/homebridge-dht

Homebridge plugin for DHT22 Temperature / Humidity Sensors

Primary LanguageJavaScriptApache License 2.0Apache-2.0

homebridge-dht

Supports integration of a DHT11/DHT21/DHT22/DHT33/DHT44 Temperature/Humidity Sensor into hombridge via the pigpio library on a Raspberry PI. I have tried numerous other interface methods for the DHT22, and found that this was least problematic. Also includes optional reporting of the RaspBerry PI CPU Temperature. This latest version splits the temperature and humidity into separate sensors, so they are readable from the home screen icon.

Also support use of multiple DHT22's, see config.json fragment.

Installation

For detailed installation instructions, please see the instructable at http://www.instructables.com/id/RPIHomeBridge-TemperatureHumidity-Sensor/

Configuration - with RPI cpu temperature sensor, requires cputemp program ( Optional )

{
    "bridge": {
        "name": "Penny",
        "username": "CC:22:3D:E3:CD:33",
        "port": 51826,
        "pin": "031-45-154"
    },

    "description": "HomeBridge DHT22",

 "platforms": [],

   "accessories": [
	{ "accessory":        "Dht",
	  "name":             "cputemp",
	  "service":          "Temperature" },
	{ "accessory":        "Dht",
          "name":             "dht22",
    	  "name_temperature": "Temperature",
          "name_humidity":    "Humdity",
          "service":          "dht22" }
	]
}

Configuration - without cputemp

{
    "bridge": {
        "name": "Penny",
        "username": "CC:22:3D:E3:CD:33",
        "port": 51826,
        "pin": "031-45-154"
    },

    "description": "HomeBridge DHT22",

 "platforms": [],

   "accessories": [
	{ "accessory":        "Dht",
          "name":             "dht22",
    	  "name_temperature": "Temperature",
          "name_humidity":    "Humdity",
          "service":          "dht22" }
	]
}

or with multiple DHT22's

{ "accessory":   "Dht",
  "name":        "dht22 - indoor",
  "name_temperature": "Indoor Temperature",
  "name_humidity": "Indoor Humdity",
  "gpio":        "4",       
  "service":     "dht22" },
{ "accessory":   "Dht",
  "name":        "dht22 - outdoor",
  "name_temperature": "Outdoor Temperature",
  "name_humidity": "Outdoor Humdity",
  "gpio":        "2",   
  "service":     "dht22" }

Configuration Options

Optional parameters includes

  • dhtExec - Full command including path to read dht22 sensor. Not needed unless dht22 is installed in a location not on the path. Defaults to dht22 ie "dhtExec": "/usr/local/bin/dht22"

  • cputemp - Full command including path to read cpu temp sensor. Not needed unless cputemp is installed in a location not on the path. Defaults to cputemp ie "cputemp": "/usr/local/bin/cputemp"

  • gpio - Gpio pin to read for dht22 sensor. Defaults to 4 ie "gpio": "4"

  • name: descriptive name

  • name_temperature (optional): descriptive name for the temperature sensor

  • name_humidity (optional): descriptive name for the humidity sensor

Optional cputemp script - install in /usr/local/bin

#!/bin/bash
cpuTemp0=$(cat /sys/class/thermal/thermal_zone0/temp)
cpuTemp1=$(($cpuTemp0/1000))
cpuTemp2=$(($cpuTemp0/100))
cpuTempM=$(($cpuTemp2 % $cpuTemp1))

echo $cpuTemp1" C"
#echo GPU $(/opt/vc/bin/vcgencmd measure_temp)

ToDo

Stop using the external program call, and call the pigpio library directly using npm module instead.

Credits

rxseger - separate humidity sensor hector305 - Multiple sensor testing