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Hi,

I was wondering how the SF, ZF and PF flags are affected by the AND instruction, the intel docs say that they are set according to the result, but how are they set? what are the conditions?

Does ZF (Zero Flag) get set to zero if the result is zero and set to one if the result is non-zero? How are the other flags affected, I wish the docs were a bit more clear

Thanks.

The reason I want this is because in crazybuddah's ketboard handler he ANDs the scancode to test if it is a release so I just want to understand exactly what is happening. Also, does anyone have or know of where I can get a list of what comes to the handler when each key is pressed? For example, I know that a different set of codes come for the right and left alt,ctrl keys, it seems as though a special set come before the right keys are pressed.

Thanks.

ftp://ftp.simtel.net/pub/simtelnet/msdos/info/helppc21.zip

Contains a great deal of information about these kinds of things. It's a fairly indispensable reference tool for people working in assembler on x86 architecture.

Curufir