Interfacing Android Nexus One with Arduino + BlueSmirf
Introduction
This article outlines a guide to interface your Android Nexus One with an Arduino board via a Bluetooth module, the BlueSmirf. This combination allows you to control your Arduino projects from your phone, enabling a variety of innovative applications.
Components
* **Android Nexus One:** Your smart device.
* **Arduino Board:** An Arduino board (Uno, Mega, etc.) serves as the microcontroller.
* **BlueSmirf:** A Bluetooth module (e.g., BlueSmirf Silver) facilitates wireless communication.
* **Connecting Wires:** Male-to-male jumper wires for connecting the BlueSmirf to the Arduino.
Hardware Setup
1. **Connect the BlueSmirf to Arduino:**
* **Power:** Connect the BlueSmirf’s VIN pin to Arduino’s 5V pin.
* **Ground:** Connect the BlueSmirf’s GND pin to Arduino’s GND pin.
* **TX/RX:** Connect the BlueSmirf’s TX pin to Arduino’s RX pin (and vice-versa) using jumper wires.
2. **Upload Code to Arduino:** Load the Arduino sketch that will receive data from the Android device. This code should define how the Arduino reacts to incoming commands and interacts with peripherals.
Android App Setup
1. **Install Android App:** Install an Android app that allows sending commands over Bluetooth. Some popular choices include:
* **Bluetooth Terminal:** Provides a basic command-line interface.
* **Arduino Bluetooth Controller:** Offers a more user-friendly interface.
2. **Pair Nexus One with BlueSmirf:** Enable Bluetooth on your Nexus One and pair it with the BlueSmirf module.
Software Communication
1. **Data Format:** Define the format in which your Android app will send data to the Arduino. This could be a simple text string, a byte array, or a specific protocol.
2. **Arduino Code:** Modify your Arduino sketch to read incoming data from the BlueSmirf. This data should be processed to control your peripherals.
Example Code
#### Arduino Code (Arduino IDE)
“`C++
#include
SoftwareSerial bluetooth(10, 11); // RX, TX
void setup() {
Serial.begin(9600);
bluetooth.begin(9600);
}
void loop() {
if (bluetooth.available() > 0) {
String command = bluetooth.readStringUntil(‘\n’);
Serial.print(“Received: “);
Serial.println(command);
if (command == “LED_ON”) {
digitalWrite(13, HIGH);
} else if (command == “LED_OFF”) {
digitalWrite(13, LOW);
}
}
}
“`
#### Output (Arduino Serial Monitor)
“`
Received: LED_ON
Received: LED_OFF
“`
#### Android App Code (Java)
“`Java
// … Code to connect to Bluetooth device …
OutputStream outputStream = bluetoothSocket.getOutputStream();
String command = “LED_ON”;
outputStream.write(command.getBytes());
outputStream.flush();
“`
### Applications
* **Home Automation:** Control lights, appliances, or other home devices from your phone.
* **Robotics:** Control robot movement, sensor readings, or actuator functions remotely.
* **Data Logging:** Collect sensor data from your Arduino and display it on your phone.
* **Interactive Games:** Create interactive games where your phone acts as a controller.
Troubleshooting
* **Bluetooth Connection:** Ensure that your phone is paired correctly with the BlueSmirf.
* **Arduino Code:** Verify that the code is uploaded correctly and that the baud rate matches between the Arduino and the Bluetooth module.
* **Android App:** Make sure the app is sending data in the correct format and that your Arduino code is handling it appropriately.
Conclusion
Interfacing your Nexus One with an Arduino board using the BlueSmirf provides a powerful way to bridge the gap between your smartphone and the physical world. This combination unlocks limitless possibilities for creating innovative projects, remote control applications, and more.