What is the GPS sentence format for PX4

#1

I am working on an artificial positioning interface and want to replace the regular GPS module with another device. What is the sentence format required for input on the GPS port on the Pixhawk so I can duplicate it?

Thanks,
Joe

#2

First of all I would think that just supplying information over MAVLink either using the GPS messages or external vision messages would be easier. If that’s not an option, you could fake UBX by looking at the ubx driver and/or the specs, or you could try to fake NMEA which is somewhat understood by the ashtech driver.