CHAPTER 6 DETAILED RULES FOR EXECUTION INSTRUCTIONS
6.72SUBC (SUBtract Byte Data of Memory from Accumulator with Carry to Accumulator)
Subtract the byte data of the EA memory (memory expressed in each type of addressing) from that of AL, subtract a carry and then return the results to AL. The contents of AH are not changed.
■SUBC (SUBtract Byte Data of Memory from Accumulator with Carry to Accumulator)
Operation
(AL) ← (AL) - (EA) - C (Byte subtraction with carry)
Assembler format
SUBC A, EA
Condition code (CCR)
N | Z | V | C |
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+ | + | + | + |
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+: Changed by executing instruction
N:Set to 1 if the MSB of AL is 1 as the result of operation and set to 0 in other cases.
Z:Set to 1 if the result of operation is 00H and set to 0 in other cases.
V:Set to 1 if an overflow occurs as the result of operation and set to 0 in other cases.
C:Set to 1 if a carry occurs as the result of operation and set to 0 in other cases.
Table 6.72-1 Number of Execution Cycles / Byte Count / OP Code
EA | #d8 | dir | @IX+off | @EP | Ri | |
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Number of | 2 | 3 | 3 | 2 | 2 | |
execution cycles | ||||||
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Byte count | 2 | 2 | 2 | 1 | 1 | |
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OP code | 34 | 35 | 36 | 37 | 38 to 3F | |
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190
