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Looking at this posts as a discussion on general SDI-12, I have the Mayfly interface working for a Insitu LT500 Water Level monitor in a prototype capacity.
The LT500 requires an 8-36V Excitation, so I put in a series booster, +12V https://www.pololu.com/product/2117, and connected the other end to Grove 4pin JST-PH cable (std one cut in half)
I did use the standard SDI12 lib, and just created a header file for the InsituTrollSdi12.h for the interface. So very easy.
Thanks for everyone contributing to SDI-12 to make it so easy.
I’d be happy to post back the InsituTrollSdi12.h if anybody wants.
It does take a little setup on the LT500 mapping the sensor value on polling to where the SDI12Sensors.cpp expects it – though my notes are a bit hazy on what I did.
Since the SDI-12 spec defines clamping excess voltages to ground (lightening/ESD), today I’m in the process of creating a true SDI-12 physical interface with the level shifter BSS138 ~ one side pluggable into a Grove 4pin/5V, and the other side taking the SDI-12 3wires.
Be happy to share the PCB/cct/BOM with anybody interested.
The target is to deliver the results over a Verizon signal ~ thanks to @mbarney for suggesting the Digkey SIM and data plan https://dataplans.digikey.com . It does require setting the apn to VZWINTERNET. Its not as easy as hologram to setup.
