I am looking into code of ubxtool to look for a way to ask the gps to tell me about the RTCM data it has received. gpsd log tells me that it relays rtcm data at regular intervals to the gps, but the RTK led does not go off, so I am trying to follow the data stream of the RTCM from the ntrip url down into the gps. I guess this particular easy-access poll function has not been implemented yet.
u-center ntrip client is able to read the same RTCM data, feed it to the gps and make the LED go off (RTK float at least)
What I am chasing here is using two F9P modules one for rover and one for base. The base will use survey-in to find its coordinate, and then start outputing RTCM correction data to the rover. The F9Ps are connected to raspberry pi through usb. radio communication is done through 868 long range radio also connected to raspberry pi on usb.
For a start, I am using a nearby RTCM source transported by euref-ip.net
which is the one I fed to u-center.
Of course, u-center may have done some configuration behind the scene which I am not aware of. u-center tends to do that.