UART Write String

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

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

With the Bluetooth UART service running, this block allows a Calliope mini 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.onButtonEvent(Button.A, input.buttonEventValue(ButtonEvent.Down), () => {
    if (connected == 1) {
        bluetooth.uartWriteString("HELLO");
    }
});

Video - UART service guessing game

Advanced

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

UART Write String

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

Video - UART service guessing game

Advanced

See also