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BVC: Difference between revisions
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==== Cycle Penalties ==== | |||
* BVC takes one extra cycle if the branch is taken | * BVC takes one extra cycle if the branch is taken | ||
* BVC takes another extra cycle if that branch taken crosses a page boundary in [[emulation mode]]. | * BVC takes another extra cycle if that branch taken crosses a page boundary in [[emulation mode]]. | ||
Latest revision as of 17:42, 23 August 2024
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | Speed | ||||
| Program Counter Relative | 50 | 2 bytes | 2 cycles* | ||||
| Flags Affected | ||||||||
|---|---|---|---|---|---|---|---|---|
| N | V | M | X | D | I | Z | C | |
| . | . | . | . | . | . | . | . | |
BVC is a 65x instruction that performs a branch if the overflow flag is clear. If the overflow flag is set, control simply falls through to the next instruction.
No flags are affected.
Syntax
BVC nearlabel
Cycle Penalties
- BVC takes one extra cycle if the branch is taken
- BVC takes another extra cycle if that branch taken crosses a page boundary in emulation mode.
See Also
External Links
- Eyes & Lichty, page 439 on BVC
- Labiak, page 128 on BVC
- 4.1.2.8 on MCS6500 Manual, page 41 on BVC
- Carr, page 252 on BVC
- Leventhal, page 3-51 on BVC
- snes9x implementation of BVC: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1395