import time
import RPi.GPIO as GPIO

GPIO.setmode(GPIO.BCM)

PIN_CLK = 3 #2
PIN_DAT = 2 #3
PIN_CS  = 4
delay = 0.0000005

# pin setup done here
try:
    GPIO.setup(PIN_CLK,GPIO.OUT)
    GPIO.setup(PIN_DATA,GPIO.IN)
    GPIO.setup(PIN_CS,GPIO.OUT)                                                                                                    
    GPIO.output(PIN_CS,1)
    GPIO.output(PIN_CLK,1)
except:
    print "ERROR. Unable to setup the configuration requested"                                     

#wait some time to start
time.sleep(0.5)

print "GPIO configuration enabled"

def clockup():
    GPIO.output(PIN_CLK,1)
def clockdown():
    GPIO.output(PIN_CLK,0)

def readpos():
    GPIO.output(PIN_CS,0) #pulls low to start

    time.sleep(delay*2)
    data = [0]
    clockdown()
    
    for i in range(0,10); #bitcount):
        clockup() #375 ns between each
        data[i]<<=1  
        data[i]|=GPIO.input(PIN_DATA)
        clockdown()
    
    GPIO.output(PIN_CS,1) #pull high after finish
    return data

try:
    while(1):
        print readpos()
        time.sleep(0.001)
        #break
        
finally:
    print "cleaning up GPIO"
    GPIO.cleanup()