Legacy apps in Windows/OS X was Re: Old MS-DOS & Win Software

[Jim Leonard]

Tony Duell wrote:
>>Chuck Guzis wrote:
>>
>>>codes.  Inspection of the 808x instruction set can be very illuminiating,
>>>particularly when it comes to arcana like which instructions modify (and
>>>how) the half-carry flag, for example.
>>
>>The "half-carry flag"?  Huh?
> 
> I believe it's a flag indicating a carry from the low nybble to the high 
> nybble of the accumulator. That is, it indicates a carry out from the low 
> half of the byte. 
> It's mainly needed for BCD operations if memory serves.

Is this "half-carry" flag addressable, or is it just something internal?  A 
quick gander at 808x flags doesn't show a "half-carry" flag, unless I'm missing 
something obvious.
-- 
Jim Leonard (trixter at oldskool.org)                    http://www.oldskool.org/
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