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LDY: Difference between revisions

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* [[MCS6500 Manual]] page on LDY: https://archive.org/details/mos_microcomputers_programming_manual/page/n114
* [[MCS6500 Manual]] page on LDY: https://archive.org/details/mos_microcomputers_programming_manual/page/n114
* [[Carr]] page on LDY: https://archive.org/details/6502UsersManual/page/n277
* [[Carr]] page on LDY: https://archive.org/details/6502UsersManual/page/n277
* [[Leventhal]] page on LDY: https://archive.org/details/6502-assembly-language-programming/page/n123
* [[Leventhal]] page 3-74 on LDY: https://archive.org/details/6502-assembly-language-programming/page/n123
* 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

Revision as of 10:55, 4 December 2023

Basic Info
Addressing Mode Opcode Length Speed
Immediate A0 2 bytes 2 cycles*
Absolute AC 3 bytes 4 cycles*
Direct Page A4 2 bytes 3 cycles*
absolute indexed X BC 3 bytes 4 cycles*
direct page indexed 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.

Cycle Penalties

See Also

External Links