mc68hc908qf4 Freescale Semiconductor, Inc, mc68hc908qf4 Datasheet - Page 84

• Manufacturer Part Number: mc68hc908qf4
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Keyboard Interrupt Module (KBI)
9.7 Input/Output Registers
9.7.1 Keyboard Status and Control Register
Data Sheet
84
To protect the latch during the break state, write a 0 to the BCFE bit. With BCFE
at 0 (its default state), writing to the keyboard acknowledge bit (ACKK) in the
keyboard status and control register during the break state has no effect.
The following I/O registers control and monitor operation of the keyboard interrupt
module:
The keyboard status and control register (KBSCR):
Bits 7–4 — Not used
KEYF — Keyboard Flag Bit
ACKK — Keyboard Acknowledge Bit
Address:
•
•
•
•
•
•
These read-only bits always read as 0s.
This read-only bit is set when a keyboard interrupt is pending on port A or auto
wakeup. Reset clears the KEYF bit.
Writing a 1 to this write-only bit clears the keyboard interrupt request on port A
and auto wakeup logic. ACKK always reads as 0. Reset clears ACKK.
Reset:
Read:
Write:
1 = Keyboard interrupt pending
0 = No keyboard interrupt pending
Keyboard interrupt status and control register (KBSCR)
Keyboard interrupt enable register (KBIER)
Flags keyboard interrupt requests
Acknowledges keyboard interrupt requests
Masks keyboard interrupt requests
Controls keyboard interrupt triggering sensitivity
Freescale Semiconductor, Inc.
Figure 9-4. Keyboard Status and Control Register (KBSCR)
For More Information On This Product,
$001A
Bit 7
0
0
Keyboard Interrupt Module (KBI)
Go to: www.freescale.com
= Unimplemented
6
0
0
5
0
0
4
0
0
KEYF
3
0
ACKK
MC68HC908QF4 — Rev. 1.0
2
0
0
IMASKK
1
0
MOTOROLA
MODEK
Bit 0
0