[Xastir] Xastir and Mobilinkd Tnc 1 Bluetooth tnc

[Kevin Ratcliff]

On Thu, Nov 6, 2014 at 9:14 PM, Bryan Irwin <kf5tot at outlook.com> wrote:
> I'm looking for a little help here.  I'm running Xastir 2.07 on Ubuntu 14.04 on a Lenovo ideapad s10-3 and I want to use my Mobilinkd tnc with it and I'm at a dead end.

I don't know how much help I'll be as I don't currently use bluetooth
with my Debian box, but I have used a bluetooth adapter with Ubuntu
and xastir to connect to the TNC on my D700 a long time ago. I found
it to be unreliable and I opted to hard-wire it with a serial cable
instead.

In 2009 I wrote a wiki article for bluetooth and Ubuntu 9.10:
http://xastir.org/index.php/HowTo:BluetoothTNC. Some of it probably
still applies?

> I can connect to the tnc in terminal using sudo rfcomm connect 0 just fine but when I try to add it in the interface control in xastir and start it I get an EACCESS ERROR  Interface Error! Error opening interface 0 Hard Fail.  I've tried the chmod command  and am still in the same place.

You may have run into one of these longstanding bugs:

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/570692
https://bugs.launchpad.net/ubuntu/+source/bluez/+bug/1014992

First I would make sure your user account is in the 'dialout' group on
your box. My understanding is that this is used to control access to
serial devices in linux, not just modems. So I think you need to be in
this group to access /dev/rfcomm0 (which is a bluetooth serial port,
thus considered a 'modem').

Exit xastir (or maybe just disable/stop the rfcomm0 interface on the
xastir Interfaces menu if you don't want to shut down xastir
completely for some reason).

Then run your 'sudo rfcomm connect 0' command again if the bluetooth
link isn't still connected. I think that in theory you wouldn't need
to run this with sudo but maybe that's what the Ubuntu bugs are about?
I didn't read the bug reports very carefully.

Next I'd try opening /dev/rfcomm0 in a serial terminal program like
gtkterm or minicom (but don't use sudo for these) to see if you still
get a permissions error. If you can open the device that way, you
should be able to open it in xastir.

If the serial terminal programs still won't open the rfcomm0 device
after your account is a member of dialout I'm afraid I'm out of ideas
right now, and I don't have an Ubuntu box to experiment with in front
of me. I don't think it's an issue with xastir, but rather some sort
of issue with system permissions.

> Any help would be greatly appreciated.

Hopefully that gives you some things to try. Maybe someone else more
knowledgeable will chime in.

When you figure it out, perhaps you could update the wiki article.

Kevin
KB9MQU