s908ab32ag0cfue Freescale Semiconductor, Inc, s908ab32ag0cfue Datasheet - Page 226

• Manufacturer Part Number: s908ab32ag0cfue
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Programmable Interrupt Timer (PIT)
Technical Data
226
NOTE:
NOTE:
POF — PIT Overflow Flag Bit
POIE — PIT Overflow Interrupt Enable Bit
PSTOP — PIT Stop Bit
Do not set the PSTOP bit before entering wait mode if the PIT is required
to exit wait mode.
PRST — PIT Reset Bit
Setting the PSTOP and PRST bits simultaneously stops the PIT counter
at a value of $0000.
This read/write flag is set when the PIT counter resets to $0000 after
reaching the modulo value programmed in the PIT counter modulo
registers. Clear POF by reading the PIT status and control register
when POF is set and then writing a logic zero to POF. If another PIT
overflow occurs before the clearing sequence is complete, then
writing logic zero to POF has no effect. Therefore, a POF interrupt
request cannot be lost due to inadvertent clearing of POF. Reset
clears the POF bit. Writing a logic one to POF has no effect.
This read/write bit enables PIT overflow interrupts when the POF bit
becomes set. Reset clears the POIE bit.
This read/write bit stops the PIT counter. Counting resumes when
PSTOP is cleared. Reset sets the PSTOP bit, stopping the PIT
counter until software clears the PSTOP bit.
Setting this write-only bit resets the PIT counter and the PIT prescaler.
Setting PRST has no effect on any other registers. Counting resumes
from $0000. PRST is cleared automatically after the PIT counter is
reset and always reads as logic zero. Reset clears the PRST bit.
1 = PIT counter has reached modulo value
0 = PIT counter has not reached modulo value
1 = PIT overflow interrupts enabled
0 = PIT overflow interrupts disabled
1 = PIT counter stopped
0 = PIT counter active
1 = Prescaler and PIT counter cleared
0 = No effect
Programmable Interrupt Timer (PIT)
MC68HC908AB32
Freescale Semiconductor
—
Rev. 1.1