Hydrographic/ bathymetric survey: Lowrance LMS-525 C DF receiving NMEA 0183 problem (from Leica GPS 1200 RTK)
I want to connect Leica RTK GPS (Leica SmartAntenna + Leica RX1250 controller) to LOWRANCE LMS-525 C DF via NMEA 0183. The reason for that is I want to get precise (centimeter level) position of sonar readings. Unfortunately there is some problem and I cannot diagnose it. I sticked to the manual when connecting everything, but without success. In the opposite direction (transmitting position of sonar from standard Lowrance GPS) NMEA 0183 works fine and I can read GGA message on PC (via Parani bluetooth serial adapters and then in Python script).
This is the NMEA GGA message received from Leica GPS:
And this is the NMEA GGA message received from standard Lowrance GPS:
So they only differ in position decimal precision. I’ve also tried to transmit this Lowrance GPS NMEA GGA back to the sonar – without succes :/
I’ve tried to show everything on the video:
Here are also some useful pictures: https://drive.google.com/drive/folders/1SzBnptYiXg3HtKRgPSlmPxXXSCqDRiiO?usp=sharing
Link to Sonar manual found on the internet:
I will be very grateful for any suggestion and help!
We have a similar setup but the sounder (Lowrance HDS) sends Depth to the RTK data collector (DC) via Bluetooth.
Somewhere there needs to be a "null-modem", which can be achieved by changing the RX/TX pins on one side of the data link - you possibly don't have this on the DC-sonar setup.
On our Lowrance system, a yellow wire generally represents a "wake-up" wire, such that when connected, starting one instrument will trigger start up of another.
For the Privateer, these things are tricky but seeing as you have the data going to the PC, you must be very close - don't give up.
Also, check which sentence the sonar accepts for GPS position. I think there are at least a couple of different "versions" of position - just like for sonar depth, there are at least a couple of versions of depth.
Thank you for suggestion! 😀 I didn't try to send the depth to the controller. I'll try and let you know if anything came out of it.
Null modem is already connected to the serial cable going from DC.
What Data Collector do you have?
Ok, sending depth from sonar to the Leica Data Collector works! 😀 It's a pity, that it's sending it only in 1Hz rate :/
Thank you @Richard-Imrie so much for this suggestion! 😀
But if someone would guide me how to transmit Leica GPS data to sonar, I will be also very grateful. Leica can measure in 20Hz rate, so it would be huuuuge improvement 😉