Code:

int main() {
    uchar i;

    DDRD = 32; // PD5 as output

    PORTD |= 32; // turn LED on

    wdt_enable(WDTO_1S); // enable 1s watchdog timer

    usbInit();

    usbDeviceDisconnect(); // enforce re-enumeration
    for(i = 0; i<250; i++) { // wait 500 ms
        wdt_reset(); // keep the watchdog happy
        _delay_ms(2);
    }
    usbDeviceConnect();

    sei(); // Enable interrupts after re-enumeration

    PORTD &= ~32; // turn LED off

    while(1) {
        wdt_reset(); // keep the watchdog happy
        usbPoll();
    }

    return 0;
}