I think there is nothing more pleasing than having extremely precise measurements at your fingertips. Like time. While in the past it was quite problematic to measure time accurately (not talking about sundials, but... why not? ;)) - mankind has created one precise time source as the byproduct (read: "waste") for usage in accurate navigation: GNSS and their different kinds like GPS, Glonass, Galileo, BaiDou and others.
Taping into this time source and providing it to your local computer network via NTP has been done by countless people and is an extreme rewarding task. Is it necessary? Maybe not. Is it really cool? Yes. And now it is even easier as you don't need to configure it yourself, but can use the balenaHub and the preconfigured gpsTime project.
Basically you just need an RPi B+ (2/3/4), Micro SD Card, Powersupply and 3v3 TTL Level GPS Module with PPS Output. The rest is just done by going on the balenaHub entry shown above, creating a free account and flashing balenaOS onto your SD card, booting the RPi on the internet for the first time and let it get the needed containers. Afterwards you can use the RPi offline and still enjoy your precise time source.
More details can be found in the Github Repo and you can work and improve that project to your hearts content. I am probably going to do an PiAndMore talk about it - and use the project myself as a block for precise timing in some support equipment.
hi,
is your GPS module powered directly from the 3.3V of the RPi?
is the RPi's 3.3V rail of the header strong enough to power that module?
how is the performance of that GPS module - do you get good GPS signal?
Hey there and thanks for the comment (and I assume original repo :)?).
Yes I do power the CAM-M8Q directly from the GPIOs. It does have a maximum draw of 71 mA ( https://learn.watterott.com/sensors/cam-m8q/cam-m8.pdf ) - however, mostly does pull a lot less (~30mA). The old RPi (non plus generation) had only about 50 mA current "headroom", but the + models seem to have more than 800 mA ( https://raspberrypi.stackexchange.com/questions/51615/raspberry-pi-power-limitations ).
The module does work great, I had once or twice a day a short disruption when Chronyc decided that it lost its timesource, but it came back later on. In the end the breadboard seemed to be the reason for that problems and a bad connection. However, I must admit that I have the module installed on the highest floor, so it is just shielded by the roof. But this can also be dealt with, as this breakout by watterott also has some GPS antenna connectors, so even if one has "no location benefit" and the antenna should be not sensitive enough, this should be a possible solution. I am really happy with the size/performance/price ratio of the modul :).
thank you for the information
and yes, your assumption i right...
i always spy the others repository, when i get a star...
thank you 😉
You're most welcome, I got to thank you - I tried a lot of different configurations and tutorials, yours was the first one to really reliable work :)!