Re: A89: How does a 68000 program get into supervisor mode ?


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Re: A89: How does a 68000 program get into supervisor mode ?




>How would I be able to switch into supervisor mode on a 68000 for a program 
>that needs it ?

This is quite simple, I think: Have a look at, for example gray4lib!

   move.w   #$0700,d0
   trap     #1

This will set the highest interrupt mask, which will in fact disable all 
interrupts. What it does is writing #$07 to the system byte. So now, by 
using this you get the TI-89 in supervisor mode:

   move.w   #$2700,d0
   trap     #1

Now, you have access to some more instructions! If it doesn't work, mail me 
at

mike_emk@hotmail.com

I haven't got my computer at home right now, it's getting serviced because I 
had some minor hardware problems. However when I get it back I'll have a 
look at one of my progs which uses supervisor mode (just experimented with 
it...) because I'm not exactly sure if I used #$2700 or anything else

See ya,

Michael Kristiansen
mike_emk@hotmail.com


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