Denial

Is there an easy way to get VICE to enter the monitor on BRK?

Something in my code is causing a RESET and AFAIK I don't have any BRKs...

I suppose you mean a BASIC warm start, as if STOP/RESTORE had been pressed, with the single "READY." prompt in the top-left corner. You could install a custom BRK handler in your code and have that handler produce a register and stack dump:

http://sleepingelephant.com/ipw-web/bul ... php?t=4509

That being said, a common cause of this is a wild pointer address, which does shots into your program code. Up to the point, that the CPU executes some undocumented instructions, and then ends up at a "BRK" that's really the immediate field of a LDA #$00 instruction, or the like.

Thanks Mike!

Yes, that's it exactly - it must be jumping to a random place..

That link looks exactly the ticket...

you could also place a breakpoint on the address of the kernal brk handler...or even the vector