Keep DAA! (was Re: 8086 bugs)

[J.C. Wren]

Noooooo........!  DAA has a very useful function.

    AND AL,00fh
    ADD AL,090h
    DAA
    ADC AL,040h
    DAA
    RET

Now, what's it do?
   
    --jc

Chuck Guzis wrote:

>On 12/9/2005 at 9:16 PM Jim Battle wrote:
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>>On pages 97-98 he is discussing flags and DAA.  He mentions that the only
>>flag that really needs to be changed on a DAA is the carry flag, but to
>>increase compatibility with 8080 code, they set all five flags like the
>>    
>>
>8080.  
>
>Which brings us back to the original subject, doesn't it?  Current fancy
>x86 still harks from the 8008 in that the old DAA is STILL there, although
>heaven knows who still uses it (or why.  I know the 4004 also had a DAA,
>but I don't count it as the 8008 doesn't really descend from the 4004).
>
>Maybe it's time to say goodbye to DAA and the rest of the cruft.
>
>Cheers,
>Chuck
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