Z8FMC16100 Series Flash MCU
Product Specification
95
c. Set the prescale value.
d. If using the Timer Output alternate function, set the initial output level (High or
Low) via the TPOLbit.
e. Set the INTERRUPT mode.
2. Write to the Timer High and Low Byte registers to set the starting count value.
3. Write to the Timer Reload High and Low Byte registers to set the reload value.
4. If appropriate, enable the timer interrupt and set the timer interrupt priority by writing
to the relevant interrupt registers.
5. If using the Timer Output function, configure the associated GPIO port pin for the
Timer Output alternate function.
6. Write to the Timer Control 1 Register to enable the timer. Counting does not start until
the appropriate input transition occurs.
The timer period is calculated by the following equation (Start Value is typically = 1):
(Reload Value – Start Value + 1) x Prescaler
Triggered One-Shot Mode Time-Out Period(s) =
System Clock Frequency (Hz)
The one-shot delay from input trigger to output includes the above-defined time-out
period, plus an additional delay of 2–3 system clock cycles, due to the synchronization of
the input trigger.
Note:
Continuous Mode
In CONTINUOUS mode, the timer counts up to the 16-bit reload value stored in the Timer
Reload High and Low Byte registers. After reaching the reload value, the timer generates
an interrupt, the count value in the Timer High and Low Byte registers is reset to 0001h,
and counting resumes. Also, if the Timer Output alternate function is enabled, the Timer
Output pin changes state (from Low to High or from High to Low) after timer reload.
The steps for configuring a timer for CONTINUOUS mode and initiating the count are as
follows:
1. Write to the Timer Control registers to:
a. Disable the timer.
b. Configure the timer for CONTINUOUS mode.
c. Set the prescale value.
PS024604-1005
P R E L I M I N A R Y
Timer Operating Modes
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