In this example we will demonstrate how to communicate with a device (such as Arduino) using the Java low-level API to control an LED using the USB port.
We are not using the OpenDevice Specifications, so let’s start to simplification. It can be used to connect to any serial device (eg fax modem using AT commands) without necessarily it has the OpenDevice firmware. But all features of data conversion and protocol is in your hand (little more difficult).
Add "opendevice-connection-stream" dependency to pom.xml (see this, and change the artifactId)
Hardware
For this sample you need only a PC and Arduino (or compatible like one of EnergiaIDE).
Set up the Arduino
If you have already used Arduino before this then you can skip this step. This will setup the Arduino development environment on your computer which will allow you to upload code to your Arduino. Go to the Arduino website and choose your platform (Windows, Mac, or Linux) and follow their guide to installing the IDE.
Sources
import br.com.criativasoft.opendevice.connection.DeviceConnection; import br.com.criativasoft.opendevice.connection.StreamConnectionFactory; import br.com.criativasoft.opendevice.connection.message.Message; public class Blink { public static DeviceConnection connection; public static void main(String[] args) throws Exception { connection = StreamConnectionFactory.createUsb("/dev/ttyACM0"); // OBS.1 connection.connect(); while(true){ connection.send(SimpleMessage.ON); Thread.sleep(500); connection.send(SimpleMessage.OFF); Thread.sleep(500); } } }
Options
Mac OS X: /dev/tty.usbserial-A9007UX1
Raspberry Pi / Ubuntu: /dev/ttyACM0
Linux: /dev/ttyUSB0
Windows: COM3
Use: UsbConnection.listAvailablePortNames(); to list available ports
#define LED 13 void setup(){ Serial.begin(9600); pinMode(LED, OUTPUT); } void loop(){ if (Serial.available() > 0) { int value = Serial.read(); // read value Serial.print("READ:"); Serial.println(value); if(value == HIGH || value == LOW ){ digitalWrite(LED,value); } } }
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