INC increments either an 8-bit register or an 16-bit register pair.
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INC increments either an 8-bit register or an 16-bit register pair.
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
|---|---|---|---|---|---|---|---|---|
| \(s \longleftarrow r + 1\) | ||||||||
| INC r | ||||||||
| 0 | 0 | r | 1 | 0 | 0 | |||
| \((HL) \longleftarrow (HL) + 1\) | ||||||||
| INC (HL) | ||||||||
| 0 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 34 |
| \((IX+d) \longleftarrow (IX+d) + 1\) | ||||||||
| INC (IX+d) | ||||||||
| 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | DD |
| 0 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 34 |
| d | ||||||||
| \((IY+d) \longleftarrow (IY+d) + 1\) | ||||||||
| INC (IY+d) | ||||||||
| 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | FD |
| 0 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 34 |
| d | ||||||||
| Register | r |
|---|---|
| B | 000 |
| C | 001 |
| D | 010 |
| E | 011 |
| H | 100 |
| L | 101 |
| A | 111 |
| Flags |
| ||||||||
|---|---|---|---|---|---|---|---|---|---|
| s | set if result negative | ||||||||
| z | set if result is 0 | ||||||||
| h | set if carry from bit 3 | ||||||||
| p/v | set if register was 0x7F before operation, reset otherwise |
| A | B | C | D | E | H | L | (HL) | (IX+d) | (IY+d) | |
|---|---|---|---|---|---|---|---|---|---|---|
| Op |
INC A
3C14 |
INC B
0414 |
INC C
0C14 |
INC D
1414 |
INC E
1C14 |
INC H
2414 |
INC L
2C14 |
INC (HL)
34111 |
INC (IX+d)
DD34nn323 |
INC (IY+d)
FD34nn323 |
|
Instruction
Opcode hexSize bytesCycle count
| Register | Memory |
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
|---|---|---|---|---|---|---|---|---|
| \(dd \longleftarrow dd + 1\) | ||||||||
| INC qq | ||||||||
| 0 | 0 | dd | 0 | 0 | 1 | 1 | ||
| \(IX \longleftarrow IX + 1\) | ||||||||
| INC IX | ||||||||
| 1 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | DD |
| 0 | 0 | 1 | 0 | 0 | 0 | 1 | 1 | 23 |
| \(IY \longleftarrow IY + 1\) | ||||||||
| INC IY | ||||||||
| 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | FD |
| 0 | 0 | 1 | 0 | 0 | 0 | 1 | 1 | 23 |
| Value | dd |
|---|---|
| 00 | BC |
| 01 | DE |
| 10 | HL |
| 11 | SP |
| None. |
| BC | DE | HL | SP | IX | IY | |
|---|---|---|---|---|---|---|
| Op |
INC BC
0316 |
INC DE
1316 |
INC HL
2316 |
INC SP
3316 |
INC IX
DD23210 |
INC IY
FD23210 |
|
Instruction
Opcode hexSize bytesCycle count
| Register |