Add GPS to RAK7258

I need time with my RAK7258 and tried to connect a GPS module to ttyS1, using UART1 of RAK634 computing module (pins B14/B15)and GPS PPS input (pin 19) of RAK2254 Lora module.

I had this up and running for a while, and saw UTC time in gateway’s metadata sent to the LoRa server, but it seems for some reason the configuration is not stable. Will retry with original U-Blox 7 module, since the semtech packet forwarder is using UBX protocol to get timestamps from GPS.

Can anyone here confirm, that UART1 of RAK634 is mapped to /dev/ttyS1 on the RAK7258 and the interface is usable (i.e. activated in kernel)?

Hi @cyberman54
I consult with team and yes, the /dev/ttyS1 is UART1 of RAK643. It is active in kernel.


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Thanks for this confirmation.
UART1 is on pins B14+B15 of RAK634, right?

Are these pins wired anywhere to on the pcb of RAK7258? Currently i soldered wires directly to the module.

I connected an (original, not counterfeit) ublox neo7 to UART1, and on digital oscilloscope i see that it is feeding data. But the gateway still shows no gps location and no time-of-day in metadata.

Any idea how i can debug this?