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.
This block starts an event handler which in this case will run when something connects to your Calliope mini using Bluetooth.
bluetooth.onBluetoothConnected(() => {});You could use this event handler to display a letter “C” on the Calliope mini LED grid so you know you have a Bluetooth connection. Or you might want to send some data you’ve been accumulating to your smartphone as soon as it connects to your Calliope mini. Maybe you’ve been using the accelerometer in your Calliope mini to count your steps for example. Using this event handler you could send the accumulated step count to your phone when it establishes a Bluetooth connection.
bluetooth.onBluetoothConnected(() => {
basic.showString("C");
});About Bluetooth, Calliope mini Bluetooth profile overview , Calliope mini Bluetooth profile reference, Bluetooth on Calliope mini resources, Bluetooth SIG
bluetooth