UART Write String

For another device like a smartphone to use any of the Bluetooth “services” which the board has, it must first be paired with the board. Once paired, the other device may connect to the board and exchange data relating to many of the board’s features.

The Bluetooth UART service allows another device such as a smartphone to exchange any data it wants to with the board, in small chunks.

With the Bluetooth UART service running, this block allows a board to send data to a Bluetooth connected device.

bluetooth.uartWriteString("");

Example: Starting the Bluetooth UART service and then sending “HELLO” whenever button A is pressed and another device has connected over Bluetooth

let connected = 0;
bluetooth.onBluetoothConnected(() => {
    basic.showString("C");
    connected = 1;
});
bluetooth.onBluetoothDisconnected(() => {
    basic.showString("D");
    connected = 0;
});
input.onButtonPressed(Button.A, () => {
    if (connected == 1) {
        bluetooth.uartWriteString("HELLO");
    }
});

Video - UART service guessing game

Advanced

For more advanced information on the board Bluetooth UART service including information on using a smartphone, see the Lancaster University board runtime technical documentation

See also

About Bluetooth, board Bluetooth profile overview , board Bluetooth profile reference, Bluetooth on board resources, Bluetooth SIG

bluetooth