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PER: Difference between revisions
From SnesLab
(→Syntax: some assemblers accept # syntax) |
(works in emulation mode) |
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Assemblers that accept PER with the # syntax are rare. | Assemblers that accept PER with the # syntax are rare. | ||
PER works even in [[emulation mode]]. | |||
=== See Also === | === See Also === | ||
Revision as of 14:38, 4 August 2024
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | Speed | ||||
| Stack (PC Relative Long) | 62 | 3 bytes | 6 cycles | ||||
| Flags Affected | ||||||||
|---|---|---|---|---|---|---|---|---|
| N | V | M | X | D | I | Z | C | |
| . | . | . | . | . | . | . | . | |
PER (Push pc RElative indirect Address) is a 65c816 instruction that pushes a 16-bit sum to the stack. The addends are:
- the program counter after it has been incremented to point to the instruction following PER, and
- the 16-bit displacement following the PER opcode.
The high byte of the sum is pushed before the low byte.
No flags are affected. Neither the program bank register or program counter are modified either.
Syntax
PER label PER #label
Assemblers that accept PER with the # syntax are rare.
PER works even in emulation mode.
See Also
External Links
- Eyes & Lichty page 475, on PER: https://archive.org/details/0893037893ProgrammingThe65816/page/475
- Labiak page 159 on PER: https://archive.org/details/Programming_the_65816/page/n169
- snes9x implementation of PER: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1685
- undisbeliever on PER: https://undisbeliever.net/snesdev/65816-opcodes.html#per-push-effective-pc-relative-indirect-address
- Clark, Bruce. http://www.6502.org/tutorials/65c816opcodes.html#6.8.1