s908gr32ag3vfa Freescale Semiconductor, Inc, s908gr32ag3vfa Datasheet - Page 115

• Manufacturer Part Number: s908gr32ag3vfa
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

The KBIP7–KBIP0 bits determine the polarity of the keyboard pin detection. These bits along with the
MODEK bit determine whether a logic level (0 or 1) and/or a falling (or rising) edge is being detected.
Freescale Semiconductor
$001A
$001B
$0448
Addr.
•
•
KBD0
KBD7
KBIP0
KBIP7
If the keyboard interrupt is edge-sensitive only, a falling (or rising) edge on a keyboard pin does not
latch an interrupt request if another keyboard pin is already asserted. To prevent losing an interrupt
request on one pin because another pin is still asserted, software can disable the latter pin while it
is asserted.
If the keyboard interrupt is edge and level sensitive, an interrupt request is present as long as any
keyboard interrupt pin is asserted and the pin is keyboard interrupt enabled.
Keyboard Status and Control
Keyboard Interrupt Polarity
Keyboard Interrupt Enable
Register Name
Register (INTKBSCR)
Register (INTKBIER)
Register (INTKBIPR)
1
0
1
0
VECTOR FETCH
S
S
INTERNAL BUS
DECODER
See page 118.
See page 119.
See page 119.
MC68HC908GR60A • MC68HC908GR48A • MC68HC908GR32A Data Sheet, Rev. 5
TO PULLUP/
PULLDOWN ENABLE
TO PULLUP/
PULLDOWN ENABLE
KBIE0
KBIE7
Reset:
Reset:
Reset:
Figure 9-2. Keyboard Module Block Diagram
Read:
Read:
Read:
Write:
Write:
Write:
RESET
ACKK
Figure 9-3. I/O Register Summary
KBIE7
KBIP7
Bit 7
0
0
0
0
= Unimplemented
KBIE6
KBIP6
6
0
0
0
0
MODEK
V
DD
KBIE5
KBIP5
5
0
0
0
0
D
CK
CLR
Q
KBIE4
KBIP4
4
0
0
0
0
KBIE3
KBIP3
KEYF
3
0
0
0
IMASKK
SYNCHRONIZER
ACKK
KBIE2
KBIP2
2
0
0
0
0
Functional Description
IMASKK
KBIE1
KBIP1
KEYF
1
0
0
0
KEYBOARD
INTERRUPT
REQUEST
MODEK
KBIE0
KBIP0
Bit 0
0
0
0
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