Hi JeanSeb,
Are you using rpi2 or odroid-c1?
It took me ~5 minutes from open box to running the navio sensor test to validate communication between navio+ and rpi2. And that was just by following the steps on the online doc.
I would say good starting point is to run some example app.
The online doc is pretty good.
The online doc also explains how to download the APM image and run it.
Once running you can communicate with the board using one of the dronecode GCS running on your PC to do the setup for your copter.
The APM binary does not come installed with the Linux emlid image so you do need to install it manually.
Maybe this is the step that you are missing?
You need to clarify with us what step you are in. Did you load the RTOS on the Pi? Did you install the APM? http://docs.emlid.com/ goes through the steps very clearly. Did you follow these?
Hi Jeanseb,
Have you tried the following 3 tests, which one is failing?
Test #1: plug the RFD900 to a PC and see what shows on a console screen. This will confirm the uart connection is working at expected speed.
Test #2: use udp to send telemetry to a PC (cable or wifi). This will confirm the navio+ is working properly.
test #3: use uart with APM again but connect to a PC instead of RFD900.
Please report the results. Those tests won’t fix anything but will help narrow down the problem.
Also I believe the RPI is 3.3v level, 8bit, no parity, 1 bit stop and no Hw flow control.
You might need a ttl to rs232 level converter to your PC.
You also can use Serial over USB with a proper USB to serial converter.
Is the RFD900 use ttl level with same uart setup as RPI (indicated above)?