Raspberry Pi Bluetooth LE Controller for WS2812B (NeoPixels)

After configuring the Raspberry Pi to use BLE, we're ready to load a program to our RFduino. But, first we need to prepare our computer to recognize the RFduino boards.

At the time of this writing the following instructions have been tested in the latest version of the Arduino IDE (1.6.5). With your RFduino disconnected from the computer where you'll be using the Arduino IDE to program the RFduino.

1. Download and install Arduino IDE v1.6.5 or newer for your Operating System (OSX, Windows, or Linux)
2. Edit the Arduino IDE Preferences/Settings, and under Additional Board Manager URLs add:
   http://rfduino.com/package_rfduino_index.json
3. Navigate to Tools > Board > Board Manager and scroll down to RFduino Boards by RFduino. Click and select install the RFduino library.
4. Double check that “RFduino” is one of the entries now under Tools > Board
5. Connect the RFduino DIP Module to the RFduino USB Shield by matching the Pinouts. Then proceed to connect it to the computer's USB port.
6. Restart the Arduino IDE and the connected RFduino should be available under Tools > Port otherwise you may need to install the FTDI drivers for your Operating System.

Having trouble? Consult the comprehensive Quick Start guide by the RFduino creators.

Now that we're able to program the RFduino, we can write the code that we'll upload to it!

The goal for the program on the RFduino is to receive messages from the Pi, process them, and use the sent values to change the colors of the RGB LED. We'll break down the development of the code into these 3 tasks.

Receiving Messages

The first step is to write the code that will allow the RFduino to receive messages from the Pi or any other BLE-capable device. The first thing we'll setup is to broadcast under the id “My BLE LED”, and to idle in low-power mode while a message is received.

As with every program written in the Arduino IDE, we want to define the setup() and loop() functions:

void setup() {
// this is the data we want to appear in the advertisement
RFduinoBLE.advertisementData = “My BLE LED”;
// Start the BLE stack
RFduinoBLE.begin();
}

void loop() {
// Switch to lower power mode
RFduino_ULPDelay(INFINITE);
}

The RFduino functions we've called are standard for any piece of code that we write using this neat board. In order to receive messages, we'll add the following 3 functions:

void RFduinoBLE_onConnect() {
// Debug message printed to Serial interface
Serial.println(“RFduino connected”);
}

void RFduinoBLE_onDisconnect() {
// Debug message printed to Serial interface
Serial.println(“RFduino disconnected”);

}

void RFduinoBLE_onReceive(char *data, int len) {
// Debug message printed to Serial interface
Serial.println(“Data received: “);
for(int i=0;i Serial.print(data[i]);
Serial.println();
Serial.println(data);
}

Now that we've examined the code, we're ready to upload it to our RFduino. To do this, connect the RFduino DIP Module and the RFduino USB Shield. Then proceed to connect the connected boards to the USB port of your computer.

After uploading this simple program to the RFduino, we can test the communication from/to the Raspberry Pi!

Step 6: Writing Data Interactively With Gatttool (Raspberry Pi)