1.      Read DHT Sensor

This is final part. In this part the Arduino will send/ read the DHT sensor and display it on the app.

 Hardware setup for this part (continued from previous part)

Pin Layout              

Arduino Code

[ Arduino2Android_final_setup.ino code available on purchase ]

[DHT Library - DHT]

DHT Library needs to be installed before you strat using it.

How To Install a Arduino Library

Things to do on Android:

Arduino App

• Add the components as below:

• 1 HorizentalArranagment

• 1 Textbox

• Clock (this is a invisible component)

HorizentalArrangment properties

• Height = 10 pixel 

TextBox Properties

• Height = 100 pixel

• Width = 300 pixel

• MiultiLine = true

• TextAligment = Centre

• Enabled = False

• Rename = txtSensorData

 Clock

• TimerInterval = 50

Drag the components and connect them as shown below. Se the required properties.

Open the Block Editor and Drag and connect Blocks are shown below:

• Create two variables; buffer and incomingData and set text on both to blank

• Drag and connect the blocks as show below to create a Timer code. The code checks if there is a bluetooth connection. If connection is there its starts reading the sensor data into buffer variable till it read *.
• It then transfers the data  from buffer to incomingdata variable. The incomingData is display on the app textbox as text and Incoming variable is emptied to receive new Data.
• If the connection is not there it display “Connect Bluetooth to Re4ad Sensor” on the app textbox.  

This almost completes the tutorial for the Kit. Install the arduino code and test your App.

Android App - [MyApp Install File]

MIT App Inventor - [Source Code]  

Part 4 - Adding Blutooth Pair Option and Application Changes