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PHY: Difference between revisions
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!colspan="8"|Basic Info | !colspan="8"|Basic Info | ||
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|'''Speed''' | |'''Speed''' | ||
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| | |[[Stack Addressing|Stack]] (Push) | ||
|5A | |5A | ||
|1 byte | |1 byte | ||
|3 cycles | |3 cycles* | ||
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!colspan="9"|Flags | !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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'''PHY''' is a [[65c816]] instruction that pushes the value of the [[Y index register]] onto the [[stack]]. If Y is 16 bits wide, the high byte is pushed first. | |||
The [[stack pointer]] is decremented by the number of bytes Y is. | |||
No flags are affected. | |||
==== Syntax ==== | |||
<pre> | |||
PHY | |||
</pre> | |||
==== Cycle Penalty ==== | |||
* PHY takes one additional cycle if the index registers are 16 bits wide. | |||
=== See Also === | |||
* [[PHX]] | |||
* [[PHA]] | |||
* [[PLY]] | |||
* [[STY]] | |||
=== External Links === | |||
* [[Eyes & Lichty]], [https://archive.org/details/0893037893ProgrammingThe65816/page/482 page 482] on PHY | |||
* [[Labiak]], [https://archive.org/details/Programming_the_65816/page/n176 page 166] on PHY | |||
* snes9x implementation of PHY: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1921 | |||
[[Category:ASM]] | [[Category:ASM]] | ||
[[Category:65c02 additions]] | |||
[[Category:Push Instructions]] | |||
[[Category:One-byte Instructions]] | |||
Latest revision as of 00:05, 17 August 2024
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | Speed | ||||
| Stack (Push) | 5A | 1 byte | 3 cycles* | ||||
| Flags Affected | ||||||||
|---|---|---|---|---|---|---|---|---|
| N | V | M | X | D | I | Z | C | |
| . | . | . | . | . | . | . | . | |
PHY is a 65c816 instruction that pushes the value of the Y index register onto the stack. If Y is 16 bits wide, the high byte is pushed first.
The stack pointer is decremented by the number of bytes Y is.
No flags are affected.
Syntax
PHY
Cycle Penalty
- PHY takes one additional cycle if the index registers are 16 bits wide.
See Also
External Links
- Eyes & Lichty, page 482 on PHY
- Labiak, page 166 on PHY
- snes9x implementation of PHY: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1921