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IoT Sensor Library

This JavaScript library is used to communicate with the IoT Sensor Development Kit.

In order to use this library, build a Cordova app that contains the BLE plugin or create a new application using the Evothings Workbench.

To use this library, place the libs/evothings/dialog-iotsensor folder in the root of your Evothings application or www folder (Cordova).

Make sure to also copy the easyble library to libs/evothings/easyble. You can find the latest version on the evothings-libraries repository.

Initialization & Connecting

Include the iotsensor.js file

<script src="libs/evothings/dialog-iotsensor/iotsensor.js"></script>

Create a new iotsensor object by specifying the project type (RAW or SFL) you are using.

// Device type we are connecting to, can either be RAW or SFL
var type = evothings.iotsensor.SFL;

// Create a new IoT Sensor SFL instance
var iotsensor = evothings.iotsensor.createInstance(type);

Now that we have created a new IoT Sensor instance, we can try to connect to the sensor using BLE. The library provides the option to automatically connect to the closest IoT Sensor available using the connectToClosestSensor(scanTime, callbackFun, disconnectFun) function.

// Scan for 3000ms
    console.log('We are connected!');
    console.log('Disconnect error: ' + error);

You can also connect to a device manually, see the documentation for more information.

        console.log('Device found: ' + + ' RSSI: ' + device.rssi);
            // We have an IoT Sensor, let's connect!
                    // Connected and device is ready
                    console.log('Disconnect error ' + error);

Device info & Sensor data

The IoT Sensor provides a features report to see which sensors are available and the firmware version of the device connected. It is good practice to use these options to determine the capabilities of the device.

console.log('IoT Sensor device info:'
             + '\n Device model:  ' + iotsensor.getDeviceModel()
             + '\n Firmware:      ' + iotsensor.getFirmwareString()
             + '\n Accelerometer: ' + iotsensor.isAccelerometerAvailable()
             + '\n Gyroscope:     ' + iotsensor.isGyroscopeAvailable()
             + '\n Magnetometer:  ' + iotsensor.isMagnetometerAvailable()
             + '\n Barometer:     ' + iotsensor.isBarometerAvailable()
             + '\n Temperature:   ' + iotsensor.isTemperatureAvailable()
             + '\n Humidity:      ' + iotsensor.isHumidityAvailable()
             + '\n Sensor Fusion: ' + iotsensor.isSflAvailable());

In order to receive data from one of the sensors, a callback function must be set. This function is called everytime new data is available from the sensor. Once the callback is set, the sensor can be enabled. Note that Sensor Fusion is not available in RAW projects.

// Set the accelerometer callback and turn on the accelerometer

function handleReply(data)
  console.log('Accelerometer: ' + 
              '\n x: ' + data.x + 
              '\n y: ' + data.y + 
              '\n z: ' + data.z);

Note: All data (except for Sensor Fusion) is automatically converted to the correct unit of measurement. Please refer to the documentation for more information


Using this JavaScript library the IoT Sensor can be configured to your liking. The settings of the device can be divided into three categories:

Basic configuration
    Used to configure the sensors
Sensor fusion
    Set the SFL coefficients to control the relative weight of accelerometer and magnetometer data
    Set calibration coefficients
    Set calibration control flags

For a complete overview of all available settings, refer to the documentation.

Basic configuration

It is good practice to read the basic configuration settings from the device on startup,
in case the settings in flash memory do not match the default settings specified in configuration.BASIC

The configuration.BASIC object is an array and contains eleven different settings to control the sensors. In order to set correct values in the device, refer to the enums object. These objects contain all possible values that can be written to the device. Currently there is no check build in to make sure you are not writing wrong values to the device.

// Change accelerometer range to 16g
iotsensor.configuration.BASIC.ACCELEROMETER_RANGE = iotsensor.enums.ACCELEROMETER_RANGE._16g;

// After changing a settings, set the basic configuration in device

// Optional - Store basic configuration in flash

// Optional - Retrieve new settings from device
      console.log('Settings: ' + data);

Sensor Fusion

Changing the Sensor Fusion coefficients works the same as changing the basic configuration:

// Change Beta A to 2000
iotsensor.configuration.SFL_COEF.BETA_A = 2000;

// Set basic configuration in device

// Retrieve sensor fusion coefficients from device
        console.log('Sfl coefficients: ' + data);


In order to change the calibration coefficients and calibration control flag settings, refer to the configuration.CAL_COEF and configuration.CAL_CONTROL object.

iotsensor.configuration.CAL_COEF.Q_FORMAT = 12;

// Set offset vector
iotsensor.configuration.OFFSET_VECTOR = new Int16Array([100, 100, 100]);

// Set matrix
iotsensor.configuration.MATRIX = [new Int16Array([100, 0, 0]), new Int16Array([0, 100, 0]), new Int16Array([0, 0, 100])];

// Set Calibration coefficients in device

// Retrieve calibration coefficients from device
        console.log('Calibration coefficients: ' + data);
// Set calibration control flag byte 2 (CONTROL_FLAG[0])
iotsensor.configuration.CAL_CONTROL.CONTROL_FLAGS[0] = 28 // 0011100

// Set calibration control flags in device

// Retrieve calibration control flags from device
        console.log('Calibration control ' + data);

To learn more about the different control flags, refer to the user manual on the Dialog customer support site.

The function storeCalibrationAndControl() stores all settings regarding Sensor Fusion and Calibration in flash memory.



When an error occurs or when there is a new update, the default error and status handler is called. The default handler outputs the error and status to the console as follows:

// Error
console.log(evothings.iotsensor.currentTime() + ' IoT Sensor error: ' + error);

// Status
console.log(evothings.iotsensor.currentTime() + ' IoT Sensor status: ' + status);

Both the error and status handler can be set to your liking:


function errorFun(error)
  console.log('ERROR: ' + error);

function statusFun(status)
  console.log('STATUS: ' + status);

In order to determine if a sensor is correctly turned ON the sensor status callback can be used. This function is called everytime a sensor receives a START command and sends a reply back to the device.

Note: If this callback function is not set, an error Callback function not set for COMMAND_ID 1 is returned every time a sensor is turned ON.


function handleReply(data)
  console.log('Sensor status: ' + data); // 1: On