RR Rotate bits right with Carry and store in register
Undocumented Rotate bits right with carry and store in register
This instruction performs an RR (IX+dd) or RR (IX+dd) operation but then also stores
the result in a register as well as in the memory location.
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
|---|---|---|---|---|---|---|---|---|
| RR r,(IX+d) | ||||||||
| 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | DD |
| 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | CB |
| d | ||||||||
| 0 | 0 | 0 | 1 | 1 | r | |||
| RR r,(IY+d) | ||||||||
| 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | FD |
| 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | CB |
| d | ||||||||
| 0 | 0 | 0 | 1 | 1 | r | |||
| Register | r |
|---|---|
| B | 000 |
| C | 001 |
| D | 010 |
| E | 011 |
| H | 100 |
| L | 101 |
| A | 111 |
Note: r=%110 does exist. It doesn't do a copy into a register as it's the existing official, documented instruction.
Opcode Matrix
| A | B | C | D | E | H | L | |
|---|---|---|---|---|---|---|---|
| (IX+d) |
RR A,(IX+d)
DDCBnn1F |
RR B,(IX+d)
DDCBnn18 |
RR C,(IX+d)
DDCBnn19 |
RR D,(IX+d)
DDCBnn1A |
RR E,(IX+d)
DDCBnn1B |
RR H,(IX+d)
DDCBnn1C |
RR L,(IX+d)
DDCBnn1D |
| (IY+d) |
RR A,(IY+d)
FDCBnn1F |
RR B,(IY+d)
FDCBnn18 |
RR C,(IY+d)
FDCBnn19 |
RR D,(IY+d)
FDCBnn1A |
RR E,(IY+d)
FDCBnn1B |
RR H,(IY+d)
FDCBnn1C |
RR L,(IY+d)
FDCBnn1D |
|
Instruction
Opcode hex
| Undocumented |
Last modified November 16, 2021: Optimise undocumented pages (5f13800)