I can’t configure GPIO pins (GPIO 12, 17 in my case) to work on PWM frequency.
I tried to use 2 libraries to write my python code: python-periphery and Adafruit_BBIO.
- Overlays didn’t work.
- I tried to use ‘config-pin’ and it was not recognised. In order to use ‘config-pin’ I had to install bb.org-overlays repo and run the installer which I can’t on beagleY-AI since I got this error: Error: this script: [./install.sh] is not supported to run under [aarch64]
- I tried to edit manually extlinux.conf file and add required overlays for required pins. It didn’t help either.
My question is: what do I do? I’m trying to power a small motor that would rotate a wheel for me.
For GPIO12/GPIO17 you need to load these two overlays:
k3-am67a-beagley-ai-pwm-ecap0-gpio12.dtbo k3-am67a-beagley-ai-pwm-ecap2-gpio17.dtbo
Open, /boot/firmware/extlinux/extlinux.conf and add:
fdtoverlays /overlays/k3-am67a-beagley-ai-pwm-ecap0-gpio12.dtbo /overlays/k3-am67a-beagley-ai-pwm-ecap2-gpio17.dtbo
To the menu option you are currently using…
label microSD (default)
kernel /Image
append console=ttyS2,115200n8 root=/dev/mmcblk1p2 ro rootfstype=ext4 rootwait net.ifnames=0 quiet
fdtdir /
fdt /ti/k3-am67a-beagley-ai.dtb
fdtoverlays /overlays/k3-am67a-beagley-ai-pwm-ecap0-gpio12.dtbo /overlays/k3-am67a-beagley-ai-pwm-ecap2-gpio17.dtbo
#initrd /initrd.img
voodoo@beagley-ai-83:~$ sudo beagle-version | grep UBOOT
UBOOT: Booted Device-Tree:[k3-am67a-beagley-ai.dts]
UBOOT: Loaded Overlay:[k3-am67a-beagley-ai-pwm-ecap0-gpio12.kernel]
UBOOT: Loaded Overlay:[k3-am67a-beagley-ai-pwm-ecap2-gpio17.kernel]
I have a helper script:
sudo beagle-pwm-export --pin gpio12
sudo beagle-pwm-export --pin gpio17
They end up here: /dev/hat/pwm/
voodoo@beagley-ai-83:~$ ls -lha /dev/hat/pwm/
total 0
drwxr-xr-x 2 root root 80 Jun 16 11:15 .
drwxr-xr-x 3 root root 140 Jun 16 10:34 ..
lrwxrwxrwx 1 root root 63 Jun 16 10:34 GPIO12 -> /sys/devices/platform/bus@f0000/23100000.pwm/pwm/pwmchip0/pwm0/
lrwxrwxrwx 1 root root 63 Jun 16 11:15 GPIO17 -> /sys/devices/platform/bus@f0000/23120000.pwm/pwm/pwmchip2/pwm0/
Regards,
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Thank you for your answer. The overlays you mentioned are meant only to receive pwm signal (ECAP module). I have wiring diagrams included. Which overlays I need to import here so I can know the chips and channels I need to operate on?
Thank you!
temp.drawio (1.0 МБ)
Here is the full list of pwm overlays I have on my board:
k3-am67a-beagley-ai-pwm-ecap0-gpio12.dtbo
k3-am67a-beagley-ai-pwm-ecap1-gpio16.dtbo
k3-am67a-beagley-ai-pwm-ecap1-gpio21.dtbo
k3-am67a-beagley-ai-pwm-ecap2-gpio17.dtbo
k3-am67a-beagley-ai-pwm-ecap2-gpio18.dtbo
k3-am67a-beagley-ai-pwm-epwm0-gpio12.dtbo
k3-am67a-beagley-ai-pwm-epwm0-gpio14.dtbo
k3-am67a-beagley-ai-pwm-epwm0-gpio15.dtbo
k3-am67a-beagley-ai-pwm-epwm0-gpio15-gpio12.dtbo
k3-am67a-beagley-ai-pwm-epwm0-gpio15-gpio14.dtbo
k3-am67a-beagley-ai-pwm-epwm0-gpio5.dtbo
k3-am67a-beagley-ai-pwm-epwm0-gpio5-gpio12.dtbo
k3-am67a-beagley-ai-pwm-epwm0-gpio5-gpio14.dtbo
k3-am67a-beagley-ai-pwm-epwm1-gpio13.dtbo
k3-am67a-beagley-ai-pwm-epwm1-gpio20.dtbo
k3-am67a-beagley-ai-pwm-epwm1-gpio21.dtbo
k3-am67a-beagley-ai-pwm-epwm1-gpio21-gpio13.dtbo
k3-am67a-beagley-ai-pwm-epwm1-gpio21-gpio20.dtbo
k3-am67a-beagley-ai-pwm-epwm1-gpio6.dtbo
k3-am67a-beagley-ai-pwm-epwm1-gpio6-gpio13.dtbo
k3-am67a-beagley-ai-pwm-epwm1-gpio6-gpio20.dtbo