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Old 27 April 2019, 10:15   #163
PeterJ
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Join Date: Feb 2015
Location: Copehagen
Posts: 36
Quote:
Originally Posted by ross View Post
For
lsr #8
the trick is similar:

Code:
    d0.w=xx00
    moveq   #0,d1
    ....

    move.w  d0,-(sp)
    move.b  (sp)+,d1
    ....
    
    d1.w=00xx
In this case you can use stack (so no spare A register and mem) but you need a D register and you must never touch his upper bits.

i just tried with $ff56 and the result was $ff

is it not only if you use movem.w that it clear or set the upper word depending of bit15?

Last edited by PeterJ; 27 April 2019 at 10:30. Reason: edit just add some stuf
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