digitalDNA

COP  - related questions

Discussion created by digitalDNA on Apr 28, 2006
Latest reply on Dec 15, 2007 by Joe Puhich
Hello,

I have two questions regarding the COP:

1. I'll quote something from the COP Tutorial then I'll write my question:

"COPCTL (COP Control Register) is located at address $FFFF and overlaps with the CPU Reset Vector.
Writing ANY value to address $FFFF clears the COP counter and the SIM counter. This prevents a COP reset and starts a new timeout period"

So my question is: How to write a new RESET ADDRESS ? Is this possible during program execution if the program is supposed to change the Reset Address according to some environment changes ?



2. System Protection Methods:

It's suggested not to refresh the COP from within ISRs (Interrupt Service Routines). What if execution time of an ISR is undetermined, or lasts longer than the COP timeout period ?


Best Regards,
Roger Tannous.

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