Hello alex,
Why the register of FTM_C4V increase?
When you configure the channel to the PWM function , this register store the match value the
PWM output, when the FTM counter (FTM_CNT) match the value of Cnv , refer to the different PWM mode
, there will be different result , for the detail information , please refer to this part :

For example :

Hope it helps
Have a great day,
Alice Yang
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