CHAPTER 6 DETAILED RULES FOR EXECUTION INSTRUCTIONS
6.29 DECW (DECrement Word Data of Accumulator)
Decrement word data of A by one.
■DECW (DECrement Word Data of Accumulator)
Operation
(A) ← (A) - 1 (Word subtraction)
Assembler format
DECW A
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 is 1 as the result of operation and set to 0 in other cases.
Z:Set to 1 if the result of operation is 0000H and set to 0 in other cases.
V:Not changed
C:Not changed
Number of execution cycle: 1
Byte count: 1
OP code: D0
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