Re: A86: More beginner questions
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Re: A86: More beginner questions
In a message dated 5/12/98 6:56:51 PM Central Daylight Time,
assets@eden.rutgers.edu writes:
> af isn't a valid register
F is the Flag register. (Its 8 bits are the different flags) It CAN be used
like a normal register though.
OOO! I was just thinking: Is it possible to just say ld f,0 to reset ALL
flags?
The Flags register (register F)
According to Assembly Studio 86:
The bits of the F register indicate the following:
Bit 0 C Carry flag – this flag is set if the previous addition or subtraction
instruction generated a carry/borrow.
Bit 1 N Add/Subtract flag – set if previous operation was a subtraction.
Bit 2 P/V Parity/Overflow flag
Bit 3 -- Not used
Bit 4 H Half-carry flag
Bit 5 -- Not used
Bit 6 Z Zero flag – set if previous instruction evaluated to zero.
Bit 7 S Sign flag – set if previous instruction produced a negative value.
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