Xiaofan Chen wrote:
> So in theory all those programmers supporting normal 8-word 18F chips
> should be able to program the 18F USB parts, right?

Not necessarily.  The newer chips don't support multiple panel simultaneous
writes, although to be fair most programmers didn't make use of this awkward
feature in the old chips.  I guess it's possible that programming code that
writes to program memory of the old chips still works on the new ones even
though it's not optimal.  But there are other difference.  Certainly the
programming software must be aware of the new chip IDs, the size of program
memory and data EEPROM, and which config bits are valid.  The bulk erase
configurations are also different as shown in table 3-1 of the programming
specs.

I remember that these chips took some work to implement in the EasyProg and
ProProg.  I had to add new commands to the programming protocol and create
new write algorithms, plus a much more complicated host routine to deal with
the variable write buffer sizes properly.  Maybe things would have largely
worked with the old algorithm, although I never tried it because I wanted my
implementations to be reasonable efficient.


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