What are the polarity values in Ubuntu 16.04

I don’t know if I’m on the right track, but this is what I’ve done:

I’ve used the this script https://github.com/RobertCNelson/boot-scripts/blob/master/tools/eMMC/init-eMMC-flasher-v3.sh to flash my bbb. I’ve found the bone_capemgr under /sys/devices/platform and I was able to export a pwm port, I think. ( echo BB-PWM0 > /sys/devices/platform/bone_capemgr/slots and later echo 0 > /sys/class/pwm/export)
I see the directory with:

duty_cycle enable period polarity power uevent


when I cat polarity I get: normal.

My question(s) is(are):

  • Can I use ubuntu 16.04 on the bbb?

  • What are the other values for polarity?

Any help is much appreciated.

Cheers, Gijs

Hi Gijs,

We’re using Ubuntu 16.04 on our BBB based midi controller - and that saves about 30 seconds on the boot time and the system is generally much better behaving than under 14.04.
The image I use for flashing are from : http://elinux.org/BeagleBoardUbuntu - basically using an SDCard with the flasher to flash.

I use an a bit of code in my apps to change the polarity - but basically it comes down to entering a 0 or 1 into the gpioXX/active_low

I’ve recently modified the simpleGPIO lib from Derek Molloy to include this code over the past weeks for a small project.