MC68HC908AS60ACFN FREESCALE [Freescale Semiconductor, Inc], MC68HC908AS60ACFN Datasheet - Page 305

• Manufacturer Part Number: MC68HC908AS60ACFN
• Description: M68HC08 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

24.7.1 Keyboard Status and Control Register
The keyboard status and control register:
Bits 7–4 — Not used
KEYF — Keyboard Flag Bit
ACKK — Keyboard Acknowledge Bit
IMASKK — Keyboard Interrupt Mask Bit
MODEK — Keyboard Triggering Sensitivity Bit
Freescale Semiconductor
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These read-only bits always read as logic 0s.
This read-only bit is set when a keyboard interrupt is pending. Reset clears the KEYF bit.
Writing a logic 1 to this write-only bit clears the keyboard interrupt request. ACKK always reads as logic
0. Reset clears ACKK.
Writing a logic 1 to this read/write bit prevents the output of the keyboard interrupt mask from
generating interrupt requests. Reset clears the IMASKK bit.
This read/write bit controls the triggering sensitivity of the keyboard interrupt pins. Reset clears
MODEK.
1 = Keyboard interrupt pending
0 = No keyboard interrupt pending
1 = Keyboard interrupt requests masked
0 = Keyboard interrupt requests not masked
1 = Keyboard interrupt requests on falling edges and low levels
0 = Keyboard interrupt requests on falling edges only
Flags keyboard interrupt requests
Acknowledges keyboard interrupt requests
Masks keyboard interrupt requests
Controls keyboard interrupt triggering sensitivity
Address: $001B
Reset:
Read:
Write:
MC68HC908AZ60A • MC68HC908AS60A • MC68HC908AS60E Data Sheet, Rev. 6
Figure 24-3. Keyboard Status and Control Register (KBSCR)
Bit 7
0
0
= Unimplemented
6
0
0
5
0
0
4
0
0
KEYF
3
0
ACKK
2
0
0
IMASKK
1
0
MODEK
Bit 0
0
I/O Registers
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