We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS
BEQ: Difference between revisions
From SnesLab
(→External Links: Labiak page number) |
(linkify admode) |
||
| Line 7: | Line 7: | ||
|'''Speed''' | |'''Speed''' | ||
|+ | |+ | ||
| | |[[Program Counter Relative]] | ||
|F0 | |F0 | ||
|2 byte | |2 byte | ||
Revision as of 07:44, 28 November 2023
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | Speed | ||||
| Program Counter Relative | F0 | 2 byte | 2 cycles | ||||
| Flags Affected | ||||||||
|---|---|---|---|---|---|---|---|---|
| N | V | M | X | D | I | Z | C | |
| . | . | . | . | . | . | . | . | |
BEQ (Branch if Equal) is a 65x instruction that performs a jump if the zero flag is set.
Cycle Penalties
- BEQ takes an extra cycle if the branch is taken
- BEQ takes another extra cycle if the branch taken crosses a page boundary in emulation mode
See Also
External Links
- Eyes & Lichty page 430, on BEQ: https://archive.org/details/0893037893ProgrammingThe65816/page/n456
- Labiak page 120 on BEQ: https://archive.org/details/Programming_the_65816/page/n130
- MCS6500 Manual page on BEQ: https://archive.org/details/mos_microcomputers_programming_manual/page/n56
- Carr page on BEQ: https://archive.org/details/6502UsersManual/page/n262
- Leventhal page on BEQ: https://archive.org/details/6502-assembly-language-programming/page/n93
- snes9x implementation of BEQ: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1370