Comments on: Raspberry Pi Buster – GPS Dongle as a time source with Chrony & Timedatectl

By: Roger

Roger — Sun, 26 Jun 2022 16:57:17 +0000

Hi Mike

Installed GPS as per your instructions and seems to work fine. However, a direct side-effect of installing the GPS software is that Flrig is now unable to communicate with my IC7100.
This appears to be caused by a USB conflict, but not sure how to resolve it. Have you encountered this issue and can you suggest a resolution?

73 de Roger.

By: Didier B

Didier B — Wed, 16 Mar 2022 14:15:49 +0000

Used this with Raspi OS 64. Everything is going fine, python-gi-cairo can no longer be found, but doesn’t prevent xgps to work. Probably integrated in Debian 64 at last …
The only little issue I met, is that after a reboot, I will first get in answer to the ‘chronyc sources -v’ command the following : ‘#? NMEA …’ repeatedly until I use a gpsd client, e.G. cgps, then I will find the so awaited for ‘#* NMEA …’
Even interrogating ‘sudo systemctl is-active gpsd’ is enough to make everything all right.
Most probably the source of the issue is in gpsd itself, as I had allready seen the same phenomena in OpenCPN (need to launch a gpsd client before getting any NMEA data in OpenCPN

By: JohnM

JohnM — Tue, 08 Mar 2022 16:03:32 +0000

In reply to JohnM. reflock, oh, should be refclock!!

By: JohnM

JohnM — Tue, 08 Mar 2022 16:00:17 +0000

Hi Mike, thanks for the tutorial! I have cgps working, chronyd and gspd active, but only as long as I don’t have the reflock line in chrony.conf. I am having an issue when I add the reflock line to the /etc/chrony/chrony.conf file. It tags the reflock line as “invalid directive”, whatever that means.
My /run/gspd.sock file is empty, always. What is the purpose of this file? What should it contain?
My device is a USB dongle by TSI (GM-3N) based upon the MTK MT3333 chip. It does not support PPS outputs via NMEA (firmware is too old).

By: David

David — Sun, 13 Feb 2022 09:53:18 +0000

This helped a lot! Especially the part about commenting out “START_DAEMON” and simply adding “refclock SHM 0 offset 0.5 delay 0.2 refid NMEA” to chrony’s config did the trick!

By: Sean Mac Suibhne

Sean Mac Suibhne — Fri, 17 Dec 2021 16:33:02 +0000

Sorry I see I introduced a typo there at the end of the third line.
Replace the ? with a ”
# START_DAEMON=”true” ( Comment this line out )
USBAUTO=”true”
DEVICES=”/dev/ttyACM0″
GPSD_OPTIONS=”-n”

By: Mike Richards

Mike Richards — Fri, 17 Dec 2021 15:45:43 +0000

In reply to Sean Mac Suibhne.

Hi Sean,

Glad to hear you find the post useful. I’ll add a comment about your findings.

Thanks,

Mike G4WNC

By: Sean Mac Suibhne

Sean Mac Suibhne — Fri, 17 Dec 2021 15:19:05 +0000

Hi,
I love this blog item because I wouldnt know hot to set up gpsd or chrony with out it. I have used your settings to set up al my Rpis and my linux computers.

However recently something has changed on my Linux and Rpis so that gpsd and chrony no longer work.

The problem is cured by editing /etc/default/gpsd

# START_DAEMON=”true” ( Comment this line out )
USBAUTO=”true”
DEVICES=”/dev/ttyACM0?
GPSD_OPTIONS=”-n”

This works on all my RPis and Linux .

Please keep up the great work!

Seán Mac Suibhne

By: Mike Richards

Mike Richards — Wed, 13 Oct 2021 18:12:32 +0000

In reply to Sanjith. Glad to be of help. Mike - G4WNC

By: Sanjith

Sanjith — Wed, 13 Oct 2021 17:38:50 +0000

Excellent thank you