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Processor Status Register: Difference between revisions

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(bit numbers)
(LDP does not store the reg)
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* [[SEI]]
* [[SEI]]
* [[CLV]]
* [[CLV]]
LDP does not exist, and STP does not store the register anywhere.


Several other instructions affect the flags as a side effect.  The only transfer instructions that do not modify these flags are [[TCS]] and [[TXS]].
Several other instructions affect the flags as a side effect.  The only transfer instructions that do not modify these flags are [[TCS]] and [[TXS]].

Revision as of 02:18, 25 July 2024

The Processor Status Register (P) is on the 65c816 and contains several flags:

It can be pulled from the stack via PLP and RTI.

There are nine instructions that directly modify these flags, including:[3]

LDP does not exist, and STP does not store the register anywhere.

Several other instructions affect the flags as a side effect. The only transfer instructions that do not modify these flags are TCS and TXS.

These instructions do not modify any status flags:

See Also

References

  1. Table 18.2 Eyes & Lichty, page 422: https://archive.org/details/0893037893ProgrammingThe65816/page/422
  2. Figure 17.3, Lbid, page 377: https://archive.org/details/0893037893ProgrammingThe65816/page/377
  3. page 262, https://archive.org/details/0893037893ProgrammingThe65816/page/262