S908QC16CDRE FREESCALE [Freescale Semiconductor, Inc], S908QC16CDRE Datasheet - Page 85

• Manufacturer Part Number: S908QC16CDRE
• Description: Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Chapter 8
Keyboard Interrupt Module (KBI)
8.1 Introduction
The keyboard interrupt module (KBI) provides independently maskable external interrupts. The KBI
shares its pins with general-purpose input/output (I/O) port pins. See
shared pins.
8.2 Features
Features of the keyboard interrupt module include:
8.3 Functional Description
The keyboard interrupt module controls the enabling/disabling of interrupt functions on the KBI pins.
These pins can be enabled/disabled independently of each other.
Freescale Semiconductor
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Keyboard interrupt pins with separate keyboard interrupt enable bits and one keyboard interrupt
mask
Programmable edge-only or edge and level interrupt sensitivity
Edge sensitivity programmable for rising or falling edge
Level sensitivity programmable for high or low level
Pullup or pulldown device automatically enabled based on the polarity of edge or level detect
Exit from low-power modes
KBI0
KBIx
KBIP0
KBIPx
1
0
1
0
VECTOR FETCH
INTERNAL BUS
S
S
DECODER
MC68HC908QC16 • MC68HC908QC8 • MC68HC908QC4 Data Sheet, Rev. 2
KBIE0
TO PULLUP/
PULLDOWN ENABLE
TO PULLUP/
PULLDOWN ENABLE
KBIEx
Figure 8-1. Keyboard Interrupt Block Diagram
RESET
ACKK
MODEK
V
DD
KBI LATCH
D
CK
CLR
Q
Figure 8-2
IMASKK
SYNCHRONIZER
for port location of these
KEYF
KEYBOARD
INTERRUPT
REQUEST
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