Differences

This shows you the differences between two versions of the page.

--- pico_with_rfid-rcs522 [2026/09/01 21:43] – [Practical Example] walkeradmin
+++ pico_with_rfid-rcs522 [2026/09/01 21:53] (current) – [Some test Python Scripts] walkeradmin
@@ Line 92: / Line 92: @@
 ----
 ==== Some test Python Scripts ====
+\\
+<color #ed1c24>*****NOTE THE DRIVER ONLY WORKS WITH 4 BYTE UID TAGS AT THIS TIME, WE ARE LOOKING FOR AN UPDATED DRIVER*****</color>
+\\
 \\
 We will start with two scripts.
@@ Line 246: / Line 249: @@
 \\
 If you used the same GPIO Pins that we used in this example to connect the RFID Reader/Writer, then the pins for the LEDs above will be free.
+\\
+\\
+If you want to plug in the LEDs, then <color #ed1c24>see this wiki page</color> [[traffic_light_leds_using_array|here]] and use the code to test your LEDs (you should see a traffic light sequence).
+\\
+\\
+----
+==== The Python Code ====
+\\
+Below is the Python code we will use for this example, it's an expanded version of the rfid_read.py that we used earlier.
+\\
+\\
+What the code does is very simple.
+Reads the tag.
+Gets the value RED, AMBER or GREEN.
+Uses an if, elseif loop to turn on the corresponding LED (and turn the other off).
+Here is the code, save it to your Pico as rfidled.py.
+<code:python | download>
+from mfrc522 import SimpleMFRC522
+import time
+from machine import Pin
+# Define GPIO pins for the LEDs
+RED = Pin(2, Pin.OUT)
+AMBER = Pin(6, Pin.OUT)
+GREEN = Pin(10, Pin.OUT)
+# Put them in an array
+lights = [RED, AMBER, GREEN]
+# Set the GPIO pins being used
+reader = SimpleMFRC522(spi_id=0,sck=18,miso=16,mosi=19,cs=17,rst=9)
+# Function to turn off all LEDs
+def all_off():
+    for light in lights:
+        light.off()
+# Read the RFID card/tag/sticker
+def read():
+    print("Reading...Please place the card...")  # print a message telling the user to tap the card.
+    id, text = reader.read()   # read in two fields from the tag, id and text.
+    print("ID: %s\nText: %s" % (id,text))   # print the result in Thonny
+#   return id, text
+    return text.strip()  # this returns the contents of 'text' to the calling code, but strips off any crap like spaces.
+                         # Even if the tag is short (red) you still get 16 chars back from the read, so we need to strip of what is not required.
+# Call function 'all_off' to turn off all LEDs
+all_off()
+# Start a loop (forever)
+while True:
+    tag = read() #c all the function def read() and store the result in the varable tag
+    print ("the scanned colour is =", tag)  #print the contents of the variable tag
+    # Ched the read tag colour, turn off all LEDs then turn on the corresponding one. If no tags match, nothing happens.
+    if tag == "RED":
+        all_off()
+        RED.on()
+    elif tag == "AMBER":
+        all_off()
+        AMBER.on()
+    elif tag == "GREEN":
+        all_off()
+        GREEN.on()
+    time.sleep(1) # The delay is to stop the tag being read multiple times per second.
+</code>
+Run the code, if you have wired your LEDs correctly, and programmed your tags, each LED will come on with each Tag scan.
+\\
+\\
+----