"""

This is the "main" function of the program.

It will instantiate PyMata for communication with an Arduino micro-controller

and the command handlers class.

It will the start the HTTP server to communicate with Scratch 2.0

@return : This is the main loop and should never return

"""

# total number of pins on arduino board

total_pins_discovered = 0

# number of pins that are analog

number_of_analog_pins_discovered = 0

# make sure we have a log directory and if not, create it.

if not os.path.exists('log'):

os.makedirs('log')

# turn on logging

logging.basicConfig(filename='./log/s2a_fm_debugging.log', filemode='w', level=logging.DEBUG)

logging.info('s2a_fm version 1.5 Copyright(C) 2013-14 Alan Yorinks All Rights Reserved ')

print 's2a_fm version 1.5 Copyright(C) 2013-14 Alan Yorinks All Rights Reserved '

# get the com_port from the command line or default if none given

# if user specified the com port on the command line, use that when invoking PyMata,

# else use '/dev/ttyACM0'

if len(sys.argv) == 2:

com_port = str(sys.argv[1])

else:

com_port = '/dev/ttyACM0'

logging.info('com port = %s' % com_port)

try:

# instantiate PyMata

firmata = PyMata(com_port) # pragma: no cover

except Exception:

print 'Could not instantiate PyMata - is your Arduino plugged in?'

logging.exception('Could not instantiate PyMata - is your Arduino plugged in?')

logging.debug("Exiting s2a_fm")

return

# determine the total number of pins and the number of analog pins for the Arduino

# get the arduino analog pin map

# it will contain an entry for all the pins with non-analog set to firmata.IGNORE

firmata.analog_mapping_query()

capability_map = firmata.get_analog_mapping_request_results()

firmata.capability_query()

print "Please wait for Total Arduino Pin Discovery to complete. This can take up to 30 additional seconds."

# count the pins

for pin in capability_map:

total_pins_discovered += 1

# non analog pins will be marked as IGNORE

if pin != firmata.IGNORE:

number_of_analog_pins_discovered += 1

# log the number of pins found

logging.info('%d Total Pins and %d Analog Pins Found' % (total_pins_discovered, number_of_analog_pins_discovered))

# instantiate the command handler

scratch_command_handler = ScratchCommandHandlers(firmata, com_port, total_pins_discovered,

number_of_analog_pins_discovered)

# wait for a maximum of 30 seconds to retrieve the Arduino capability query

start_time = time.time()

pin_capability = firmata.get_capability_query_results()

while not pin_capability:

if time.time() - start_time > 30:

print ''

print "Could not determine pin capability - exiting."

firmata.close()

# keep sending out a capability query until there is a response

pin_capability = firmata.get_capability_query_results()

time.sleep(.1)

# we've got the capability, now build a dictionary with pin as the key and a list of all the capabilities

# for the pin as the key's value

pin_list = []

total_pins_discovered = 0

for entry in pin_capability:

# bump up pin counter each time IGNORE is found

if entry == firmata.IGNORE:

scratch_command_handler.pin_map[total_pins_discovered] = pin_list

total_pins_discovered += 1

pin_list = []

else:

pin_list.append(entry)

print "Arduino Total Pin Discovery completed in %d seconds" % (int(time.time() - start_time))

try:

# start the server passing it the handle to PyMata and the command handler.

scratch_http_server.start_server(firmata, scratch_command_handler)

except Exception:

logging.debug('Exception in s2a_fm.py %s' % str(Exception))

firmata.close()

return

except KeyboardInterrupt:

# give control back to the shell that started us

logging.info('s2a_fm.py: keyboard interrupt exception')

firmata.close()