EON Demo from sensor data using Arduino and Johnny-Five

You need to install Johnny-Five and PubNub to run the node.js code with Arduino.

$ npm install johnny-five

$ npm install pubnub@3.15.2

Note: This code sample won't work with PubNub SDK v4+, so make sure to install v3.x

Overview on Publishing from Hardware & Subscribing to Plot a Graph on Browser

Publishing the Sensor Data to PubNub

Once you get the data from the sensor, send the data to PubNub.

var pubnub = require('pubnub')({
  publish_key: 'YOUR_PUB_KEY',
  subscribe_key: 'YOUR_SUB_KEY'
});

var data = {
  'temperature': temp
};

pubnub.publish({
  channel: 'temperature-ds18b20',
  message: data,
});

Data Visualization with EON

The basic graph can be drawn with EON's chart() as it receives the data from PubNub.

Chart type can be specified with data.type. In this example, it is a simple line graph:

<div id="temp"></div>

var pubnub = PUBNUB.init({
  publish_key: 'YOUR_PUB_KEY',
  subscribe_key: 'YOUR_SUB_KEY'
});

eon.chart({
  channel: 'temperature-ds18b20',
  generate: {
    bindto: '#temp', 
    data: {
      type: 'line'
    }
  }
},
pubnub: pubnub,
transform: function(m) {
  return { eon: {
      temperature: m.temperature
    }}
  }
});

To customize the chart (e.g. changing line colors, adding labels, etc.), please refer C3.js docs.

Run the HTML File

For eaxmple, to view the temperature line graph, run /temperature/temperature.html file on local server:

$ python -m SimpleHTTPServer 8000

Then go to localhost:8000 on browser, and run temperature.html

Hardware Wiring

Temperature

The temperature data comes from a DS18B20 sensor, and it is published to PubNub.

When you are using Arduino with Johnny-Five, you need to install ConfigurableFirmata to your Arduino to be able to run the code. The code requires OneWire support using the ConfigurableFirmata.

Installing ConfigurableFirmata

1. Connect your Arduino to computer with a USB cable
2. On Arduino IDE, go to Sketch > Include Library > Manage Libraries
3. Search for "ConfigurableFirmata"
4. Click the result, then click Install
5. Go to File > Examples > ConfigurableFirmata
6. Upload the code to the device

Arduino Wiring

Run the Node.js to Get Temperature from the Sensor

Change directory to temperature/ and run temperature.js:

$ node temperature.js

Photoresistor (Ambient Light Sensor) with DS18B20

Both a photoresistor a temperature sensor and the same breadboard to send both values to PubNub together:

Potentiometer

For potentiometer, I am using a gauge chart, instead of line graph.

Define the chart type, gauge (also label, min/max, ect.) in the eon settings:

eon.chart({
  channel: 'potentiometer',
  generate: {
    bindto: '#pot',
    data: {
      type: 'gauge',
    },
    gauge: {
      label:{
        format: function(value, ratio){
          return value; //returning here the value, not in %
        },
      },
      min: 0,
      max: 1023
    },
  } ...

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DS18S20, Photoresistor, and Potentiometer in one breadboard