Raspberry Pi 4指纹传感器初始化失败求助：数据包无有效头部

我为学业评估购买了一款Basic Fingerprint Sensor With Socket Header Cable。最初自己写的代码能让传感器正常工作，但不符合评估要求。和老师沟通后拿到了经测试可用的代码，一开始运行正常，但修改代码适配评估规格后，传感器彻底无法工作，始终输出以下错误：

The fingerprint sensor could not be initialized!
Exception message: The received packet do not begin with a valid header!

之后我尝试了更换代码、更换依赖包、更换树莓派设备、更换传感器，甚至重装RaspOS系统，问题都没有解决，求可行的排查思路。

以下是最初可用、现在却报错的代码：

#!/usr/bin/env python
# -*- coding: utf-8 -*-

#PyFingerprint
##Copyright (C) 2015 Bastian Raschke
#All rights reserved.

import tempfile
from pyfingerprint.pyfingerprint import PyFingerprint

## Reads image and download it
##

## Tries to initialize the sensor
try:
    f = PyFingerprint('/dev/ttyS0', 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 used templates: ' + str(f.getTemplateCount()) +'/'+ str(f.getStorageCapacity()))

## 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)

内容的提问来源于stack exchange，提问作者Epilox