I have found the PWM user modules estimate the output period adding an Offset equal
to 1 clk cycle of your external clock.
Therefore the formula remains finally:

Tout= nºPERIOD*Tclk+1cycle_clk;

(Where nºPERIOD is the counter PERIOD, the number of clk input risng edges to calculate
the PWM output square wave period).

I have supposed it's due to a kind of precharge or setup time te PWM UM needs to charge again the values
in the counter or make the interrupts once the countdown is over.

I haven't find any statement about this in the PWM datasheet.

Anyone could confirm that theory or I'm wrong?

Thanks for all.

Hi,

Yes you are right. The actual period value is the value whatever you are entering in Period register + 1. It is also mentioned in the PWM UM datasheet.

Regards,

Kishore.

Hi,

The extra clock is to count down the PWM counter value from 1 to 0 when counting down.

The configuration tab shows the "Period" value which takes into account this extra clock. You can set the Period value depending upon this value displayed.

Regards,

dasg