8042 KEYBOARD CONTROLLER DESCRIPTION
The LPC47B27x 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 LPC47B27x enhancements to the 8042. For general information about the 8042, refer to the "Hard-
ware Description of the 8042" in the 8-Bit Embedded Controller Handbook
8042A
LS05
P27
KDAT
KCLK
MCLK
MDAT
P10
P26
TST0
P23
TST1
P22
P11
Keyboard and Mouse Interface
KIRQ is the Keyboard IRQ
MIRQ is the Mouse IRQ
Port 21 is used to create a GATEA20 signal from the LPC47B27x.
KEYBOARD INTERFACE
The LPC47B27x 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 51 shows how the interface decodes the control signals. In addition to the above
signals, the host interface includes keyboard and mouse IRQs.
Table 51 - I/O Address Map
ADDRESS
0x60
Comman
d
BLOCK
FUNCTION (NOTE 1)
Write
Read
Write
Read
KDATA
KDATA
KDCTL
KDCTL
Keyboard Data Write (C/D=0)
Keyboard Data Read
Keyboard Command Write (C/D=1)
Keyboard Status Read
0x64
Note 1: These registers consist of three separate 8 bit registers. Status, Data/Command Write and Data
Read.
SMSC LPC47B27x
- 100 -
Rev. 08-10-04
DATASHEET
SMSC [ SMSC CORPORATION ]
