// 
#include "mbed.h"

Serial USB(USBTX, USBRX); // : declare USB communication defined by Mbed USB TX and RX lines

void char_received();

void init_USB()
{   // -- This function is the setup for the USB communication --
    // Function char_received() is attached to Rx interrupt.

    USB.baud(38400); // set initial baudrate to 38400
    
    USB.attach(&char_received);    // : attach function
}