Z8F1680SH020SG Datasheet, PDF (126/412 Pages) Zilog, Inc. – High-Performance 8-Bit Microcontrollers

Z8 Encore! XP^® F1680 Series
Product Specification
101
COMPARE Mode Time (s)
=
_{---C----o---m-----p---a--r--e----V-----a--l--u---e---------S---t--a--r--t----V----a---l-u---e---}_----_{-----P---r--e---s--c---a--l--e-}
Timer Clock Frequency (Hz)
generated the interrupt, read the associated GPIO input value and compare to the value
stored in the TPOL bit.
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 timer clock. When 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 (assuming the Timer Input signal is still asserted).
Also, if the Timer Output alternate function is enabled, the Timer Output pin changes state
(from Low to High or from High to Low) at timer reset.
Observe the following steps to configure a timer for GATED Mode and initiate the count:
1. Write to the Timer Control 1 Register to:
– Disable the timer
– Configure the timer for GATED Mode
– Set the prescale value
2. Write to the Timer Control 2 Register to choose the timer clock source.
3. Write to the Timer Control 0 Register to set the timer interrupt configuration field
TICONFIG.
4. Write to the Timer High and Low Byte registers to set the starting count value. This
value only affects the first pass in GATED Mode. After the first timer reset in GATED
Mode, counting always begins at the reset value of 0001H.
5. Write to the Timer Reload High and Low Byte registers to set the reload value.
6. If required, enable the timer interrupt and set the timer interrupt priority by writing to
the relevant interrupt registers. By default, the timer interrupt will be generated for
both input deassertion and reload events. If required, configure the timer interrupt to
be generated only at the Input Deassertion event or the Reload event by setting
TICONFIG field of the Timer Control 0 Register.
7. Configure the associated GPIO port pin for the Timer Input alternate function.
8. Write to the Timer Control 1 Register to enable the timer.
9. Assert the Timer Input signal to initiate the counting.
PS025015-1212
PRELIMINARY
Timers