, (, , , ) (- ) ( ).
PC . (enhanced) AT PS/2, 100 . 84- AT XT. XT AT , , AT . ( AT XT/AT). PS/2 AT , .
, , , . -. - . (typematic delay) (typematic rate) AT . 1 3 -.
USB ; , USB. USB . USB BIOS; .
AT PS/2
, KB-Data KB-Clock. +5 . (), . ( ) . 8.1. 5- DIN ( AT) mini-DIN (PS/2). +5 .
. 8.1. ( ) : AT PS/2
, , . , , , . .
|
|
8042 - , . 60h, -. - IRQ1, ( ). , -, , , . , .
. 8.2, , , , . . , . ( ) KB-Data KB-Clock, . KB-Clock 0- KB-Data, KB-Clock. KB-Clock. 8 , . KB-Clock, (Ack). 2 , -.
. 8.2. : ,
(. 8.2, ). KB-Clock 250 - ( ) . 11 KB-Clock. , . (9- ) - (10-) 11- (Ack). KB-Clock (60 ), . 20 , , -. , 15 , -, 2 0.
PC/XT 8042 , () , 18255. IRQ1, 60h. 7 6 61h . XT KB-Clock.