import RPIO
import time
import sys
import getopt

# suppress warning
RPIO.setwarnings(False)

# Which RPIO Numbering you like to use
RPIO.setmode(RPIO.BCM)
# Set the used RPIO PORTs
# OUT
cs_port = 17
clk_port = 27
RPIO.setup(cs_port, RPIO.OUT)
RPIO.setup(clk_port, RPIO.OUT)
# IN
do_port = 22
RPIO.setup(do_port, RPIO.IN)

# Clock Time
clock_time = 0.001  # 1ms

# Global referenz valu
ref_voltage = 2.540

# runs
v_runs = 10


# Helper Function to set the bits
# set a bit to 1
def setBit(int_type, offset):
    mask = 1 << offset
    return (int_type | mask)


# set a bit to 0
def clearBit(int_type, offset):
    mask = ~(1 << offset)
    return (int_type & mask)


# get the real Voltage value from the extracted value
def getVolt(vvalue):
    # Value of the Voltage at the Pin 5 - Vref
    # Not real exact 5V in Raspberry!
    # Adjust to your real value!
    global ref_voltage
    # the ADC0831 has a 8bit resolution => 256 discrete values possible
    return_val = (vvalue * ref_voltage) / float(255)
    return return_val


# Read the Value from Pin 6 - DO
def read_meter(value):
    # start reading the MSB first
    offset = 7
    #to debug the binary value
    bin_string = ""

    # first Clock Cycle
    RPIO.output(clk_port, RPIO.HIGH)
    time.sleep(clock_time)
    RPIO.output(clk_port, RPIO.LOW)
    time.sleep(clock_time)
    #second Clock Cycle
    RPIO.output(clk_port, RPIO.HIGH)

    # Now we can start measurement
    for clock in range(8):
        time.sleep(clock_time)
        RPIO.output(clk_port, RPIO.LOW)
        # Read if HIGH or LOW and set the value
        if RPIO.input(do_port):
            bin_string = bin_string + "1"
            value = setBit(value, offset)
        else:
            bin_string = bin_string + "0"
            value = clearBit(value, offset)
        # debug the result
        # print "Port 22 => {0:5} :: bit offset {1}".format(str(RPIO.input(do_port)),offset)
        offset -= 1
        #
        time.sleep(clock_time)
        RPIO.output(clk_port, RPIO.HIGH)
    #Print the result
    print "Value => {0:10.4f} :: binFormat :: {1} :: Bin Value :: {2}".format(getVolt(value), bin_string, value)
    return getVolt(value)


def main(argv):
    global ref_voltage
    global v_runs
    try:
        opts, args = getopt.getopt(argv, "hv:r:", ["vref=", "runs="])
    except getopt.GetoptError:
        print sys.argv[0] + " -v <referenzvoltage> -r <runs> "
        sys.exit(2)
    for opt, arg in opts:
        if opt == '-h':
            print sys.argv[0] + " -v <referenzvoltage> -r <runs> "
            sys.exit()
        elif opt in ("-v", "--vref"):
            ref_voltage = float(arg)
        elif opt in ("-r", "--runs"):
            v_runs = int(arg)
    print "Referenz Voltage => {0:10.4f} :: Runs :: {1}".format(ref_voltage, v_runs)


if __name__ == "__main__":
    main(sys.argv[1:])


# init first time 
RPIO.output(cs_port, RPIO.HIGH)
RPIO.output(clk_port, RPIO.LOW)
time.sleep(clock_time)
RPIO.output(cs_port, RPIO.LOW)
RPIO.output(clk_port, RPIO.HIGH)
time.sleep(clock_time)
RPIO.output(cs_port, RPIO.HIGH)
RPIO.output(clk_port, RPIO.HIGH)

v_avg = 0.0

#read the values and get the average value as result
for clock in range(v_runs):
    # set the CS Line to LOW and wait 
    RPIO.output(cs_port, RPIO.LOW)
    time.sleep(clock_time)
    # set the clock to LOW as Starting value
    RPIO.output(clk_port, RPIO.LOW)
    # Read the DO output
    v_avg += read_meter(0)
    # End reading the DO Value
    RPIO.output(cs_port, RPIO.HIGH)
    time.sleep(clock_time)
    RPIO.output(clk_port, RPIO.LOW)

print "Total Value => {0:10.4f}".format(v_avg / float(v_runs))

#Set a defined Value for the next start
RPIO.output(cs_port, RPIO.HIGH)
RPIO.output(clk_port, RPIO.HIGH)