Doug Manzer wrote:
>
> I have an idea for a PIC evaluation board similar to Motorola's
> HC11 board, but perhaps someone has already thought of it.
>
> The PIC would be set up to execute code in external memory, into
> which the user's program could be downloaded. This would only be
> possible for the 17Cxx because only the 16-bit core products
> support code off-chip.
>
> The board would have a "host" serial port for connecting to
> a development host such as an IBM-PC. The PIC would be
> preprogrammed with a small monitor program for downloading,
> debugging, etc. Breakpoints could be supported by gating
> a latch with the address bus -- a match would cause a
> reset or an interrupt, etc.
>
> A 2nd, "user" serial port would allow general communications. All
> the remaining i/o ports would be brought out to pin headers and
> possibly a prototyping area.
>
> If such a thing is already available, could someone tell me where
> and from whom?
>
> BTW a neat trick would be to extend the on-chip RAM by providing
> for writing to data tables in the code area (ie. a form of self-
> modifying code). For instance a C constant array compiles to the
> form
>
>    ADDWF PC,OFFSET
>    RETLW DATA_0
>    RETLW DATA_1
>    RETLW DATA_2 ; etc.
>
> where OFFSET is the array index.
>
> With this code running in RAM and special hardware logic to write
> to it, the processor could change DATA_0, etc. on the fly.
>
> Regards, D.M.
There is a board available from farsoft Computers and the guy's name is
Robert Farrer. Unfortunately he's not on the net but running his own
BBS. He is in the process of getting on thou.

He can be reached at his Fax/Phone line on:

++2711 828 9255

BBS: ++2711 828 6731

or I'll forward any mail to him via local Fax.

Jattie van der Linde