LPC47M172 SMSC Corporation, LPC47M172 Datasheet - Page 115

• Manufacturer Part Number: LPC47M172
• Description: ADVANCED I/O CONTROLLER WITH MOTHERBOARD GLUE LOGIC
• Manufacturer: SMSC Corporation

7.25
7.25.1 Keyboard Interface
Note 1:
SMSC LPC47M172
8042 Keyboard Controller Description
The LPC47M172 is a Super I/O and Universal Keyboard Controller that is designed for intelligent keyboard
management in desktop computer applications. The Universal Keyboard Controller uses an 8042
microcontroller CPU core. This section concentrates on the LPC47M172 enhancements to the 8042. For
general information about the 8042, refer to the “Hardware Description of the 8042” in the 8-Bit Embedded
Controller Handbook.
KIRQ is the Keyboard IRQ
MIRQ is the Mouse IRQ
Port 21 is used to create a GATEA20 signal from the LPC47M172.
The LPC47M172 LPC interface is functionally compatible with the 8042 style host interface. It consists of
the D0-7 data signals; the read and write signals and the Status register, Input Data register, and Output
Data register. Table 7.10 shows how the interface decodes the control signals. In addition to the above
signals, the host interface includes keyboard and mouse IRQs.
These registers consist of three separate 8 bit registers. Status, Data/Command Write and Data Read.
ADDRESS
0x60
0x64
8042A
TST0
TST1
COMMAND
P27
P10
P26
P23
P22
P11
Read
Read
Write
Write
Keyboard and Mouse Interface
Table 7.10 - I/O Address Map
DATASHEET
BLOCK
KDATA
KDATA
KDCTL
KDCTL
Page 115
LS05
Keyboard Data Write (C/D=0)
Keyboard Data Read
Keyboard Command Write (C/D=1)
Keyboard Status Read
FUNCTION (NOTE 1)
Advanced I/O Controller with Motherboard GLUE Logic
SMSC/Non-SMSC Register Sets (Rev. 02-27-04)
KDAT
KCLK
MCLK
MDAT
Datasheet