W83C43 Datasheet, PDF (8/21 Pages) Winbond – KEYBOARD CONTROLLER

W83C43
(A) Input Port Definition (AT Mode), continued
BIT
FUNCTION
5
Manufacturing Jumper Installed
0: Manufacturing jumper
1: Jumper not installed
6
Display Type Switch
0: Primary display attached to color/graphics
1: Primary display attached to monochrome
7
Keyboard Inhibit Switch
0: Keyboard inhibited
1: Keyboard not inhibited
(B) Output Port Definition (AT Mode)
BIT
0
System Reset
1
Gate A20
2
Undefined
3
Undefined
4
Output Buffer Full
5
Input Buffer Empty
6
Keyboard Clock (Output)
7
Keyboard Data (Output)
FUNCTION
(C) Test-input Port Definition (AT Mode)
BIT
0
Keyboard Clock (Input)
1
Keyboard Data (Input)
FUNCTION
Status Register (PS/2 Mode)
BIT
BIT FUNCTION
0
Output Buffer Full
1
Input Buffer Full
2
System Flag
DESCRIPTION
0: Output buffer empty
1: Output buffer full
0: Input buffer empty
1: Input buffer full
This bit may be set to 0 or 1 by writting to the system flag
bit in the command byte of the keyboard controller. It is
set to 0 after a power-on reset.
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