[rescue] SPARCstation 1 boot woes

[David McMackins II]

Excellent information! Well, it turns out that the memory at %pc is all
zeroes! So it seems something is going wrong with the loading of the
boot program, even though it seems to be counting it correctly.

The memory diagnostics are passing, so I don't suspect a memory error.
Any idea what could cause this behavior?

-- 
Regards,

David E. McMackins II
www.mcmackins.org

On Sun, 2025-11-02 at 01:42 +1100, Ethan Hawke via rescue wrote:
> > Upon further consideration of the symptom, a power supply issue
> > also
> > seems unlikely because the boot firmware recovers cleanly from the
> > malfunction and returns to the "ok" prompt. I would expect a power-
> > related malfunction to send it off into executing nonsense and
> > crashing
> > or just resetting the system.
> > 
> > Any other ideas?
> OpenBoot has a very powerful debugger built-in, you can use that to
> try 
> and find
> the faulting instruction, after the trap is raised use '%pc dis' to 
> disassemble the
> bootloader, it will print the faulting instruction and the memory 
> address it was
> running at, if it's an illegal instruction it will likely read
> 'unimp', 
> but you can then
> cross-reference the address with boot.net program to determine if
> it's 
> actually an
> unimplemented instruction or something else such as memory
> corruption.
> 
> You can also use '%pc 100 dump' to view the memory directly.
> 
> Good luck,
> Ethan
> 
> 
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