FUJITSU MB91F109 FR30 - Manual (Page 339)

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14.9 PWM Operation
14.9 PWM Operation
PWM operation outputs pulses continuously.
■ PWM Operation.
Upon detection of a start trigger, the PWM timer outputs pulses continuously.
The cycle of output pulses can be controlled by changing the PCSR value, and the duty ratio
can be controlled by changing the PDUT value.
After writing data to the PCSR, write to the PDUT.
When the external TRG input is selected for the start trigger, input pulses with a pulse width that
equals or exceeds the following minimum pulse width:
Pulse width: Two machine cycles or more
When pulses that do not satisfy the condition above are input, ensure that they are recognized
as effective pulses. Since this model has no filter function for external TRG input, add a filter to
the external input as required.
Figure 14.9-1 shows a timing chart for PWM operation performed while trigger restart is
disabled. Figure 14.9-2 shows a timing chart for PWM operation performed while trigger restart
is enabled.