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# lbid. https://www.righto.com/2013/01/a-small-part-of-6502-chip-explained.html?m=1
# lbid. https://www.righto.com/2013/01/a-small-part-of-6502-chip-explained.html?m=1
# Labiak. https://archive.org/details/Programming_the_65816/page/n118
# Labiak. https://archive.org/details/Programming_the_65816/page/n118
* Pickens, John.  NMOS 6502 Opcodes.  http://www.6502.org/tutorials/6502opcodes.html#VFLAG


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Revision as of 04:17, 21 July 2024

The Overflow Flag (V) is affected only by the following eight instructions:

It may be the most misunderstood flag of the 65c816.[2] It is bit 6 of the status register.

There is no SEV instruction to directly set the overflow flag, but the 6502 and 65c02 do have a hardware signal to set it.

On the SPC700 it can be cleared with CLRV and is set whenever the half-carry flag is set.

See Also

References

  1. Eyes & Lichty, page 439: https://archive.org/details/0893037893ProgrammingThe65816/page/439
  2. Clark, Bruce. http://www.6502.org/tutorials/vflag.html
  3. Shirriff, Ken. https://www.righto.com/2012/12/the-6502-overflow-flag-explained.html?m=1
  4. lbid. https://www.righto.com/2013/01/a-small-part-of-6502-chip-explained.html?m=1
  5. Labiak. https://archive.org/details/Programming_the_65816/page/n118