TTYSETDTR
case TTYSETDTR:
uint8 bit = op == TTYSETDTR ? MCR_DTR : MCR_RTS;
case TTYSETDTR:
uint8 bit = op == TTYSETDTR ? USB_CDC_CONTROL_SIGNAL_STATE_DTR
result &= tty->service_func(tty, TTYSETDTR, &dtr, sizeof(dtr));
result &= tty->service_func(tty, TTYSETDTR, &dtr, sizeof(dtr));