I've got a couple of ARM SBCs without proper RTC but with USB GPS receivers
that set the clock without network. After a small amount of fussing, it
seems I can get gpsd and chrony to steer the clock to within a few
milliseconds of NTP time. Plus or minus 10ms is good enough for my
application.

The first few pages of google didn't turn up the pinout for the GPS module;
perhaps you could get out an oscilloscope and see if the PPS line is
connected? I did find one document (
https://www.farnell.com/datasheets/28007.pdf) suggesting that the TIMEMARK
signal is optional, so they may not have even connected it.

https://chrony-project.org/faq.html#_how_should_chronyd_be_configured_with_gpsd
https://austinsnerdythings.com/2021/09/29/millisecond-accurate-chrony-ntp-with-a-usb-gps-for-12-usd/

On Fri, Oct 31, 2025 at 4:37 PM Stuart Blake Tener <[email protected]>
wrote:

> GPSD users, developers, et alia:
>
> I have a General Dynamics GD8200 laptop that is inclusive of an internal
> GPS receiver. I was able to get GPSD running and cgps does show the
> satellites it sees, etc... However, I am a bit lost as to how to ascertain
> if I have pps capability and how to configure the software such that I can
> access it for setting the time on my laptop.
>
> However, if indeed the GPS internal to my laptop does not have PPS
> capability, I am wondering if and how I can use the time within the GPS
> strings to set the clock in the laptop as well. I realize it is less
> accurate, but I am not doing anything transactional with the laptop so if
> it is 10 to 20 seconds behind every day I really not that concerned about
> it.
>
> I am not sure if I am still a member of the list (I do not get daily or
> weekly emails) but I may have just disabled receiving them in the past.
>
> Thanks in advance to everyone on the list for any guidance that may help
> me.
>
>
> Very Respectfully,
>
> Stuart Blake Tener, BScCS, N3GWG (Extra), MROP
> Computer Scientist / FCC Licensed Radio Operator
>
> Las Vegas, NV / Philadelphia, PA
>
> +(1) 310.358.0202 Mobile Phone / WhatsApp
> +(1) 215.338.6005 Google Voice
>
> Amateur Radio IDs: DMR: 3132252[nn], 3132499 and NXDN ID: 6627
>


-- 
GDB has a 'break' feature; why doesn't it have 'fix' too?

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