z8f083a ZiLOG Semiconductor, z8f083a Datasheet - Page 79

• Manufacturer Part Number: z8f083a
• Description: High-performance 8-bit Microcontrollers
• Manufacturer: ZiLOG Semiconductor

PS026308-1207
timer output to make a state change at a ONE-SHOT time-out (rather than a single cycle
pulse), first set the TPOL bit in the timer control register to the start value before enabling
ONE-SHOT mode. After starting the timer, set TPOL to the opposite bit value.
The steps for configuring a timer for ONE-SHOT mode and for initiating the count are as
follows:
1. Write to the timer control register to:
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
5. If using the timer output function, configure the associated GPIO port pin for the timer
6. Write to the timer control register to enable the timer and initiate counting.
In ONE-SHOT mode, the system clock always provides the timer input. The timer period
is given by the following equation:
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. The timer input is the system clock. On reaching the
reload value, the timer generates an interrupt, the count value in the timer high and low
byte registers is reset to
alternate function is enabled, the timer output pin changes state (from low to high or from
high to low) at timer reload.
The steps for configuring a timer for CONTINUOUS mode and for initiating the count are
as follows:
1. Write to the timer control register to:
One-Shot Mode Time-Out Period (s)
–
–
–
–
to the relevant interrupt registers.
output alternate function.
–
–
–
Disable the timer
Configure the timer for ONE-SHOT mode
Set the prescale value
Set the initial output level (high or low) if using the timer output alternate function
Disable the timer
Configure the timer for CONTINUOUS mode
Set the prescale value
0001H
and the counting resumes. Also, if the timer output
=
(
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Reload Value Start Value
System Clock Frequency (Hz)
Z8 Encore!
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Product Specification
®
)
F083A Series
×
Prescale
Timers
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