gnupic: Re: [gnupic] more on first picprog attempt
Subject:
Re: [gnupic] more on first picprog attempt
From:
"George M. Gallant, Jr." ####@####.####
Date:
19 Jun 2006 19:45:07 +0100
Message-Id: <1150742695.18533.77.camel@scuba.home.net>
I would like to second Rob's opinion. I built a programmer based on a
PIC18F1320
that connects to the PC via a serial cable. All burn operations are
performed at the
remote end. PC issues commands like erase, burn, read, and transfers 16
byte
packets to the programmer. 20 some pic projects later and I have never
regretted
the time it took to get a solid programmer.
Take a look at the wisp628 for a kit or finished package.
On the downside:
1. I am working on the third generation now. Current system will burn
3.3V targets but the
read back isn't reliable. I suspect the problem is with the
protection resistor in series
with the data. (Probably true on most programmers designed to burn
5 volt parts.)
2. Adding a new device and/or burn algorithm takes work.
3. You need to beg/borrow/steal a burner to boot the first unit.
On the upside:
1. Other people watch by "compile and burn" cycle and want it for
their system.
2. When my original commercial programmer company went I of business I
continued.
3. Increased my fundamental knowledge of the target CPU's
George
On Mon, 2006-06-19 at 18:40 +0100, Robert Pearce wrote:
> On Mon, 19 Jun 2006, Jan Wagemakers ####@####.#### wrote :
> >
> >Interesting. Can you point me to a properly designed JDM-style programmer
> >that works with my low-voltage (5.6V) laptop serial port.
>
> If by "JDM style" you mean plugs into serial port and doesn't use an
> external power feed then no - it simply isn't possible to do the job
> right if you're trying to cheat like that.
>
> As I said, I gave up on all the bad designs out there and did my own.
> It's a parallel port one and uses a 12V power block (non-regulated),
> readily available from Radio Shack or Maplin. Because I tend to do
> things properly (as someone said, I sound like a hardware designer) my
> circuit gives me three different Vdd levels so I can properly comply
> with Microchip's ICSP specification. I'd offer to put the schematic (and
> the driver code I wrote) on my web site, but we're trying to get someone
> up and running and the "throw away what you've got and start again with
> mine" answer isn't very helpful.
