W83977AF Information Storage Devices, Inc, W83977AF Datasheet - Page 117

• Manufacturer Part Number: W83977AF
• Description: W83877TF Plus Kbc, Cir, RTC
• Manufacturer: Information Storage Devices, Inc

7. KEYBOARD CONTROLLER
The KBC (8042 with licensed KB BIOS) circuit of W83977F/ AF is designed to provide the functions
needed to interface a CPU with a keyboard and/or a PS/2 mouse, and can be used with IBM
compatible personal computers or PS/2-based systems. The controller receives serial data from the
keyboard or PS/2 mouse, checks the parity of the data, and presents the data to the system as a byte
of data in its output buffer. Then, the controller will assert an interrupt to the system when data are
placed in its output buffer. The keyboard and PS/2 mouse are required to acknowledge all data
transmissions. No transmission should be sent to the keyboard or PS/2 mouse until an acknowledge
is received for the previous data byte.
Multiplex I/O PINS
GP I/O PINS
KINH
Keyboard and Mouse Interface
P17
P12~P16
8042
- 105 -
P25
P21
T0
P24
P20
P27
P10
P26
P23
T1
P22
P11
W83977F/ W83977AF
Publication Release Date:March 1998
MCLK
MDAT
KIRQ
MIRQ
KDAT
KCLK
GATEA20
KBRST
PRELIMINARY
Revision 0.58
-