Kinetis FTM PWM support

[lucas_zhou]

Hi all,

     The FlexTimer module (FTM) is a two to eight channel timer that supports the generation of PWM signals.

     I have a question that the frequency of PWM can set in different value each channel?

     Thanks in advance,Lucas.

[JimDon]

Pedro is correct, but the real problem with what you want to do is that there is only one modulo counter per  module.

You set a register that causes a counter to reset at a certain count, so the overall period is determined by the clock/pre-scaler and the reset value in the modulo register. The PWM channels have a compare register that is compared to the counter value and set/reset the PWM outputs at counter reset and the compare value.

[lucas_zhou]

Hi Jim

Does it means i can use configure PWM outputs in different frequency in each channel if i configure compare register?

Thanks !!

[JimDon]

The compare register for each channel only set the duty cycle for that channel.

The single modulo register for the single counter determines the frequency,

[apanecatl · Accepted solution]

Hi Lucas, the Flextimer module has only 1 prescale factor selection register per module hence all channels will run at the same frequency

[lucas_zhou]

Hi Pedro

I get it ! Thank you!!