How can I set the system clock to GPS time?

Question

My computer is running Ubuntu 16.04 and has a GPS receiver connected to a USB port.

gpsmon shows that the GPS receiver is locked and running.

sudo gpsmon /dev/ttyUSB0 works great!

Why do I have to use sudo to run gpsmon every time?

Is there a way to set the system clock on Ubuntu 16.04 to the time being reported by the GPS receiver without using NTP?

Have you taken a look at pps-tools, or tutorials like gps on raspberry pi 3, or My ADSB Receiver Box – GPS Precision Time — J. Starnes, Dec 22 '17 at 05:43
To remove the requirement for sudo, add your username to the dialout group. sudo adduser username dialout — Jean-Marie, Dec 23 '17 at 16:20

score 1 · Answer 1 · answered Jan 03 '20 at 02:03

BTW, why do I have to use sudo to run gpsmon every time?

Most likely, your normal user account doesn't have privileges to /dev/ttyUSB0.

From the command line, type:

ls -l /dev/ttyUSB0

And it will return something like:

crw-rw---- 1 root dialout 188, 0 Jan  2 20:46 ttyUSB0

The "root" part is the user that owns the file, the "dialout" is a group associated with the device. You need to add your user account to the group "dialout" then you wont need to start gpsmon with sudo.

This should get you going:

usermod -a -G dialout yourusername

Hope this helps...

How can I set the system clock to GPS time?

1 Answers1