ADC instruction in ASM 8086

assembly x86-16 machine-instruction
Tal picture Tal · Apr 22, 2010 · Viewed 30.8k times · Source

When I use ADC for exmaple:

AL = 01 and BL = 02, and CF = 1

when I make this: 

ADC AL,BL

Will AL be 3 or 4? (with the CF addition or without?)

Answer

codaddict picture codaddict · Apr 22, 2010

Few things about the 8086 ADC instruction:

Syntax: adc dest, src
dest: memory or register
src:  memory, register, or immediate
Action: dest = dest + src + CF

Clearly the action says the Carry Flag (CF) will be included in the addition so the result will be 4 not 3.

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