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BRA: Difference between revisions
From SnesLab
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|'''Speed''' | |'''Speed''' | ||
|+ | |+ | ||
| | |[[Program Counter Relative]] | ||
|80 | |80 | ||
|2 byte | |2 byte | ||
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!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]] | ||
|+ | |+ | ||
|. | |. | ||
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|} | |} | ||
'''BRA''' (BRanch Always) is a [[65c816]] instruction that performs an unconditional jump. | '''BRA''' (BRanch Always) is a [[65c816]] instruction that performs an unconditional jump. The signed displacement ranges from -128 to 127. | ||
BRA is relocatable. | |||
===== Cycle Penalty ===== | ===== Cycle Penalty ===== | ||
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=== External Links === | === External Links === | ||
* [[Eyes & Lichty]] page 435, on BRA: https://archive.org/details/0893037893ProgrammingThe65816/page/n461 | * [[Eyes & Lichty]] page 435, on BRA: https://archive.org/details/0893037893ProgrammingThe65816/page/n461 | ||
* [[Labiak]] page on BRA: https://archive.org/details/Programming_the_65816/page/n135 | * [[Labiak]] page 125 on BRA: https://archive.org/details/Programming_the_65816/page/n135 | ||
* snes9x implementation of BRA: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1390 | * snes9x implementation of BRA: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1390 | ||
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[[Category:65c02 additions]] | [[Category:65c02 additions]] | ||
[[Category:Unconditional Branches]] | [[Category:Unconditional Branches]] | ||
[[Category:Two-byte Instructions]] | |||
[[Category:Relocatable Instructions]] | |||
[[Category:Single Admode Mnemonics]] |
Latest revision as of 12:45, 14 December 2023
Basic Info | |||||||
---|---|---|---|---|---|---|---|
Addressing Mode | Opcode | Length | Speed | ||||
Program Counter Relative | 80 | 2 byte | 3 cycles* |
Flags Affected | ||||||||
---|---|---|---|---|---|---|---|---|
N | V | M | X | D | I | Z | C | |
. | . | . | . | . | . | . | . |
BRA (BRanch Always) is a 65c816 instruction that performs an unconditional jump. The signed displacement ranges from -128 to 127.
BRA is relocatable.
Cycle Penalty
- BRA takes one additional cycle if the branch crosses a page boundary in emulation mode.
See Also
External Links
- Eyes & Lichty page 435, on BRA: https://archive.org/details/0893037893ProgrammingThe65816/page/n461
- Labiak page 125 on BRA: https://archive.org/details/Programming_the_65816/page/n135
- snes9x implementation of BRA: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1390