[Coco] Assembler Question???

uhmgawa uhmgawa at third-harmonic.com
Wed Sep 2 17:52:12 EDT 2009

jdaggett at gate.net wrote:

>> I don't believe that is the case as a subtract
>> operation sets the carry to the inverse of that
>> resulting from an add operation.  So in this
>> respect subtraction of x and addition of -x
>> aren't trivially interchangeable.
> Yes with subtraction you treat the carry differently. I understand that. What I needed to 
> know was when the subtrahend is converted to 2's compliment, at assembly or internally 
> in the ALU. I now know that it is internal and all is well. 

My point rather was given the disposition of the
carry bit after a subtract operation being
opposite from that of an addition, the data is
being interpreted as unsigned in both operations.

uhmgawa at third-harmonic.com

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