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Processor Status Register: Difference between revisions
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The '''Processor Status Register''' (P) is on the [[65c816]] and contains several flags: | The '''Processor Status Register''' (P) is on the [[65c816]] and contains several flags: | ||
* | * [[Negative Flag]] - N | ||
* | * [[Overflow Flag]] - V | ||
* m | * m | ||
* x | * x | ||
* d | * d | ||
* i | * i | ||
* | * [[Zero Flag]] - Z | ||
* | * [[Carry Flag]] - C | ||
It can be pulled from the [[stack]] via [[PLP]] and [[RTI]]. | It can be pulled from the [[stack]] via [[PLP]] and [[RTI]]. |
Revision as of 11:36, 17 July 2024
The Processor Status Register (P) is on the 65c816 and contains several flags:
- Negative Flag - N
- Overflow Flag - V
- m
- x
- d
- i
- Zero Flag - Z
- Carry Flag - C
It can be pulled from the stack via PLP and RTI.
There are nine instructions that directly modify these flags, including:[3]
The only transfer instructions that do not modify these flags are TCS and TXS.
See Also
Reference
- Table 18.2 Eyes & Lichty, page 422: https://archive.org/details/0893037893ProgrammingThe65816/page/422
- Figure 17.3, Lbid, page 377: https://archive.org/details/0893037893ProgrammingThe65816/page/n403
- page 262, https://archive.org/details/0893037893ProgrammingThe65816/page/n288