Project 10: RFID RC522 Module

Component Knowledge

Radio frequency identification, the card reader is composed of a radio frequency module and a high-level magnetic field. The Tag transponder is a sensing device, which doesn’t contain a battery. It only contains tiny integrated circuit chips and media for storing data and antennas for receiving and transmitting signals.

To read the data in the tag, first put it into the reading range of the card reader. The reader will generate a magnetic field, which can produce electricity according to Lenz’s law, then the RFID tag will supply power, thereby activating the device.

image40

Control Pins

Use IIC communication

SDA

SDA

SCL

SCL

Project 10.1 Open the Door

Open the folder where the mfrc522_config.py , soft_iic.py and mfrc522_i2c.py are located

Open“Thonny”，click“This computer”→“D:”→“2. Python Projects”→“pj10_rc522_RFID”. Select “mfrc522_config.py”, right-click your mouse to select “\ Upload to /\ ”，wait for “mfrc522_config.py” to be uploaded to ESP32; and select “soft_iic.py”, right-click your mouse to select “\ Upload to /\ ”，wait for “soft_iic.py” to be uploaded to ESP32; and then select “mfrc522_i2c.py”, right-click your mouse to select “\ Upload to /\ ”，wait for “mfrc522_i2c.py” to be uploaded to ESP32.

image41

image42

image43

The saved name are mfrc522_config.py , soft_iic.py and mfrc522_i2c.py.

image44

Test Code

from machine import Pin, PWM,I2C, Pin
import time
from mfrc522_i2c import mfrc522


pwm = PWM(Pin(13))
pwm.freq(50)
button1 = Pin(16, Pin.IN, Pin.PULL_UP)
#i2c config
addr = 0x28
scl = 22
sda = 21

rc522 = mfrc522(scl, sda, addr)
rc522.PCD_Init()
rc522.ShowReaderDetails()            # Show details of PCD - MFRC522 Card Reader details

data = 0

while True:
    if rc522.PICC_IsNewCardPresent():
        #print("Is new card present!")
        if rc522.PICC_ReadCardSerial() == True:
            print("Card UID:")
            #print(rc522.uid.uidByte[0 : rc522.uid.size])
            for i in rc522.uid.uidByte[0 : rc522.uid.size]:
                data = data + i
        print(data)
        if(data == 510):
            pwm.duty(128)
            print("open")
        else:
            print("error")
        data = 0
    btnVal1 = button1.value()
    if(btnVal1 == 0):
        pwm.duty(25)
        print("close")
    time.sleep(1)

Test Result

Close the provided card to the RFID induction area, the door will turn and open, and the shell shows “open”. Click button 1 and the door turns and closes. However, when swiping another blue induction block, the shell shows “Error”.

image45