读卡器在移除RFID标签后关闭，直到程序重新启动后才会重新打开

Question

我正在尝试使用ACR122u NFC阅读器与NFC标签进行通信。程序启动良好，当一个标签连接时，它能够读取并执行标签上的所有所需操作。然而，一旦NFC标签被移除，读卡器就会关闭，直到程序重新启动才会打开。以下是我轮询读卡器的代码：

def CheckNFCCard():
    getUIDCommand = [0xFF, 0xCA, 0x00, 0x00, 0x00]
    turnOffBeepCommand = [0xFF, 0x00, 0x52, 0x00, 0x00]
    getDataCommand = [0xFF, 0xB0, 0x00, 0x07, 0x10]
    updateBlockCommandFirst=[0xFF, 0xD6, 0x00, 0x07, 0x04, 0x65, 0x6E, 0x75, 0x73]
    updateBlockCommandSecond=[0xFF, 0xD6, 0x00, 0x08, 0x04, 0x65, 0x64, 0xFE, 0x00]

  #get NFC reader
    r = readers()
    reader = r[0]
    #select reader, connect
    conn = reader.createConnection()
    while(True):
        print('NFC routine restart')
        try:
            conn.connect()
        except:
            time.sleep(1)
            continue
        #send hex command to turn off beeps on scan.
        conn.transmit(turnOffBeepCommand)

        #get data encoded on tag.
        data, sw1, sw2 = conn.transmit(getDataCommand)
        if (sw1, sw2) == (0x90, 0x0):
            print("Status: The operation completed.")

        #Turn decimal numbers into characters
        stringList = [chr(x) for x in data]
        #
        identifierString = ''.join(stringList)[2:6]
        if (identifierString == "used"):
            pub.sendMessage('NFCDetected', arg1='used')
        elif (identifierString == "new_"):
            data, sw1, sw2 = conn.transmit(updateBlockCommandFirst)
            if (sw1, sw2) == (0x90, 0x0):
                conn.transmit(updateBlockCommandSecond)
            Thread(target=pub.sendMessage, args=('NFCDetected',), kwargs={'new' : arg1}).Start()
        time.sleep(1)
        continue

循环继续按预期运行，但读卡器已关闭，不会再次连接

任何帮助都将不胜感激