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CPU model for efi332



Michael Collins wrote:
> 
>   I changed the flags to -mcpu32 (which my gas does grok), and
> the generated code is indeed different, without bftst instructions.
> The code now runs further, but still gets an illegal instruction
> exception.  This one I don't get.  objdump -d displays the following
> at what I'm reasonably certain is the fault address:
> 
>     2738:       4afa 60fe       tas %pc@(8838 <.eb+0xa>)
> 
>   This address appears to be in the Spurious_Isr function.
> 

This is the `halt' (0x4afa) instruction which is not decoded correctly
by objdump.

I am not sure if the `MC68331' has a BDM module but if it does and you
enable it you will halt at this point.

I suspect things are failing correctly :). It sort of looks like you are
getting a spurious interrupt.

The `tas' decode is a trap I have fallen into a few times.

-- 
 Chris Johns, mailto:ccj at acm.org