I have ESP node running since yesterday based on Wemos D1-mini board and RFM95 (and the LoRa shield of Ideetron). It is based on a port of the LMIC-v1.5 source base with changes to hal.cpp and others for this architecture.
git: https://github.com/things4u/LoRa-Thing
The code is a copy of my sourcetree so do not forget to include the LMIC-v1.5 library from the libraries directory.
And please remember this is work in progress. So although the sensor transmits its hello world message, the ESP is known to be difficult so use at your own risk.
Mine will stay on the bench/breadboard for a few days until it has proven to be stable. Will than probably work on energy efficiency (like to run it on a battery).
Cost for this one:
- Wemos D1-mini $ 4.00 Aliexpress
- RFM95 $8.00
- Shield Euro 7.45 (ex VAT0
- Antenna Euro 5.39 (ex VAT)
But when shield and antenna are not used (make your own) it is possible to make a really cheap powerful node so it seems.
Maarten