We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS
POP (SPC700): Difference between revisions
From SnesLab
(→See Also: '816 pushes) |
(sp incremented before) |
||
| (2 intermediate revisions by the same user not shown) | |||
| Line 12: | Line 12: | ||
|4 cycles | |4 cycles | ||
|+ | |+ | ||
|[[Stack Addressing | Stack]] | |[[Stack Addressing | Stack]] - X | ||
|CE | |CE | ||
|1 byte | |1 byte | ||
|4 cycles | |4 cycles | ||
|+ | |+ | ||
|[[Stack Addressing | Stack]] | |[[Stack Addressing | Stack]] - Y | ||
|EE | |EE | ||
|1 byte | |1 byte | ||
|4 cycles | |4 cycles | ||
|+ | |+ | ||
|[[Stack Addressing | Stack]] | |[[Stack Addressing | Stack]] - PSW | ||
|8E | |8E | ||
|1 byte | |1 byte | ||
| Line 68: | Line 68: | ||
* the [[Y Index Register]] | * the [[Y Index Register]] | ||
* the [[program status word]] | * the [[program status word]] | ||
The [[stack pointer]] is incremented by one before the value is pulled. | |||
When the [[program status word]] is the operand, all the flags are naturally affected as that is the register they live in. Otherwise, no flags are affected. | When the [[program status word]] is the operand, all the flags are naturally affected as that is the register they live in. Otherwise, no flags are affected. | ||
Latest revision as of 03:52, 9 August 2024
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | Speed | ||||
| Accumulator | AE | 1 byte | 4 cycles | ||||
| Stack - X | CE | 1 byte | 4 cycles | ||||
| Stack - Y | EE | 1 byte | 4 cycles | ||||
| Stack - PSW | 8E | 1 byte | 4 cycles | ||||
| Flags Affected | ||||||||
|---|---|---|---|---|---|---|---|---|
| Operand is the PSW? | N | V | P | B | H | I | Z | C |
| yes | N | V | P | B | H | I | Z | C |
| no | . | . | . | . | . | . | . | . |
POP is an SPC700 command that pops a byte from the stack, pulling it into a register. The target register can be:
- the accumulator
- the X Index Register
- the Y Index Register
- the program status word
The stack pointer is incremented by one before the value is pulled.
When the program status word is the operand, all the flags are naturally affected as that is the register they live in. Otherwise, no flags are affected.
Syntax
POP A POP X POP Y POP PSW
See Also
References
- Table C-17 in Appendix C-9 of Book I of the official Super Nintendo development manual
- anomie: https://github.com/yupferris/TasmShiz/blob/master/spc700.txt#L536