer and regular
> inkjet transparencies.
>
> I buy PCB's with photoresist, and this works out ok for me.
> Generally I don't use track widths less than 0.2 mm.
>
> On the HP printer it seems that more ink is applied if I set the
> output
> quality to maximum and specify "Premium paper" instead of
> "Transparency"
>
> -Oyvind
Hi Oyvind
I had a HP DeskJet 600 from Oct 96 till last month. I now have a HP 690
C+. From my experiance I can say that all HP's (and probably all
inkjets) use more ink to increase quality. When printing High Quality,
the heads make more passes on the paper's lenght, ie: smaller "pixels"
of ink are deposited. Thus there are more "pixels" and more ink is used.
The result is a page soaked in ink if you use normal (thin) photocopier
paper.
> Soldering SMT parts in a toaster oven....
> I get the screaming heebe-jeebies with every installment of this
> thread.
> I saw a technician that soldered with an electric charcoal grill
> starter.
> He said they just plug it in until it glows cherry red, and wave
> it over
> the board till everything looks soldered.
>
> Component databooks frequently contain a page or two on
> soldering. The
> Motorola data book have good information on temperature profiles
> and times.
>
> The book contains a graph that looks something like:
> preheat to 50 C
> increase to 150 C in in first minute
> increase to 160 C in the next minute
> increase to 170 C in the next minute
> increase to 205 C in the next minute
> decrease to 50 C in the last minute
>
> Joe
And did the boards work?
Probably. The things I have done to get a plant losing 10,000 bucks
every hour running again will also make some peoples hair stand on
edge...
I'm not critisising you, but sometimes one can get away with murder...
>Andrew G Williams <EraseMEAGW01.....KILLspamAOL.COM> wrote:
>> In what way is changing the settings of my own system clock unethical?
>> I'm not altering a single byte of program code.
>
>
> ..... I personally consider it to be unethical to either set back the clock
>or to patch out the checking in order to circumvent the author's intended
>restrictions on a trial version of a software package.
>
>IMHO, if the software is worth using, it is worth buying.
I find it difficult to disagree with that.
It's just as well I prefer assembler! :-)
I sent you a huge email with TI datasheets - and they bounced back at me.... !
Please ask your ISP to get their act together... it hurts getting 1.7Megs of
returned mail !
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
I have no idea how it works, I just know how to use it.
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
Correction, when I reread the original post, I realized that I had spouted
crap, sorry. The TIL311 was a single digit, 7 segment device as you
stated, but it did in fact have an on-chip BCD to 7seg decoder/latch.
As I said, I will try to find the specs on this for you.
----------
From: MARTIN Green
Sent: Wednesday, September 10, 1997 11:01 AM
To: 'pic microcontroller discussion list'
Subject: RE: [OT] 7 Segment LED
If I remember correctly (and I might not) the TIL311 is a smart LED, with a
4 character addressable latch. I think these devices were actually 15
segment devices, allowing display of the complete ASCII set. The logic
circuits are 5V TTL. I will check at home to see if I still have info on
these useful, but way expensive devices.
>
> Hi,
>
> Sorry I don't have a diagram for you, but I have a suggestion.
>
> Have you tried putting one of them in a breadboard, and using a 3V supply
> and a 200R resistor to check out the pins. Connect a random pin to ground
> then connect each pin in turn through the resistor to +3V.
>
> These are the possible outcomes.
>
> Common cathode, gnd not connected to cathode - no segments light up.
Connect
> +ve through resistor to pin and probe for cathode.
>
> Common cathode, gnd connected to cathode - lots of segments light up in
turn
> (bingo) start writing down pin allocations.
>
> Common anode, gnd connected to anode - no segments light up. Connect +ve
> through resistor to pin and start writing down segmemnts.
>
> Common anode, gnd connected to segment - only one segment lights up.
Connect
> +ve to pin which lights segments and start writing down pin allocations.
>
> There may be some pins which are not connected, or which are bridged
> together. If you have a meter in series with the 3V supply it's easy to
see {Quote hidden}
In response..
That was the first thing I tried and all I managed to locate was the
dp's.
This 7seg has a small chip in it that appears to do some decoding as
each segment actually consists of four individual LED's as such:
+--\/----\/--+ +------------+
| | 14|0 0|1
| o o o o | | |
| o o | 13|0 0|2
| o o | | T |
| o o o o | 12|0 I 0|3
| o o | | L |
| o o | | 3 0|4
|o o o o o o | | 1 |
| | 10|0 1 0|5
| +---+ | | |
| |IC | | | |
| | | | | |
| +---+ | 8|0 0|7
+-----/\-----+ +------------+
Maybe this will shed some light on the problem.
Thanks anyway.
Regards
Jacques Vrey
Iscor Steel Profile Products
Newcastle
South Africa
Tel: +27 (0)3431 48759 KILLspamjvreyspam_OUTit.new.iscorltd.co.za
Correction, when I reread the original post, I realized that I had spouted
crap, sorry. The TIL311 was a single digit, 7 segment device as you
stated, but it did in fact have an on-chip BCD to 7seg decoder/latch.
As I said, I will try to find the specs on this for you.
----------
From: MARTIN Green
Sent: Wednesday, September 10, 1997 11:01 AM
To: 'pic microcontroller discussion list'
Subject: RE: [OT] 7 Segment LED
If I remember correctly (and I might not) the TIL311 is a smart LED, with a
4 character addressable latch. I think these devices were actually 15
segment devices, allowing display of the complete ASCII set. The logic
circuits are 5V TTL. I will check at home to see if I still have info on
these useful, but way expensive devices.
>
> Hi,
>
> Sorry I don't have a diagram for you, but I have a suggestion.
>
> Have you tried putting one of them in a breadboard, and using a 3V supply
> and a 200R resistor to check out the pins. Connect a random pin to ground
> then connect each pin in turn through the resistor to +3V.
>
> These are the possible outcomes.
>
> Common cathode, gnd not connected to cathode - no segments light up.
Connect
> +ve through resistor to pin and probe for cathode.
>
> Common cathode, gnd connected to cathode - lots of segments light up in
turn
> (bingo) start writing down pin allocations.
>
> Common anode, gnd connected to anode - no segments light up. Connect +ve
> through resistor to pin and start writing down segmemnts.
>
> Common anode, gnd connected to segment - only one segment lights up.
Connect
> +ve to pin which lights segments and start writing down pin allocations.
>
> There may be some pins which are not connected, or which are bridged
> together. If you have a meter in series with the 3V supply it's easy to
see {Quote hidden}
In response..
That was the first thing I tried and all I managed to locate was the
dp's.
This 7seg has a small chip in it that appears to do some decoding as
each segment actually consists of four individual LED's as such:
+--\/----\/--+ +------------+
| | 14|0 0|1
| o o o o | | |
| o o | 13|0 0|2
| o o | | T |
| o o o o | 12|0 I 0|3
| o o | | L |
| o o | | 3 0|4
|o o o o o o | | 1 |
| | 10|0 1 0|5
| +---+ | | |
| |IC | | | |
| | | | | |
| +---+ | 8|0 0|7
+-----/\-----+ +------------+
Maybe this will shed some light on the problem.
Thanks anyway.
Regards
Jacques Vrey
Iscor Steel Profile Products
Newcastle
South Africa
Tel: +27 (0)3431 48759 TakeThisOuTjvreyKILLspam@spam@it.new.iscorltd.co.za
I'm looking for a cheap half bridge driver, perhaps a MOSFET driver,
that will take a 5 volt input signal and drive a 24 volt motor both
directions.
I discovered the Telcom semiconductor TLC4427 in an old Nuts and
Volts article, and it looked like just what I needed. Hook up
ground, two 5 volt signals, and a higher voltage (up to 22 volts, it
sez here) and you have two pins able to drive a small DC motor.
Not so fast. At 18 volts, the H-bridge shorts out and renders the IC
into a small 8-pin paperwieght. Even with a 13 volt power supply
with a lot of ripple, these things last a few seconds before they
blow, with no load. I think they are worthless at anything over 6
volts.
What do you PICsters use to drive relays and small DC motors?
> >What do you PICsters use to drive relays and small DC motors?
>
> You might take a look at the ULN2003A.
Looks good, except it's an open collector output. I'm trying to
drive a small motor forward and reverse, so I need to find something
that can hook up to the motor in an H-bridge configuration. So far
no luck.
On Wed, 10 Sep 1997, Lawrence Lile wrote:
>
> What do you PICsters use to drive relays and small DC motors?
You can build yr own H-bridge out of discrete transistors -- a
little more expensive than an appropriate IC at low power, but it is the
way to go for higher powers. An H-bridge is a really simple circuit --
it's somewhere in the Art of Electronics along with a complete discussion
of analysis and transistor selection. If you can code assembler, you can
certainly build an H-bridge.
>What do you PICsters use to drive relays and small DC motors?
You might take a look at the ULN2003A. Inexpensive and available. It
contains seven transistors, each able to carry up to 500mA (from memory).
On the relays, make *sure* to use the diode across the coil to capture the
collapsing field. I believe the ULN2003A datasheet is on our web site in
the EDE1200 section. http://www.netins.net/showcase/elab
-Todd Peterson
E-Lab Digital Engineering, Inc.
"Embedded Control & Integrated Circuit Solutions"
EDE300 IC - Stamp I/O Expander & PC Interface IC
EDE700 IC - Serial to LCD Interface IC
EDE1200 IC - Stepper Motor Controller
EDE1400 IC - Serial to Parallel-Printer IC
The TIL311 is a hex display, with a driver circuit able to accept 4 bit
binary data. Data can be latched.
Pin 1 LED supply voltage (+5V)
Pin 2 Latch data input B (Weight = 2)
Pin 3 Latch data input A (Weight = 1)
Pin 4 Left decimal point cathode (you need a series resistor to
limit current)
Pin 5 Latch strobe input (High = inputs latched, Low = follow input data)
Pin 7 Common Ground
Pin 8 Blanking input (High = blank display. You can pulse this input for
LED intensity control)
Pin 10 Right decimal point cathode (you need a series resistor to limit
current)
Pin 12 Latch data input D (Weight = 8)
Pin 13 Latch data input C (Weight = 4)
Pin 14 Logic supply voltage,Vcc (+5V)
> From KILLspamelimarTakeThisOuTBIGFOOT.COM Wed Sep 10 12:11:52 1997
> Encoding: 110 TEXT
> Date: Wed, 10 Sep 1997 11:05:13 -0400
> From: "Martin R. Green" <TakeThisOuTelimarspam_OUTBIGFOOT.COM>
> Subject: FW: [OT] 7 Segment LED
> To: RemoveMEPICLISTspamSTOPspamMITVMA.MIT.EDU
>
> Correction, when I reread the original post, I realized that I had spouted
> crap, sorry. The TIL311 was a single digit, 7 segment device as you
> stated, but it did in fact have an on-chip BCD to 7seg decoder/latch.
>
> As I said, I will try to find the specs on this for you.
>
> Martin R. Green
> .....elimarEraseMEbigfoot.com
>
> ----------
> From: MARTIN Green
> Sent: Wednesday, September 10, 1997 11:01 AM
> To: 'pic microcontroller discussion list'
> Subject: RE: [OT] 7 Segment LED
>
> If I remember correctly (and I might not) the TIL311 is a smart LED, with a
> 4 character addressable latch. I think these devices were actually 15
> segment devices, allowing display of the complete ASCII set. The logic
> circuits are 5V TTL. I will check at home to see if I still have info on
> these useful, but way expensive devices.
>
>
> CIAO - Martin R. Green
> spamBeGoneelimarRemoveMEbigfoot.com
>
> ----------
> From: Jacques Vrey[SMTP:.....jvreyEraseMEIT.NEW.ISCORLTD.CO.ZA]
> Sent: Wednesday, September 10, 1997 4:30 AM
> To: spamPICLISTspam_OUT@spam@mitvma.mit.edu
> Subject: Re: [OT] 7 Segment LED
>
> >
> > Hi,
> >
> > Sorry I don't have a diagram for you, but I have a suggestion.
> >
> > Have you tried putting one of them in a breadboard, and using a 3V supply
> > and a 200R resistor to check out the pins. Connect a random pin to ground
> > then connect each pin in turn through the resistor to +3V.
> >
> > These are the possible outcomes.
> >
> > Common cathode, gnd not connected to cathode - no segments light up.
> Connect
> > +ve through resistor to pin and probe for cathode.
> >
> > Common cathode, gnd connected to cathode - lots of segments light up in
> turn
> > (bingo) start writing down pin allocations.
> >
> > Common anode, gnd connected to anode - no segments light up. Connect +ve
> > through resistor to pin and start writing down segmemnts.
> >
> > Common anode, gnd connected to segment - only one segment lights up.
> Connect
> > +ve to pin which lights segments and start writing down pin allocations.
> >
> > There may be some pins which are not connected, or which are bridged
> > together. If you have a meter in series with the 3V supply it's easy to
> see
> > which ones these are.
> >
> > Hope this is some help,
> >
> > Keith.
> > ------------------------------------------------------------
> > Keith Dowsett "Variables won't; constants aren't."
> >
> > E-mail: spamkdowsett@spam@STOPspamrpms.ac.uk or spamBeGonekdowsettspamBeGone@spam@geocities.com
> >
> > WWW: http://kd.rpms.ac.uk/index.htm
> > www.geocities.com/CapeCanaveral/Lab/8979
> >
> >
> Hi there..again
>
> In response..
> That was the first thing I tried and all I managed to locate was the
> dp's.
> This 7seg has a small chip in it that appears to do some decoding as
> each segment actually consists of four individual LED's as such:
>
> +--\/----\/--+ +------------+
> | | 14|0 0|1
> | o o o o | | |
> | o o | 13|0 0|2
> | o o | | T |
> | o o o o | 12|0 I 0|3
> | o o | | L |
> | o o | | 3 0|4
> |o o o o o o | | 1 |
> | | 10|0 1 0|5
> | +---+ | | |
> | |IC | | | |
> | | | | | |
> | +---+ | 8|0 0|7
> +-----/\-----+ +------------+
>
> Maybe this will shed some light on the problem.
> Thanks anyway.
> Regards
> Jacques Vrey
> Iscor Steel Profile Products
> Newcastle
> South Africa
> Tel: +27 (0)3431 48759
> RemoveMEjvreyRemoveMERemoveMEit.new.iscorltd.co.za
>
>I just designed a circuit for a 12V/6A trolling motor. Do you have
>TinyCAD? If not, I'll send you both TinyCAD and the schematic. I had
>a problem with blowing one leg of the H brdge until I substituted
>MOSFETS. The total price was roughly $20 - $10 of it in heatsinks
>and you can breadboard it first. It uses a 555 time to PWM a 5
>MOSFET bridge. It works fine.
>
>KcW
'S ok. I don't need to handle near that much power. I'm looking for
something that will run a motor that uses 200 milliamps at 24
volts. I'm trying to avoid building a discrete H bridge cuz
SOMEBODY has done this before and put it obn a chip.
>.In the past I have used a SGS-Thompson L293D to drive small DC
>motors at 24VDC with a PIC. It is a 4 channel push-pull driver with
>internal clamping diodes. It is a 16 pin package with the capability
>to provide 2 full bridges (thus driving 2 motors). It is limited to
.>.about 600 ma. and needs around 40 ma. to operate. Its current
>price is $2.53USD from Arrow Electronics.
At $2.53 US each that's $0.63 per H bridge. I don't think I could
build a discrete H bridge much cheaper. And $2.53 is the onesies
price. Looks very interesting. Thanks!
This may not be the fault of his ISP. Many POP3 servers choke on very
large emails, which is why good email programs allow you to automatically
chop big attachments into multiple smaller emails (the infamous [1 of x] on
the newsgroups).
Try sending your stuff broken into smaller chunks next time.
I sent you a huge email with TI datasheets - and they bounced back at
me.... !
Please ask your ISP to get their act together... it hurts getting 1.7Megs
of
returned mail !
-- -- -- -- -- -- -- -- -- -- -- -- -- -- --
--
I have no idea how it works, I just know how to use it.
-- -- -- -- -- -- -- -- -- -- -- -- -- -- --
--
Tjaart van der Walt writes:
>desk. Gasp and run to open all the windows (PCB's are generally not made
>to smell good at high temperatures.)
If you have a smoke alarm in the room, find another place. I set
ours off doing that to a conventional board with a paint stripper gun. A
respirator that keeps the smoke directly out of your face is probably a
good thing to use, also. That vapor can't possibly do any good for one's
lungs and liver.
Martin McCormick WB5AGZ Stillwater, OK 36.7N97.4W
OSU Center for Computing and Information Services Data Communications Group
Peter Norton's book called Inside the IBM P.C. is pretty old these
days, but it has a wealth of that kind of information. You are exactly right
in that the status of the Caps lock key is a bit in a low memory address
that can be set or cleared just like any other memory location. There is a
ROM BIOS routine for toggling this bit as well as bits for Scroll lock and
Numlock keys. There is a computer virus that causes randomization of the
case of tHe letTerS BEIng typed by setting and clearing the Caps lock bit.
When I wrote the speech driver that I use, I read that byte which has
all those lock bits in it and produce a message when one of them changes.
The shift keys do not modify these bits, but produce scan codes that are
just like hitting any other key. The BIOS sees that you have hit the shift
key so it makes an upper case letter if the mode was lower case or vice
versa.
Martin McCormick WB5AGZ Stillwater, OK 36.7N97.4W
OSU Center for Computing and Information Services Data Communications Group
>'S ok. I don't need to handle near that much power. I'm looking for
>something that will run a motor that uses 200 milliamps at 24
>volts. I'm trying to avoid building a discrete H bridge cuz
>SOMEBODY has done this before and put it obn a chip.
If you're getting the 24V from a line-frequency transformer, connect the
motor to the transformer secondary through a triac. Trigger the triac on
positive half-cycles to make the motor go forward, on negative
half-cycles to make it go backward. Saves having to rectify the AC in
the first place. It doesn't get much cheaper than this, should also be
rather durable. The motor only gets half-cycles of power so it should be
one built for a lower voltage if you need rated speed and torque from it.
>
> 'S ok. I don't need to handle near that much power. I'm looking for
> something that will run a motor that uses 200 milliamps at 24
> volts. I'm trying to avoid building a discrete H bridge cuz
> SOMEBODY has done this before and put it obn a chip.
>
> -
> Best Regards,
>
> Lawrence Lile
Circiut Cellar Ink #83 June 1997 Page 74. Jeff Bachiochi uses an LM18293 from
National. There is a circuit diagram as well.
At 08:39 AM 9/11/97 +1000, you wrote:
>>
>> 'S ok. I don't need to handle near that much power. I'm looking for
>> something that will run a motor that uses 200 milliamps at 24
>> volts. I'm trying to avoid building a discrete H bridge cuz
>> SOMEBODY has done this before and put it obn a chip.
>>
>> -
>> Best Regards,
>>
>> Lawrence Lile
>
>Circiut Cellar Ink #83 June 1997 Page 74. Jeff Bachiochi uses an LM18293 from
> National. There is a circuit diagram as well.
>
>Cliff Rogers (Computer Technician) email spam_OUTcliffrogersspamBeGoneusa.net
>Absolute Computers Pty. Ltd. Cairns, Queensland, Australia.
>
I'm in the same situation, only I have just 6 volts to work with. Don't
use the LM18293 in any new design. I just visited their web site and the
part is listed as "lifetime buy", which means to me that they don't make
them any more. In my case, it also wastes too much power. It drops up to
1.8 volts on the high side (at 1 amp), but it since it uses bipolar
transistors, it won't be much less at lower currents. I'm looking at a 3
phase MOSFET brushless motor driver from Fairchild, but it costs more than
I want to pay in production quantities. I can't seen to find a 2 phase
(h-bridge) version. I'm also looking at some HEXFET arrays from
International Rectifier.
If someone knows of a low drop (Rds) MOSFET h-bridge, please let me know.
> Jacques,
>
> Complete data on the TIL311 is available at http://www.ti.com.
>
> cheers,
> -larry-
>
>
Thanks very much, I found the datasheet in pdf there.
Thanks to everyone for the help.
Oddly enough I was looking for exactly this type of display some time
back for a PC POST (Power on self test) Card - not knowing that I
already had some. The project never came off the groung so maybe I'll
pursue it now.
> Correction, when I reread the original post, I realized that I had spouted
> crap, sorry. The TIL311 was a single digit, 7 segment device as you
> stated, but it did in fact have an on-chip BCD to 7seg decoder/latch.
>
> As I said, I will try to find the specs on this for you.
>
> Martin R. Green
> EraseMEelimarRemoveMEbigfoot.com
>
Thanks Martin, but Larry Payne has already helped - see -> http://www.ti.com
-------------------------------------------------
Siegfried Grob
School of Electronic and Electrical Engineering
University of Leeds
Institute of Integrated Information Systems
Woodhouse Lane
Leeds LS2 9JT
At 04:19 PM 9/10/97 +0000, Lawrence Lile wrote:
>'S ok. I don't need to handle near that much power.
Maybe you do... measure the motor resistance and calc the 24V current
through it. I recommend designing for this current as that's what will
happen when you get a locked rotor or if you step from stopped to full
speed. You can go light on the heat sink if your driver can sense an
overload and shut down.
---------------------------------------------------------------------------
Lynn Richardson - Design Eng.|WA0ZNL |Progress Instruments, Inc.
DC - 1GHz, RX, TX 100W, PLL |WA0ZNL.AMPR.ORG |807 NW Commerce Drive
ASM 6805, 8051, Z8, PIC |44.46.176.3 |Lee's Summit, MO 64086
C |@spam@lrichSTOPspamproginst.com|P(816)524-4442 F 246-4556
Lawrence Lile wrote:
>
> I'm looking for a cheap half bridge driver,
<snip>
> What do you PICsters use to drive relays and small DC motors?
Tjaart sez:
>If you have an old MFM hard drive laying around,
What else are MFM's good for except parts anyway?
>you can rip off the
>two L293's (quad half bridges 1A plenty volts each) Else you can get
>the National equivalent the LM18293. It takes 5V inputs and is very
>easy to use.
>I have just discovered a Natnioal device LM18200 I think the number
>is correct. It is a full H bridge 3A to 50V needs logic to drive it
>and it works in parellel with others. I made a 60W sine wave
>inverter from two of these a transformer a PFC chip and 24v DC. it
>is described as a motor driver in a 10 pin packet with tab. It
>contains all the current limit bits bootstrap for the high side and
>overtemp protection. I am planing to generate the PWM pattern with a
>'71 and increase the bus voltage to 48v a three chip soulition to DC
>to AC conversion at just over 100W coludnt be more simple (famous
>last words) worth a little pondering !!!
Looks interesting. When you get the code written for sine wave PWM
I'd like to see it. I've got an old project laying around to make an
inverter.
>If you want real power IXYS makes a 200A 1200V half bridge IGBT
>module with inbuilt drivers needs 15v and 5v logic to drive them or
>Semikron makes a SKHI200 which is a half bridge driver but no IGBT
>or FET but will drive both again needs 15v and logic drive will
>drive multiple parellel IGBT's max 5 (1250A @ 1200V) of course at
>these levels the miller cap is huge and the module is v expensive.
>For more modest power levels we use a SI9910DJ from Siliconex drives
>fets directly and IGBT's when you add a PNP transistor to discharge
>the gate.
>Cheers Steve.....
1250A at 1200 volts....wow! What is it for, Wheeling power between
nuclear power plants?! I guess I don't need anything quite that big.
A 3 watt motor would be fine.
Best Regards,
> I'm looking at a 3 phase MOSFET brushless motor driver
> from Fairchild, but it costs more than I want to pay in production
> quantities. I can't seen to find a 2 phase (h-bridge) version. I'm
> also looking at some HEXFET arrays from International Rectifier.
>
> If someone knows of a low drop (Rds) MOSFET h-bridge, please let me
> know.
>
> Best regards,
>
> Andy Morris
If I find one I'll tell you. At six volts you might get away with
the Telcom TC4426, 4427 or 4428. Don't believe the data sheet where
it says they will withstand 22 volts. If you get a spike anywhere
near 16 volts they MORPH into a CROWBAR. :) But if you are running
on a battery supply they will probably work great.
Best Regards,
>Martin interjected thqat:
> Tjaart van der Walt writes:
> >desk. Gasp and run to open all the windows (PCB's are generally not made
> >to smell good at high temperatures.)
>
> If you have a smoke alarm in the room, find another place.
> I set
> ours off doing that to a conventional board with a paint stripper
> gun. A respirator that keeps the smoke directly out of your face is
> probably a good thing to use, also. That vapor can't possibly do
> any good for one's lungs and liver.
Solder smoke has definitely been linked to occupational asthma. Do
not breathe it if you can help it. Install a little fan on your
bench to keep it out of your face, get one of those air cleaners for
your bench. Whatever you do, don't end up like me, puffing away on
inhalers for the rest of your days.
In a message dated 97-09-10 16:44:12 EDT, you write:
<<
You can build yr own H-bridge out of discrete transistors -- a
little more expensive than an appropriate IC at low power, but it is the
way to go for higher powers. An H-bridge is a really simple circuit --
it's somewhere in the Art of Electronics along with a complete discussion
of analysis and transistor selection. If you can code assembler, you can
certainly build an H-bridge.
Pierce Nichols
>>
Hello Pierce,
In theory the H bridge is simple, but the simplicity stops when you actually
try to build one. Check out the circuit for the LM18245 from National.
It becomes very complicated when you try to use 5 volts to switch anything
greater than 5 volts. If you turn on a Mosfet with 5 volts that is what you
get out of a P channel Mosfet. The 18245 uses a DC/DC converter to step up
the control voltages.
If you are running simple 3 to 6 volt motors then I agree with you. You can
kill alot of transistors trying to get one working though.
An H bridge, if not connected right the first time, will incinerate in a
fraction of a second.
Been there...Done that...
Many ISPs are limiting email message sizes to 1 or 1.44 meg. If you must
email large files an easy way arround the limit is to UUENCODE it and embed
it in the body of the message. You can then span several messages and still
get very large files sent.
At 02:05 AM 9/11/97 +0800, you wrote:
>jvrey...
>
>I sent you a huge email with TI datasheets - and they bounced back at
me.... !
>Please ask your ISP to get their act together... it hurts getting 1.7Megs of
> returned mail !
>
>-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
>I have no idea how it works, I just know how to use it.
>-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
>
>
Larry G. Nelson Sr. RemoveMEL.NelsonRemoveMEieee.org http://www.ultranet.com/~nr
At 03:54 PM 9/11/97 -0400, you wrote:
>Many ISPs are limiting email message sizes to 1 or 1.44 meg. If you must
>email large files an easy way arround the limit is to UUENCODE it and embed
>it in the body of the message. You can then span several messages and still
>get very large files sent.
>
>
>At 02:05 AM 9/11/97 +0800, you wrote:
>>jvrey...
>>
>>I sent you a huge email with TI datasheets - and they bounced back at
>me.... !
>>Please ask your ISP to get their act together... it hurts getting 1.7Megs of
>> returned mail !
>>
>>-- -- -- -- -- -- -- -- -- -- -- -- -- -- --
--
>>I have no idea how it works, I just know how to use it.
>>-- -- -- -- -- -- -- -- -- -- -- -- -- -- --
--
>>
>>
>Larry G. Nelson Sr.
>TakeThisOuTL.Nelson@spam@@spam@ieee.org
>http://www.ultranet.com/~nr
>
>
Don't send files like this to everyone on the piclist, send them only to
the people you want to get them!
---------------------------------------------------------------------------
Lynn Richardson - Design Eng.|WA0ZNL |Progress Instruments, Inc.
DC - 1GHz, RX, TX 100W, PLL |WA0ZNL.AMPR.ORG |807 NW Commerce Drive
ASM 6805, 8051, Z8, PIC |44.46.176.3 |Lee's Summit, MO 64086
C |TakeThisOuTlrichspamproginst.com|P(816)524-4442 F 246-4556
You can use either, but to use WordPad you need to select the "Save as
Ascii Text" option every time you save the file. Notepad automatically
saves as ascii text. To make the screen more readable in Notepad,
select a fixed width font such as Terminal.
Hope this helps.
Eric
______________________________ Reply Separator _________________________________
Subject: [OT] Is Wordpad or Notepad ASCII compatible?
Author: Eric van Es <spamBeGonevanesKILLspamILINK.NIS.ZA> at INTERNET
Date: 9/10/97 10:24 PM
Hi guys
I've always used the dos editor to write my source code in asm
(obvious).
Can I use Win95's Wordpad or Notepad to generate the ASCII file that
MPASM needs?
While just about any wordprocessor or text editor can be used to write code. I
use a freeware program called PFE, programmer's file editor. This program has
alot of useful features.
1. Line numbers can be turned on or off.
2. Command lines can be run from within the editor and the output screens
can be captured.
3. The program allow multiple files to be open in separate windows.
4. The program also has a macro recorder to allow you the automate its
operation.
I use this program to write alot of Zilog code. My Zilog compiler is DOS based
and it is a pain to keep having to drop into DOS to run a compile. By using the
command line feature, I can execute the compiler and capture the results to a
window. The I can view both the compiler output results and the code at the
same time.
At 10:24 PM 9/10/97 +0200, you wrote:
>Hi guys
>
>I've always used the dos editor to write my source code in asm
>(obvious).
>
>Can I use Win95's Wordpad or Notepad to generate the ASCII file that
>MPASM needs?
>
>Thanks...
>
>--
>Eric van Es | Cape Town, South Africa
>EraseMEvanesRemoveME@spam@ilink.nis.za | http://www.nis.za/~vanes
>LOOKING FOR TEMPORARY / HOLIDAY ACCOMODATION?
>http://www.nis.za/~vanes/accom.htm
>
Yes. I do it all the time.
> Many ISPs are limiting email message sizes to 1 or 1.44 meg. If you
> must email large files an easy way arround the limit is to UUENCODE
> it and embed it in the body of the message. You can then span
> several messages and still get very large files sent.
And, if you didn't, zip it first...
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
> Hi guys
>
> I've always used the dos editor to write my source code in asm
> (obvious).
>
> Can I use Win95's Wordpad or Notepad to generate the ASCII file that
> MPASM needs?
WordPad is slow, and tends to write files out in complex formats
unless you keep your eye on it. Notepad is adequate - barely.
I use a shareware (registered!!) program called TextPad, by Helios
Software - its designed for programming, and you can set it up to
default to whatever coding styles you like. (auto indent, tabs, file
extension names, etc) Does good searches too - if you've got a group
of .c and .h files, and want to find (and/or replace) occurrences of
"word" it'll search files in dirs and subdirs.
> If someone knows of a low drop (Rds) MOSFET h-bridge, please let me know.
How about Thomson's L6203:
Supply voltage 48 V max
Current 3 A max
Rds(on) 0.3 ohm typ. (0.55 max)
Inputs TTL compatible
Operating frequency up to 100 kHz
Specified reverse source-drain diode
Short circuit protected
Thermal shutdown
Multiwatt 11 package
Except I don't know if you consider it still cheap. Here in Czech in costs
about $4 in single quantities.
Primary area of application is in driving bipolar stepper motors, but will
certainly suit for DC motors as well. For lower currents see L6202 and L6201.
What do we call ourselves ??????
NETTERS ?
PICLISTERS ?
PIGS ? (Pic Interest Group as in FIG (Forth Interest Group))
I saw a couple of stickers saying things like :
SURFERS DOES IT STANDING UP
TEACHERS DOES IT OVER AND OVER
DIVERS DOES IT UNDERWATER
PROGRAMMERS DOES IT IN BYTES
NETWORK SUPERVISERS DOES IT ON SERVERS
> Lawrence Lile wrote:
>
> > I have seen plotters that use a special pen to directly draw
> > photoetch on bare copper. All it takes is a flatbed plotter, 8-1/2"
> > x 11".
Nic wrote:
> Do you know where to get these pens? Or who makes them?
I asked a friend of mine in China, and he replied (apologies for the
broken English:
The water-resistant pen is buyed from electronic's shop. It have a
"OHP-marker edding 142M" marking.I don't know where you get it in
states. You can buy any water-resistant pens such as PILOT permanent
and make a holder to fit it in your plotter.
Either wordpad or notepad will produce the plain ASCII source that MPASM
needs, but if you are using Win95, why not use MPLAB, which has a "smart"
editor built in?
If you must use an external editor (Multi-Edit is the one I use) and you
want something free, try PFE (Programmer's File Editor), which a lot of
programmer's swear by.
> WordPad is slow, and tends to write files out in complex formats
> unless you keep your eye on it. Notepad is adequate - barely.
> I use a shareware (registered!!) program called TextPad, by Helios
> Software - its designed for programming, and you can set it up to
> default to whatever coding styles you like. (auto indent, tabs, file
> extension names, etc) Does good searches too - if you've got a group
> of .c and .h files, and want to find (and/or replace) occurrences of
> "word" it'll search files in dirs and subdirs.
Why doesn't anyone else seem to use good 'ole emacs? I use it for
programming (mostly C for unix boxes), and it works fine. I know there is
a DOS variant, and there's prob. a windows variant by now (wouldn't know
-- I'm a Linux boy). It's also free.
Hi, I had like to begin with 68HC11 E2 and F1 (or A1) in single and
>extended mode (with EPROM). Can somebody give me so information? Thanks
>a lot.
David
David, Contact Marvin Green at spamBeGonemarvinKILLspamKILLspamagora.rdrop.com. he makes a nice basic
68hc11 board 2.5 in. by 3.5 inch. and Karl Lunt (Nut & Volt's) has the
software SBASIC on the SRS (Seattle Robotics Soc.) Web site.
I have a HP 7221 (7225?) that I have used many times to plot an etch
resist pattern on copper clad board. I took a standard HP plotter pen,
removed everything except the body, then bored it out in a lathe to fit
a permanent ink pen. (You can probably do this by hand reaming with an
appropriate set of drills or careful sanding and filing.) I found that a
Sanford ultra fine point Sharpie worked the best. You need to adjust you
pen speed and width settings to get the best line while still moving
fast enough so that the pen tip does not dry out. Width setting is
important so that you don't overlap what has already been plotted as the
partially dried ink will clog up the pen tip. Likewise, don't let the
pen dry out in the holder between plots. I used drafting tape to hold
the board in place. I successfully did a design once with pads for a
flat pack IC that came out useable.
I also experimented with other brands of pens (and pencils!). I never
was able to get good results with a Berol Fine Point Permanent (which
is, BTW, the "etch resist" pen that GC electronics, Kepro, and Radio
Shack used to sell for more than a whole box of the same pen at a office
supply store). I never could keep the tips from drying out during the
plot. I have also found that for extremely fine line drawings on paper
or vellum (not film), a Pilot Precise roller ball gave excellent
results. Text smaller than 1/16 inch was clearly readable!
Can anyone on the list suggest a software development methodology (ie
Yourdon) suitable for low level embedded software.
Many Thanks
--
Mike Burns
___________________________________________________________
If you dont know where you are going, you can never get lost
------------------------------------------------------------
> Hi
>
> I am looking for a Z80 disassembler .
>
> Ready to swap 8051 good dissasembler for the above.
Yeah? What platform? I've got one for a TRS-80 (if the tape
hasn't faded, which it probably has)
Seriously, why not use a search engine on the web? I got 41 hits on
"z80 Disassembler" with MetaCrawler
Here's some of them...
Query: z80 disassembler
Collated Results: 1 to 20 of 41 references.
Result pages: 1 - 2 - 3 ÊÊnext
1000 z80-300.zip - ZX Spectrum 48/128 emulator, tape & disk supp.
z80-300.zip - ZX Spectrum 48/128 emulator, tape & disk supp. I have
uploaded to SimTel, the Coast to Coast Software Repository (tm),
(available by. http://www.gi.net/MSDOS_A/PM-1994/94-10/94-10-29/0014.html (Lycos)
1000 SIG/M Volume 278 Z80 Disassembler -CATALOG.278 contents of SIG/M
Volume 278 released May 16, 1986 SIG-M .LIB donation form JOIN .ACG
ACGNJ membership application CRC .COM checksum program USQ .COM
unsqueezes squeezed files DELBR .COM to remove files from .LBR http://ftp.barc.org:8080/pub/sigm/vol278/-catalog.278 (Infoseek)
1000 The Simtel.Net MS-DOS Collection, simtelnet/msdos/disasm/ http://oak.oakland.edu/simtel.net/msdos/disasm.html (AltaVista)
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
There's a fairly simple description of it and VHDL code for an FPGA
implementation and also some incomplete, flawed VHDL for a CPLD
implementation.
Cheers,
Bob
At 01:55 PM 9/13/97 -0400, you wrote:
>Sorry if this if OFF TOPIC. Can someone tell me where to get specs for the
>PCI bus
>(on the web) as wish to construct a prototype card.
>
>Thank you in advance.
>
>Francesco Cembrola
>
>
I thought about doing this several years ago and called the manufacturer of
my plotter (Graphtec) and they put me in contact with someone who was doing
that with black India drafting ink. I never tried it. Has anybody elde
tried that? It's cheap and readily available at any drawing supply or
office supply store and can be put in any refillable plotter pen.
>I have a HP 7221 (7225?) that I have used many times to plot an etch
>resist pattern on copper clad board. I took a standard HP plotter pen,
>removed everything except the body, then bored it out in a lathe to fit
>a permanent ink pen. (You can probably do this by hand reaming with an
>appropriate set of drills or careful sanding and filing.) I found that a
>Sanford ultra fine point Sharpie worked the best. You need to adjust you
>pen speed and width settings to get the best line while still moving
>fast enough so that the pen tip does not dry out. Width setting is
>important so that you don't overlap what has already been plotted as the
>partially dried ink will clog up the pen tip. Likewise, don't let the
>pen dry out in the holder between plots. I used drafting tape to hold
>the board in place. I successfully did a design once with pads for a
>flat pack IC that came out useable.
>
>I also experimented with other brands of pens (and pencils!). I never
>was able to get good results with a Berol Fine Point Permanent (which
>is, BTW, the "etch resist" pen that GC electronics, Kepro, and Radio
>Shack used to sell for more than a whole box of the same pen at a office
>supply store). I never could keep the tips from drying out during the
>plot. I have also found that for extremely fine line drawings on paper
>or vellum (not film), a Pilot Precise roller ball gave excellent
>results. Text smaller than 1/16 inch was clearly readable!
>
>
>Frank Richterkessing
>
>EraseMEFRANK.RICHTERKESSINGEraseMEAPPL.GE.COM
>
One of the electronics magazines I read covered this process (using a
modified flatbed plotter to apply resist directly to PCB's) in detail a few
months ago. They compared various types of pens, and showed excellent
photographs of the results with each (which were disappointing for all but
one type). It looked like a really useful technique, if you had access to
an old plotter.
I don't remember which mag it was, but I'll look it up and post the
reference in the next few days. And if some of you beg _really_ nicely, I
might be persuaded to scan the article and email it to anyone who request
it.
BTW, if anyone knows of a good (cheap) source for a used plotter for this
purpose, please reply directly to me.
I thought about doing this several years ago and called the manufacturer of
my plotter (Graphtec) and they put me in contact with someone who was doing
that with black India drafting ink. I never tried it. Has anybody elde
tried that? It's cheap and readily available at any drawing supply or
office supply store and can be put in any refillable plotter pen.
>I have a HP 7221 (7225?) that I have used many times to plot an etch
>resist pattern on copper clad board. I took a standard HP plotter pen,
>removed everything except the body, then bored it out in a lathe to fit
>a permanent ink pen. (You can probably do this by hand reaming with an
>appropriate set of drills or careful sanding and filing.) I found that a
>Sanford ultra fine point Sharpie worked the best. You need to adjust you
>pen speed and width settings to get the best line while still moving
>fast enough so that the pen tip does not dry out. Width setting is
>important so that you don't overlap what has already been plotted as the
>partially dried ink will clog up the pen tip. Likewise, don't let the
>pen dry out in the holder between plots. I used drafting tape to hold
>the board in place. I successfully did a design once with pads for a
>flat pack IC that came out useable.
>
>I also experimented with other brands of pens (and pencils!). I never
>was able to get good results with a Berol Fine Point Permanent (which
>is, BTW, the "etch resist" pen that GC electronics, Kepro, and Radio
>Shack used to sell for more than a whole box of the same pen at a office
>supply store). I never could keep the tips from drying out during the
>plot. I have also found that for extremely fine line drawings on paper
>or vellum (not film), a Pilot Precise roller ball gave excellent
>results. Text smaller than 1/16 inch was clearly readable!
>
>
>Frank Richterkessing
>
>EraseMEFRANK.RICHTERKESSINGspamBeGonespamAPPL.GE.COM
>
On Sat, Sep 13, 1997 at 05:00:08PM -0400, Andrew Russell Morris wrote:
> What does AFAIK mean? Does anybody have a list of the acronyms and
> abbreviations used on the piclist? I know some of them like:
Here is a partial list of what you might see on the PICLIST - IRC
type people will have many more :-)
AFAIK as far as I know
ASAP as soon as possible
BBS bulletin board system
BTW by the way
FAIK for all I know
FAQ frequently asked question, or a collection thereof
FOAF friend of a friend
FTP file transfer protocol
FUBAR f'd up beyond all recognition
FWIW for what it's worth
FYA for your amusement
FYI for your information
<g> grin
<vbg> very big grin
IANAL I am not a lawyer (as a disclaimer)
IMHO in my humble opinion
IMNSHO in my not-so-humble opinion
IMO in my opinion
IRC internet relay chat
LOL laughing out loud
MYOB mind your own business (also a popular accounting package in Oz
)
NHOH never heard of him (or, her)
OBTW oh, by the way
OTT over the top
ROTFL rolling on the floor laughing (sometimes ROFL)
RTFM read the f'ing manual
SASE self addressed stamped envelope
SNAFU situation normal, all f'd up
TANSTAAFL there ain't no such thing as a free lunch
TIA thanks in advance (sometimes aTdHvAaNnKcSe)
TNX thanks (sometimes thx) (tnx 1e6 - thanks a million)
TTFN ta ta for now
WRT with respect to, with regard to
WWW world-wide web
YMMV your mileage may vary
--
Clyde Smith-Stubbs | HI-TECH Software
Email: KILLspamclydehtsoft.com | Phone Fax
WWW: http://www.htsoft.com/ | USA: (408) 490 2885 (408) 490 2885
PGP: finger clydespam_OUTspamhtsoft.com | AUS: +61 7 3354 2411 +61 7 3354 2422
---------------------------------------------------------------------------
ANSI C for the PIC! Now shipping! See http://www.htsoft.com for more info.
On Sat, 13 Sep 1997 17:29:36 -0400 Rick Trostel <RTrostelspam@spam@AOL.COM>
writes:
>I picked up a LAMBDA dual regulated power supply at a yard sale
>today.
>I thought it would be perfect for PIC projects.
>
>On the front there is terminals for V+ , Gnd, V-
>and knobs for adjusting Volts and Current limiting, and a readout for
>both
>sides.
>
>You can turn the voltage up and down on the display but I can't get
>anything
>out of the front terminals.
The DC+/S+ and DC-/S- are the output of each supply (very likely the two
sections are completely isolated from each other). The S terminals are
provided for remote sensing (a technique to compensate for voltage drop
in long wires from the supply to the load). Ordinarily leave them
jumpered. The RP terminal is likely "Remote Program", for setting the
output voltage with an external resistor or network. Since the front
panel control apparently works just use it and leave "RP" open. I don't
know what PO an AT would be (Maybe "Power On" and "Attention?") but you
probably don't need them either.
>Does anyone know how to configure the back to send the juice to the
>front
>terminals?
Maybe "PO" is "Panel Out" connected to the front panel + terminal (either
AT or GND would be the minus terminal then). This could be checked with
an ohmmeter. Measure the voltage at the DC/S terminal pairs, it should
correspond to the meter reading. You could just run wires around from
the back terminals to power your circuit. If you really want to use the
front terminals you may need to take the cover off (hopefully I'm not
insulting your intelligence by suggesting pulling the plug first) and try
to trace the wires from them. There may be jumpers inside that
disconnect the front panel ouptuts for example if the supply is used in a
rack system.
Maybe "PO" is "Panel Out" connected to the front panel + terminal (either
AT or GND would be the minus terminal then).
This one is not the same as one I have but the PO terminal on mine is used
for current shareing when many units are opperated in parellel 'Parellel
Opperation' If you trace it back it should go to the input of an op-amp.
Recently several people were discussing how to use a flatbed plotter to
place etch resist patterns directly on PCB copper. I commented that I'd
seen a good article recently and I'd look it up. Well, here it is:
Electronics World, July 1997
This article discusses several methods for getting a resist pattern onto
the copper, and concludes that the best results are with a converted
plotter. It also discusses various types of inks that have been tried, and
show good colour photos of the results with each.
If anyone can't find the magazine at their local library, or is just plain
too lazy, I have scanned the article into 5 GIF's and 1 JPG (for the colour
photo page), and would be happy to email it to any interested parties. The
scans are 200 DPI and total about 8-900K.
Let me know if you have any special needs, otherwise I'll send them MIME
format, six separate attachments.
Hi guys - sorry to bother ya with a way off topic.
Does anyone of you gents (or ladies) use the Genius Netmouse?
Mine gives me trouble - suddenly the magic button won't work! I've also
had trouble with the Driver in Win95 that won't remember to swap the
browsing directions! As soon as I reboot the setting is cleared again!
At 04:55 PM 9/14/97 -0400, you wrote:
> Does anyone know where I can hunt up some power transistors and/or
>H-bridges capable of handling approx. 150A @ 26 volts?
Your best bet is probably 4-5 FETs ganged in parallel for each leg of the
H. What are you driving?
Andy
==================================================================
Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
Hardware & Software for Industry & R/C Hobbies
"Go fast, turn right, and keep the wet side down!"
==================================================================
Pierce Nichols wrote:
>
> Does anyone know where I can hunt up some power transistors and/or
> H-bridges capable of handling approx. 150A @ 26 volts?
>
> Pierce Nichols
Is it for that surface-to-air gun?
--
Friendly Regards
Tjaart van der Walt @spam@tjaartwasp.co.za
________________________________________________________
| WASP International http://wasp.co.za |
| R&D Engineer : GSM peripheral services development |
|Vehicle tracking | Telemetry systems | GSM data transfer|
|Voice : +27-(0)11-622-8686 | Fax : +27-(0)11-622-8973 |
| WGS-84 : 26010.52'S 28006.19'E |
|________________________________________________________|
On 15 Sep 97 at 0:55, Walter Banks wrote: {Quote hidden}
>
> First what type of barcode are you using?
>
> All barcodes have three things in common.
> 1) Calibration information
> 2) Clocking information
> 3) Data.
>
> Most barcode formats also use the size of
> the space between bars for some purpose.
>
> Many years ago Carl Helmers, Ralph Trueblood and I
> wrote a book on barcode technology. The book was titled
> "Contempory applications of barcode technology" It
> contained some simple barcode reader code. The code
> in the book was all written in Pascal and was designed
> to run on an Apple ][ (Did I say it was a while ago?)
>
> PIC's should not have any trouble reading hand wand
> code.
Indeed. I wrote a decoder in basic on a z80 platform (CPM and a very
early MS Basic interpreter). The easiest way is to sample the
photo-transistor return and store it into array, then got thru it
afterwords. This has the advantage of allowing you to check for
differing bar-code standards. (and the disadvantage that you need a
fair bit of ram, and a start sampling indication)
>
> One assumption that is useful is to remember the
> fastest measured speed of a hand held wand was
> 42in/sec (~1m/sec)
Reminds me of a fun party trick of mine (when I had a barcode
reader), I'd take a 3mm permanent marker and draw barcodes by hand -
then scan them to prove their accuracy. Trick is to remember to draw
them BIG. Fairly easy for 3 of 9. I wouldn't try EAN/UPC though.
Wonder why checkout operators in supermarkets seem to think that
scanning a rejected package faster will make it scan better? This
applies to the EFTPOS magstripe readers too. They give it a fast
swipe - it doesn't work - then swipe it at the speed of sound and
seem surprised when it still doesn't work.
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
At 16:55 14.09.1997 -0400, you wrote:
> Does anyone know where I can hunt up some power transistors and/or
>H-bridges capable of handling approx. 150A @ 26 volts?
>
> Pierce Nichols
>
Hi,
what do you think about some FETs in parallel ? Maybe 2 IRFP064N. N-Channel
MOSFET from IRF. Udss=55V, Rds(on)=0.008, Id=98A. That's one of the FETs
with the lowest Rds(on) available today ! Conduction losses would be about
45W for each FET.
> At 04:55 PM 9/14/97 -0400, you wrote:
> > Does anyone know where I can hunt up some power transistors and/or
> >H-bridges capable of handling approx. 150A @ 26 volts?
>
> Your best bet is probably 4-5 FETs ganged in parallel for each leg of the
> H. What are you driving?
Well, it should be 36 volts, not 26. I'm driving a motor for a
solar-electric boat -- we're planning on using Don Lancaster's magic
sinewaves concept and a three-phase motor to replace the current DC motor.
It's a boat for Solar Splash, and we need to get up to 450A total current
during the sprint.
In a message dated 97-09-14 12:59:51 EDT, you write:
<<
If anyone can't find the magazine at their local library, or is just plain
too lazy, I have scanned the article into 5 GIF's and 1 JPG (for the colour
photo page), and would be happy to email it to any interested parties. The
scans are 200 DPI and total about 8-900K.
Let me know if you have any special needs, otherwise I'll send them MIME
format, six separate attachments.
> On the front there is terminals for V+ , Gnd, V-
> and knobs for adjusting Volts and Current limiting, and a readout for
> both
> sides.
>
> You can turn the voltage up and down on the display but I can't get
> anything
> out of the front terminals.
>
> Does anyone know how to configure the back to send the juice to the
> front
> terminals?
>
> Thanks ------------ Rich
>
Sorry Rich, I don't think you have what you think you have. On quite a
few Lambda supplies, the ground terminal is simply chassis ground - not
a common for V+ and V-. Your power supply is probably a single output
only. Connect a meter across V+ and V- and see if it matches the meter
on the supply - bet it does.
The voltage is rather low for IGBT's so the best answer is to look at FET
bridges. Try Seimens, Semikron, IXYS, Toshiba or IR all offer a range of
large FET's / IGBT's and drivers to interface to logic. With FET's watch the
RDSon as this can be the major power loss at these voltage levels. Is it
possable to increase the DC link voltage and hence decrease the current and
losses ?
Not quite bar code... but I did something similar quite a while
back in 6800 assembly. I had a tape drive (from Exatron, I think). I
used a bar code sort of technique to store data on it. A short time
between transitions was a mark, a long time was a space. I then just put
down standard 8 bit asynchronous data. This was a replacement for the
then standard Bell 202 tones on audio cassette. On playback, there was
some leading mark codes, then the data. The software determined had a
period of time it would use to determine whether the incoming pulse was a
mark or a space. Once the pulse was in the appropriate "bin" and the
appropriate one or zero output, the pulse duration was used to help
determine the tape speed and adjust the transition time between mark and
space.
Someone else has suggested capturing the barcode to RAM, then
figuring it out, instead of trying to do it on the fly. It was pointed
out that this could take a bit of RAM. One way to minimize the amount of
RAM would be to just store the amount of time since the last barcode
edge. These times could then be analyzed after the scan.
> The voltage is rather low for IGBT's so the best answer is to look at FET
> bridges. Try Seimens, Semikron, IXYS, Toshiba or IR all offer a range of
> large FET's / IGBT's and drivers to interface to logic. With FET's watch the
> RDSon as this can be the major power loss at these voltage levels. Is it
> possable to increase the DC link voltage and hence decrease the current and
> losses ?
Well, it's 36, not 26 volts. And no, it can't go higher because
it's for a speed controller for a Solar Splash boat, and the rules limit
us to 36V battery voltage, and 54V peak RMS. No way around it.
The problem gets much simpler now that you've described it completely. You
don't need a high side driver, that makes it much easier. You can either
use a gang of mosfets on the low side with a gang of freewheel diodes on
the high side, or a half bridge, but pinch off the high side so you only
use them as diodes.
Use a switch or contactor if you need reverse. You are racing, you want to
minimize conduction losses in your silicon.
Please explain why you want to make your own speed controller instead of
using something like a Curtis PMC?
If you really want to build your own, use lots of mosfets. Keep your
conduction losses to .75 volts or less.
Don't try to drive a gang of mosfets straight off of a PIC or Basic Stamp,
you need more current to overcome the capacitance and Miller effect in the
mosfets.
> On Mon, 15 Sep 1997, Steve Smith wrote:
>
> > The voltage is rather low for IGBT's so the best answer is to look at FET
> > bridges. Try Seimens, Semikron, IXYS, Toshiba or IR all offer a range of
> > large FET's / IGBT's and drivers to interface to logic. With FET's watch the
> > RDSon as this can be the major power loss at these voltage levels. Is it
> > possable to increase the DC link voltage and hence decrease the current and
> > losses ?
>
> Well, it's 36, not 26 volts. And no, it can't go higher because
> it's for a speed controller for a Solar Splash boat, and the rules limit
> us to 36V battery voltage, and 54V peak RMS. No way around it.
>
> Pierce Nichols
>
> The problem gets much simpler now that you've described it completely. You
> don't need a high side driver, that makes it much easier. You can either
> use a gang of mosfets on the low side with a gang of freewheel diodes on
> the high side, or a half bridge, but pinch off the high side so you only
> use them as diodes.
Ok, thank you. This should help.
> Please explain why you want to make your own speed controller instead of
> using something like a Curtis PMC?
Because there is a concept, called a magic sinewave, that allows
us to get very low distortion power sinewaves (3-phase, too), but it is
new enough not be in any commercial products. We have a DAC PWM DC speed
control now. We think we can build a very good magic sinewave inverter
with these magic sinewaves and get better efficiency and lower motor
weight.
> Don't try to drive a gang of mosfets straight off of a PIC or Basic Stamp,
> you need more current to overcome the capacitance and Miller effect in the
> mosfets.
> Because there is a concept, called a magic sinewave, that allows
> us to get very low distortion power sinewaves (3-phase, too), but it is
> new enough not be in any commercial products. We have a DAC PWM DC speed
> control now. We think we can build a very good magic sinewave inverter
> with these magic sinewaves and get better efficiency and lower motor
> weight.
First a question, do you need DC speed control or an amplitude
controlled sine wave? I think the former, but just in case...
Count on dedicating one PIC for the magic sinewave synthesizer.
Of all the possible bit streams for a given sequence of bits, the
number of unique amplitude controlling low order harmonic distorting
ones is limited. Your alternatives are to 1) live with limited
amplitude control 2) allow more lower order harmonics 3) Increase
the length of the bit stream 4) maybe someone else has a fourth
reason (how about get a Scenix chip then you can have magic software
running on magic hardware).
I would really like to see how much more efficient the "magic"
sine waves are compared to the less ethereally PWM generated ones.
Has anyone done the arithmetic, or perhaps less demanding, has
anyone else even thought about it (or even less demanding does any
one else give a damn)? The number of transitions over a fixed time
interval is lower for the magic sine waves. However, the intermediate
harmonics are higher. Let me quantify: with magic you can exactly cancel
all of the even, and the third, fifth, seventh, and perhaps ninth
harmonics. However, the 11th, 13th, and etc. are relatively large
(please excuse the vagueness). Now with PWM for the same frequency
sine wave there might be a residual 2nd, 3rd harmonic, etc. but the
amplitude doesn't increase until you approach the carrier frequency.
Sinewaves. Oh. AC motors. Forget what I said, then. Three half-bridges.
High-side drivers.
Actually, don't forget what I said about conduction losses. At 36 volts, an
AC system may prove to be less efficient than a plain old DC motor and
Curtis controller. I designed the 1000-amp controller for an entrant in the
1994 SEER competition. At 1000 amps, you go to almost any lengths to reduce
conduction loss, or you burn up and die.
>
>> Please explain why you want to make your own speed controller instead of
>> using something like a Curtis PMC?
>
> Because there is a concept, called a magic sinewave, that allows
>us to get very low distortion power sinewaves (3-phase, too), but it is
>new enough not be in any commercial products. We have a DAC PWM DC speed
>control now. We think we can build a very good magic sinewave inverter
>with these magic sinewaves and get better efficiency and lower motor
>weight.
Scott Dattalo wrote:
>Pierce Nichols wrote:
>
>> Because there is a concept, called a magic sinewave, that allows
>> us to get very low distortion power sinewaves (3-phase, too), but it is
>> new enough not be in any commercial products. We have a DAC PWM DC speed
>> control now. We think we can build a very good magic sinewave inverter
>> with these magic sinewaves and get better efficiency and lower motor
>> weight.
>I would really like to see how much more efficient the "magic"
>sine waves are compared to the less ethereally PWM generated ones.
>Has anyone done the arithmetic, or perhaps less demanding, has
>anyone else even thought about it (or even less demanding does any
>one else give a damn)? The number of transitions over a fixed time
>interval is lower for the magic sine waves. However, the intermediate
>harmonics are higher. Let me quantify: with magic you can exactly cancel
>all of the even, and the third, fifth, seventh, and perhaps ninth
>harmonics. However, the 11th, 13th, and etc. are relatively large
>(please excuse the vagueness). Now with PWM for the same frequency
>sine wave there might be a residual 2nd, 3rd harmonic, etc. but the
>amplitude doesn't increase until you approach the carrier frequency.
The nice thing about magic sinewaves is that the distortion comes in mainly at
the higher harmonics. If you are using them to feed a motor (with it's nice
inductive windings), you are essentially pushing your power right into a very
large low-pass filter. As such, the high-order harmonics aren't much of a
problem.
Take a look at Don Lancaster's pages at http://www.tinaja.com for a lot more
info on magic sinewaves.
- Rick "PIC'ing up the thread" Dickinson
+---------------------------------+---------------------------+
| Enterprise ArchiTechs Company | |
| Lotus Certified Notes | Never underestimate the |
| Appl. Design & Administration | bandwidth of a station- |
|(818)563-1061 spamrtdspamnotesguy.com | wagon full of tape reels. |
| http://www.eArchiTechs.com | |
+---------------------------------+---------------------------+
> On Mon, 15 Sep 1997 05:56:22 -0400 Kahn-Syd <@spam@klassspam_OUTSUN-LINK.COM>
> writes:
> > What Kind of barcode am I decoding - (The easiest to decode ?- sorry
> >;-)
> >well I have already found a 3 of 9 bar code freeware font on the net
> >and
> >that seemed to solve one part - getting the stickers for the books.
> >unless
> >you suggest something otherwise. they have nothing now and I could
> >use
> >anything.
>
>
> Lots of books already have a bar code on the back cover.
> One
> that I just looked at SEEMS to be related to the ISBN number... but
> is not it exactly. Might be nice to use the existing numbering
> system and bar codes, though this would not allow you to keep track
> of individual copies of duplicate sets.
Which is the dilemma between selling multiple quantities of an
identical item, and using the barcode as a asset number. Since ppl
don't need to remember barcodes, why not add an extra, say, 128 bits
at the manufacture stage, starting at 0 for every unique product.
You wouldn't need to store the entire number, hashing it with the
unique product number would do...
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
> > Please explain why you want to make your own speed controller instead of
> > using something like a Curtis PMC?
>
> Because there is a concept, called a magic sinewave, that
> allows
> us to get very low distortion power sinewaves (3-phase, too), but it
> is new enough not be in any commercial products. We have a DAC PWM
> DC speed control now. We think we can build a very good magic
> sinewave inverter with these magic sinewaves and get better
> efficiency and lower motor weight.
Was going to ask if you were going 3 phase. You playing with
frequency a lot too? There MUST be a reason aircraft systems run at
400Hz - one suspects weight is one of the factors, and that would
certainly help anything solar...
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
> Someone else has suggested capturing the barcode to RAM,
> then
> figuring it out, instead of trying to do it on the fly. It was
> pointed out that this could take a bit of RAM. One way to minimize
> the amount of RAM would be to just store the amount of time since
> the last barcode edge. These times could then be analyzed after the
> scan.
Another variation I thought of - use an ISR to store incoming data
into a circular buffer, and decode it in the main program...
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
Why go through the wheel invention all over, if you can buy a bar code
scanner that plugs inline between your keyboard and PC. This scanner
pumps out ASCII on the PC side. If you want to use a PIC to read it,
what
can be easier than ASCII? You can set it up for all the popular bar
codes.
--
Friendly Regards
Tjaart van der Walt .....tjaart.....wasp.co.za
________________________________________________________
| WASP International http://wasp.co.za |
| R&D Engineer : GSM peripheral services development |
|Vehicle tracking | Telemetry systems | GSM data transfer|
|Voice : +27-(0)11-622-8686 | Fax : +27-(0)11-622-8973 |
| WGS-84 : 26010.52'S 28006.19'E |
|________________________________________________________|
> First a question, do you need DC speed control or an amplitude
> controlled sine wave? I think the former, but just in case...
> Count on dedicating one PIC for the magic sinewave synthesizer.
> Of all the possible bit streams for a given sequence of bits, the
> number of unique amplitude controlling low order harmonic distorting
> ones is limited. Your alternatives are to 1) live with limited
> amplitude control 2) allow more lower order harmonics 3) Increase
> the length of the bit stream 4) maybe someone else has a fourth
> reason (how about get a Scenix chip then you can have magic software
> running on magic hardware).
I don't think that amplitude control is really the point of using
magic sinewaves. I didn't even realise that you had any amplitude
control at all. But you do have accurate phase and frequency control
which is important for speed control of AC motors. To implement magic
sinewaves there are only four drive transistor transitions per cycle,
so even if you want 500 Hz you have only 2 kHz switching. Although the
bit sequences that define the magic sinewaves are long it all comes
down to accurately timing the four transitions. That is, you don't
necessarily have to shift 1000-bit sequences to generate magic
sinewaves.
> I would really like to see how much more efficient the "magic"
> sine waves are compared to the less ethereally PWM generated ones.
> Has anyone done the arithmetic, or perhaps less demanding, has
> anyone else even thought about it (or even less demanding does any
> one else give a damn)? The number of transitions over a fixed time
> interval is lower for the magic sine waves. However, the intermediate
> harmonics are higher. Let me quantify: with magic you can exactly cancel
> all of the even, and the third, fifth, seventh, and perhaps ninth
> harmonics. However, the 11th, 13th, and etc. are relatively large
> (please excuse the vagueness). Now with PWM for the same frequency
> sine wave there might be a residual 2nd, 3rd harmonic, etc. but the
> amplitude doesn't increase until you approach the carrier frequency.
I'm haven't bothered to check the claims of harmonic distortion and
compare with PWM. But power efficiency is going to be heaps better
with the magic sinewaves. If the PWM frequency is 10 times the
sinewave frequency then there will be 20 transitions per cycle (cf 4
transitions for magic sinewaves). The motor will filter out the higher
harmonics so having no low-order harmonics may be all you require.
Magic sinewaves require a dual polarity supply which is less
convenient when you are operating from a solar panel.
I like the looks of that chip - it looks to be available locally and is
only 25$ or so in single quantitys. I found a wand at a surplus place and
it is only 25$ or so. I feel that with a basic Stamp and a weekend or two I
could build a wedge for under 100$ and still have bragging rights. The next
step would be interface a LCD Module and a some eeprom for scan storage and
make it portable so we can walk around and scan the books on the shelves
then dump it back to the PC.
> On 16 Sep 97 at 9:24, Pasi T Mustalahti wrote:
>
> <snip>
>
> > (No, I'm not giving the schema out before Xmas :)
>
> Why Xmas?
PTM: I have decided to make this project before Xmas to be a present for
myself. It is a prosessor card to an older ARP -telephone (made by Nihon
Dengyo for Mocoma )to make it work as a handheld 2m HAM phone.
> MikeS
> <mikesmith_oz@nosp*m.relaymail.net>
> (remove the you know what before replying)
>
--------------------------------------------------------------------------
PTM, spampasi.mustalahtiKILLspamutu.fi,RemoveMEptmustaRemoveMEutu.fi,http://www.utu.fi/~ptmusta
Lab.ins. (mikrotuki) ATK-keskus/Mat.Luon.Tdk OH1HEK
Lab.engineer (PC support) Computer Center OI7234
Mail: Turun Yliopisto / Fysla, Vesilinnantie 5, 20014
Pt 02-3336669, FAX 02-3335632 (Pk 02-2387010, NMT 049-555577)
--------------------------------------------------------------------------
> First a question, do you need DC speed control or an amplitude
> controlled sine wave? I think the former, but just in case...
Well, the former is what we have now. We want something better,
which is the latter.
> Count on dedicating one PIC for the magic sinewave synthesizer.
> Of all the possible bit streams for a given sequence of bits, the
> number of unique amplitude controlling low order harmonic distorting
> ones is limited. Your alternatives are to 1) live with limited
> amplitude control 2) allow more lower order harmonics 3) Increase
> the length of the bit stream 4) maybe someone else has a fourth
> reason (how about get a Scenix chip then you can have magic software
> running on magic hardware).
I know it's limited! As for dedicating a PIC, they're cheaper than
power MOSFETs anyhow, so that's certainly not an obstacle. As for limited
amplitude control, I think 256+ amplitudes are quite enough :). We can
live with a certain level of low-order harmonics w/o having a cow -- they
don't need to be tiny fractions of a percent to still get a major
efficiency boost (a large part of that is switching from DC to
three-phase).
> I would really like to see how much more efficient the "magic"
> sine waves are compared to the less ethereally PWM generated ones.
> Has anyone done the arithmetic, or perhaps less demanding, has
> anyone else even thought about it (or even less demanding does any
> one else give a damn)? The number of transitions over a fixed time
> interval is lower for the magic sine waves. However, the intermediate
> harmonics are higher. Let me quantify: with magic you can exactly cancel
> all of the even, and the third, fifth, seventh, and perhaps ninth
> harmonics. However, the 11th, 13th, and etc. are relatively large
> (please excuse the vagueness). Now with PWM for the same frequency
> sine wave there might be a residual 2nd, 3rd harmonic, etc. but the
> amplitude doesn't increase until you approach the carrier frequency.
>
Yes, but you still have a big huge chunk of energy in the carrier
instead of the fundamental. FFTing the magic sinewave indicates that the
harmonics are pushed way up and spread way up, as well as slashing the
total harmonic power.
> Sinewaves. Oh. AC motors. Forget what I said, then. Three half-bridges.
> High-side drivers.
Yup, I do know that much :). The way Mr. Lancaster suggested doing
it (and I agree with after futzing around with it for few hrs last night)
is having each corner of a delta winding connected to a SPDT switch btwn
power and ground.
> Actually, don't forget what I said about conduction losses. At 36 volts, an
> AC system may prove to be less efficient than a plain old DC motor and
> Curtis controller. I designed the 1000-amp controller for an entrant in the
> 1994 SEER competition. At 1000 amps, you go to almost any lengths to reduce
> conduction loss, or you burn up and die.
That remains to be determined -- this is mostly for the endurance,
because in the sprint we just connect that wonderful Lynch motor we have
across 36V and off we go. The real efficiency bear is in the endurance,
where we're only drawing 70-80A @ 24V -- that's where the PWM loses big
time.
On Mon, 15 Sep 1997, William Chops Westfield wrote:
> Is a three phase motor inherently more efficient than a DC motor?
> That would be one reason to go to magic sinewaves.
Absolutely -- the way a DC motor works is by faking AC with the
commutator. Also, three phase motors are lighter (not a trivial concern --
the Lynch motor weighs over 30 lbs -- more than the bare hull, in fact :).
The speed control makes another 5 lbs.
>
> I think you're only generateing "one" sinewave at a time - the other
> two phases just pick off the sequence from a different offset, right?
Bingo! And you make yr bit-length a multiple of 8, so all your
counters are at the same bit position in different bytes (makes yr code a
little less hairy).
> Was going to ask if you were going 3 phase. You playing with
> frequency a lot too? There MUST be a reason aircraft systems run at
> 400Hz - one suspects weight is one of the factors, and that would
> certainly help anything solar...
Yup, 3-phase is the idea. And I hadn't thought about messing /w
the frequency, but we may do that. It may depend heavily on what we can
scrounge up.
Pierce
"I have a work order for the immediate demolition of your reality tunnel."
> Which is the dilemma between selling multiple quantities of an
> identical item, and using the bar-code as a asset number. Since ppl
> don't need to remember barcodes, why not add an extra, say, 128 bits
> at the manufacture stage, starting at 0 for every unique product.
> You wouldn't need to store the entire number, hashing it with the
> unique product number would do...
UPC effectively is what you just suggested. UPC is a quite a secure
bar-code method (Very difficult to get a wrong valid answer) It is a
well thought out industry driven standard. A lot of thought was put
into the kind of things that would be sold vs. the kind of things
that would be inventoried.
Library books are typical of one type
of inventory with multiple copies that each has to be handled
separately. Mr. Jones has a copy of the book that is overdue but
Mr. Smith is not overdue until next week. And the book's author
is Doe, J. W. and library has three copies two are currently out
the third is on the second floor. This problem has often been
solved in libraries using CODE39 with a unique number on each
book. Since CODE39 is a character oriented bar-code a inventory
number is machine generated which includes a check digit often
either a checksum or credit card type modulus. Libraries solve
the multiple use (whose got and what is it) is solved in a
very library fashion of many different cross indexes on the
inventory data base.
I2of5 is generally used as an inventory control where we
control what is in the inventory and we may three of an item
and we cannot tell the difference and don't care. Each item
type has a different number. The system has a master index.
An example is an automotive plant parts index. If you live
in North America the stickers on a new car are Iof5.
UPC is another inventory control type code that has a the
problem of being printed by many different printers and
on products that don't really like to be bar-coded. To
name three of the common problems, pop bottles where you
have white on black when the bottle is full and white on
clear when it is empty (or upside down). This code was
designed to be read with bars of both lighter or darker
contrast in the same context. It was designed to be read
in both directions with equal ease. The two remaining
problems are the ice-cream container very cold on a hot
day covered with frost and the un-frozen frozen vegetables.
UPC is an inventory control system where the supplier is
important and local product inventory pricing is important.
The supplier and general product area can be identified from
the code on a product. This information is useful in tracking
down information on a uninventoried product. There is enough
information to maintain a local inventory. UPC is compact
with good checking capability and easy to read in very bad
conditions. UPC is an industry controlled standard.
> I don't think that amplitude control is really the point of using
> magic sinewaves. I didn't even realise that you had any amplitude
> control at all. But you do have accurate phase and frequency control
You get amplitude control by switching btwn different sequences --
you pack a few hundred into a PIC, and shove them out on command.
> which is important for speed control of AC motors. To implement magic
> sinewaves there are only four drive transistor transitions per cycle,
> so even if you want 500 Hz you have only 2 kHz switching. Although the
> bit sequences that define the magic sinewaves are long it all comes
> down to accurately timing the four transitions. That is, you don't
> necessarily have to shift 1000-bit sequences to generate magic
> sinewaves.
Not quite -- you have more than 4 transitions, by quite a bit. You
usually have a dozen or so tranistions (which is still a small fraction of
an equivalent PWM scheme) per cycle, and your fundamental soaks up most
of the energy, followed by some very high harmonics (which don't actually
take that much). As you mentioned, phase and frequency control are trivial
with magic sinewaves.
> Magic sinewaves require a dual polarity supply which is less
> convenient when you are operating from a solar panel.
Turns out that with a delta-wound three-phase motor, you can use
magic sinewaves with a single polarity supply (because you can still get
current to go either way in any winding by simply switching its ends).
> Was going to ask if you were going 3 phase. You playing with
> frequency a lot too? There MUST be a reason aircraft systems run at
> 400Hz - one suspects weight is one of the factors, and that would
> certainly help anything solar...
Yes, weight is a big reason, the transformers needed for 400hz are much
lighter and smaller for the same rating 60 hz transformer. I believe this
is the biggest reason, wreaks havoc on anything audio on a plane, blocking
60hz isn't that bad, blocking 400 hz, well just takes away some of the more
common notes! TTYL
> On Tue, 16 Sep 1997, Mike Smith wrote:
>
> > Was going to ask if you were going 3 phase. You playing with
> > frequency a lot too? There MUST be a reason aircraft systems run at
> > 400Hz - one suspects weight is one of the factors, and that would
> > certainly help anything solar...
>
> Yup, 3-phase is the idea. And I hadn't thought about messing
> /w
> the frequency, but we may do that. It may depend heavily on what we
> can scrounge up.
Ex air force electric motors would be available at a lot of surplus
stores...
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
In a message dated 97-09-16 07:08:35 EDT, you write:
<<
I like the looks of that chip - it looks to be available locally and is
only 25$ or so in single quantitys. I found a wand at a surplus place and
it is only 25$ or so. I feel that with a basic Stamp and a weekend or two I
could build a wedge for under 100$ and still have bragging rights. The next
step would be interface a LCD Module and a some eeprom for scan storage and
make it portable so we can walk around and scan the books on the shelves
then dump it back to the PC. >>
Last I checked, comercial taiwanese units were about $100!
The one I saw came with the wand and an interface to the PC keyboard.
> Sounds like you are one of those rare souls with a very short
> retinal persistence. I find no noticeable flicker, or "strobe", on
> any LED displays where all characters are scanned on less than
> 1/30th of a second.
> You are a prime example of doing "worst case" design, and going for
> a
> 1/40th or 1/50th of a second full scan.
Supermaket ones drive me crazy.
>
> I have heard of people that get headaches watching commercial movies
> because the 1/24th of a second frame rate flickers dramatically to
> them.
Um, maybe, I don't go often. I recall sitting thru the entire
StarWars trilogy (when it was first released) - it wasn't my head
that ached - bit lower.
What scan rate do you run your monitor at? (vertical) - Mine's going
nicely at 85 - thats nice to look at straight on.
MikeS
<mikesmith_oz@nosp*m.relaymail.net>
(remove the you know what before replying)
I'm trying to use a PIC to drive a standard, run-of-the-mill, LCD display,
and am having trouble understanding the operation of the "busy flag". The
model is an Optrex DMC-20481 (or something like that) with an
industry-standard Hitachi HD44780 controller. Some important bits were
lost in the manual's translation from Japanese, so I'm left a little
confused. After sending a command or data byte to the LCD I think you can
do 1 of 2 things before sending the next:
1. Wait a worst-case period of time before sending the next byte (not a
problem).
2. Read the "busy" flag before sending the next byte (problem).
For efficiency I'm trying to wait for the busy signal as described in the
databook but it's not working as expected. Seems like the LCD is forever
busy.
First of all, this busy signal is intended for use as I've described above,
yes? (or is it a busy signal for the 4-bit interface mode only?) Next,
when reading a byte from the LCD the PIC is still in control of the
"enable" signal, correct? (i.e. it's not driven by the LCD). Here's my
psuedo-code sequence for waiting for the LCD:
1. Set TRIS register for LCD connection to input, control lines output.
2. Set the "data/command" line to low to indicate a command
3. Set the "read/write" to high to indicate a read
4. Set "data ready" high, wait a NOP (16MHz clock) for the LCD to spit out
the byte
5. Read in the LCD data byte to W
6. Pull the "data ready" signal low again
7. AND W with 0x80 (busy flag is bit 7)
8. If zero, it's not busy and we can continue, otherwise wait and read busy
flag again.
But this seems to hang and think the LCD is forever busy. Ideas?
I'm trying to use a PIC to drive a standard, run-of-the-mill, LCD display,
and am having trouble understanding the operation of the "busy flag". The
model is an Optrex DMC-20481 (or something like that) with an
industry-standard Hitachi HD44780 controller. Some important bits were
lost in the manual's translation from Japanese, so I'm left a little
confused. After sending a command or data byte to the LCD I think you can
do 1 of 2 things before sending the next:
1. Wait a worst-case period of time before sending the next byte (not a
problem).
2. Read the "busy" flag before sending the next byte (problem).
For efficiency I'm trying to wait for the busy signal as described in the
databook but it's not working as expected. Seems like the LCD is forever
busy.
First of all, this busy signal is intended for use as I've described above,
yes? (or is it a busy signal for the 4-bit interface mode only?) Next,
when reading a byte from the LCD the PIC is still in control of the
"enable" signal, correct? (i.e. it's not driven by the LCD). Here's my
psuedo-code sequence for waiting for the LCD:
1. Set TRIS register for LCD connection to input, control lines output.
2. Set the "data/command" line to low to indicate a command
3. Set the "read/write" to high to indicate a read
4. Set "data ready" high, wait a NOP (16MHz clock) for the LCD to spit out
the byte
5. Read in the LCD data byte to W
6. Pull the "data ready" signal low again
7. AND W with 0x80 (busy flag is bit 7)
8. If zero, it's not busy and we can continue, otherwise wait and read busy
flag again.
But this seems to hang and think the LCD is forever busy. Ideas?
hit.fi
