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PEA: Difference between revisions
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''' | {| class="wikitable" style="float:right;clear:right;width:40%" | ||
!colspan="8"|Basic Info | |||
|+ | |||
|'''Addressing Mode''' | |||
|'''Opcode''' | |||
|'''Length''' | |||
|'''Speed''' | |||
|+ | |||
|[[Stack Addressing|Stack]] (absolute) | |||
|F4 | |||
|3 bytes | |||
|5 cycles | |||
|} | |||
{| class="wikitable" style="float:right;clear:right;width:30%" | {| class="wikitable" style="float:right;clear:right;width:30%" | ||
!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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|. | |. | ||
|} | |} | ||
'''PEA''' (Push Effective Address) is a [[65c816]] instruction that pushes a 16-bit value to the [[stack]]. This value need not actually be an address. The [[stack pointer]] is decremented by two. | |||
PEA can be thought of as using [[immediate addressing]], although the immediate syntax is not used. | |||
PEA ignores the state of the m and x flags. | |||
No flags are affected. | |||
==== Syntax ==== | |||
<pre> | |||
PEA addr | |||
PEA const | |||
</pre> | |||
PEA works even in [[emulation mode]]. | |||
=== See Also === | |||
* [[PER]] | |||
* [[PEI]] | |||
* [[PHA]] | |||
* [[TSC]] | |||
* [[XBA]] | |||
=== External Links === | |||
* [[Eyes & Lichty]], [https://archive.org/details/0893037893ProgrammingThe65816/page/473 page 473] on PEA | |||
* [[Labiak]], [https://archive.org/details/Programming_the_65816/page/n167 page 157] on PEA | |||
* snes9x implementation of PEA: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1631 | |||
* undisbeliever on PEA: https://undisbeliever.net/snesdev/65816-opcodes.html#pea-push-effective-absolute-address | |||
* Clark, Bruce. http://www.6502.org/tutorials/65c816opcodes.html#6.8.1 | |||
* https://wilsonminesco.com/816myths/65c816_myths-2_BDD.pdf | |||
[[Category:ASM]] | [[Category:ASM]] | ||
[[Category:65c816 additions]] | |||
[[Category:Push Instructions]] | |||
[[Category:Three-byte Instructions]] | |||
[[Category:Five-cycle Instructions]] | |||
Latest revision as of 22:58, 12 August 2024
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | Speed | ||||
| Stack (absolute) | F4 | 3 bytes | 5 cycles | ||||
| Flags Affected | ||||||||
|---|---|---|---|---|---|---|---|---|
| N | V | M | X | D | I | Z | C | |
| . | . | . | . | . | . | . | . | |
PEA (Push Effective Address) is a 65c816 instruction that pushes a 16-bit value to the stack. This value need not actually be an address. The stack pointer is decremented by two.
PEA can be thought of as using immediate addressing, although the immediate syntax is not used.
PEA ignores the state of the m and x flags. No flags are affected.
Syntax
PEA addr PEA const
PEA works even in emulation mode.
See Also
External Links
- Eyes & Lichty, page 473 on PEA
- Labiak, page 157 on PEA
- snes9x implementation of PEA: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L1631
- undisbeliever on PEA: https://undisbeliever.net/snesdev/65816-opcodes.html#pea-push-effective-absolute-address
- Clark, Bruce. http://www.6502.org/tutorials/65c816opcodes.html#6.8.1
- https://wilsonminesco.com/816myths/65c816_myths-2_BDD.pdf