First Steps with Tessel

tessel-climate-parse.js

// Libraries
var climate = require( 'climate-si7020' );
var parse = require( 'parse' ).Parse;
var tessel = require( 'tessel' );
var wifi = require( 'wifi-cc3000' );

// Constants
var PARSE_APP = '_YOUR_APP_KEY_';
var PARSE_KEY = '_YOUR_JAVASCRIPT_KEY_';

// Parse objects
var Temperature = parse.Object.extend( 'Temperature' );                    

// Use port
var port = climate.use( tessel.port['A'] );

// Initialize Parse library
// Note Tessel bug requiring change to Parse module
// https://github.com/tessel/runtime/issues/429
parse.initialize( PARSE_APP, PARSE_KEY );    

// Port is ready
port.on( 'ready', function () {
  console.log( 'Connected to si7020.' );

  // Queue execution of port access
  setImmediate( function loop() {
    // Read Farenheit temperature
    port.readTemperature( 'f', function( err, temperature ) {
      var storage = null;

      // Store in cloud if wireless
      if( wifi.isConnected() ) 
      {    
        // New Parse object
        // Values
        // Save
        storage = new Temperature();
        storage.set( 'fahrenheit', temperature );
        storage.set( 'celcius', ( temperature - 32 ) / 1.8 );
        storage.save( null, {
          success: function( result ) {
            console.log( 'Saved: ' + result.id );
          },
          error: function( result, error ) {
            console.log( error.message );
          }
        } );
      }

      // Log to console
      console.log( 'Temperature: ' + temperature.toFixed( 4 ) + 'F' );
            
      // Wait and do it again
      setTimeout( loop, 1000 );
    } );
  } );
} );

// Error accessing port
port.on( 'error', function( err ) {
  console.log( 'error connecting module', err );
} );    

tessel-climate.js

// Libraries
var climate = require( 'climate-si7020' );
var tessel = require( 'tessel' );

// Use port
var port = climate.use( tessel.port['A'] );

// Port is ready
port.on( 'ready', function () {
  console.log( 'Connected to si7020.' );

  // Queue execution of port access
  setImmediate( function loop() {
    // Read Farenheit temperature
    port.readTemperature( 'f', function( err, temperature ) {
      // Read relative humidity
      port.readHumidity( function( err, humidity ) {
        console.log(
          'Degrees: ', temperature.toFixed( 4 ) + 'F ', 
          'Humidity: ', humidity.toFixed( 4 ) + '%RH'
        );                
                
        // Wait and do it again
        setTimeout( loop, 1000 );                
      } );
    } );
  } );
} );

// Error accessing port
port.on( 'error', function( err ) {
  console.log( 'error connecting module', err );
} );    

tessel-climate.rest.js

// Libraries
var climate = require( 'climate-si7020' );
var https = require( 'https' );
var tessel = require( 'tessel' );
var wifi = require( 'wifi-cc3000' );

// Constants
var PARSE_APP = '_YOUR_APP_KEY_';
var PARSE_KEY = '_YOUR_REST_KEY_';

// Device port
var port = climate.use( tessel.port['A'] );

// Port is ready
port.on( 'ready', function () {
  console.log( 'Connected to si7020.' );

  // Queue execution of port access
  setImmediate( function loop() {
    // Read Farenheit temperature
    port.readTemperature( 'f', function( err, temperature ) {
      var options = null;
      var request = null;
            
      // Store in cloud if wireless
      if( wifi.isConnected() ) 
      {    
        options = {
          headers: {
            'Content-Type': 'application/json',
            'X-Parse-Application-Id': PARSE_APP,
            'X-Parse-REST-API-Key': PARSE_KEY  
          },
          hostname: 'api.parse.com',
          method: 'POST',                    
          path: '/1/classes/Temperature',                    
          port: 443
        };
                
        // Make request
        request = https.request( options, function( response ) {
          // Got a response
          response.on( 'data', function( data ) {
            console.log( data.toString().trim() );
          } );
        } );
        request.write( JSON.stringify( {
          fahrenheit: temperature,
          celcius: ( temperature - 32 ) / 1.8
        } ) );
        request.end();
                
        // Handle HTTPS error
        request.on( 'error', function( err ) {
          console.error( err );
        } );
      }

      // Log to console
      console.log( 'Temperature: ' + temperature.toFixed( 4 ) + 'F' );
            
      // Wait and do it again
      setTimeout( loop, 30000 );
    } );
  } );
} );

// Error accessing port
port.on( 'error', function( err ) {
  console.log( 'error connecting module', err );
} );    

tessel-led.js

// Libraries
var tessel = require( 'tessel' );

// GPIO access
var gpio = tessel.port['GPIO'];

// LED
var led = gpio.pin['G3'];

// Manage state
var led_state = false;

// Set off initially
led.output( led_state );

// Queue to start sampling
setImmediate( function loop() {
  // Switch LED state
  led_state = !led_state;
    
  // Send state to pin
  led.write( led_state );

  // Do it again
  setTimeout( loop, 1000 );
} );

tessel-thermistor-parse.js

// Libraries
var parse = require( 'parse' ).Parse;
var tessel = require( 'tessel' );
var wifi = require( 'wifi-cc3000' );

// Thermistor constants
var ANALOG_STEPS = 1023.0;
var B_THERM = 3977.0;
var T_THERM = 298.15;
var RESISTOR = 10000.0;
var THERMISTOR_OHM = 10000.0;
var VOLTAGE = 3.3;

// Parse.com constants
var PARSE_APP = '_YOUR_APP_KEY_';
var PARSE_KEY = '_YOUR_JAVASCRIPT_KEY_';

// Parse objects
var Temperature = parse.Object.extend( 'Temperature' );                    

// Initialize Parse library
// Note Tessel bug requiring change to Parse module
// https://github.com/tessel/runtime/issues/429
parse.initialize( PARSE_APP, PARSE_KEY );    

// GPIO access
var gpio = tessel.port['GPIO'];

// Thermistor
var thermistor = gpio.pin['A5'];

// Queue to start sampling
setImmediate( function loop() {
  var analog = null;
  var celcius = null;
  var fahrenheit = null;
  var storage = null;
    
  // Analog reading
  // Resulting range is zero to one
  analog = thermistor.read();
    
  // Voltage to temperature values
  // Multiply by 10-bit steps
  celcius = temperature( analog * ANALOG_STEPS );
  fahrenheit = celcius * 1.80 + 32.0;
        
  // Store in cloud if wireless
  if( wifi.isConnected() ) 
  {    
    // New Parse object
    // Values
    // Save
    storage = new Temperature();
    storage.set( 'fahrenheit', farenheit );
    storage.set( 'celcius', celcius );
    storage.save( null, {
      success: function( result ) {
        console.log( 'Saved: ' + result.id );
      },
      error: function( result, error ) {
        console.log( error.message );
      }
    } );
  }    
    
  // Show the value
  console.log( fahrenheit );
    
  // Do it again
  setTimeout( loop, 1000 );
} );

// Calculate celcius temperature
function temperature( analog ) 
{
  var kelvin = 0.0;
  var l_therm = 0.0;
  var r_therm = 0.0;    
  var v_out = 0.0;

  // Thermistor calculations
  v_out = VOLTAGE * analog / ANALOG_STEPS;
  r_therm = ( RESISTOR * VOLTAGE / v_out ) - RESISTOR;
  
  l_therm = Math.log( THERMISTOR_OHM / r_therm );
  kelvin = ( T_THERM * B_THERM ) / ( B_THERM - T_THERM * l_therm );    

  // Celcius value
  return kelvin - 273.15;
}

tessel-thermistor-rest.js

// Libraries
var https = require( 'https' );
var tessel = require( 'tessel' );
var wifi = require( 'wifi-cc3000' );

// Thermistor constants
var ANALOG_STEPS = 1023.0;
var B_THERM = 3977.0;
var T_THERM = 298.15;
var RESISTOR = 10000.0;
var THERMISTOR_OHM = 10000.0;
var VOLTAGE = 3.3;

// Parse.com constants
var PARSE_APP = '_YOUR_APP_KEY_';
var PARSE_KEY = '_YOUR_JAVASCRIPT_KEY_';

// GPIO access
var gpio = tessel.port['GPIO'];

// Thermistor
var thermistor = gpio.pin['A5'];

// Queue to start sampling
setImmediate( function loop() {
  var analog = null;
  var celcius = null;
  var fahrenheit = null;
    
  // Analog reading
  // Resulting range is zero to one
  analog = thermistor.read();
    
  // Voltage to temperature values
  // Multiply by 10-bit steps
  celcius = temperature( analog * ANALOG_STEPS );
  fahrenheit = celcius * 1.80 + 32.0;
        
  // Store in cloud if wireless
  if( wifi.isConnected() ) 
  {    
    // HTTPS request options
    // Parse headers
    // Parse URL
    // Parse path
    options = {
      headers: {
        'Content-Type': 'application/json',
        'X-Parse-Application-Id': PARSE_APP,
        'X-Parse-REST-API-Key': PARSE_KEY  
      },
      hostname: 'api.parse.com',
      method: 'POST',                    
      path: '/1/classes/Temperature',                    
      port: 443
    };

    // Make request
    request = https.request( options, function( response ) {
      // Got a response
      response.on( 'data', function( data ) {
        console.log( data.toString().trim() );
      } );
    } );
        
    // Send data along with request
    request.write( JSON.stringify( {
      fahrenheit: fahrenheit,
      celcius: celcius
    } ) );
        
    // End the request phase
    request.end();

    // Handle HTTPS error
    request.on( 'error', function( err ) {
      console.error( err );
    } );
  }    
    
  // Show the value
  console.log( fahrenheit );
    
  // Do it again
  setTimeout( loop, 1000 );
} );

// Calculate celcius temperature
function temperature( analog ) 
{
  var kelvin = 0.0;
  var l_therm = 0.0;
  var r_therm = 0.0;    
  var v_out = 0.0;

  // Thermistor calculations
  v_out = VOLTAGE * analog / ANALOG_STEPS;
  r_therm = ( RESISTOR * VOLTAGE / v_out ) - RESISTOR;
  
  l_therm = Math.log( THERMISTOR_OHM / r_therm );
  kelvin = ( T_THERM * B_THERM ) / ( B_THERM - T_THERM * l_therm );    

  // Celcius value
  return kelvin - 273.15;
}

tessel-thermistor.js

// Library
var tessel = require( 'tessel' );

// Constants
var ANALOG_STEPS = 1023.0;
var B_THERM = 3977.0;
var T_THERM = 298.15;
var RESISTOR = 10000.0;
var THERMISTOR_OHM = 10000.0;
var VOLTAGE = 3.3;

// GPIO access
var gpio = tessel.port['GPIO'];

// Thermistor
var thermistor = gpio.pin['A5'];

// Queue to start sampling
setImmediate( function loop() {
  var analog = null;
  var celcius = null;
  var farenheit = null;
    
  // Analog reading
  // Resulting range is zero to one
  analog = thermistor.read();
    
  // Voltage to temperature values
  // Multiply by 10-bit steps
  celcius = temperature( analog * ANALOG_STEPS );
  fahrenheit = celcius * 1.80 + 32.0;
    
  // Show the value
  console.log( fahrenheit );
    
  // Do it again
  setTimeout( loop, 1000 );
} );

// Calculate celcius temperature
function temperature( analog ) 
{
  var kelvin = 0.0;
  var l_therm = 0.0;
  var r_therm = 0.0;    
  var v_out = 0.0;

  // Thermistor calculations
  v_out = VOLTAGE * analog / ANALOG_STEPS;
  r_therm = ( RESISTOR * VOLTAGE / v_out ) - RESISTOR;
  
  l_therm = Math.log( THERMISTOR_OHM / r_therm );
  kelvin = ( T_THERM * B_THERM ) / ( B_THERM - T_THERM * l_therm );    

  // Celcius value
  return kelvin - 273.15;
}