#-------------------------------------------------------------------------------#
# Name:         23017-2port-io-s-v103.py					#
# Purpose:      23017 Input and Output Simple GUI V1.03 			#
# GPIO-Library: RPi.GPIO 0.5.3a							#
#										#
# Author:       Pridopia, James Clarke						#
# Website:      www.Pridopia.co.uk						#
#										#
# Created:      17/09/2013							#
#-------------------------------------------------------------------------------#

import smbus, sys, getopt, time, os

Bus = smbus.SMBus(1)

def Read(Addr, Reg):
	Ret = Bus.read_byte_data(Addr, Reg)
	Ret = str( '{:08b}'.format( Ret ) )
	return Ret

def Write(Addr, Reg, Data):
	Bus.write_byte_data(Addr, Reg, Data)
	return 1

def main():

	Write(0x21, 0x12, 0x00)					# Reset the GPIO Pins
	Write(0x21, 0x13, 0x00)

	Write(0x22, 0x12, 0x00)					# On both chips.
	Write(0x22, 0x13, 0x00)

	#Write(0x21, 0x03, 0xFF)					# Reset the IPOLB to invert the input ( Supposed to... )

	Write(0x21, 0x00, 0x00)					# Now reset all the IODIRA and IODIRB to 0x00
	Write(0x21, 0x01, 0x00)
	Write(0x22, 0x00, 0x00)
	Write(0x22, 0x01, 0x00)

	try:
	    while True:
		os.system("clear")
		Write(0x21, 0x13, 0xFF)
		A = Read(0x21, 0x13)				# The Input Address of the buttons ( We read directly from here )
		A = int(A, 2) ^ 0xFF
		A = '{:08b}'.format(A)
		Bin = Read(0x21, 0x13)				# The Output LED Address and Register.
		Bin2 = Bin					# Save a spare set of the data to be used later to write to the reg
		Bin = 255 - int(Bin, 2)				# Nice trick to reverse the Binary data E.g 0011 goes in, 1100 comes out
		Bin = '{:08b}'.format(Bin)			# Format the Binary so that it includes all leading zeros
		B1 = Bin[0]
		B2 = Bin[1]
		B3 = Bin[2]
		B4 = Bin[3]
		B5 = Bin[4]
		B6 = Bin[5]
		B7 = Bin[6]
		B8 = Bin[7]
		print("Input test for MCP23017")
		print("\nInput  Address: 0x21, Register 0x13" )
		print("Input : [%s] [%s] [%s] [%s] [%s] [%s] [%s] [%s]" % (A[7], A[6], A[5], A[4], A[3], A[2], A[1], A[0]) )
		print("\nOutput Address: 0x22, Register 0x13" )
		print("Output: [%s] [%s] [%s] [%s] [%s] [%s] [%s] [%s]" % (B8, B7, B6, B5, B4, B3, B2, B1) )
		Bin2 = 255 - int(Bin2, 2)
		Write(0x22, 0x12, Bin2 )
		time.sleep(0.12)

	except KeyboardInterrupt:
		sys.exit()

if __name__ == '__main__':
    main()