Re: A89: matrix


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Re: A89: matrix




 > That's awesome!  But I think I found one error that (hehe) everyone can
 > assume is a typo, right?
 > 
 > >   dbra    d1,loop                ; Do the loop if needed

Yup.
 
 > On a side note: why not use the register a7?

Well, if you are in userland, you can, of course. If you are in
supervisor mode, however, any interrupt will then take the system in
its knees. If you can disable them and you don't use IRQ7 and you are
absolutely sure that the copy won't end up in a bus error, then you
can use it in sup.vis. mode too.

Most of the time my code is on the supervisor side, so I generally 
assume that messing with a7 is a Bad Thing (unless, of course, it's
context switch time).

Regards,

Zoltan



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