Skip to main content

RFID (RC522)

Wiring​

tip

Source files for this diagram are available here

Wiring diagram

In case the above image is unclear, here's an additional schematic of the wiring as to prevent confusion:

Wiring schematic

Code​

Installing required libraries​

In order to use the RFID reader with your Pico, you'll first need to install a module.

warning

For future reference, you should note down in your codebase's README.md the dependencies that your code requires.

  • Open Thonny and connect to your Pico.

  • In the shell at the bottom of the window, type in the following commands to connect to your Wi-Fi network, replacing SSID and PASSWORD with your network's name and password:

    import network
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)
    wlan.connect("SSID","PASSWORD")

  • Now, run the following commands to install the required package:

    import mip
    mip.install("github:AerospaceJam/examples2024/mfrc522/mfrc522.py")

Example code​

from mfrc522 import MFRC522
 
reader = MFRC522(spi_id=0,sck=6,miso=4,mosi=7,cs=5,rst=22)
 
def read_tag() -> int:
    reader.init()
    (stat, tag_type) = reader.request(reader.REQIDL)
    if stat == reader.OK:
        (stat, uid) = reader.SelectTagSN()
        if stat == reader.OK:
            card = int.from_bytes(bytes(uid),"little",False)
            return card
    print("Failed to find a card.")
    return -1

# ----- Example usage -----
# (for all of these examples, make sure a tag is on the reader)
# read_tag()
# > 123456789