W83977ATF Datasheet, PDF (204/207 Pages) Winbond – WINBOND I/O

W83977ATF
PRELIMINARY
6.3 Status Register
The status register is an 8-bit read-only register at I/O address 64H (Default, PnP programmable I/O
address LD5-CR62 and LD5-CR63), that holds information about the status of the keyboard controller
and interface. It may be read at any time.
BIT
BIT FUNCTION
DESCRIPTION
0
Output Buffer Full
0: Output buffer empty
1: Output buffer full
1
Input Buffer Full
0: Input buffer empty
1: Input buffer full
2
System Flag
This bit may be set to 0 or 1 by writing to the system flag
bit in the command byte of the keyboard controller. It
defaults to 0 after a power-on reset.
3
Command/Data
0: Data byte
1: Command byte
4
Inhibit Switch
0: Keyboard is inhibited
1: Keyboard is not inhibited
5
Auxiliary Device Output 0: Auxiliary device output buffer empty
Buffer
1: Auxiliary device output buffer full
6
General Purpose Time- 0: No time-out error
out
1: Time-out error
7
Parity Error
0: Odd parity
1: Even parity (error)
6.4 Commands
COMMAND
20h
60h
FUNCTION
Read Command Byte of Keyboard Controller
Write Command Byte of Keyboard Controller
BIT
BIT DEFINITION
7 Reserved
6 IBM Keyboard Translate Mode
5 Disable Auxiliary Device
4 Disable Keyboard
3 Reserve
2 System Flag
1 Enable Auxiliary Interrupt
0 Enable Keyboard Interrupt
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Publication Release Date:April 1998
Revision 0.52