I understand why the situation gets flaged. What I want to know is if the sim allows you to break point when it happens. I guess if the message had more info in it i.e. pc value or register file address it would be easier to find. I did find my error, it was an index into an array getting overwritten. The array was used inside an ISR but filled outside of the ISR. I eventually had to do a trace around where it was happening and search the trace dump to find the error. It sure would have been easier if the sim could have given more help. BTW I don't like to initalize all of memory when using the sim since I want it to find these conditions. I do initalize all of the locations that I use. Maybe we should ask microchip to add more info to the warning messages ie pc value and register file address if appropriate. What do others think? >> Unfortunately, MPSIM will show all your registers as having "00" (except for >> Registers which are initialized on Power Up), so it makes it hard to find. >> In reality, RAM Registers actually power up to some non-zero value. > >When trying to debug stuff using "real" chips, I'll write code to ensure >that all the registers are initialized to zero via loop but generally I'll >try to avoid relying on that: for testing I'll make my init-loop initialize >the memory with other junk to ensure the system 'still' works. > >