I want to control the frequency of PWM accurately.

RE: I want to control the frequency of PWM accurately.

Karl Ylvisaker — Thu, 08 Apr 2021 07:56:47 GMT

[quote user="schosdas"]Thank you for your answer.[/quote]

No problem at all, I am happy to help!

[quote user="schosdas"]I succeeded in outputting the frequency through Prescaler and top_value of pwm_driver.[/quote]

I am glad to hear that you were able to achieve the desired frequency by my suggestion using the PWM driver :)

Please do not hesitate to open a new ticket if you should encounter any other issues or questions.

Good luck with your development!

Best regards,
Karl

RE: I want to control the frequency of PWM accurately.

schosdas — Thu, 08 Apr 2021 00:52:35 GMT

Thank you for your answer.
I succeeded in outputting the frequency through Prescaler and top_value of pwm_driver.

RE: I want to control the frequency of PWM accurately.

Karl Ylvisaker — Wed, 07 Apr 2021 12:37:03 GMT

Hello,

The PWM library only provides micro-second resolution of the output PWM.
The APP_PWM_DEFAULT_CONFIG_1CH takes the period_in_us argument to set the period.
This is why you are seeing a 100 kHz PWM when you provide it 10, and a 111 kHz PWM when you provide it 9.
1/0.00001 = 100 kHz, 1/0.000009 = 111 kHz.

If you need to control the period more accurately, you will have to use peripheral driver with the approach I described to you in your other ticket yesterday.

Best regards,
Karl