A20 Gate

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Peter
Posts: 13
Joined: Wed Jan 05, 2005 12:00 am

A20 Gate

Post by Peter »

Hey people,

I'm Dutch so try to answer simple.
My question is about the A20 gate. If you read port 0x64 and test it on bit 1 you will test if the keyboard-controller is ready. But what are you testing if you doing it on bit 2?

Thanks :D
new_world
Posts: 5
Joined: Wed Jan 05, 2005 12:00 am

Re: A20 Gate

Post by new_world »

If bit 2 isn't clear then the output buffer isn't empty. You must wait till bit 2 is clear, then the command is sent.
For A20 you must wait some time that A20 is *really* enabled.
Last edited by new_world on Wed Jan 05, 2005 12:00 am, edited 1 time in total.
Peter
Posts: 13
Joined: Wed Jan 05, 2005 12:00 am

Re: A20 Gate

Post by Peter »

Thanks new_world :-D
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