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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
| [[Overflow Flag]] || bit 6
|+
|+
| [[direct page flag]] || bit 5
| [[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 flag || bit 0
| [[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