MC908GR32AVFAE Datasheet, PDF (234/314 Pages) Freescale Semiconductor, Inc – Microcontrollers

Timer Interface Module (TIM1)
Address: $0020
Bit 7
6
5
4
3
Read: TOF
0
0
TOIE TSTOP
Write: 0
TRST
Reset: 0
0
1
0
0
= Unimplemented
2
1
Bit 0
PS2
PS1
PS0
0
0
0
Figure 17-5. TIM1 Status and Control Register (T1SC)
TOF — TIM1 Overflow Flag Bit
This read/write flag is set when the TIM1 counter reaches the modulo value programmed in the TIM1
counter modulo registers. Clear TOF by reading the TIM1 status and control register when TOF is set
and then writing a 0 to TOF. If another TIM1 overflow occurs before the clearing sequence is complete,
then writing 0 to TOF has no effect. Therefore, a TOF interrupt request cannot be lost due to
inadvertent clearing of TOF. Reset clears the TOF bit. Writing a 1 to TOF has no effect.
1 = TIM1 counter has reached modulo value
0 = TIM1 counter has not reached modulo value
TOIE — TIM1 Overflow Interrupt Enable Bit
This read/write bit enables TIM1 overflow interrupts when the TOF bit becomes set. Reset clears the
TOIE bit.
1 = TIM1 overflow interrupts enabled
0 = TIM1 overflow interrupts disabled
TSTOP — TIM1 Stop Bit
This read/write bit stops the TIM1 counter. Counting resumes when TSTOP is cleared. Reset sets the
TSTOP bit, stopping the TIM1 counter until software clears the TSTOP bit.
1 = TIM1 counter stopped
0 = TIM1 counter active
NOTE
Do not set the TSTOP bit before entering wait mode if the TIM1 is required
to exit wait mode. Also, when the TSTOP bit is set and the timer is
configured for input capture operation, input captures are inhibited until the
TSTOP bit is cleared.
TRST — TIM1 Reset Bit
Setting this write-only bit resets the TIM1 counter and the TIM1 prescaler. Setting TRST has no effect
on any other registers. Counting resumes from $0000. TRST is cleared automatically after the TIM1
counter is reset and always reads as 0. Reset clears the TRST bit.
1 = Prescaler and TIM1 counter cleared
0 = No effect
NOTE
Setting the TSTOP and TRST bits simultaneously stops the TIM1 counter
at a value of $0000.
MC68HC908GR60A • MC68HC908GR48A • MC68HC908GR32A Data Sheet, Rev. 5
234
Freescale Semiconductor