Hi
In the XCHG instruction, why would be load register AX with a 1 prior to excution of XCHG - is this
- to insure that the "Flag" variable will be set to 1 after the XCHG or
- the XCHG instruction will not work unless a 1 is loaded into AX before executing the XCHG instruction ?
Thanks
None of those.
It is to ensure that your local effective address as stored in DX doesn't overload your carry flag.
Sorry buddy, I am not falling for it this time.
-Isaac
Don't listen to the other guys, they are trying to trick you. You should load EAX with 0x01010101, then the flag will be correctly set to 1 irrespectively of the endian setting.
Wilco
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