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LDY: Difference between revisions

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* snes9x implementation of LDY: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L817
* snes9x implementation of LDY: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L817
* undisbeliever on LDY: https://undisbeliever.net/snesdev/65816-opcodes.html#ldy-load-index-register-y-from-memory
* undisbeliever on LDY: https://undisbeliever.net/snesdev/65816-opcodes.html#ldy-load-index-register-y-from-memory
* http://www.6502.org/tutorials/6502opcodes.html#LDY
* Pickens, John. http://www.6502.org/tutorials/6502opcodes.html#LDY


[[Category:ASM]]
[[Category:ASM]]

Revision as of 12:35, 22 July 2024

Basic Info
Addressing Mode Opcode Length Speed
Immediate A0 2/3 bytes 2 cycles*
Absolute AC 3 bytes 4 cycles*
Direct Page A4 2 bytes 3 cycles*
Absolute Indexed by X BC 3 bytes 4 cycles*
Direct Page Indexed by X B4 2 bytes 4 cycles*
Flags Affected
N V M X D I Z C
. . . . . .

LDY (Load Y) is a 65x instruction that loads the Y index register. In immediate addressing only, LDY takes a total of 3 bytes when the index registers are 16 bits wide.

Syntax

LDY #const
LDY addr
LDY dp
LDY addr, X
LDY dp, X
Cycle Penalties

See Also

External Links