KS57C2308/P2308/C2316/P2316 SAM47 INSTRUCTION SET
5-25
ADC — Add With Carry
ADC (Continued)
Examples: 3. If ADC A,@HL is followed by an ADS A,#im, the ADC skips on carry to the instruction
immediately after the ADS. An ADS instruction immediately after the ADC does not skip even
if an overflow occurs. This function is useful for decimal adjustment operations.
a. 8 + 9 decimal addition (the contents of the address specified by the HL register is 9H):
RCF ;C ← "0"
LD A,#8H ;A ← 8H
ADS A,#6H ;A ← 8H + 6H = 0EH
ADC A,@HL ;A ← 0EH + 9H + C(0) = 7H, C ← "1"
ADS A,#0AH ;Skip this instruction because C = "1" after ADC result
JPS XXX
b. 3 + 4 decimal addition (the contents of the address specified by the HL register is 4H):
RCF ;C ← "0"
LD A,#3H ;A ← 3H
ADS A,#6H;A ← 3H + 6H = 9H
ADC A,@HL ;A ← 9H + 4H + C(0) = 0DH
ADS A,#0AH ;No skip. A ← 0DH + 0AH = 7H
;(The skip function for “ADS A,#im” is inhibited after an
;“ADC A,@HL” instruction even if an overflow occurs.)
JPS XXX