topic Re: Kinetis FTM PWM support in Kinetis Microcontrollers

Kinetis FTM PWM support

lucas_zhou — Fri, 09 Nov 2012 04:39:41 GMT

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.

Re: Kinetis FTM PWM support

apanecatl — Fri, 09 Nov 2012 16:50:52 GMT

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

Re: Kinetis FTM PWM support

JimDon — Sun, 11 Nov 2012 04:58:17 GMT

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.

Re: Kinetis FTM PWM support

lucas_zhou — Mon, 12 Nov 2012 13:00:43 GMT

Hi Pedro

I get it ! Thank you!!

Re: Kinetis FTM PWM support

lucas_zhou — Mon, 12 Nov 2012 13:03:18 GMT

Hi Jim

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