Android and arduino communication

"Android and arduino communication"








The only one needed is the permission to make the phone a USB host. The default device enumeration function in the library requires permission to all the attached devices which is not really feasible for use in a device selection list. To load the software on your Android device you will need to enable loading applications from unknown sources by following the instructions at this link. It costs about $5 on Amazon. Furthermore, modbus is a serial communication protocol, developed for industrial applications, open and easy to deploy and maintain. Android Studio - You will need to have this installed and setup. Opening a Connection First off, let us define the onClick method for the Begin button. You can find many of them in the Internet. After including the modbus library header at the beginning of the source code, I declared an integer array (named holdingRegs) that stores the modbus registers. I've included the source to this library in the application and made a few small changes to it: Added an InputStream and OutputStream implementation to better integrate the USB serial device with other Java classes. You could also follow this article to set up Android Studio on your computer. The sequel of this post is out! An activity can be described as a screen where the user interacts with the phone. Subsequently, I basically configure the digital Arduino pins with pinMode. RS32 and I? C as well. Arduino USB Cable USB OTG Cable - You will need this to connect the USB cable of the Arduino to the micro-USB port of the Smartphone. In the following post, Android project for smart home automation. So, at Activity01 we get five buttons, as below: Select “Open BT” button make the device’s own Bluetooth adapter (the Bluetooth radio) working. You could take a shot at fixing that problem, or just commend the guy that made the following video for his efforts. For those of you that are using one of the latest SimpleModbusSlave library, the Arduino code presented above needs some simple adjustments. The data received will be in the form of raw bytes. In this tutorial we just use the exact same code of Android and Arduino Hello World Tutorial. Closing the connection To close the connection, just close the SerialPort. I personally suggest you to take a look at documentation in order to have a better idea on how this library works. This is done because any change to the UI can only happen on the UI thread. Let me know if you need any help get it running. It is a simple function call with bytes of data which needs to be sent as the argument. Joe Desbonnet has recorded video of his device communicating with an Arduino. You can check by yourself, it is really simple code piece already. Declare the Bluetooth permission(s) in your application’s AndroidManifest. A SerialPort is defined using the device as the connection as the arguments. If Bluetooth is not supported, you should gracefully disable any Bluetooth features. If the first IF condition is satisfied, and if the user has granted permission, initiate a connection for the device whose vendor ID matched our required vendor ID. INDIG0 to INDIG4 are served for digital inputs, OUTD0 to OUTD4 to digital outputs and AOUT0 for PWM. An android phone with a connected arduino uno board is way better option than using a rasberry. Then, in the file explorer of Android Studio, right-click the JAR and select "Add as Library". So, in the Arduino sketch we add code to read values from the analog sensor, cut off the outlier values to cut the noise for this specific sensor, and send the bytes with adk method write() MainActivity. In case data from any sensor is needed and if that isn't available on board a smartphone, any microcontroller can be used to read from that sensor and transmit the data to the phone. For step one(Part1), we have just made a little APP for Android, achieve simple bluetooth connection with Android. Step two: Android APP connect to Arduino by Bluetooth Bee. Yea, look at it. As you can see, it has an EditText widget for getting input from the user, buttons to start the connection, transmit the data, end the connection and clear the TextView. Agree to install the application and it will be loaded on your Android device. Here we used two Android phones which are SAMSUNG I7680 and Lenovo O3. It controls the way the app will function. The Program Flow This is the brief outline of how we will proceed. If you liked this article, please share it! Represents the interface for a Bluetooth socket (similar to a TCP Socket). Conclusion? This article has helped to show how an Arduino can talk to your Smartphone. Sending Data to the Device Sending data is relatively easy when compared to reading data from the device. Now hover on this line and an alert will pop up on the left like this: Click Create 'OnClick. I will be using an Uno R3. Since this Callback will be running as a background thread, it can't affect the UI directly. All you need is an inexpensive HC-05 Bluetooth module, your Arduino and an Android smartphone. If Bluetooth is supported, but disabled, you are able to request the user enable Bluetooth without leaving your application. You can also plot data from your Arduino. CALIBRATION BLUETOOTH COMMUNICATION Last updated on 2015-05-04 at 04. This tutorial will use one activity, the Main Activity, which will take the user's input to send to the Arduino and also display the received text. Check if your phone does using the USB Host Diagnostics App from the Play Store. Then, there should be a complete development environment like Eclipse on your PC. But is it really necessary. Instructables member Techbitar has created a simple Android app to control your Arduino over Bluetooth, using some simple buttons and sliders. If you follow the steps on the Instructables page, you can download the app and Arduino sketch, and be up and running in no time. Get the complete code at the end of this article. I expressly selected RS485 because Arduino-based microcontrollers are not ready for Ethernet yet (even though some examples still exist but without great success). Function code 16 writes into them whereas function code 3 read them. Before your application can communicate with Bluetooth, you should verify Bluetooth is supported on the device and make sure that it is enabled. The vendor ID for any Arduino is 0x2341 or 9025. For the Bata, we only need to use Activity01, DiscoveryActivity, ClientSocketActivity and ServerSocketActivity. Step one: Make a APP to Android which could communicate with other devices by bluetooth. By using this micro-controller and some magnetic wire strategically placed and this app as the interface, he was able to send data to his compass enabled HTC Desire. Describes the general characteristics and capabilities of a Bluetooth device. The uses for this are endless! More than one Arduino board could be connected to the bus though. Every activity has a onCreate() method which is the run when the activity is created. Oh, Is it a little boring in front of this? OK, let us see some code, really start from here. Watch the second half of the video from the overview for an example of using the project with a USB connection. Here is a summary of the classes you will need to create as below. It is a half-duplex, 2-wires, low noise bus that allows high speeds and remote devices connection (up to 1200 meters). If you have the desire to look further into this check out his blog and instructions. Activities contain widgets like buttons, text fields, images, etc. When clicked, it should search for all connected devices and then check if the vendor ID of the Arduino matches that of a connected device. This will be defined in the OnClick method of the Send Button. Added a function to enumerate all the USB devices which are supported by the library. This APP allows Android connect to each other by bluetooth, so you need at least two Android devices for this demo. When you decided to do very complicated work with an arduino you will see that it is not enough. In fact, you only need to call the method without any parameter. With version V7 you need to modify the modbus_configure method call. My point is, these computers provide you more power than arduino. Among all the relevant libraries I had found, this was the only one which is still being updated. Arduino - Any version will do. The Layout We will be using the same layout for both the USB App and the Bluetooth App. This is done so that the data is received as soon as possible. See this instructable for a quick start Coding on the Arduino side is small text strings which completely control what the Android mobile displays. In the setup section of the sketch, I call the modbus_configure function in order to configure the modbus with the following parameters: the baud rate, the ID of the slave (address), the transmit enable pin and the number of registers. Indeed, RS485 is a well known standard that has been widely used in the indus­trial con­text and in building automa­tion appli­ca­tions. Each USB slave device has a vendor and product ID which can be used to identify what drivers should be used for it. The recieved data is displayed in the TextView (the empty part below the buttons). The app is in Alpha stage still, so expect some minor glitches (although everything appears to be pretty stable). Although the usb-serial-for-android library does most of the work for you, you will still need to do things like add permission for USB host mode to your application manifest. Whatever code you want to run at the start must be placed inside it. Android Studio makes app development easier with its predictions and code generation. A full overview of Android development is beyond the scope of this guide, but if you want to learn about Android development check out these resources: For the USB communication, this project uses the usb-serial-for-android library which is a great wrapper around USB to serial communication for Arduino and common FTDI chips. ACTION_REQUEST_ENABLE)”, a dialog box will appear and request user permission to enable Bluetooth. If this is successful, open the SerialPort and set the parameters accordingly. It is pretty easy to set up and use. Raspberry is a mini computer with a few output ports. Arduino sketch Arduino sketch essentially uses SimpleSlaveModbus library (Tutorial on how to install a new Arduino library ). Run the Smart Shaker application (it will have a green star as an icon) and follow the instructions to make a drink. Bluetooth Permissions In order to use Bluetooth features in your application, you need to declare at least one of two Bluetooth permissions: BLUETOOTH and BLUETOOTH_ADMIN. Finally, in order to have an insight on the status of the communication channel, I used a red led that indicates when a modbus message is received and processed. In the loop of the sketch, I inserted a call to modbus_update specifying, as a first parameter, the reference to the array that stores the modbus registers. Android USB Development If you're interested in building your own Android applications which communicate with Arduno devices over the USB connection you can look at the source code for the Smart Shaker application included in the software download. It will also be helpful to familiarize yourself with Android's USB development documentation. Receiving data from the Device In the code fragment above, notice the line that says serialPort. We will have to re-encode it into a readable format like UTF-8. The USB OTG cable tells the Android device to enter USB host mode and supply power to the Arduino. You will have to do this for each button. This function will take care of the received modbus commands and will modify the registers accordingly in case of writing or reading requests. This is how you going to do this kind of connection , - Buy an otg cable for Android like this: Simply, I designed an app to switch a led on and off. Here's a very simple code to do that. I used SimpleModbusSlave version V7 library. The next part of the article will show how to connect using the popular Bluetooth HC05 Module. Represents an open server socket that listens for incoming requests (similar to a TCP ServerSocket). All of the Bluetooth APIs are available in the Android bluetooth package. To add this library to your project, download the latest JAR file from Github. I guess you all get ready, let’s see more details. A quick check to see if you device supports USB host mode would be to connect a USB keyboard to the USB OTG cable and connect it to your Android device. Do notice that reading from the device is asynchronous, meaning it will keep running in the background. Select “Yes” and the system will enable Bluetooth and focus will return to your application once the process completes (or fails). Represents the local Bluetooth adapter (Bluetooth radio) BluetoothDevice. I used modbus RTU. The nice feature of the Android multi touch panel I used is that it has many interfaces such as Ethernet, RS485. Note: As mentioned in the previous step, if you also have a Bluefruit EZ-link attached to your hardware make sure to disconnect it before using the USB connection. Main Components of an Android App There are 3 major files in an Android app: MainActivity. Also, if a broadcast for a device attach or detach is received, manually call the onClick methods for the Start and Stop buttons. This is accomplished by modifying the modbus slave library and inserting a couple of digitalWrites (set to HIGH or LOW whenever necessary). Now fire up the Arduino IDE and set up the Arduino to simply echo whatever it receives on the serial port. There is one Bluetooth adapter for the entire system, and your application can interact with it when it is open. Android for calculation and heavy data process stuff, arduino for physical outputs. This will automatically inject code for the onClick method in MainActivity. Here a reference of a Callback is passed to the read function so that it will automatically trigger when any incoming data is detected. The baud rate can be 300, 600, 1200, 2400, 4800, 9600, 14400, 19200, 28800, 38400, 57600, or 115200, but let us go with the standard 9600. At this point you will need something bigger like raspberry or beaglebone. There are a host of other files too but they are all linked together with the help of these three. To make the communication between Android and Arduino easy, we would like show you a new way that android interact with Arduino and other similar boards. Also on an Arduino Nano it might be necessary to disconnect the Vin power line to the Arduino so it is powered from USB instead of the power supply. Thanks Luis for letting me know. With power applied to your project hardware, connect the USB OTG cable to a USB mini or micro cable which is connected to your Arduino. For an Uno, the default parameters are 8 Data bits, 1 Stop bit, no parity bit and Flow Control is Off. The Application Manifest? In the manifest, state what extra permissions the app might require. What is raspberry pi. This IntentFilter will be triggered when any new device is attached. If you just want to take a look at the complete code. Then it is appended to the TextView using a custom method named tvAppend(). You will also need a USB on-the-go or OTG cable to connect to your Arduino. Feb 10, 2014, 11:22 pm by drmpf Reason. If you can use the keyboard on your device, chances are good it will work with USB host mode to communicate to an Arduino. It accepts more parameters than the previous library versions, namely: a pointer to the hardware serial interface the baudrate of the modbus connection the modbus byte format. If found, permission must be requested from the user. The app must auto-start. Even though the idea of this project could be applied in many fields, I chose to contextualize it in a typical smart home context: a touch display that dims lights, shows temperatures and bulbs statuses. Represents a remote Bluetooth device, query information such as its name, address, class, and bonding state. As you can see, this is quite a trivial example. Try sending some text and the same data will be echoed back! It is pretty easy to do that. The activity start an AsyncTask to set up the reading from Arduino in another thread, avoiding to lock the main UI thread. The remaining part of the sketch reads the analog values from pin A0 and A1, reads the digital values (remember we set those digital pin to INPUT_PULLUP) and finally writes the digital values of the switches. I tested out a few of them and finally settled on the UsbSerial library by Github user felHR85.