使用 RPi2 在 Python 中使用 RC522 和 USB SERIAL 读取标签 UID

Question

我有一个带有两个 RFID reader 的 RPi2 (Python 2.7)。一个 reader 是 USB SERIAL hex Gigatek MF7（连接到串行端口），另一个是 RFID-RC522（连接到 GPIO 引脚）。按照 pimylifeup.com/raspberry-pi-rfid-rc522 上的说明正确连接 RC522。 reader 都可以工作和读取标签，但对于同一标签，它们的输出字符串不同。

我知道数据结构（串行 ASCII）和波特率：9600,N,8,1，从 Gigatek 读取 - link。我的脚本从串行端口读取 12 个字符的字符串并从中提取 UID reply_rfid_1[1:9]:

#!/usr/bin/env python2
# -*- coding: utf-8 -*-

"""
Convenient python function to read RFID tags with GIGATEK MF7
    """

############################

#from collections import defaultdict
#import csv
import sys
import serial
import time
from datetime import datetime



# define variables
global value_rfid, reply_rfid, refTime



# assign values
refTime = datetime.now()



# open the serial port /dev/ttyUSB1 and check if the port is really open
rfid_port_1 = serial.Serial("/dev/ttyUSB1", 9600)    # omit if not in use
print 'rfid_read.py -> rfid reader on port', rfid_port_1.name
rfid_port_1.isOpen()



def Read_Tag():
    # define variables
    global value_rfid_1, reply_rfid_1, tag
    
    # read port
    while int((datetime.now()-refTime).seconds) < 5:
        if (rfid_port_1.inWaiting() > 0):
            reply_rfid_1 = rfid_port_1.read(12)
            value_rfid_1 = str(reply_rfid_1[1:9])
            tag = str(value_rfid_1)
            print 'rfid_read.py -> tag hex', tag
            tag = int(tag, 16)
            print 'rfid_read.py -> tag dec ', tag
            break
        else:
            tag = None
    return tag



def Output_Tag():
    if tag == None:
        print 'rfid_read.py -> no tag'



def Flush_Port():
    rfid_port_1.flushInput()        # Clear input buffer
    time.sleep(0.1)



Read_Tag()
Output_Tag()
Flush_Port()
exit()

要从 RC522 读取数据，我使用以下代码：

reader = SimpleMFRC522()

print("Hold a tag near the reader")

try:
    id, text = reader.read()
    print(id)
    print(text)

finally:
    GPIO.cleanup()

我可以确定来自 SERIAL reader 的字符串的长度和数字格式，但我不能为 RC522 做到这一点。我在这些页面上找到了一些关于这些库的信息 github.com/mxgxw/MFRC522-python, github.com/pimylifeup/MFRC522-python 但无法破译输出块的数据结构，我真的很感激在这件事上的一些帮助。

2019 年 1 月 7 日更新

如下所示是两个输出和 SPI 状态。

USB reader 的输出为 HEX 和 DEC 数字格式：

rfid_read.py -> rfid reader on port /dev/ttyUSB1
rfid_read.py -> tag hex AC8C5E0A
rfid_read.py -> tag dec  2894880266

RC522reader对于同一个TAG的输出是：

Hold a tag near the reader
44535950452

SPI状态：

pi@raspberrypi:~ $ lsmod | grep spi
spidev                 20480  0
spi_bcm2835            20480  0

Answer 1

我按照 raspberrypi-spy.co.uk/2018/02/rc522-rfid-tag-read-raspberry-pi using the library github.com/mxgxw/MFRC522-python 中的说明尝试了不同的方法。将此库用于我拥有的标签的输出 UID 是：

Card read UID: 86,209,188,187

而同一标签的GIGATEK MF7 reader的输出UID是：

hex: BBBCD156
dec: 3149713750

结论 11. 7. 2019 使用 MFRC522-python 库的输出是正确的，但翻转过来并且不是正确的数字格式：

BB BC D1 56 = 187 188 209 86

因此我修改了库文件附带的 Read.py 标签 UID 读取脚本，以像我想要的那样将输出转换为十进制：

86 209 188 187 -> 56 D1 BC BB -> 3149713750

工作脚本：

def Read_Tag(self):
    # read with MFRC522 on GPIO
    # define variables
    global value_rfid_2, reply_rfid_2, tag, refTime
        
    # assign values
    refTime = datetime.now()
        
    # Create an object of the class MFRC522
    MIFAREReader = MFRC522.MFRC522()
        
    # read port
    while int((datetime.now()-refTime).seconds) < 5:
        # Scan for cards    
        (status,TagType) = MIFAREReader.MFRC522_Request(MIFAREReader.PICC_REQIDL)
        
        # If a card is found
        if status == MIFAREReader.MI_OK:
            print "Card detected"
            
        # Get the UID of the card
        (status,uid) = MIFAREReader.MFRC522_Anticoll()
        
        # If we have the UID, continue
        if status == MIFAREReader.MI_OK:
        
            # Print UID
            print "tag UID: %s,%s,%s,%s" % (uid[0], uid[1], uid[2], uid[3])
            tag_endian = (uid[3], uid[2], uid[1], uid[0])
            print 'tag endian:', tag_endian
            tag_hex = hex(uid[3]), hex(uid[2]), hex(uid[1]), hex(uid[0])
            print 'tag hex:', tag_hex
            tag_str = str(hex(uid[3])[2:]), str(hex(uid[2])[2:]), str(hex(uid[1])[2:]), str(hex(uid[0])[2:])
            print 'tag string:', tag_str
            tag_str = str(hex(uid[3])[2:])+str(hex(uid[2])[2:])+str(hex(uid[1])[2:])+str(hex(uid[0])[2:])
            print 'tag hex string concatenated:', tag_str
            tag = int(tag_str, 16)
            print 'tag dec:', tag
                
            # This is the default key for authentication
            key = [0xFF,0xFF,0xFF,0xFF,0xFF,0xFF]
               
            # Select the scanned tag
            MIFAREReader.MFRC522_SelectTag(uid)
        
            # Authenticate
            status = MIFAREReader.MFRC522_Auth(MIFAREReader.PICC_AUTHENT1A, 8, key, uid)
        
            # Check if authenticated
            if status == MIFAREReader.MI_OK:
                MIFAREReader.MFRC522_Read(8)
                MIFAREReader.MFRC522_StopCrypto1()
            else:
                print "Authentication error"
                
    GPIO.cleanup()      # Clear input buffer
    time.sleep(0.1)
    return tag

使用 RPi2 在 Python 中使用 RC522 和 USB SERIAL 读取标签 UID

Reading tags UID with RC522 and USB SERIAL in Python with RPi2

python

raspberry-pi2

gpio

rfid

uid