GPIO Start Location | Python Fiddle

#http://www.raspberrypi.org/archives/tag/tutorial
#initialize
#import time
#import WiringPi as Wire
import RPI.GPIO as GPIO

#Setup Mode and Warnings
GPIO.setmode(GPIO.BOARD)
GPIO.setwarnings(False)

#GPIO Output Pin Setup and initial values
GPIO.setup(23, GPIO.OUT) # Step 
GPIO.setup(23, GPIO.OUT, initial=GPIO.LOW) #Setting Intial Step not to start until after goes High.
GPIO.setup(24, GPIO.OUT) # Direction -
GPIO.setup(24, GPIO.OUT, initial=GPIO.HIGH) #Setting Intial Direction to CW

#GPIO Input Pin Setup and intial values
GPIO.setup(12, GPIO.IN) #Hall Effect Sensor: Stays High (1) until hits magnet goes to Low(0)
GPIO.add_event_detect(12, GPIO.FALLING) #Addint detection for falling to Low (~0)

#Intilize
filterValue = 0 # 0 is initialized value
filterWheelIndex = ['sloc','wlen1','wlen2','wlen3'] # Filter wheel values
print filterWheelIndex(filterValue) 
startLocation()

#Start Location
def startLocation():
    i = 0
	if GPIO.event_detect(12):
        print ('Falling Edge has occurred after:' + i + ' revolutions!')
        #return to start location Code!
        return 1 
    else:
    	print ('Count: ' + i)
        i = i + 1

def cleanUp():
	GPIO.cleanup()
    return 'end'

Browser Version Not Supported

Due to Python Fiddle's reliance on advanced JavaScript techniques, older browsers might have problems running it correctly. Please download the latest version of your favourite browser.
Chrome 10+ Firefox 4+ Safari 5+
IE 10+

Let me try anyway!

Python Fiddle

Python Cloud IDE