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[Cymric]

No, it's not a divide by zero error. If memory serves me, that is 80000005. The 80000003 is the dreaded 'unaligned address' Guru, indicating on the 68010- that a program has tried to access a program instruction at an odd address (Bad) and on the 68020+ that the stack was pointing at an odd address (VERY Bad). I do not know anything about support of the various OSes on the A2000 (so check with other Guru's ;-)) but here are a few possible causes:

- a defective SIMM
- an unpatched ramlib.handler (can be alleviated with SetPatch, IIRC)
- a too small a stack (can be alleviated with a 'stack' command prior to running a program)
- a very buggy program

Good luck in hunting down the cause!

[Cymric]

Piru wrote:
Not quite. On 68000 and 68010 this is caused by using WORD or LONG access on odd address or by jumping to odd address or by odd supervisor stackpointer on exception.
On 68020+ this is only caused by instruction prefetch attempt from odd address (jump/branch to odd address) or by odd supervisor stackpointer during exception.

Thanks for the input, it's been a while. I must admit you mention things I cannot seem to remember, though. I was always told that the 68020 was indifferent to odd addresses and just used another memory access if it encountered one, save for odd stackpointers, be them user or supervisor. (In other words, SP must be even at all times, (SP) can be arbitrary.) But like I said, it's been a while.