def list_devices():
    """Return a list of the supported devices connected  
    
    Returns:
        A list of string names of the devices supported which were found. Empty if no supported devices found
    """
    devices = []
    all_hids = hid.find_all_hid_devices()
    if all_hids:
        for index, device in enumerate(all_hids):
            for device_name,spec in device_specs.items():
                if device.vendor_id == spec.hid_id[0] and device.product_id == spec.hid_id[1]:
                    devices.append(device_name)                        
    return devices