I have two Facet units with Holybro radios. One is set as a base and the other as rover. The base has come up and is transmitting RTCM corrections over the radio (at least according to the LEDs - solid green, blinking red). The rover’s radio also appears to be receiving the corrections (at least according to the LEDs, solid green, blinking red), but the rover isn’t moving from DGPS to RTK Float or RTK Fix. In U-Center, it appears RTCM messages are not being received. UART2 is setup to RTCM3 with baud rate of 57600, which I assume is the default settings for this unit.
Anyone have any thoughts on what might be going on? These are two new units (and radios) that I just received and I thought this might work out of the box without any configuration changes.
l_boltzmannEMB:
Is there a configuration manual or setup tool for the radios? I’ve only found some mention of using Mission Planner to do so. Seems overkill.
I used Mission Planner to confirm baud rate so you can ignore this question.
Okay, user error big time… went through changing everything around, testing cables, checking everything in U-center and then noticed I had the radios plugged into the Data port not the Radio port. Ugh.
Now I can see RTCM corrections on my radio attached via USB to my PC via U-center. Unfortunately, I’m still not getting an RTK Fix on the rover station. It’s sitting at about .258 m position error with the Fix type being 3D after 30 minutes. I’ve switched out these two radios and same behavior. Never get a RTK float or RTK Fix reading.
I’ve tested out the cable between the radio and the Rover for continuity and proper pin selection. Looks good. I’ve switched them between the base and rover as well. I also switched base and rover.
Any other settings I should check in u-center on the Rover? Any other thoughts?
Yes, Mission Planner is overkill. The radios can be configured using Hayes modem style AT commands and a serial terminal on your PC. If you’re of a certain age this will bring back memories. The Holybro manual I have does not describe how to do this.
But the Holybros use a common SiK firmware, you can search for “sik firmware at commands” for info.
Unless you are very fortunate, you need to do this outside to get an RTK Fix. And you need a clear view of the sky. I can’t get this to work on my kitchen table, my desk, or in my back yard under the trees.
Though if you aren’t even getting RTK Float, I’d suspect a comm issue.
I’d pull u-center out of the mix to simplify things. The Facet firmware will configure the F9Ps properly. Then try the following:
Reset both Facets to factory defaults; something might have gotten changed.
Momentarily put both Facets aside. I’d connect both radios to a PC with serial cables, open up two terminals, one to each port (or use two PCs, might be less confusing). You should be able to type in one terminal and have the data be displayed on the other. And visa-versa. You’ll check the radio-radio connection and the baud rate in the process of doing this, as you’ll need to set the terminal software to the right baud to talk to the radios.
I’ve had problems with individual pins in those tiny JST connectors on the Facet-Radio cables coming loose and making contact intermittent contact. Look closely where the wires come out of the backs of the connectors. For me, sometimes one pin is sometimes sticking out a tiny bit and doesn’t make contact with the radio connector on the Facet, or to the radio. I carry a very small screwdriver to push loose pins back in. If one of the radio cable data pins on the rover is loose, the green LEDs on the radios will be solid (good radio-radio connection) and the red LEDs will blink in concert (data flowing from base to radio to radio), but the data doesn’t get to the Rover.