mc68hc908gr8vp Freescale Semiconductor, Inc, mc68hc908gr8vp Datasheet - Page 239

• Manufacturer Part Number: mc68hc908gr8vp
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

TOF — TIM Overflow Flag Bit
TOIE — TIM Overflow Interrupt Enable Bit
TSTOP — TIM Stop Bit
TRST — TIM Reset Bit
PS2–PS0 — Prescaler Select Bits
Freescale Semiconductor
This read/write flag is set when the TIM counter reaches the modulo value programmed in the TIM
counter modulo registers. Clear TOF by reading the TIM status and control register when TOF is set
and then writing a 0 to TOF. If another TIM 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.
This read/write bit enables TIM overflow interrupts when the TOF bit becomes set. Reset clears the
TOIE bit.
This read/write bit stops the TIM counter. Counting resumes when TSTOP is cleared. Reset sets the
TSTOP bit, stopping the TIM counter until software clears the TSTOP bit.
Setting this write-only bit resets the TIM counter and the TIM prescaler. Setting TRST has no effect on
any other registers. Counting resumes from $0000. TRST is cleared automatically after the TIM
counter is reset and always reads as logic 0. Reset clears the TRST bit.
These read/write bits select either the TCLK pin or one of the seven prescaler outputs as the input to
the TIM counter as
1 = TIM counter has reached modulo value
0 = TIM counter has not reached modulo value
1 = TIM overflow interrupts enabled
0 = TIM overflow interrupts disabled
1 = TIM counter stopped
0 = TIM counter active
1 = Prescaler and TIM counter cleared
0 = No effect
Address:
Do not set the TSTOP bit before entering wait mode if the TIM 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.
Setting the TSTOP and TRST bits simultaneously stops the TIM counter at
a value of $0000.
Reset:
Read:
Write:
T1SC, $0020 and T2SC, $002B
Table 22-2
Bit 7
TOF
Figure 22-4. TIM Status and Control Register (TSC)
0
0
MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7
= Unimplemented
TOIE
6
0
shows. Reset clears the PS[2:0] bits.
TSTOP
5
1
NOTE
NOTE
TRST
4
0
0
3
0
0
PS2
2
0
PS1
1
0
Bit 0
PS0
0
I/O Registers
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