BBG PWM issue

Products & Technology BeagleBone
#1

Hi,
I am using BBGs’ PWM, and I found the frequency and the duty of the PWM can’t set precision.
eg, If you set the freq of the PWM to 20kHz, you will get a 19.9kHz wave form.
if the freq set to 10MHz, you will get a 9.1MHz wave form.
And , if the freq is set to 10MHz, even if you set the duty to 50%, you will get a 55% duty.
I hope you can check it , thank you!

Best regards,

Zhang

#2

Hi Zhang,

I double checked with hardware and software engineer that it is related with the software driver.

Here is the driver.
https://github.com/beagleboard/linux/blob/4.19/drivers/pwm/pwm-tiehrpwm.c

I see you already posted the issue on the github. So please follow up with github. Thanks.

best rgds
Bill
#3

Hi Zhang,





I double checked with hardware and software engineer that it is related with the software driver.





Here is the driver.

<LINK_TEXT text=“https://github.com/beagleboard/linux/bl … tiehrpwm.c”>https://github.com/beagleboard/linux/blob/4.19/drivers/pwm/pwm-tiehrpwm.c</LINK_TEXT>







I see you already posted the issue on the github. So please follow up with github. Thanks.

best rgds

Bill