PWM pins and channels

Autonomous Machines Jetson & Embedded Systems Jetson Nano
1

Hello,

Are there hardware PWMs in Jetson Nano? If so, where are they physically routed to in the board?

After looking for info on this it seems officialy Jetson.GPIO does not support hardware/software PWM, and that is clear from the documentation and various other forums. However, when accessing /sys/class/pwm/ there are pwmchip0 (with 4 channels) and pwmchip4 (with 1 channel).

After looking at this, I was playing with python-periphery library (https://github.com/vsergeev/python-periphery) which is used in other embedded platforms. After trying a little, all channels and pins seemed to be “busy” (this was the error message displayed by python-periphery) with the exception of pin 0 channel 2, for which I did not get any error message. The issue is however that, after measuring all pins with an oscilloscope, I could not find which physical pin in the output headers was it routed to.

If this functionality is available but as of now there is no official support, could you please let me know which steps could one follow to use the pwm devices in /sys/class/pwm?

Thanks!

2

Hi, below three PWM pins are routed out:

Pin 206, PWM0
Pin 228, PWM2
Pin 230, PWM3

For how to configure them, please refer to this: [url]https://elinux.org/Jetson/PWM[/url] and this topic: [url]https://devtalk.nvidia.com/default/topic/899535[/url]

3

Thanks! By the way, is there any documentation on the routing of these pins I can refer to?

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