MC908AZ32ACFUE Datasheet, PDF (241/324 Pages) Freescale Semiconductor, Inc – Microcontrollers

I/O Registers
ACKK — Keyboard Acknowledge Bit
Writing a logic 1 to this write-only bit clears the keyboard interrupt request. ACKK always reads as logic
0. Reset clears ACKK.
IMASKK — Keyboard Interrupt Mask Bit
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.
1 = Keyboard interrupt requests masked
0 = Keyboard interrupt requests not masked
MODEK — Keyboard Triggering Sensitivity Bit
This read/write bit controls the triggering sensitivity of the keyboard interrupt pins. Reset clears
MODEK.
1 = Keyboard interrupt requests on falling edges and low levels
0 = Keyboard interrupt requests on falling edges only
22.7.2 Keyboard Interrupt Enable Register
The keyboard interrupt enable register enables or disables each port G and each port H pin to operate as
a keyboard interrupt pin.
Address: $0021
Bit 7
6
5
4
3
2
1
Read: 0
0
0
KBIE4 KBIE3 KBIE2 KBIE1
Write:
Reset: 0
0
0
0
0
0
0
= Unimplemented
Figure 22-4. Keyboard Interrupt Enable Register (KBIER)
Bit 0
KBIE0
0
KBIE4–KBIE0 — Keyboard Interrupt Enable Bits
Each of these read/write bits enables the corresponding keyboard interrupt pin to latch interrupt
requests. Reset clears the keyboard interrupt enable register.
1 = PDx pin enabled as keyboard interrupt pin
0 = PDx pin not enabled as keyboard interrupt pin
MC68HC908AZ32A Data Sheet, Rev. 2
Freescale Semiconductor
241