We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS
BVC: Difference between revisions
From SnesLab
| (8 intermediate revisions by the same user not shown) | |||
| Line 7: | Line 7: | ||
|'''Speed''' | |'''Speed''' | ||
|+ | |+ | ||
| | |[[Program Counter Relative]] | ||
|50 | |50 | ||
|2 | |2 bytes | ||
|2 cycles* | |2 cycles* | ||
|} | |} | ||
| Line 16: | Line 16: | ||
!colspan="9"|Flags Affected | !colspan="9"|Flags Affected | ||
|+ | |+ | ||
|N | |[[Negative Flag|N]] | ||
|V | |[[Overflow Flag|V]] | ||
|M | |[[M Flag|M]] | ||
|X | |[[X Flag|X]] | ||
|D | |[[Decimal Flag|D]] | ||
|I | |[[I Flag|I]] | ||
|Z | |[[Zero Flag|Z]] | ||
|C | |[[Carry Flag|C]] | ||
|+ | |+ | ||
|. | |. | ||
| Line 46: | Line 46: | ||
=== External Links === | === External Links === | ||
* [[Eyes & Lichty]] page on BVC: https://archive.org/details/0893037893ProgrammingThe65816/page/n465 | * [[Eyes & Lichty]] page 439 on BVC: https://archive.org/details/0893037893ProgrammingThe65816/page/n465 | ||
* [[Labiak]] page on BVC: https://archive.org/details/Programming_the_65816/page/n138 | * [[Labiak]] page 128 on BVC: https://archive.org/details/Programming_the_65816/page/n138 | ||
* [[MCS6500 Manual]] page on BVC: https://archive.org/details/mos_microcomputers_programming_manual/page/n56 | * [[MCS6500 Manual]] page 41 on BVC: https://archive.org/details/mos_microcomputers_programming_manual/page/n56 | ||
* [[Carr]] page on BVC: https://archive.org/details/6502UsersManual/page/n265 | * [[Carr]] page 252 on BVC: https://archive.org/details/6502UsersManual/page/n265 | ||
* [[Leventhal]] page on BVC: https://archive.org/details/6502-assembly-language-programming/page/n100 | * [[Leventhal]] page 3-51 on BVC: https://archive.org/details/6502-assembly-language-programming/page/n100 | ||
* snes9x implementation of BVC: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1395 | * snes9x implementation of BVC: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1395 | ||
| Line 56: | Line 56: | ||
[[Category:Inherited from 6502]] | [[Category:Inherited from 6502]] | ||
[[Category:Conditional Branches]] | [[Category:Conditional Branches]] | ||
[[Category:Two-byte Instructions]] | |||
[[Category:Two-cycle Instructions]] | |||
Latest revision as of 11:45, 14 December 2023
| 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.
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: https://archive.org/details/0893037893ProgrammingThe65816/page/n465
- Labiak page 128 on BVC: https://archive.org/details/Programming_the_65816/page/n138
- MCS6500 Manual page 41 on BVC: https://archive.org/details/mos_microcomputers_programming_manual/page/n56
- Carr page 252 on BVC: https://archive.org/details/6502UsersManual/page/n265
- Leventhal page 3-51 on BVC: https://archive.org/details/6502-assembly-language-programming/page/n100
- snes9x implementation of BVC: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1395