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DEC (SPC700): Difference between revisions
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!colspan="8"|Basic Info | !colspan="8"|Basic Info | ||
|+ | |+ | ||
| Line 9: | Line 7: | ||
|'''Speed''' | |'''Speed''' | ||
|+ | |+ | ||
| | |[[Accumulator Addressing | Accumulator]] | ||
|9C | |9C | ||
|1 byte | |1 byte | ||
|2 cycles | |2 cycles | ||
|+ | |+ | ||
| | |[[Direct Page Addressing | Direct Page]] | ||
|8B | |8B | ||
|2 byte | |2 byte | ||
|4 cycles | |4 cycles | ||
|+ | |+ | ||
| | |[[Direct Page Indexed by X]] | ||
|9B | |9B | ||
|2 byte | |2 byte | ||
|5 cycles | |5 cycles | ||
|+ | |+ | ||
| | |[[Absolute Addressing | Absolute]] | ||
|8C | |8C | ||
|3 bytes | |3 bytes | ||
|5 cycles | |5 cycles | ||
|+ | |+ | ||
| | |[[Implied]] (type 1) | ||
|1D | |1D | ||
|1 byte | |1 byte | ||
|2 cycles | |2 cycles | ||
|+ | |+ | ||
| | |[[Implied]] (type 1) | ||
|DC | |DC | ||
|1 byte | |1 byte | ||
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!colspan="8"|Flags | !colspan="8"|Flags Affected | ||
|+ | |+ | ||
|N | |[[Negative Flag|N]] | ||
|V | |[[Overflow Flag|V]] | ||
|P | |[[Direct Page Flag|P]] | ||
|B | |[[Break Flag|B]] | ||
|H | |[[Half-Carry Flag|H]] | ||
|I | |[[Interrupt Enable Flag|I]] | ||
|Z | |[[Zero Flag|Z]] | ||
|C | |[[Carry Flag|C]] | ||
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|} | |} | ||
'''DEC''' is an [[SPC700]] instruction that decrements its operand. | |||
=== See Also === | === See Also === | ||
* [[DEC]] | * [[DEC]] | ||
* [[INC (SPC700)]] | |||
* [[DEX]] | |||
* [[DEY]] | |||
=== External Links === | === External Links === | ||
* Official Nintendo | * Official Super Nintendo development manual on DEC: [https://archive.org/details/SNESDevManual/book1/page/n232 Appendix C-7 of Book I] | ||
[[Category:ASM]] | [[Category:ASM]] | ||
[[Category:SPC700]] | [[Category:SPC700]] | ||
[[Category:Addition and Subtraction Commands]] | [[Category:Addition and Subtraction Commands]] | ||
Latest revision as of 05:01, 27 November 2023
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | Speed | ||||
| Accumulator | 9C | 1 byte | 2 cycles | ||||
| Direct Page | 8B | 2 byte | 4 cycles | ||||
| Direct Page Indexed by X | 9B | 2 byte | 5 cycles | ||||
| Absolute | 8C | 3 bytes | 5 cycles | ||||
| Implied (type 1) | 1D | 1 byte | 2 cycles | ||||
| Implied (type 1) | DC | 1 byte | 2 cycles | ||||
| Flags Affected | |||||||
|---|---|---|---|---|---|---|---|
| N | V | P | B | H | I | Z | C |
| . | . | . | . | . | . | ||
DEC is an SPC700 instruction that decrements its operand.
See Also
External Links
- Official Super Nintendo development manual on DEC: Appendix C-7 of Book I