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Something unclear about PS/2 keyboard documentation
https://forum.osdev.org/viewtopic.php?f=1&t=32435		 Page 1 of 1
Author:  Ankeraout [ Thu Sep 21, 2017 11:52 pm ]
Post subject:  Something unclear about PS/2 keyboard documentation
Hello,

I am currently developing my PS/2 keyboard driver, and having some troubles with "ACK" signal wait etc...
So in the wiki, we can read this : Image

To me, it means that the keyboard will send "ACK" only after having sent the command byte AND the data byte.

Using QEMU, I've been receiving an ACK for keyboard reset command, then an ACK for 0xED, and then an ACK for LED states data byte, and so I'm lost and don't know how it should normally behave.

Thanks by advance,
Ankeraout.
Author:  Sik [ Fri Sep 22, 2017 12:13 am ]
Post subject:  Re: Something unclear about PS/2 keyboard documentation
Going by memory, but I think you do indeed get an ACK for each byte. In fact, you need to wait for the first ACK before you send the second byte (the ACK is the keyboard telling you that it just processed the byte).
Author:  Ankeraout [ Fri Sep 22, 2017 5:52 am ]
Post subject:  Re: Something unclear about PS/2 keyboard documentation
I can confirm that for every byte we send to the keyboard, he will reply with an ACK.
Thank you !
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