Difference between revisions of "Z80 wait instructions"
From MSX Game Library
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Z80 instruction set that don't change registers value (except for F register): | Z80 instruction set that don't change registers value (except for F register): | ||
{| class="wikitable" | {| class="wikitable" | ||
| − | ! Inst. !! | + | ! Inst. !! TS !! Bytes !! Flag modification |
|- | |- | ||
| <tt>NOP</tt> || 5 || 1 || None | | <tt>NOP</tt> || 5 || 1 || None | ||
Revision as of 00:10, 3 March 2024
Z80 instruction set that don't change registers value (except for F register):
| Inst. | TS | Bytes | Flag modification |
|---|---|---|---|
| NOP | 5 | 1 | None |
| OR 0 | 8 | 2 | C and N flags cleared, P/V detects parity, and rest are modified by definition. |
| NOP NOP |
10 | 2 | None |
| LD R,A | 11 | 2 | ??? |
| NOP OR 0 |
13 | 3 | C and N flags cleared, P/V detects parity, and rest are modified by definition. |
| BIT 0,(HL) | 14 | 2 | Opposite of the bit #0 is written into the Z flag. C is preserved, N is reset, H is set, and S and P/V are undefined. |
| NOP NOP NOP |
15 | 3 | None |
| CP (IY+0) | 21 | 3 | ??? |
| BIT 0,(IY+0) | 22 | 4 | ??? |