AMD Am186 Series, Instruction Set

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Instruction Set 4-11
ADC ADC
Flag Settings After Instruction
Examples
This example adds two 32-bit unsigned numbers.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Processor Status
Flags Register
reserved
OF DF IF TF SF ZF AF PF CF
? = undefined; – = unchanged
OF=1 if result larger than destination operand
OF=0 otherwise
AF=1 if carry or borrow to low nibble
AF=0 otherwise
PF=1 if low byte of result has even number of set bits
PF=0 otherwise
CF=1 for carry or borrow to high-order bit
CF=0 otherwise
– – – res res res
SF=1 if result is 0 or positive
SF=0 if result is negative
ZF=1 if result equal to 0
ZF=0 if result not equal to 0
UADDEND1 DD 592535620 ; 23516044h
UADDEND2 DD 3352720 ; 00332890h
; 32-bit unsigned addition: UADDEND1 = UA UADDEND2
; add left words (bytes and words reversed in memory)
MOV AX,WORD PTR UADDEND2
ADD WORD PTR UADDEND1,AX
; add right words
MOV AX,WORD PTR U2
ADC WORD PTR U2,AX ; UADDEND1 = 238488D4h
; = 595888340