w83977ctf Winbond Electronics Corp America, w83977ctf Datasheet - Page 88

• Manufacturer Part Number: w83977ctf
• Description: Winbond I/o
• Manufacturer: Winbond Electronics Corp America

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
0
1
2
3
4
5
6
7
Output Buffer Full
Input Buffer Full
System Flag
Command/Data
Inhibit Switch
Auxiliary Device Output
Buffer
General Purpose Time-
out
Parity Error
BIT FUNCTION
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 writing to the system flag
bit in the command byte of the keyboard controller. It
defaults to 0 after a power-on reset.
0: Data byte
1: Command byte
0: Keyboard is inhibited
1: Keyboard is not inhibited
0: Auxiliary device output buffer empty
1: Auxiliary device output buffer full
0: No time-out error
1: Time-out error
0: Odd parity
1: Even parity (error)
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DESCRIPTION
Publication Release Date: March 1999
W83977EF/ CTF
PRELIMINARY
Revision A1