Re : A92: learning assembly - real simple question
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Re : A92: learning assembly - real simple question
Dans un courrier daté du 03/08/98 21:00:45 , vous avez écrit :
>
> l found this in the newbies.txt and does it have an error? it demonstrates
> the AND function:
>
> 76543210 ---------> bit number
> 01010101
> AND 01111000
> -------------
> 01111000
>
> shouldn't the result be 01010000 ?
Euh...
Yes ! Sorry.
Thius will be corrected in the next release.. ( don' t know when: when enough
errors are found. )
BTW:
>The simplest way to clear the upper word of d1 is:
>AND.L #$0000FFFF,d1
>(as far as I can tell)
It depends on the typê of data you are handling..
If you are sure that the lower word is smaller than %0111111111111111, then
you could use
ext.l d1
Which IS probably faster as it works just on some bits of the register...
However, i am not sure.. Perhaps is the number of clock cycles needed the
same.
Mathieu, <hmlacage@aol.com>