Talk:ND-100 Status Flags: Difference between revisions

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(Created page with "Is the K bit also affected by the add and subtract instructions? Since it says it uses the one bit accumulator I mean. Roger 14:06, 30 April 2011 (AWST)")
 
(Re: K-bit)
 
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Since it says it uses the one bit accumulator I mean.
Since it says it uses the one bit accumulator I mean.
[[User:Roger|Roger]] 14:06, 30 April 2011 (AWST)
[[User:Roger|Roger]] 14:06, 30 April 2011 (AWST)
:I assume you refer to the 'extra' bit I described in the Carry description. If so, then I believe (with no physical ND-100 available to me anymore) the answer is "no". The K bit (one-bit accumulator) is as far as I can tell only affected by the BOP instructions. The 'extra' bit which I used to describe how Carry works is in one way a construct (used to show _why_ the C bit ends up as it does), but in another way it probably exists physically in the ALU: Even though it's only implictly used by SUB it can be manipulated explictly by the ROP instructions after all, using the AD1 and CLD modifiers. [[User:TArntsen|TArntsen]] 15:37, 30 April 2011 (CEST)

Latest revision as of 13:37, 30 April 2011

Is the K bit also affected by the add and subtract instructions? Since it says it uses the one bit accumulator I mean. Roger 14:06, 30 April 2011 (AWST)

I assume you refer to the 'extra' bit I described in the Carry description. If so, then I believe (with no physical ND-100 available to me anymore) the answer is "no". The K bit (one-bit accumulator) is as far as I can tell only affected by the BOP instructions. The 'extra' bit which I used to describe how Carry works is in one way a construct (used to show _why_ the C bit ends up as it does), but in another way it probably exists physically in the ALU: Even though it's only implictly used by SUB it can be manipulated explictly by the ROP instructions after all, using the AD1 and CLD modifiers. TArntsen 15:37, 30 April 2011 (CEST)