Connect a Raspberry Pi to a KY-029 Dual Color LED

Series resistors are recommended, about 120 ohms should be just fine.

Parts Required

You can connect to the module using dupont style jumper wire. There is no reason this device will not work with any Raspberry Pi hardware that you have – in this example a Raspberry Pi 4 but you can use a Zero if you want a lower cost solution

Name		Link
Raspberry Pi 4		Aliexpress link Amazon Ebay
37 in one sensor kit		Aliexpress link Amazon link
Connecting cables		Aliexpress link Amazon Ebay

Schematic/Connection

I didn’t have 120 ohms resistors in fritzing, so they are 150 ohms. It still worked. I also saw no side effects with no resistors fitted but I would recommend fitting a couple for peace of mind.

Code Examples

Basic example in  thonny, running on the Raspberry Pi

import RPi.GPIO as GPIO
import time
   
GPIO.setmode(GPIO.BCM)
   
# Here the output pin is declared, to which the LEDs are connected.
RED_LED = 24
GREEN_LED = 23
GPIO.setup(RED_LED, GPIO.OUT, initial= GPIO.LOW)
GPIO.setup(GREEN_LED, GPIO.OUT, initial= GPIO.LOW)
   
print ("LED test [press CTRL+C to end test]")
  
# main program loop
try:
    while True:
        print("LED RED 2 seconds on")
        GPIO.output(RED_LED,GPIO.HIGH) #LED is turned on
        GPIO.output(GREEN_LED,GPIO.LOW) #LED is switched off
        time.sleep(2) # wait for 2 seconds
        print("LED GREEN 2 seconds on") 
        GPIO.output(RED_LED,GPIO.LOW) #LED is switched off
        GPIO.output(GREEN_LED,GPIO.HIGH) #LED is switched on
        time.sleep(2) #wait for two seconds
   
# clean up after the program has been terminated
except KeyboardInterrupt:
    GPIO.cleanup()

pwm example in  thonny, running on the Raspberry Pi

import random, time 
import RPi.GPIO as GPIO
  
GPIO.setmode(GPIO.BCM) 
 
# Here we declare the output pin to which the LEDs are connected.
RED_LED = 24
GREEN_LED = 23
  
# Set pins to output mode
GPIO.setup(RED_LED, GPIO.OUT) 
GPIO.setup(GREEN_LED, GPIO.OUT)
  
Freq = 100 #Hz
  
# The respective colors are initialized.
RED = GPIO.PWM(RED_LED, Freq) 
GREEN = GPIO.PWM(GREEN_LED, Freq)
RED.start(0)  
GREEN.start(0)
  
def LED_Color(Red, Green, pause):
    RED.ChangeDutyCycle(Red)
    GREEN.ChangeDutyCycle(Green)
    time.sleep(pause)
 
    RED.ChangeDutyCycle(0)
    GREEN.ChangeDutyCycle(0)
   
print ("LED test [press CTRL+C to end test]")
  
# Main program loop:
try:
    while True:
        for x in range(0,2):
            for y in range(0,2):
                print (x,y)
                for i in range(0,101):
                    LED_Color((x*i),(y*i),.02)
  

except KeyboardInterrupt:
    GPIO.cleanup()

REPL Output

N/A

Links

https://github.com/getelectronics/PIBits/tree/master/Sensor%20Kit/KY-029_2_Color