Hello everyone, I have come across a problem on the BBK (Debian 8.2 , 2015-09-11 release) and would be very grateful for a bit of an explanation.
I need to work with the PWMs and therefore I have developed a little ugly script in order to work with config-pin.sh (https://github.com/cdsteinkuehler/beaglebone-universal-io) and then export the pwmchip. Down the line I'd like to to have the script running at start-up, prior to launching a executable. The cape-universaln overlay is applied. The script goes as follow : #!/bin/bash echo "Configuring pins" sudo sh -c '/home/debian/beaglebone-universal-io/config-pin P9.22 pwm' sudo sh -c '/home/debian/beaglebone-universal-io/config-pin P9.21 pwm' sudo sh -c '/home/debian/beaglebone-universal-io/config-pin P9.14 pwm' sudo sh -c '/home/debian/beaglebone-universal-io/config-pin P9.16 pwm' sudo sh -c '/home/debian/beaglebone-universal-io/config-pin P8.19 pwm' sudo sh -c '/home/debian/beaglebone-universal-io/config-pin P8.13 pwm' echo "Export pins" if sudo sh -c 'echo "0" > /sys/class/pwm/pwmchip0/export' ; then echo "pwmchip0:pwm0 exported" else echo "pwmchip0:pwm0 export failed" fi if sudo sh -c 'echo "1" > /sys/class/pwm/pwmchip0/export' ; then echo "pwmchip0:pwm1 exported" else echo "pwmchip0:pwm1 export failed" fi if sudo sh -c 'echo "0" > /sys/class/pwm/pwmchip1/export'; then echo "pwmchip1:pwm0 exported" else echo "pwmchip1:pwm0 export failed" fi if sudo sh -c 'echo "1" > /sys/class/pwm/pwmchip1/export' ; then echo "pwmchip1:pwm1 exported" else echo "pwmchip1:pwm1 export failed" fi if sudo sh -c 'echo "0" > /sys/class/pwm/pwmchip2/export'; then echo "pwmchip2:pwm0 exported" else echo "pwmchip2:pwm0 export failed" fi if sudo sh -c 'echo "1" > /sys/class/pwm/pwmchip2/export'; then echo "pwmchip2:pwm1 exported" else echo "pwmchip2:pwm1 export failed" fi if sudo sh -c 'echo "0" > /sys/class/pwm/pwmchip4/export'; then echo "pwmchip4:pwm0 exported" else echo "pwmchip4:pwm0 export failed" fi if sudo sh -c 'echo "1" > /sys/class/pwm/pwmchip4/export'; then echo "pwmchip4:pwm1 exported" else echo "pwmchip4:pwm1 export failed" fi if sudo sh -c 'echo "0" > /sys/class/pwm/pwmchip6/export'; then echo "pwmchip6:pwm0 exported" else echo "pwmchip6:pwm0 export failed" fi if sudo sh -c 'echo "1" > /sys/class/pwm/pwmchip6/export'; then echo "pwmchip6:pwm1 exported" else echo "pwmchip6:pwm1 export failed" fi I was happily drinking my 10th coffee when i noticed the following: First boot: debian@arm:~$ cd /sys/class/pwm/ debian@arm:/sys/class/pwm$ ls pwmchip0 pwmchip2 pwmchip4 pwmchip5 pwmchip6 Second boot: debian@arm:~$ cd /sys/class/pwm/ debian@arm:/sys/class/pwm$ ls pwmchip0 pwmchip1 pwmchip2 pwmchip4 pwmchip6 Firstly the result of my little script gives me a total of 7 successfully exported pwms. Shouldn't there be 8 ??? Secondly the numbering of the pwmchips is not consistent, and it is going to cause some issues when I develop the following C++ part. Any idea ? Thanks in advance. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
