def fp_download():

    ## Reads image and download it

    ## Tries to initialize the sensor
    try:
        f = PyFingerprint('/dev/ttyUSB0', 57600, 0xFFFFFFFF, 0x00000000)

        if ( f.verifyPassword() == False ):
            raise ValueError('The given fingerprint sensor password is wrong!')

    except Exception as e:
        print('The fingerprint sensor could not be initialized!')
        print('Exception message: ' + str(e))
        exit(1)

    ## Gets some sensor information
    print('Currently stored templates: ' + str(f.getTemplateCount()))

    ## Tries to read image and download it
    try:
        print('Waiting for finger...')

        ## Wait that finger is read
        while ( f.readImage() == False ):
            pass

        print('Downloading image (this take a while)...')

        imageDestination =  tempfile.gettempdir() + '/fingerprint.bmp'
        f.downloadImage(imageDestination)

        print('The image was saved to "' + imageDestination + '".')

    except Exception as e:
        print('Operation failed!')
        print('Exception message: ' + str(e))
        exit(1)