5MM - 4 Legs RGB LED

Pin Connect

1. #!/usr/bin/python3  
    #Controlling a RGB LED with built in PWM.  
    #Mostly copied from GPIO PWM example:  
    #http://code.google.com/p/raspberry-gpio-python/wiki/PWM  
      
    import time  
    import RPi.GPIO as GPIO  
    import math  
      
      
    GPIO.setmode(GPIO.BOARD)  
    red = 12 #pin numbers to match LED legs  
    green = 16  
    blue = 18  
      
    GPIO.setup(red, GPIO.OUT) #setup all the pins  
    GPIO.setup(green, GPIO.OUT)  
    GPIO.setup(blue, GPIO.OUT)  
      
    Freq = 100 #Hz  
      
    #setup all the colours  
    RED = GPIO.PWM(red, Freq) #Pin, frequency  
    RED.start(0) #Initial duty cycle of 0, so off  
    GREEN = GPIO.PWM(green, Freq)    
    GREEN.start(0)   
    BLUE = GPIO.PWM(blue, Freq)  
    BLUE.start(0)  
      
    def colour(R, G, B, on_time):  
      #colour brightness range is 0-100  
      RED.ChangeDutyCycle(R)  
      GREEN.ChangeDutyCycle(G)  
      BLUE.ChangeDutyCycle(B)  
      time.sleep(on_time)  
      
      #turn everything off  
      RED.ChangeDutyCycle(0)  
      GREEN.ChangeDutyCycle(0)  
      BLUE.ChangeDutyCycle(0)  
      
    def PosSinWave(amplitude, angle, frequency):  
      #angle in degrees  
      #creates a positive sin wave between 0 and amplitude*2  
      return amplitude + (amplitude * math.sin(math.radians(angle)*frequency) )  
      
    try:  
        
      while 1:  
        for i in range(0, 720, 5):  
          colour( PosSinWave(50, i, 0.5),  
              PosSinWave(50, i, 1),  
              PosSinWave(50, i, 2),  
              0.1 )  
          
    except KeyboardInterrupt:  
      pass  
      
    #Stop all the PWM objects  
    RED.stop()  
    GREEN.stop()  
    BLUE.stop()  
      
    #Tidy up and remaining connections.  
    GPIO.cleanup()