Home/Support/Support Forum/Xbee 3 wireless link between F9P GPS receivers
New and improved user forum site going live on 12/6 (All users will need to reset their password when the new forum is active)

Xbee 3 wireless link between F9P GPS receivers

0 votes
I want to send RTCM correction messages from the Sparkfun F9P base to F9P rover via Xbee. I have RTK fixed mode on my rover F9P using a wired connection, so I know the two F9P's are correctly configured per Ublox's Moving Base Application Note. I now want to replace the wired connection with a wireless connection between the bas and rover GPS's.

Following Sparkfun's advice, I configured my two Xbee 3 firmware to the legacy 802.15.4 protocol. My two Xbee 3 modules are talking to each other via Sparkfun Explorer adaptors when I type in XTCU console log. I set the Xbee 3 baud rate as the F9P's, namely 115200. Other than change the PAN ID, I made no other changes to the XBee 3 default settings.

My multimeter indicates about 3.3V at the F9P UART2 TX pin which outputs the RTCM messages. However when I connect this output to the Xbee 3 DIN pin, there is no data appearing on the XCTU console log. Could you please help me set up this wireless link between the pair of F9P receivers.
asked Apr 20, 2020 in RF Solutions and XBee by RicDG New to the Community (1 point)

Please log in or register to answer this question.

2 Answers

0 votes

Which port are you connecting to? From what I can find about this, the F9P main port is SPI and not serial.

Digi Support
answered Apr 20, 2020 by mvut Veteran of the Digi Community (15,515 points)
0 votes
I connected to the F9P port recommended by https://learn.sparkfun.com/tutorials/gps-rtk2-hookup-guide which states:"There is a second serial port (UART2) available on the ZED-F9P that is primarily used for RTCM3 correction data." I had also used this port for my successful wired connection between F9P's.
Page 17 of Ublox's F9P Moving Application Note says:"Set the base ZED-F9P UART2 to output the required RTCM messages"
answered Apr 21, 2020 by RicDG New to the Community (1 point)
The fact that you are not getting any data leads me to thinking that there is a wiring issue. If it was a baud rate issue, you would still get data. Just would be in a way that it was not readable. No data means that either the cables are backwards, voltage issue or something of that nature.