homebridge-nodemcu-relay

This script interfaces with homebridge to expose a relay to Apple's HomeKit, allowing you to integrate numerous devices into your smart home.

Requirements

• NodeMCU

• Relay Module

• Pin header cables

• Micro-USB cable

How-to

1. First, install the ArduinoJson library from the Library manager in the Arduino IDE, then follow this gist which walks you through how to flash a NodeMCU.

2. Assuming that you already have homebridge set up, the next thing you will have to do is install homebridge-http using the command:

npm install -g homebridge-http

3. Finally, update your config.json file following the example below, making sure to adapt it accordingly:

"accessories": [
    {
      "accessory": "Http",
      "name": "Lights",
      "on_url": "http://relay.local/setState?type=switch&value=1",
      "off_url": "http://relay.local/setState?type=switch&value=0",
      "http_method": "GET"
    }
]

Wiring

NodeMCU	Relay Module
3V3	VCC
GND	GND
D7	IN1

Available Features

As you can see from the config.json example above, the basic format of the HTTP request is the declaration of the mode type followed by the required state:

http://relay.local/setState?type=STRING_VALUE&value=INT_VALUE

Here is a table which shows you the available queries:

Name	Query	Description	Example Uses
Switch	/setState?type=switch	Will simply turn on/off the relay permanently as per the Home app.	Lights, Faucets, Fans
Momentary	/setState?type=momentary	Will activate the relay for a brief moment, then deactivate after the amount of time specified in the script.	Garages, Gates, Buzzers
Modulation	/setState?type=modulation	Will activate then deactivate the relay constantly for the amount of time specified in the script until turned off.	Lights, Misting systems
State	/status	Will return the currentState in JSON form as 0 or 1	N/A