15 Dec 97, zhuxh@cheerful.com writes to All:

 z> I am woundering if the code protection with PIC's is as secure as
 z> promised by Microchip?

Yes, due to Microchip promise only, that code protection exists, and nothing
about actual strength of code protection.

 z> as far as I know, there is a company in Beijin that offers service to
 z> help decode the Microchip's PICs. The cost is about US$1000 for each
 z> chip!

The same service you can also found in Moskow, Russia. They promise any
protected PIC code reverse engineering with cost lower, than $1000
(same price!) in one-two days. For PIC16C84 it can be done for almost free and
for PIC16F8x price is lower, than $100. Probably, both companies use some
technological backdoors in Microchip products. Sorry, I don't know any
technical details, only see advertisiments and know some cases of the
successfull using of this service.

 z> I am afriad my own coding with PICs will be copied by others one day.
 z> Do you have any idea on this? Is my worry unnecessary?

The only things, that can protect you - change you product as frequently, as
possible, add new features, new ideas and didn't try to obtain superprofit.
If you need really protected product for security applications - use special
security designed chips, not wide available microcontrollers.

Alexey

--- GoldED/2 2.50+