ESP8266 / RMF95w LoRa Node

Introduction

This page describes the ESP8266 Sensor that was built for use in a LoRa network. The state of this sensor is: Work in progress

Still to be sorted out:

What DIO pin's need not to be connected to the ESP8266 MCU and what are not necessary.The minimum set of pins that need to be connected is found below. However, please keep in mind that in order to do anything smart with this "sensor", you have to connect physical sensor devices to the mcu so that it can report these value to the network
We need to find out what low-power options can be used for the ESP-8266 especially if we do not use its WiFi functions
Can we use WiFi functions together with the LoRa sensor, and will the ESP8266 be stable for a longer time.

Pin-out RFM95W transceiver

The following is the pin-out of the RFP95 chip. Of course if you choose to use a LoRabee or other type of adapter board you have to use thos pin settings.

Pin-out on HopeRF rfm95 shield:

	Top of LoRaBee (antenna)
DIO4		GND
DIO3		GND
DIO2		GND
DIO1		3.3V
DIO0		GND
MISO		GND
MOSI		RST
SCK		3.3V
NSS		3.3V
RST		3.3V

Wemos D1-mini pin-out

Following picture from the Wemos.cc site shows the pin definitions for the Wemos D1-mini (Click it to enlarge)

Connections Wemos D1-mini to RFM95

These connections must be made as a minimum to get the ESP8266 work with the RFM95 and the LMIC software. The software will probably also work on other ESP866 nodeMCU based boards, but pay attention as their pin layout might be different.

Wemos top	LMIC	ESP8266 pins	NOTEs
DIO5
DIO4
DIO3
DIO2	.dio[2]	D3, GPIO3	Probably leave open!
DIO1	.dio[1]	D2, GPIO4	Must be connected
DIO0	.dio[0]	D1, GPIO5	Must be connected
MISO		D6, GPIO12
MOSI		D7, GPIO13
SCK		D5, GPIO14, CLK
NSS	.nss	D8, GPIO15
RESET	.rst	D0, GPIO16	No interrupt support (which is OK)
		D3, GPIO0	D3 is used to select boot-up. Only works with UART connected and flashing. Probably leave open!
		D4, GPIO2	Free -- To be used for OneWire sensors

Temperature Sensor Node?

On the next page the connections are made to a DS18B temperature sensor.