Jim Durand <durandj@gte.net> wrote:

> I'm suffering from stack overflows on a 17c42 .... BUT, I've done
> a thorough analysis of my software and there is no way I should be
> overflowing the 16 word stack.

    Nevertheless, Jim, you ARE overflowing it... So your analysis
    must not have been thorough ENOUGH.

> As I understand the spec sheet, an interrupt and a call each use one
> word of the 16 word stack.

    Correct.

> There isn't anything else that affects the stack is there?

    No.

> Also a "pending" interrupt (one asserted while interrupts are
> disabled) does not use any stack - the corresponding interrupt
> request bit is merely set - correct?

    Correct.

> I've tallied the max stack usage of all my routines and I should
> be using at most 10 slots. ....  I think I'm missing something. Any
> thoughts?

    Well... Obviously, your software isn't doing what you intend.

    Do you perform any direct writes to the Program Counter?
    Perhaps there's a bug in one of them and you're accidentally
    pointing the PC at a subroutine call.

    Do you have an emulator?  If so, I can suggest some debugging
    techniques that should help you isolate the problem pretty
    quickly... Let me know.

    -Andy

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