Writing to the serial port (GPIO TX/RX)

[gundark]

I am trying to use openhab to control arduinos. This requires my user to be able to write to the serial port, there is allot of documentation on how to do this on other distros but I can’t seem to find info on it for Mate.

I have added the user to the dialout group.

$ groups openhab
openhab : openhab dialout

However I cant write to the port still, other distros say to do things like edit /boot/cmdline.txt which appears to already have been done, maybe by apt-get?

dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait quiet splash

Those same posts say the /etc/inittab needs to be edited, however it doesn’t exist,
Can someone point me in the right direction?

[richard_mark]

Got the same problem, anybody?

[wolfman]

Hi people,

it may be a users and groups issue, see the following thread:

Users & Groups setup

I was looking at users & Groups and added a user. This user came up as custom so I changed to desktop user. Then I noticed the first login ID was also set as custom and not as administrator and then wondered if I should have left the added ID as custom? What is the difference between custom and others?

[richard_mark]

Problem solved.

I did three things:

1. modified the edit /boot/cmdline.txt file to this
   dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait quiet splash
2. ran raspi-config
   sudo apt-get install raspi-config
   sudo raspi-config
   select 9 Advanced options -> A8 Serial Port -> Would you like shell to access serial port -> Select No
3. Add your use to the group
   sudo gpasswd --add ${USER} dialout
   reboot

Should work now.