PWM pins are not working at a Beaglebone Black

[Savvas-Piperidis]

Board Name

Beaglebone Black

Steps

1. I installed am335x-eMMC-flasher-debian-11.7-iot-armhf-2023-09-02-4gb , from the official Beagleboard repository.
2. I Installed the Adafruit - Blinka library.
3. PWM pins are not working (although GPIO pins are operating normally)

Description

As I have already commented at the issue #240:
I installed Adafruit-Blinka, on a Beaglebone Black Rev. C board. The board was flashed with the am335x-eMMC-flasher-debian-11.7-iot-armhf-2023-09-02-4gb.img.xz Debian image, from the official BeagleBoard repository. For the moment, I have tested the digitalio and the pwmio libraries. The first works fine with the GPIOs. The second is not working. I used the example program from the library examples at Adafruit web page. I replaced the "D4" pin of the original program, with "P9_14", to activate this pin on BBB.

I got the following error message

tucer@BeagleBone:~/tests/Blinka$ sudo python3 PWM.py
[sudo] password for tucer:
Traceback (most recent call last):
File "/home/tucer/tests/Blinka/PWM.py", line 5, in
led = pwmio.PWMOut(board.P9_14, frequency=5000, duty_cycle=0)
File "/usr/local/lib/python3.9/dist-packages/adafruit_blinka/microcontroller/am335x/sysfs_pwmout.py", line 68, in init
self._open(pin, duty_cycle, frequency, variable_frequency)
File "/usr/local/lib/python3.9/dist-packages/adafruit_blinka/microcontroller/am335x/sysfs_pwmout.py", line 88, in _open
raise RuntimeError("No PWM channel found for this Pin")
RuntimeError: No PWM channel found for this Pin

I checked the #200, #201, #168 issues for BBB PWM outputs. I tried to do some debugging from the user space in a terminal but nothing worked!

Additional information

I have, also, posted the problem at the Beagleboard forum:

• PWM not working at a BBB with Debian Boolseye 11 and Adafruit Blinka library

There is more debugging information there and a lot of data about the file system and the library at my BBB Debian system.