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MICROPROCESSOR INSTRUCTION REFERENCE->SUB
SUB Subract Memory from Register
SUBA
SUBB
SUBD
A <- A - M or B <- B - M or D <- D - M
Condition Code Register:
H Undefined
N Set if result Negative, else cleared
Z Set if result Zero, else cleared
V Set on overflow, else cleared
C Set if borrow, else cleared
Addressing mode | No of cycles | No of bytes |
Immed.: | 2 (4) | 2 (3) |
Direct: | 4 (6) | 2 (2) |
Extended: | 5 (7) | 3 (3) |
Index/Indirect: | 4+ (6+) | 2+ (2+) | Bracketed values refer to double accum. |