[SOLVED] No switch button in BasicUI

Trainer · January 26, 2018, 5:20pm

Josar:

@Trainer so you miss the gpio group and all files which should have permission set for gpio are not set correctly.

Maybe a
sudo apt-get update
sudo apt-get dist-upgrade
would be the best choice. And then reinstall wiringPI

But here is what i found on how to set gpio and the file permission. I did not set it up myself.

Create a gpio group first:
groupadd gpio
add your users to that group:
usermod -a -G gpio pi
usermod -a -G gpio openhab
Test if it went right.
pi@raspberrypi:~ $ grep gpio /etc/group
gpio:x:997:pi,openhab
Reboot

Fix permissions of the sysfs GPIO file system.
sudo nano /etc/rc.local
add following to the bottom
chown -R root:gpio /sys/class/gpio
chmod -R ug+rw /sys/class/gpio
Next set up an udev rule to enable non root and gpio group user to acces GPIO files.
sudo nano /etc/udev/rules.d/80-gpio-noroot.rules
# /etc/udev/rules.d/80-gpio-noroot.rules
# Acces to GPIO without root
#
#  Change group
SUBSYSTEM=="gpio", PROGRAM="/bin/sh -c '/bin/chown -R root:gpio /sys/devices/platform/soc/*.gpio/gpio'"
# set acces permission
SUBSYSTEM=="gpio", PROGRAM="/bin/sh -c '/bin/chmod -R ug+rw /sys/devices/platform/soc/*.gpio/gpio'"
No reboot just trigger the rule.
sudo udevadm trigger --subsystem-match=gpio
But rebooting is always a good idea.

taken from here and here.

Thank you.
I do everything you explain me, but i got the same message, if i try to use codesend without sudo

wiringPiSetup: Unable to open /dev/mem or /dev/gpiomem: Permission denied.
Try running with sudo?

Josar · January 29, 2018, 7:08pm

Fresh installation of the latest Rasbpian is my last idea.

Trainer · February 1, 2018, 10:21pm

If someone has the same problem, after i follow this instruction, i can use it without sudo.

https://raspberrypi.stackexchange.com/questions/40105/access-gpio-pins-without-root-no-access-to-dev-mem-try-running-as-root

it should looks like this

$ ls -l /dev/gpiomem
crw-rw---- 1 root gpio 244, 0 Dec 28 22:51 /dev/gpiomem

if not, you can chance it with this commands

sudo chown root.gpio /dev/gpiomem
sudo chmod g+rw /dev/gpiomem