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DEC: Difference between revisions
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* [[Leventhal]] page on DEC: https://archive.org/details/6502-assembly-language-programming/page/n109 | * [[Leventhal]] page on DEC: https://archive.org/details/6502-assembly-language-programming/page/n109 | ||
* snes9x implementation of DEC: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L482 | * snes9x implementation of DEC: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L482 | ||
* undisbeliever on DEC: https://undisbeliever.net/snesdev/65816-opcodes.html#dec-decrement | |||
[[Category:ASM]] | [[Category:ASM]] | ||
Revision as of 04:04, 18 May 2023
DEC (Decrement) is a 65x instruction that decrements the value in the location specified by the operand.
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | Speed | ||||
| accumulator | 3A | 1 byte | 2 cycles | ||||
| absolute | CE | 3 bytes | 6 cycles | ||||
| direct page | C6 | 2 bytes | 5 cycles | ||||
| absolute indexed X | DE | 3 bytes | 7 cycles | ||||
| direct page indexed X | D6 | 2 bytes | 6 cycles | ||||
| Flags Clobbered | ||||||||
|---|---|---|---|---|---|---|---|---|
| N | V | M | X | D | I | Z | C | |
| . | . | . | . | . | . | |||
See Also
External Links
- Eyes & Lichty page on DEC: https://archive.org/details/0893037893ProgrammingThe65816/page/n477
- Labiak page on DEC: https://archive.org/details/Programming_the_65816/page/n148
- MCS6500 Manual page on DEC: https://archive.org/details/mos_microcomputers_programming_manual/page/n176
- Carr page on DEC: https://archive.org/details/6502UsersManual/page/n270
- Leventhal page on DEC: https://archive.org/details/6502-assembly-language-programming/page/n109
- snes9x implementation of DEC: https://github.com/snes9xgit/snes9x/blob/master/cpuops.cpp#L482
- undisbeliever on DEC: https://undisbeliever.net/snesdev/65816-opcodes.html#dec-decrement