Operation Of Tom In Pwm Output Mode - Mitsubishi 32172 User Manual

INPUT/OUTPUT TIMERS
10
10.6 TOM (Output Related 16-bit Timers)

10.6.13 Operation of TOM in PWM Output Mode

(1) Outline of PWM Output Mode for TOM
In PWM output mode, the TOM uses two reload registers to generate a waveform with any duty
cycle.
When the timer is enabled after setting the initial value in the reload 0 and the reload 1 registers,
the counter is loaded with the value of the reload 0 register synchronously with the count clock,
from which it starts counting down. The first time the counter underflows after reaching the
minimum count, it is loaded with the content of the reload 1 register. Thereafter, the counter is
alternately reloaded by the reload 0 and the reload 1 registers each time it underflows. The reload
0 register set value + 1 and the reload 1 register set value + 1 respectively are the valid count
values.
To stop the timer, write to the enable bit to disable counting, and the timer immediately stops (not
synchronized to the PWM output period).
The F/F output waveform in PWM output mode is inverted (F/F output changes level from low to
high or vice versa) when the counter starts counting and each time it underflows.
An interrupt and a DMA transfer request can be generated the second, the fourth, and other
even-numbered times the counter underflows after being enabled.
PWM output mode for TOM does not have a correction function.
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Rev.1.0