We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS

LDY: Difference between revisions

From SnesLab
Jump to: navigation, search
(→‎External Links: hide archive URL for E&L)
(→‎External Links: hid archive URL for Carr)
Line 80: Line 80:
* [[Labiak]], [https://archive.org/details/Programming_the_65816/page/n161 page 151] on LDY
* [[Labiak]], [https://archive.org/details/Programming_the_65816/page/n161 page 151] on LDY
* [[MCS6500 Manual]] page 96 on LDY: https://archive.org/details/mos_microcomputers_programming_manual/page/n114
* [[MCS6500 Manual]] page 96 on LDY: https://archive.org/details/mos_microcomputers_programming_manual/page/n114
* [[Carr]] page 264 on LDY: https://archive.org/details/6502UsersManual/page/n277
* [[Carr]], [https://archive.org/details/6502UsersManual/page/n277 page 264] on LDY
* [[Leventhal]] page 3-74 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

Revision as of 21:05, 6 August 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
N . . . . . Z .

LDY (Load Y) is a 65x instruction that loads a value into 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