Datasheet

Keyboard Interrupt (KBI)
Functional Description
MC68HC908GR8 — Rev 4.0 Technical Data
MOTOROLA Keyboard Interrupt (KBI) 177
Figure 13-1. Keyboard Module Block Diagram
KB0IE
KB3IE
.
.
.
KEYBOARD
INTERRUPT
DQ
CK
CLR
VDD
MODEK
IMASKK
KEYBOARD
INTERRUPT FF
REQUEST
VECTOR FETCH
DECODER
ACKK
INTERNAL BUS
RESET
TO PULLUP
KBD3
KBD0
TO PULLUP
SYNCHRONIZER
KEYF
ENABLE
ENABLE
Addr.Register Name Bit 7654321Bit 0
$001A
Keyboard Status
and Control Register
(INTKBSCR)
Read: 0000KEYF0
IMASKK MODEK
Write:
ACKK
Reset:00000000
$001B
Keyboard Interrupt Enable
Register (INTKBIER)
Read:
KBIE3 KBIE2 KBIE1 KBIE0
Write:
Reset: 0000
= Unimplemented
Figure 13-2. I/O Register Summary
Frees
cale Semiconductor,
I
Freescale Semiconductor, Inc.
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