MC68HC908JK1 Datasheet, PDF (166/210 Pages) Motorola, Inc – MC68HC908JK1

Keyboard Interrupt Module (KBI)
Addr. Register Name
Bit 7
6
5
4
3
Read: 0
0
0
0
KEYF
Keyboard Status
$001A
and Control Register Write:
(KBSCR)
Reset: 0
0
0
0
0
Read: 0
$001B
Keyboard Interrupt Enable
Register (KBIER)
Write:
Reset: 0
KBIE6 KBIE5 KBIE4 KBIE3
0
0
0
0
= Unimplemented
Figure 14-1. KBI I/O Register Summary
2
0
ACKK
0
1
Bit 0
IMASKK MODEK
0
0
KBIE2 KBIE1 KBIE0
0
0
0
14.4 Functional Description
INTERNAL BUS
KBI0
.
KBIE0
.
TO PULLUP ENABLE
.
KBI6
KBIE6
TO PULLUP ENABLE
Technical Data
166
V_DD
D ^CLR Q
CK
ACKK
RESET
KEYBOARD
INTERRUPT FF
VECTOR FETCH
DECODER
KEYF
SYNCHRONIZER
Keyboard
Interrupt
Request
IMASKK
MODEK
Figure 14-2. Keyboard Interrupt Block Diagram
Writing to the KBIE6–KBIE0 bits in the keyboard interrupt enable register
independently enables or disables each port A pin as a keyboard
interrupt pin. Enabling a keyboard interrupt pin in port A also enables its
internal pull-up device irrespective of PTAPUEx bits in the port A input
pull-up enable register (see 12.4.2). A logic 0 applied to an enabled
keyboard interrupt pin latches a keyboard interrupt request.
Keyboard Interrupt Module (KBI)
MC68H(R)C908JL3 — Rev. 1.0
MOTOROLA