Hi Tim,

I designed an 18 Pin PIC programmer that works exactly what you're talking
about here (I call it "YAP" for "Yet Another Programmer).  I use a 16C61 to
interpret the data coming in and program the device.  I also put in a 19 pin
0.100" connector strip so that the device being programmed could be left in
the programmer's socket and executed (via the terminal emulator/16C61's
control).  There is also serial rx/tx pins so messages can be sent to the
terminal emulator.

If you look up the programming specs for the PICs, you will see that a 10
msec delay is required for the data to be loaded into the device.  This
means that the .obj download can only be done very slowly (I used 1200 bps)
to put it directly into the PIC without buffering the data.  (4 bytes to
each instruction at 1200 bps takes 33.3 msec, it could be done at 2400 bps,
but I felt 1200 was more "Standard").

It works quite well and with the 19 pin header, it's actaully pretty good to
prototype with (I put in a programmable clock from executing, 1, 2, 4 or 8
MHz) - Although I prefer writing my code in MPLAB, and using a ZIF socket in
the prototype circuit.

The design will be published in my book (I have it on very good authority
that it will be available the first week of September).  I have no plans to
have it marketted because there are so many *other* programmers out there
(which is why I named it the "YAP").

myke
>Hi
>I have had a great idea (I think!) for a PIC programmer.  I have recently
>posted about programmers for the psion and acorn without much success but
>this might change things.  The one thing most computers, PDAs etc have (or
>is available as shareware) is a terminal program.  If a simple set of
>commands were developed where the hex file was merely sent (either as text
>or a xmodem protocol or something) after a few configuration details to the
>programmer then it could work with almost anything without having to make
>specialist software.  This would probally need a decent PIC to implement a
>file transfer protocol and store the hex file but I think it could be done
>if someone has the time to do it (not me at present - it's school exam
>season!).  What do you think?
>
>
>Tim
>
>p.s.  A further development could be a programmer with assembler built in!
>
>
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"My ancestors didn't spend millions of years clawing their way to the top of
the food chain, just so I could become a vegetarian"