import RPi.GPIO as GPIO
import time
GPIO.setmode(GPIO.BCM)
RING_PIN = 18                 # pin for led
GPIO.setup(RING_PIN, GPIO.OUT)    # set ledpin as output



pwmRing = GPIO.PWM(RING_PIN, 60)
pwmRing.start(0)




while 1:

	for z in range(1, 30, 3):
		pwmRing.ChangeDutyCycle(z)
		time.sleep(0.1)
		print(z)
	for z in range(30, 1, -3):
		pwmRing.ChangeDutyCycle(z)
		time.sleep(0.1)
		print(z)