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Program Status Word: Difference between revisions
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! Flag Name !! Bit Position | ! Flag Name !! Bit Position | ||
|+ | |+ | ||
| Negative Flag || bit 7 | | [[Negative Flag]] || bit 7 | ||
|+ | |+ | ||
| | | [[Overflow Flag]] || bit 6 | ||
|+ | |+ | ||
| [[ | | [[Direct Page Flag]] || bit 5 | ||
|+ | |+ | ||
| [[Break Flag]] || bit 4 | | [[Break Flag]] || bit 4 | ||
| Line 18: | Line 18: | ||
| [[Interrupt Enable Flag]] || bit 2 | | [[Interrupt Enable Flag]] || bit 2 | ||
|+ | |+ | ||
| Zero Flag || bit 1 | | [[Zero Flag]] || bit 1 | ||
|+ | |+ | ||
| Carry | | [[Carry Flag]] || bit 0 | ||
|} | |} | ||
Both the [[PUSH]] and [[POP]] commands can operate on the PSW. | Both the [[PUSH]] and [[POP]] commands can operate on the PSW. | ||
=== See Also === | |||
* [[Processor Status Register]] | |||
=== Reference === | |||
* subparagraph 8.1.6, [https://archive.org/details/SNESDevManual/book1/page/n184 page 3-8-6 of Book I] of the official Super Nintendo development manual | |||
[[Category:ASM]] | [[Category:ASM]] | ||
Latest revision as of 14:13, 29 December 2023
The Program Status Word is an 8-bit register on the SPC700 that stores the values of status flags. They are typically listed in this order: NVPBHIZC. More verbosely:
| Flag Name | Bit Position |
|---|---|
| Negative Flag | bit 7 |
| Overflow Flag | bit 6 |
| Direct Page Flag | bit 5 |
| Break Flag | bit 4 |
| Half-carry flag | bit 3 |
| Interrupt Enable Flag | bit 2 |
| Zero Flag | bit 1 |
| Carry Flag | bit 0 |
Both the PUSH and POP commands can operate on the PSW.
See Also
Reference
- subparagraph 8.1.6, page 3-8-6 of Book I of the official Super Nintendo development manual