pwmLed.py

#Define Libraries
import RPi.GPIO as gpio
import time

gpio.setwarnings(False)

#Configuring GPIO
gpio.setmode(gpio.BOARD)
gpio.setup(38,gpio.OUT)
gpio.setup(40,gpio.OUT)

#Configure the pwm objects and initialize its value
pwmBlue = gpio.PWM(38,100)
pwmBlue.start(0)

pwmRed = gpio.PWM(40,100)
pwmRed.start(100)

#Create the dutycycle variables
dcBlue = 0
dcRed  = 100

#Loop infinite
while True:

    #increment gradually the luminosity
    pwmBlue.ChangeDutyCycle(dcBlue)
    time.sleep(0.05)
    dcBlue = dcBlue + 1
    if dcBlue == 100:
        dcBlue = 0

    #decrement gradually the luminosity
    pwmRed.ChangeDutyCycle(dcRed)
    time.sleep(0.05)
    dcRed = dcRed - 1
    if dcRed == 0:
        dcRed = 100

#End code
gpio.cleanup()
exit()