[A89] Re: Traps...


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[A89] Re: Traps...




>I hate it when I mess up by one bit place! I even checked it out with
VTI... Now
>I'll have to see what the T stands for in the debug screen of vti... it must
>group together more flags than trace...

There are 2 bits associated with trace: bits 15 and 14. They designate
different trace modes. The 68000 only supports one configuration: bit15=1,
bit14=0, this means "trace on every instruction." I think the 68020 and
higher have more robust trace options.

I'm not familiar with VTI, so I don't exactly know what you're talking
about, but it could be that the T flag you speak of encompasses the 2 trace
bits.


>VTI apparently does NOT emulate trace exceptions... my code works on my calc,
>but not on vti...

Emulating trace exceptions is simple, but it's a real hassle and most
emulators choose not to implement it... usually for performance reasons.


Bart




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