Processors
Processors (Intel® Core™, Intel® Xeon®, etc); processor utilities and programs (Intel® Processor Identification Utility, Intel® Extreme Tuning Utility, Intel® Easy Streaming Wizard, etc.)

8085

shri
Beginner
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'DAD' instruction in 8085 works only with the HL pair. I just want to know that whether this instruction involves Accumulator in backend or not. 

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n_scott_pearson
Super User Retired Employee
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Oh man, stress my aging brain cells. I haven't looked at this stuff in 40 years!

DAD, Double Register Add, adds the contents of B&C, D&E, H&L or SP to the contents of H&L and places the result in H&L. Forms are:

DAD B ADD HL,BC 09 HL <- HL + BC
DAD D ADD HL,DE 19 HL <- HL + DE
DAD H ADD HL,HL 29 HL <- HL + HL
DAD SP ADD HL,SP 39 HL <- HL + SP

 

It can affect the Carry bit (CY), but I don't see it touching the Accumulator at all.

...S

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