Rabbit 2000 - Dec (Hl)

28 Rabbit 2000/3000 Microprocessor
Description
The data in the Accumulator is inverted (one’s complement).
Example
If the data in the Accumulator is 1100 0101, after the instruction CPL the Accumulator will contain
0011 1010.
Description
Decrements the byte whose address is:
• inwordregisterHL, or
• the data in index register IX plus a displacement value d,or
• the data in index register IY plus a displacement value d.
CPL
Opcode Instruction Clocks Operation
2F CPL 2 A=~A
Flags ALTD I/O
S Z L/V C F R SP S D
- - - - •
DEC (HL)
DEC (IX+d)
DEC (IY+d)
Opcode Instruction Clocks Operation
35 DEC (HL) 8 (2,1,2,3) (HL) = (HL) - 1
DD 35 d DEC (IX+D) 12 (2,2,2,1,2,3) (IX + d)=(IX+d)-1
FD 35 d DEC (IY+D) 12 (2,2,2,1,2,3) (IY + d)=(IY+d)-1
Flags ALTD I/O
S Z L/V C F R SP S D
• • V - • • •