Nintendo DMG-01 - Game Boy Console Manual page 93

TM
Game Boy CPU Manual
4. DEC nn
Description:
Decrement register nn.
Use with:
nn = BC,DE,HL,SP
Flags affected:
None.
Opcodes:
Instruction
DEC
DEC
DEC
DEC
by DP
Parameters
BC
DE
HL
SP
3.3.4. 16-Bit Arithmetic
Opcode Cycles
0B 8
1B 8
2B 8
3B 8
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