Datasheet

Section 18 Keyboard Buffer Control Unit (PS2)
Rev. 3.00 Sep. 28, 2009 Page 568 of 910
REJ09B0350-0300
18.3.3 Keyboard Control Register H (KBCRH)
KBCRH indicates the operating status of the keyboard buffer control unit.
Bit Bit Name
Initial
Value R/W Description
7 KBIOE 0 R/W Keyboard In/Out Enable
Selects whether or not the keyboard buffer control unit
is used.
0: The keyboard buffer control unit is non-operational
(KCLK and KD signal pins have port functions)
1: The keyboard buffer control unit is enabled for
transmission and reception (KCLK and KD signal
pins are in the bus drive state)
6 KCLKI 1 R Keyboard Clock In
Monitors the KCLK I/O pin. This bit cannot be
modified.
0: KCLK I/O pin is low
1: KCLK I/O pin is high
5 KDI 1 R Keyboard Data In
Monitors the KDI I/O pin. This bit cannot be modified.
0: KD I/O pin is low
1: KD I/O pin is high
4 KBFSEL 1 R/W Keyboard Buffer Register Full Select
Selects whether the KBF bit is used as the keyboard
buffer register full flag or as the KCLK fall interrupt
flag. When KBF bit is used as the KCLK fall interrupt
flag, the KBE bit in KBCRL should be cleared to 0 to
disable reception.
0: KBF bit is used as KCLK fall interrupt flag
1: KBF bit is used as keyboard buffer register full flag