Z8 Encore!® Motor Control Flash MCUs
Product Specification
96
d. If using the Timer Output alternate function, set the initial output level (High or
Low) via TPOL.
2. Write to the Timer High and Low Byte registers to set the starting count value (usually
0001h). This setting only affects the first pass in CONTINUOUS mode. After the first
timer reload in CONTINUOUS mode, counting begins at the reset value of 0001h.
3. Write to the Timer Reload High and Low Byte registers to set the reload period.
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 and initiate counting.
The timer period is calculated by the following equation:
Reload Value x Prescaler
Continuous Mode Time-Out Period(s) =
System Clock Frequency (Hz)
If an initial starting value other than 0001his loaded into the Timer High and Low Byte
registers, use the ONE-SHOT mode equation to determine the first time-out period.
Counter and Comparator Counter Modes
In COUNTER mode, the timer counts input transitions from a GPIO port pin. The Timer
Input is taken from the associated GPIO port pin. The TPOLbit in the Timer Control 1
Register selects whether the count occurs on the rising edge or the falling edge of the
Timer Input signal. In COUNTER mode, the prescaler is disabled.
The input frequency of the Timer Input signal must not exceed one-fourth the system
clock frequency.
Caution:
In COMPARATOR COUNTER mode, the timer counts output transitions from an analog
comparator output. Timer 0 takes its input from the output of the comparator. The TPOLbit
in the Timer Control 1 Register selects whether the count occurs on the rising edge or the
falling edge of the comparator output signal. In COMPARATOR COUNTER mode, the
prescaler is disabled.
The frequency of the comparator output signal must not exceed one-fourth the system
clock frequency.
Caution:
General-Purpose Timer
P R E L I M I N A R Y
PS024604-1005
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