Hello all. I have been trying to connect an external GPS over USB as described in the docs.
I put line /home/pi/APMrover2.elf -A udp:191.168.1.182:14550 -C /dev/ttyAMA0 -E /dev/ttyUSB0 & in my /etc/rc.local file and APM starts up on boot. I get telemetry to GCS over uart radio. I get wifi connection for SSH. I get GPS1 (built-in) but I get no GPS2 data in the GCS. Both GPS are set to auto. I can confirm that data is coming in because if I type
screen /dev/ttyUSB0 I see line of garbage characters. So the GPS is sending something. I have no idea how to make the garbage chars readable. Inverted mode ?
I am assuming the the USB0 comes in over serial 3. Is this correct ?
I kind of did a work around here. I put the telemetry radio on USB -C /dev/ttyUSB0 and put the external GPS on the uart with -E/dev/ttyAMA0. The uart brings the data over serial 3 and voila! it shows up on MP as the second GPS. BTW in the developer examples GPS.py does not work but gps.cpp works fine.