w1temp

Measure temperature through DS18B20 sensor connected to 1wire to Raspberry PI with node.js

Instalation

npm install w1temp

Dependencies

W1 configuration:

1. at the end of file /boot/config.txt add dtoverlay=w1-gpio,gpiopin=<gpiopin> where <gpiopin> is pin where is connected w1 data channel
2. run modprobe w1-gpio && modprobe w1-therm (it can be at cron too: @reboot sudo modprobe w1-gpio && sudo modprobe w1-therm)

Methods

W1Temp.setGpioPower(gpioPinNumber)

Turn on any gpio pin as W1 power.

W1Temp.setGpioData(gpioPinNumber)

Set any gpio pin to use as W1 data channel (required root permissions).

W1Temp.getSensorsUids(masterBusId = 1)

Return Promise which returns list of available sensors uids, catch if fails. If you operate multiple 1wire buses on one host, masterBusId defines the 1wire bus to use.

W1Temp.getSensor(sensorUid, enablePolling = true, interval = 250, onlyIfChanged = true)

Return Promise which returns sensor instance, catch if fails. The enablePolling argument controls whether the sensor will emit change events by monitoring the sensor value in the background. Defaults to enabled.

<sensor_instance>.getTemperature()

Returns actual temperature on sensor.

<sensor_instance>.getTemperatureAsync()

Return Promise which returns temperature on sensor.

<sensor_instance>.on('change', callback(temp))

Event on change temperature.

Example

var W1Temp = require('w1temp');

// turn on gpio pin 13 as W1 power if you want to
W1Temp.setGpioPower(13);

// set gpio pin 6 to use as W1 data channel
// if is not set by instructions above (required root permissions)
W1Temp.setGpioData(6);

// print list of available sensors uids (ex.: [ '28-00000636a3e3' ])
W1Temp.getSensorsUids().then(function (sensorsUids) {
  console.log(sensorsUids);
});

// get instance of temperature sensor
W1Temp.getSensor('28-00000636a3e3').then(function (sensor) {

  // print actual temperature
  var temp = sensor.getTemperature();
  console.log('Actual temp:', temp, '°C');

  // print actual temperature on changed
  sensor.on('change', function (temp) {
    console.log('Temp changed:', temp, '°C');
  });

});