I'm continuing to try to find the cause of this. It appears the original
cause was a collision between the stack and the heap. I now write a known
pattern between the stack and heap at startup and look at it after the
system has been running for several hours to make sure the known pattern
is still there. It looks like I'm not now getting the stack/heap
collision.

But, about midnight local time last night, I got a half dozen bus error
exceptions, all at the same program address (0x9d031a38). Scanning up from
there in the code view of memory, I see several jr ra instructions above
with no labels before, so I assume this code is generated by the compiler
and not from some library that I have source for (I think there'd be
labels if this was compiled from source during my recent compile). So,
it's difficult to determine what the function of the offending code is.

Looking at the specific address that's generating the exception, the
instruction is beq zero, zero, 0x1d031b1c. I assume 0x1d031b1c is the
destination address of the branch (not the offset to the destination
address). If so, this would be a relatively short branch, which would be
within the branch range.

I have a global called ProcessNum that I update in my main loop before
going off to handle different tasks. I write the value of ProcessNum along
with the exception info to a uart when I get an exception. The general
exception is consistently happening in StackApplications(). I've added
more ProcessNum assignments within StackApplications() to try to determine
which one is causing the problem. I'm also running WireShark to see what
network activity happens around the time of the exception.

Any other ideas as to what to try?

THANKS!

Harold


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