Datasheet

Key Wakeups
MC68HC812A4 Data Sheet, Rev. 7
96 Freescale Semiconductor
9.2.6 Port H Data Direction Register
Read: Anytime
Write: Anytime
Data direction register H is associated with port H and designates each pin as an input or output.
DDRH7–DDRH0 — Data Direction Port H Bits
1 = Associated pin is an output.
0 = Associated pin is an input.
9.2.7 Port H Key Wakeup Interrupt Enable Register
An interrupt is generated when a bit in the KWIFH register and its corresponding KWIEH bit are both set.
These bits correspond to the pins of port H.
KWIEH7–KWIEH0 — Key Wakeup Port H Interrupt Enable Bits
1 = Interrupt for the associated bit is enabled.
0 = Interrupt for the associated bit is disabled.
9.2.8 Port H Key Wakeup Flag Register
Read: Anytime
Write: Anytime
Each flag is set by a falling edge on its associated input pin. To clear the flag, write one to the
corresponding bit in KWIFH.
KWIFH7–KWIFH0 — Key Wakeup Port H Flags
1 = Falling edge on the associated bit has occurred (an interrupt occurs if the associated enable bit
is set)
0 = Falling edge on the associated bit has not occurred
Address: $0025
Bit 7654321Bit 0
Read:
DDRH7 DDRH6 DDRH5 DDRH4 DDRH3 DDRH2 DDRH1 DDRH0
Write:
Reset:00000000
Figure 9-6. Port H Data Direction Register (DDRH)
Address: $0026
Bit 7654321Bit 0
Read:
KWIEH7 KWIEH6 KWIEH5 KWIEH4 KWIEH3 KWIEH2 KWIEH1 KWIEH0
Write:
Reset:00000000
Figure 9-7. Port H Key Wakeup Interrupt Enable Register (KWIEH)
Address: $0027
Bit 7654321Bit 0
Read:
KWIFH7 KWIFH6 KWIFH5 KWIFH4 KWIFH3 KWIFH2 KWIFH1 KWIFH0
Write:
Reset:00000000
Figure 9-8. Port H Key Wakeup Flag Register (KWIFH)