[Bug]: GPS Time is *NOT* well synchronized to device clock 😕

[jstockdale]

Category

Hardware Compatibility

Hardware

Other

Firmware Version

2.5.19

Description

Hi folks,

I'm watching my GPS time on my SenseCap Indicator which is connected to an Air530 GPS from SeeedStudio. This is all supported hardware.

The GPS time does NOT regularly sync. Maybe once a day or something? It is constantly off and is almost never correct. Right now my device clock is off by over 40 seconds. Watching the serial output from the GPS unit, the time is very close to correct (well, maybe ~250ms off from the serial delay).

If GPS time is available and the device has a good fix. The device should prefer GPS time over mesh time. (Or maybe use NTP if NTP is set... unless there is a preference added for clock source.)

It seems to do none of these things. I'm guessing it's synchronizing like once every 24 hours. Either we should synchronize GPS time every time position is updated, or we should have a way to prefer NTP time.

Having the wrong time continually on a GPS connected device is suboptimal.

Thanks,
-@jstockdale

[fifieldt]

Thanks for sending in a report. I have that hardware and will try to reproduce.

[fifieldt]

Hi @jstockdale , I set up the Sensecap Indicator with an Air530 attached ... but the GPS was never actually detected.

It looks like the Grove connectors on the back connect to the RP2040, whereas the Meshtastic firmware runs on on the RP2040.

Further, I looked into the time code, and it looks like it does function as one would expect - applying GPS time in favour of time from mesh and time from NTP.

How have you got the GPS connected? Can you provide logs (https://flasher.meshtastic.org --> open serial monitor)

[mverch67]

To get the GPS working with indicator you'd need to flash this firmware to the rp2040 as documented in PR #5411:
https://github.com/Dylanliacc/Serial-Protocol-of-RP2040-on-Indiactor-for-meshtastic