LMIC-node-ESP32 & RFM95-GPS Tracker

This repository is a fork of roelwolf/LMIC-node-gps-tracker and adds a gps functionality to the default LMIC-node

As per that repository:

• The code makes use of the library mikalhart/TinyGPSPlus
• The code was originally written for the TTGO T-Beam but I have adapted for any ESP32 & RFM95 Lora Module connected via SPI.
• I changed as less as posible to the original code in LMIC-node.h and LMIC-node.cpp. The additions are mainly between the lines "USER CODE BEGIN" and "USER CODE END"
• It is possible to change the uplink interval by sending a downlink command on channel 100 to the node. There a 4 possible intervals: 0c1E (30 sec), 0x3C (60 sec), 0x78 (120 sec) and 0xB4 (180 sec). When needed, change this in the code of LMIC-node.cpp.
• I also added the files gps.h and gps.cpp that I borrowed from sbiermann Lora-TTNMapper-ESP32 with a few changes.

In platfomio.ini the are also some additions: Added some new variables:

• HOME_LATITUDE, HOME_LONGITUDE Here you can fill in the coordinates of your starting point. Used i.c.w. MIN_DISTANCE.
• MIN_DISTANCE meters around your starting point where the mapper is not allowed to upload packages.
• GPS_DEVIATION To ignore small displacements, send only packages when the tracker moves.
• GPS_TX_PIN, GPS_RX_PIN The pin numbers of the gps module. Depends on the board type.
• a payload formatter for version 3.

Additional Features I have Added:

• Add the number of Satellites added to Lora Payload
• Battery Monitoring via ADC1_CHANNEL_3, ADC_ATTEN_DB_11 (GPIO 39) with vBatt added to the Lora Payload.
• Check vBat each processWork and light led2 to indicate Fully Charged Battery (4.2v)
• Dual Uplink Intervals: The device can send data at two different intervals (normal and long).Both Intervals are set via platfomio.ini
• ESP32 Processor speed reduced (setCpuFrequencyMhz(20);) to improve battery life of tracker.

Added new variables to platfomio.ini:

• DO_WORK_INTERVAL_SECONDS is the normal Lora interval (triggers processWork).
• DO_WORK_INTERVAL_LONG_SECONDS Is a longer interval (triggers processWorkLong) it Ignores MIN_DISTANCE & GPS_DEVIATION!!! (A heartbeat when the tracker is static for long periods)
• RESET_DO_WORK_INTERVAL_LONG... Reset DO_WORK_INTERVAL_LONG if location is sent by Normal Interval or comment out to have two completely Independant work Intervals