[solved]: EnOcean Pi and Fhem, linux issues

Hello,

A lot of the competitors have already gotten their EnOcean Pi talking to their devices, but I'm still having trouble.

I've been following Todd Cowley's post http://www.element14.com/community/roadTestReviews/1795.

I'm still having issues with "Can't open /dev/ttyAMA0: Permission denied" error in the Fhem log file. I disabled the serial port using the script, and I've verified that AMA0 does not appear in inittab or cmdline.txt. Todd suggested that you add users "pi" and "fhem" to the tty group. I didn't have a user fhem, so I had to add that user. But even after that, I still get the permission denied message when accessing /dev/ttyAMA0.

Is there something different on B+ vs. the B that Todd was using?

Thanks for any advice.

Eric

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kipe over 10 years ago +1

Correct group to add the user to is "dialout". From the following you can see that the device owner is root and group is dialout, both have read (r) and write (w) permissions. pi@raspberrypi / $ ls -la…

michaelwylie over 10 years ago

Have you tried disabling the Pi Camera? A few bloggers have mentioned that they couldn't get it to work until they did that.
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electronichamsters over 10 years ago in reply to michaelwylie

I don't have a pi camera on my pi. It's just a stock Pi B+ from element14. But I ran raspi-config to confirm that it's disabled.
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kipe over 10 years ago

Correct group to add the user to is "dialout". From the following you can see that the device owner is root and group is dialout, both have read (r) and write (w) permissions.
pi@raspberrypi / $ ls -la /dev/ttyAMA0
crw-rw---T 1 root dialout 204, 64 Jan 1 1970 /dev/ttyAMA0

Of course you can try starting FHEM as root by running the start script with "sudo". Of course try not to do this constantly, as programs should only run with as low privileges as they can.

//E: Also remember to log out and log back in (or just reboot) once you've added the user to the group, so permissions update.
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electronichamsters over 10 years ago in reply to kipe

Kimmo,
Yes, that's it, I had the wrong group.

usermod -a -G dialout pi

That added it to the right group. Thanks a lot for the help!
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michaelwylie over 10 years ago in reply to electronichamsters

Good to hear!
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