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Program Status Word: Difference between revisions

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The '''Program Status Word''' is an 8-bit register on the [[SPC700]] that stores the value of status flags.  They are typically listed in this order: NVPBHIZC.  More verbosely:
The '''Program Status Word''' is an 8-bit register on the [[SPC700]] that stores the value of status flags.  They are typically listed in this order: NVPBHIZC.  More verbosely:


* Negative Flag - bit 7
{| class="wikitable"
* overflow Flag - bit 6
!colspan="2"|
* [[direct page flag]] - bit 5
|+
* [[Break Flag]] - bit 4
! Flag Name !! Bit Position
* [[Half-carry flag]] - bit 3
|+
* [[Interrupt Enable Flag]] - bit 2
| Negative Flag || bit 7
* Zero Flag - bit 1
|+
* Carry flag - bit 0
| 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
|}


[[Category:ASM]]
[[Category:ASM]]
[[Category:SPC700]]
[[Category:SPC700]]
[[Category:Flags]]
[[Category:Flags]]

Revision as of 22:53, 15 July 2023

The Program Status Word is an 8-bit register on the SPC700 that stores the value 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