Got Ublox F9P working with FJ Dynamics and Trimble

MSM7 definitely works with the 372. That’s what I use. What do you mean it says “no signal detected?” Where does it say this? When you go to the RDI interface (on a Pro 700 that’s Diagnostics->RDI) what does it say? Usually it will say CMR A something, which indicates the age of the RTCM messages it is getting from your base station. If the age is between 1 and 2 you know it’s seeing the base station messages at least. And of course is your Port C baud rate set to the same thing as your ESP32?

I’m not real familiar with the 372s but do recall a 252 I had years ago would only allow input of correction data on certain ports. Do you use AgRemote to change the port settings? If so, make sure when you change the input to RTCM it remains unchanged after you power cycle your 372 or disconnect AgRemote and re-connect. Not to state the obvious but also make sure your baud rates align.

You can make sure you are getting clean RTCM data through your device that is inputting the 1008 message by utilizing a program called SNIP. It’s free to download and you can use a USB to serial adapter to your computer to read a serial stream and view the RTCM data in their RTCM viewer. I initially had some issues with mine and this helped me see exactly what was coming through my arduino where I was injecting the 1008 message.

Last thought…do you have an NTRIP client stream where you could input CMR data to ensure the 372 is actually receiving the data? I think through SNIP you can connect to available streams all over the world. You could potentially use any of them that have CMR data and push it to your 372. You obviously wouldn’t want to use it for steering but it would be a way to check that your 372 is receiving data.

Where are you located?


Ok I’ve downloaded SNIP connected it to my ESP32 usb port and if I look at Raw HEX data then yes it’s streaming but when I go to “show in RTCM3 viewer” there’s nothing, I’m somewhat confused the arduino sketch on my ESP32 I copied from

and then modified that a little for example serial communications

If the 372 is unlocked for RTK? I’m assuming yes because I have 5 of these receivers and this is the only one that has “RTK” option in “correction type” under settings. I asked the case ih tech guy and he couldn’t give me a quick answer

Under RDI-CMR it stays at 0% which makes sense if the data is seemingly not clean data

My Receiver settings are same as this guy is showing it in this video

Yep my baudrate is 38400 on ESP32 same as on the receiver

I’m from San Pedro, Paraguay

My whole idea is based on Michael torries project

At this point I’m not sure what’s wrong because I stack the xbee module on a ardusimple rover, I get a fix quickly, put it back on ESP32 and the messages seem to be incomplete


Is the Trimble configured for CMR? That is Trimble default language, your F9P must be giving RTCM 3.x.

Quick thought….are you going straight from the esp32 to your computer or 372 or are you running it through a logic converter? I’m willing to bet you have 3.2TTL logic from your esp32 that needs converted to regular serial that your 372 or computer can read.

I use these. Let me know if the link doesn’t work.

HiLetgo 5pcs RS232 to TTL Converter Module COM Serial Port Board MAX3232 MAX232CSE



It’s a bit odd that SNIP isn’t decoding anything coming from your ESP32. Not sure what to say there. You should see valid RTCMv3 packets. Which serial is your input and which is your output on the ESP32?

As for the ESP32 stack are you converting the serial output to RS232 with a converter? The ESP32 speaks TTL serial only, which is 3.3v as @EricLit says. The 372 requires actual RS232 signals. I use a TTL to RS232 converter for mine. Any that can handle 3.3v will do. Doesn’t matter if you use DTE or DCE adapters, although the pinout for TX/RX is reversed on the one vs the other. DTE (male pins) RX is pin 2 and TX is ping 3 on the DB9, but on the DCE (female pins) it’s opposite.

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Ok I found the problem, it’s getting corrupted over the radio link, I ended up connecting the ESP32 directly to the ardusimple base on UART2 and then I saw the messages, 1 thing I learned if SNIP can’t decode something on the first run then I had to kill and restart SNIP because if I just disconnect and reconnect it’s not even trying, so that toke me a long time to realize

If I know about the serial conversion? yes I have the same MAX3232 chip

One thing I can’t figure out why these Xbee SX radios can’t do a better job, has anyone dealt with this problem already?

I connected everything directly to the 372 and immediately got a fix, it works very nicely except it’s only getting 9 or 10 satellites, with RTX I get 14-16, I’m wondering if I can add a message to get more sats?
Currently I’m sending 1005 1008 1077 1087 every 2 seconds and 1230 every 5 seconds

Thanks Eric for telling me about SNIP it’s been very helpful to identify the problem with it, it took me a while to learn how it works but now it’s a game changer
But really thanks to everyone I would’ve giving up probably if you guy’s didn’t step in to share some experience

I need corrections over 15 km radius with hills and unstable Internet, what would you guys recommend? Setting up a couple bases or is there a radio solution for this? Maybe a 20m pole? So far I’m not overly impressed with these Xbees, they’re advertised to cover 18 km but they hardly do 1 km…
I’m willing to spend a couple grand as long as it works

Is this the 1 watt SX pro? I had mine up about 25 feet and could reach about 5 miles pretty well, but terrain got in the way quite a bit. If you’ve got hills you need to have height. The higher the better. 20m would be more than enough for my terrain, but I don’t know what your hills and trees are like.

I have my antenna up at about 30 feet, enough to get line of sight to my whole farm, but the coax cable I made up for it seems to have problems as I cannot get signal more than half a mile. So either my old 9Xtend transmitter module has issues (very possible as it’s quite old and I do have a newer SX Pro to try), or the cable is not good. I used to get good range with it.

The 372 lets you set up RTX as a backup. If you get an RTK fix, it will let you fall back to RTX for 15 minutes at a time if the RTCM signal is blocked or taken away for short periods of time. It works transparently.

Hello everyone,

I’m located in Slovenia. After Septembre 2022 I’m having problems connecting my ag372 to my RTKBASE mount name PRIME.
I didn’t change anything. After talking to the creators of RTKBase someone mentioned that I should check the Firmware and update it to the latest one. Has anyone expirience similar problems?



You need email.

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Thank you for the reply. I’m using the centipede caster.

Looking a little light on messages? What’s rtkbase set to export?


It only receives GPS and Glonass so surely that list is complete?

I’m guessing 1006(30),1008(10),1077,1087,1230(30)


Those are the messages I’m using with my 372.

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Like torriem said. This messages are perfect for the RTKBase and Trimble 372/382. I need to look at the count, something seems odd.
It should be:
Seems like the messages aren’t coming to the Tractor. Any ideas what could be causing this?

Not sure, but if you can, temporarily open up port 2101 at home in your firewall and go direct to your home from machine. You’ll need your home machine’s external IP address. Using putty, then do:

netstat -ano | grep 2101

Hopefully you’ll see the incoming connection.

Hi, can you please check one more time. With ucenter and report back?
Mt point: PRIME

Hello friends! Discovered this useful forum! Now I’m just trying to set up the base on the ZED-F9P module to transmit corrections to the FJD autopilot.
This topic says that FJD works with MSM5 messages 1075, 1085 etc. However, the instructions for ZED-F9P do not indicate that this module supports MSM5 messaging, there is MSM4. Please tell me, does this mean that FJD will not be able to receive corrections from the ZED-F9P module?

FJ works with MSM7 messages just fine. I have an FJ system running off my F9P base.

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Currently running a F9P with wifi ntrip master over Centipede as a base for AOG.
What is the best option for making the base suitable for a Trimble rover? Would i need to run a Pi with my F9P to output the 1008 message?