Datasheet

Auto Wakeup Module (AWU)
MC68HC908QB8 Data Sheet, Rev. 3
54 Freescale Semiconductor
4.6.2 Keyboard Status and Control Register
The keyboard status and control register (KBSCR):
• Flags keyboard/auto wakeup interrupt requests
• Acknowledges keyboard/auto wakeup interrupt requests
• Masks keyboard/auto wakeup interrupt requests
Bits 7–4 — Not used
These read-only bits always read as 0s.
KEYF — Keyboard Flag Bit
This read-only bit is set when a keyboard interrupt is pending on port A or auto wakeup. Reset clears
the KEYF bit.
1 = Keyboard/auto wakeup interrupt pending
0 = No keyboard/auto wakeup interrupt pending
ACKK — Keyboard Acknowledge Bit
Writing a 1 to this write-only bit clears the keyboard/auto wakeup interrupt request on port A and auto
wakeup logic. ACKK always reads as 0. Reset clears ACKK.
IMASKK— Keyboard Interrupt Mask Bit
Writing a 1 to this read/write bit prevents the output of the keyboard interrupt mask from generating
interrupt requests on port A or auto wakeup. Reset clears the IMASKK bit.
1 = Keyboard/auto wakeup interrupt requests masked
0 = Keyboard/auto wakeup interrupt requests not masked
NOTE
MODEK is not used in conjuction with the auto wakeup feature. To see a
description of this bit, see 9.8.1 Keyboard Status and Control Register
(KBSCR).
4.6.3 Keyboard Interrupt Enable Register
The keyboard interrupt enable register (KBIER) enables or disables the auto wakeup to operate as a
keyboard/auto wakeup interrupt input.
Bit 7654321Bit 0
Read:0000KEYF 0
IMASKK MODEK
Write:
ACKK
Reset:00000000
= Unimplemented
Figure 4-3. Keyboard Status and Control Register (KBSCR)
Bit 7654321Bit 0
Read: 0
AWUIE KBIE5 KBIE4 KBIE3 KBIE2 KBIE1 KBIE0
Write:
Reset:00000000
= Unimplemented
Figure 4-4. Keyboard Interrupt Enable Register (KBIER)