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I've been stuck on this for a while my problem is I cant access GPS data for a ublox node. I am connecting to a Raspberry pi 3 that is running a RPI 2 Snappy Image. I am connecting to the PI through a SSH on a ubuntu 14.04 laptop.

I am running the following command and getting this error: (updated output with correct port spelling)

    ubuntu@ubuntu:~$ roslaunch ublox_gps ublox_device.launch 
... logging to /home/ubuntu/.ros/log/cefae814-d237-11e7-8ade-b827ebffc577/roslaunch-ubuntu-1799.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server


 * /rosdistro: kinetic
 * /rosversion: 1.12.7
 * /ublox_gps/debug: 1
 * /ublox_gps/device: /dev/ttyAMC0
 * /ublox_gps/dgnss_mode: 3
 * /ublox_gps/dr_limit: 0
 * /ublox_gps/dynamic_model: portable
 * /ublox_gps/enable_ppp: False
 * /ublox_gps/fix_mode: auto
 * /ublox_gps/frame_id: gps
 * /ublox_gps/gnss/beidou: False
 * /ublox_gps/gnss/glonass: True
 * /ublox_gps/gnss/qzss: False
 * /ublox_gps/inf/all: True
 * /ublox_gps/nav_rate: 4
 * /ublox_gps/publish/aid/hui: False
 * /ublox_gps/publish/all: True
 * /ublox_gps/publish/nav/posecef: False
 * /ublox_gps/rate: 4
 * /ublox_gps/save/device: 4
 * /ublox_gps/save/mask: 3103
 * /ublox_gps/uart1/baudrate: 19200
 * /ublox_gps/uart1/in: 32
 * /ublox_gps/uart1/out: 0

    ublox_gps (ublox_gps/ublox_gps)

auto-starting new master
process[master]: started with pid [1813]

setting /run_id to cefae814-d237-11e7-8ade-b827ebffc577
process[rosout-1]: started with pid [1826]
started core service [/rosout]
process[ublox_gps-2]: started with pid [1829]
terminate called after throwing an instance of 'std::runtime_error'
  what():  U-Blox: Could not open serial port :/dev/ttyAMC0 open: No such file or directory
[ublox_gps-2] process has died [pid 1829, exit code -6, cmd /home/ubuntu/catkin_ws/devel/lib/ublox_gps/ublox_gps __name:=ublox_gps __log:=/home/ubuntu/.ros/log/cefae814-d237-11e7-8ade-b827ebffc577/ublox_gps-2.log].
log file: /home/ubuntu/.ros/log/cefae814-d237-11e7-8ade-b827ebffc577/ublox_gps-2*.log
^C[rosout-1] killing on exit
[master] killing on exit
shutting down processing monitor...
... shutting down processing monitor complete

I checked that the port was correct by using

cat /dev/ttyACM0 

it outputted my GPS Data that I was looking for, I assumed that I was permission were off so I did the command


this is the output

ubuntu adm dialout cdrom floppy sudo audio dip video plugdev netdev lxd

it says I'm in the dialout group, so i assumed my permissions were fine. when I do

ls -la /dev/ttyACM0
crw-rw-rw- 1 root dialout 166, 0 Feb 11  2016 /dev/ttyACM0

So there is a problem with my # after dialout its should be 666 right? I tried using

sudo chmod 666 /dev/ttyAMC0 

No change to the permissions.

Does anyone know how to change the dialout 166 problem? thanks - or any other solutions that would allow me to open the port or read the GPS Data.

Originally posted by pacifickid9 on ROS Answers with karma: 1 on 2017-11-24

Post score: 0

Original comments

Comment by billy on 2017-11-24:
The error message said there was no file /dev/ACM0, and then you start to explain the effort put into /dev/ttyAMC0. They're not the same thing.

Comment by pacifickid9 on 2017-11-24:
Sorry I miss typed into the launch file parameters, but i retested it with /dev/ttyACM0 and got the same result.

Comment by pacifickid9 on 2017-11-25:
I think i spelled it wrong I got another error so this one must have been solved thanks guys ill be more careful next time!


1 Answer 1


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but i retested it with /dev/ttyACM0

can you please check again? It's ttyAMC0, not ttyACM0.

After you've changed the launch file / parameters, update your original post to show us the output.

Originally posted by gvdhoorn with karma: 86574 on 2017-11-25

This answer was ACCEPTED on the original site

Post score: 0


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