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SEV (SEt Overflow) is a mnemonic for a non-existant 6502 instruction. | SEV (SEt Overflow) is a mnemonic for a non-existant 6502 instruction. | ||
To set the [[overflow flag]], consider using [[SEP]]. | To set the [[overflow flag]], consider using [[SEP]] or [[BIT]]. Like this: | ||
<pre> | |||
SEP #$40 | |||
</pre> | |||
A common way is to use BIT on the address of a byte in ROM that has bit 6 set, like an [[RTS]].<sup>[1]</sup> | |||
=== See Also === | === See Also === | ||
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=== External Links === | === External Links === | ||
# Clark, Bruce. http://www.6502.org/tutorials/vflag.html | |||
# [[Eyes & Lichty]], [https://archive.org/details/0893037893ProgrammingThe65816/page/263 page 263] | |||
[[Category:ASM]] | [[Category:ASM]] | ||
[[Category:Non-Existant Instructions]] | [[Category:Non-Existant Instructions]] | ||
Latest revision as of 01:50, 10 August 2024
SEV (SEt Overflow) is a mnemonic for a non-existant 6502 instruction.
To set the overflow flag, consider using SEP or BIT. Like this:
SEP #$40
A common way is to use BIT on the address of a byte in ROM that has bit 6 set, like an RTS.[1]
See Also
External Links
- Clark, Bruce. http://www.6502.org/tutorials/vflag.html
- Eyes & Lichty, page 263