Datasheet

Section 18 Keyboard Buffer Control Unit (PS2)
Rev. 3.00 Sep. 28, 2009 Page 562 of 910
REJ09B0350-0300
KD
(PS2AD,
PS2BD,
PS2CD,
PS2DD)
KDI
Transmission
start
Transmit counter
nalue
KCLKI
KDO
KCLKO
Parity
Register counter value
KBI interrupt
KCI interrupt
KTI interrupt
KCLK
(PS2AC,
PS2BC,
PS2CC,
PS2DC)
[Legend]
KD: PS2 data I/O pin
KCLK: PS2 clock I/O pin
KBBR: Keyboard data buffer register
KBCRH: Keyboard control register H
KBCRL: Keyboard control register L
KBTR: Keyboard buffer transmit data register
KBCR1: Keyboard control register 1
KBCR2: Keyboard control register 2
KBBR
KBCRH
KBCRL
Bus interface
Internal
data bus
KBTR
KBCR1
KBCR2
Module data bus
Control
logic
Figure 18.1 Block Diagram of PS2