Multifunction Timer Module
I/O Registers
MC68HC705KJ1MC68HRC705KJ1MC68HLC705KJ1 — Rev. 3.0
Technical Data
MOTOROLA
Multifunction Timer Module
111
TOF — Timer Overflow Flag
This read-only flag becomes set when the first eight stages of the
counter roll over from $FF to $00. TOF generates a timer overflow
interrupt request if TOIE is also set. Clear TOF by writing a logic 1 to
the TOFR bit. Writing to TOF has no effect. Reset clears TOF.
RTIF — Real-Time Interrupt Flag
This read-only flag becomes set when the selected RTI output
becomes active. RTIF generates a real-time interrupt request if RTIE
is also set. Clear RTIF by writing a logic 1 to the RTIFR bit. Writing
to RTIF has no effect. Reset clears RTIF.
TOIE — Timer Overflow Interrupt Enable Bit
This read/write bit enables timer overflow interrupts. Reset clears
TOIE.
1 = Timer overflow interrupts enabled
0 = Timer overflow interrupts disabled
RTIE — Real-Time Interrupt Enable Bit
This read/write bit enables real-time interrupts. Reset clears RTIE.
1 = Real-time interrupts enabled
0 = Real-time interrupts disabled
TOFR — Timer Overflow Flag Reset Bit
Writing a logic 1 to this write-only bit clears the TOF bit. TOFR always
reads as logic 0. Reset clears TOFR.
RTIFR — Real-Time Interrupt Flag Reset Bit
Writing a logic 1 to this write-only bit clears the RTIF bit. RTIFR
always reads as logic 0. Reset clears RTIFR.
RT1 and RT0 — Real-Time Interrupt Select Bits
These read/write bits select one of four real-time interrupt rates, as
shown in Table 10-2. Because the selected RTI output drives the
COP watchdog, changing the real-time interrupt rate also changes
the counting rate of the COP watchdog. Reset sets RT1 and RT0.
NOTE:
Changing RT1 and RT0 when a COP timeout is imminent can cause a
real-time interrupt request to be missed or an additional real-time