Bryan Mumford wrote:
>
> We've been selling a product based on a 16C57 for a couple of years.
> Suddenly the same code fails to run properly. But it's more weird than
> that. The old code, when burned into an eraseable device works fine, but
> not in the OTP parts.
>
> Did I hear than Microchip had changed the die on these parts a few months ago?
>
> We're using the PIC to output address data to a 27C010 Eprom. The addresses
> get clocked out okay on ports RB and RC, but all output bits on RA seem to
> get set to zero at the very end of the sequence in OTP parts, but NOT in
> eraseable parts. In debugging, I've explicity set RA.2 to 1, but it goes to
> zero anyway as if the code were shutting down before it finished the loop.
>
> Any ideas?????
>
> Bryan Mumford
> Santa Barbara, California

Read Answer #1 on 'Fast Forward Engineering - The Answers Page' at:
http://www.geocities.com/SiliconValley/2499/answers.html
This may solve the riddle.

The most Frequently Asked Questions about PICs are on this one page.
Do what I did. Print it out, staple it together, then check it on a
regular basis when you get stuck for an answer.

Andy Warren just makes it all too easy. :-)

Don McKenzie donmck@labyrinth.net.au
DonTronics Tullamarine, Australia
http://www.labyrinth.net.au/~donmck

SLI, the serial LCD that auto detects baud rates from 30 to 125K bps.
SimmStick(tm) A PIC proto PCB the size of a 30 pin Simm Memory Module.
EASY PIC'n Beginners Guide to using PIC 16/17 MicroChip products.