NOTE: Thos project is no longer under development.

My Current product for this uses the TTGO modules, source code here: https://github.com/leon-v/TTGO-ESP32-LoRa

MQTT-ESP8266-nRF24L01-Solar-Battery-I-O-Network

The primary intention of the network is to be solar powered and real time so i can sense someone walking down my driveway and get a message on my phone

And secondarily it will be low cost. The parts i select will be cheap.

This project consists of:

1. An ESP8266 with one nRF24L01+ module which will act as an MQTT router for nRF24L01+.

2. Multiple nRF24L01+ nodes with a PIC to translate the radio to usable signals including PWM, ADC, DAC, I/O and Interrupt for real time detection. These will be battery powered from an 18650 and solar panels. The PIC will use responsible for battery management. Configuration will be done via MQTT.

Each node will have a short name which will be part of the 32 bytes payload.

Packet format

Packet format will be dynamic width, up to 32 characters. With limits for each segment of 16 characters. E.g. name/sensor/vlaue tank1/level/1234.5678

All configuration (apart from the WiFi User / Pass and MQTT details) will be retained in the MQTT broker. MQTT topics:

Licence is Beerware:

Licenced under the Beerware Vwesion 42 https://en.wikipedia.org/wiki/Beerware

Enviroment

Notes on setting up bash shell

Install Ubuntu 18 from the Misrosoft store.

In a command prompt:

>bash
>$sudo apt install dos2unix make python libncurses5-dev libncursesw5-dev

>$sudo ln -sv /usr/bin/python3 /usr/bin/python





Encryption may be used to prevent noise from any other sensors. 
Encryption used is possibly TEA

void encrypt (uint32_t* v, uint32_t* k) { uint32_t v0=v[0], v1=v[1], sum=0, i; /* set up / uint32_t delta=0x9e3779b9; / a key schedule constant / uint32_t k0=k[0], k1=k[1], k2=k[2], k3=k[3]; / cache key / for (i=0; i < 32; i++) { / basic cycle start / sum += delta; v0 += ((v1<<4) + k0) ^ (v1 + sum) ^ ((v1>>5) + k1); v1 += ((v0<<4) + k2) ^ (v0 + sum) ^ ((v0>>5) + k3); } / end cycle */ v[0]=v0; v[1]=v1; }

void decrypt (uint32_t* v, uint32_t* k) { uint32_t v0=v[0], v1=v[1], sum=0xC6EF3720, i; /* set up / uint32_t delta=0x9e3779b9; / a key schedule constant / uint32_t k0=k[0], k1=k[1], k2=k[2], k3=k[3]; / cache key / for (i=0; i<32; i++) { / basic cycle start / v1 -= ((v0<<4) + k2) ^ (v0 + sum) ^ ((v0>>5) + k3); v0 -= ((v1<<4) + k0) ^ (v1 + sum) ^ ((v1>>5) + k1); sum -= delta; } / end cycle */ v[0]=v0; v[1]=v1; }