Reading raw serial data

PX4 Autopilot
1

I’m assuming there is a way to see raw serial data being fed into the autopilot via Telem_2 port but I haven’t found it in the forums.

We are working to integrate a GPS receiver using NMEA 0183 on Telem_2 but having issues and would like to view the raw data the autopilot is seeing in order to debug. Have tried uOrb listener, MAVlink inspector, accessing through /nsh, and printing to log files. No luck. What am I missing?

2

You could just use the GPS driver and then set the protocol to NMEA:
GPS_2_PROTOCOL.

Otherwise, you need to write your own driver that reads from serial.

3

Hye Julian,

This is exactly what we intend to do. The autopilot has been setup to configure a secondary GPS on the Telem_2 port per the Configuring a Secondary GPS (Dual GPS System) instructions.

I want to read the raw serial data so we can confirm our hardware is delivering the data stream correctly.

4

Ive found the serial_test and serial_passthru system cmds. Seems like this is what I need. I can run serial_test but not serial_passthru. Will serial_test print out raw serial data?

5

For anyone who finds this in the future, use serial_test in nsh to read raw serial

6

Hi Justin, I was wondering if you are able to use dual GPS ? Similar to your configuration I am trying to use Telem3 and GPS port and configure according to Global Navigation Satellite Systems (GNSS) | PX4 Guide (main).
When I disconnect the primary one, secondary is not stepping up and vehicle is not accepting GPS2 even if its reading the raw mavlink inspector.

I appreciate if anyone can provide some insights.

Thanks.