python script to test kitsch bent board buttons

i2ctest.py

#!/usr/bin/python

PortAKeys = { 0x04: 'B', 0x08 : 'A', 0x10: 'R2', 0x20: 'R1', 0x40: 'X', 0x80: 'Y'}
PortBKeys = { 0x01 : 'Up', 0x02 : 'L1', 0x04 : 'L2', 0x08: 'Left', 0x10: 'Right', 0x20: 'Down', 0x40: 'Select', 0x80: 'Start' }

import smbus

I2C_DEV = 0x20      #7 bit address (will be left shifted to add the read write bit)
PULLUP_A = 0x0c
PULLUP_B = 0x0d

PORT_A = 0x12
PORT_B = 0x13

bus = smbus.SMBus(1)    # 0 = /dev/i2c-0 (port I2C0), 1 = /dev/i2c-1 (port I2C1)

def init_pullup(address):
    bus.write_byte_data(I2C_DEV, address, 0xFF)

def read_port(address):
    return bus.read_byte_data(I2C_DEV, address)

def getKeyNames(byte, dic):
    keys = ""
    for k,name in dic.iteritems():
        if k & byte == 0:
            keys += name + ' '
    return keys

init_pullup(PULLUP_A)
init_pullup(PULLUP_B)
oldA = 0
oldB = 0
while True:
    A, B = read_port(PORT_A), read_port(PORT_B)
    if A != oldA or B != oldB:
        keyNames = getKeyNames(A, PortAKeys) + " " + getKeyNames(B, PortBKeys)
        print "A: {:02x} B: {:02x} {}".format(255 - A, 255 - B, keyNames)
        oldA = A
        oldB = B