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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.
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!colspan="8"|Basic Info
!colspan="8"|Basic Info
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|'''Speed'''
|'''Speed'''
|+
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|implied
|[[Stack Addressing|Stack]] (absolute)
|F4
|F4
|3 bytes
|3 bytes
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!colspan="9"|Flags Clobbered
!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 ===
=== External Links ===
* [[Eyes & Lichty]] page on PEA: https://archive.org/details/0893037893ProgrammingThe65816/page/n499
* [[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: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