<----SKIPPED LINES---->




      *SERVO_CONNECTION, read_timeout=7,
      error_pin=messageboard.GPIO_ERROR_ARDUINO_SERVO_CONNECTION, to_parent_q=to_parent_q,
      read_format='l', write_format='ff???', name='Servo')
  link.Open()

  last_flight = {}
  last_angles = (0, 0)
  flight, json_desc_dict, configuration, additional_attr = InitialMessageValues(
      to_arduino_q)
  next_read = 0
  next_write = 0
  now = GetNow(json_desc_dict, additional_attr)

  while not shutdown.value:
    if not to_arduino_q.empty():
      flight, json_desc_dict, configuration, additional_attr = to_arduino_q.get(
          block=False)

      if 'test_servos' in configuration:
        messageboard.RemoveSetting(configuration, 'test_servos')

        link.Write((0, 0, *LASER_RGB_OFF))
        time.sleep(1)
        link.Write((90, 0, *LASER_RED))
        time.sleep(1)
        link.Write((180, 0, *LASER_GREEN))
        time.sleep(1)
        link.Write((270, 0, *LASER_BLUE))
        time.sleep(1)

      new_flight = DifferentFlights(flight, last_flight)
      if new_flight:
        Log('Flight changed from %s to %s' % (
            messageboard.DisplayFlightNumber(last_flight),
            messageboard.DisplayFlightNumber(flight)
        ), ser=link)

        # Turn off laser so that line isn't traced while it moves to new position
        link.Write((*last_angles, *LASER_RGB_OFF))

      last_flight = flight




                            <----SKIPPED LINES---->




  - Display a histogram
  - Send information for a different display mode
  - Indicate that the battery is low

  Args:
    command: dictionary representing all data fields from remote.
    configuration: dictionary representing the current state of the messageboard
      configuration.
    display_mode: current display mode; only passed so that we may identify changes.
    low_battery: current battery status; only passed so that we may identify changes.
    to_parent_q: multiprocessing queue, where instructions to send back to messageboard,
      if any, can be placed.
    link: the open serial link.

  Returns:
    A 2-tuple of potentially-updated display_mode, and low_battery.
  """
  # command might update a setting; see if there's a change, and if so, write to disk
  setting_change = False
  log_lines = []

  setting_keys = ['setting_max_distance', 'setting_max_altitude',
                  'setting_on_time', 'setting_off_time', 'setting_delay']
  for key in setting_keys:
    if command.get(key) != configuration.get(key):
      log_lines.append(' |-->Setting %s updated from %s to %s' % (
          key, str(configuration.get(key)), str(command[key])))
      setting_change = True
      configuration[key] = command[key]
  remote_key = 'setting_screen_enabled_bool'
  system_key = 'setting_screen_enabled'
  # remote sees T/F whereas messageboard.py & the web interface expect 'on'/absent key
  if command[remote_key] and system_key not in configuration:
    setting_change = True
    configuration[system_key] = 'on'
    log_lines.append(' |-->Setting %s updated from None to on' % system_key)
  elif not command[remote_key] and system_key in configuration:
    setting_change = True
    configuration.pop(system_key)
    log_lines.append(' |-->Setting %s updated from on to None' % system_key)

  if setting_change:
    settings_string = messageboard.BuildSettings(configuration)
    to_parent_q.put(('update_configuration', (settings_string, )))

  # a command might request info about flight to be (re)displayed, irrespective of
  # whether the screen is on; if so, let's put that message at the front of the message
  # queue, and delete any subsequent messages in queue because presumably the button
  # was pushed either a) when the screen was off (so no messages in queue), or b)
  # because the screen was on, but the last flight details got lost after other screens!
  if command['last_plane']:
    to_parent_q.put(('replay', ()))
    log_lines.append(' |-->Requested last flight (re)display')

  # a command might request a histogram; simply generate and save a histogram file to disk
  if command['histogram_enabled']:
    h_type = GetName(HISTOGRAM_TYPES, command['current_hist_type'])
    h_history = GetName(HISTOGRAM_HISTORY, command['current_hist_history'])
    to_parent_q.put(('histogram', (h_type, h_history)))
    log_lines.append(' |-->Requested %s histogram with %s data' % (h_type, h_history))

  # a command might update us on the display mode; based on the display mode, we might
  # pass different attributes back to the remote




                            <----SKIPPED LINES---->




  last_configuration = configuration
  while not shutdown.value:
    if not to_arduino_q.empty():
      to_arduino_message = to_arduino_q.get(block=False)
      flight, json_desc_dict, configuration, additional_attr = to_arduino_message




      if 'setting_screen_enabled' not in last_configuration and 'setting_screen_enabled' in configuration:
        Log('setting_screen_enabled changed from NOT PRESENT to ON')
      if 'setting_screen_enabled' in last_configuration and 'setting_screen_enabled' not in configuration:
        Log('setting_screen_enabled changed from ON to NOT PRESENT')
      last_configuration = configuration




      if 'test_remote' in configuration:
        messageboard.RemoveSetting(configuration, 'test_remote')


        def TestDisplayMode(m):
          SendRemoteMessage(
              flight, json_desc_dict, configuration, additional_attr,
              m, write_keys, write_format_tuple, link)
          time.sleep(1)

        TestDisplayMode(DISP_LAST_FLIGHT_NUMB_ORIG_DEST)
        TestDisplayMode(DISP_LAST_FLIGHT_AZIMUTH_ELEVATION)
        TestDisplayMode(DISP_FLIGHT_COUNT_LAST_SEEN)
        TestDisplayMode(DISP_RADIO_RANGE)

    if time.time() >= next_write:
      next_write = SendRemoteMessage(
          flight, json_desc_dict, configuration, additional_attr,
          display_mode, write_keys, write_format_tuple, link)

    if time.time() >= next_read:
      bytes_read = []
      values_t = link.Read(bytes_read=bytes_read)




                            <----SKIPPED LINES---->

                            <----SKIPPED LINES---->




      *SERVO_CONNECTION, read_timeout=7,
      error_pin=messageboard.GPIO_ERROR_ARDUINO_SERVO_CONNECTION, to_parent_q=to_parent_q,
      read_format='l', write_format='ff???', name='Servo')
  link.Open()

  last_flight = {}
  last_angles = (0, 0)
  flight, json_desc_dict, configuration, additional_attr = InitialMessageValues(
      to_arduino_q)
  next_read = 0
  next_write = 0
  now = GetNow(json_desc_dict, additional_attr)

  while not shutdown.value:
    if not to_arduino_q.empty():
      flight, json_desc_dict, configuration, additional_attr = to_arduino_q.get(
          block=False)

      if 'test_servos' in configuration:
        messageboard.RemoveSetting(configuration, 'test_servos')
        configuration.pop('test_servos')  # ensure that this is triggered only once
        link.Write((0, 0, *LASER_RGB_OFF))
        time.sleep(1)
        link.Write((90, 0, *LASER_RED))
        time.sleep(1)
        link.Write((180, 0, *LASER_GREEN))
        time.sleep(1)
        link.Write((270, 0, *LASER_BLUE))
        time.sleep(1)

      new_flight = DifferentFlights(flight, last_flight)
      if new_flight:
        Log('Flight changed from %s to %s' % (
            messageboard.DisplayFlightNumber(last_flight),
            messageboard.DisplayFlightNumber(flight)
        ), ser=link)

        # Turn off laser so that line isn't traced while it moves to new position
        link.Write((*last_angles, *LASER_RGB_OFF))

      last_flight = flight




                            <----SKIPPED LINES---->




  - Display a histogram
  - Send information for a different display mode
  - Indicate that the battery is low

  Args:
    command: dictionary representing all data fields from remote.
    configuration: dictionary representing the current state of the messageboard
      configuration.
    display_mode: current display mode; only passed so that we may identify changes.
    low_battery: current battery status; only passed so that we may identify changes.
    to_parent_q: multiprocessing queue, where instructions to send back to messageboard,
      if any, can be placed.
    link: the open serial link.

  Returns:
    A 2-tuple of potentially-updated display_mode, and low_battery.
  """
  # command might update a setting; see if there's a change, and if so, write to disk
  setting_change = False
  log_lines = []
  new_configuration = {}
  setting_keys = ['setting_max_distance', 'setting_max_altitude',
                  'setting_on_time', 'setting_off_time', 'setting_delay']
  for key in setting_keys:
    if command.get(key) != configuration.get(key):
      log_lines.append(' |-->Setting %s updated from %s to %s' % (
          key, str(configuration.get(key)), str(command[key])))
      setting_change = True
    new_configuration[key] = command[key]
  remote_key = 'setting_screen_enabled_bool'
  system_key = 'setting_screen_enabled'
  # remote sees T/F whereas messageboard.py & the web interface expect 'on'/absent key
  if command[remote_key] and system_key not in configuration:
    setting_change = True
    new_configuration[system_key] = 'on'
    log_lines.append(' |-->Setting %s updated from None to on' % system_key)
  elif not command[remote_key] and system_key in configuration:
    setting_change = True

    log_lines.append(' |-->Setting %s updated from on to None' % system_key)

  if setting_change:
    settings_string = messageboard.BuildSettings(new_configuration)
    to_parent_q.put(('update_configuration', (settings_string, )))

  # a command might request info about flight to be (re)displayed, irrespective of
  # whether the screen is on; if so, let's put that message at the front of the message
  # queue, and delete any subsequent messages in queue because presumably the button
  # was pushed either a) when the screen was off (so no messages in queue), or b)
  # because the screen was on, but the last flight details got lost after other screens!
  if command['last_plane']:
    to_parent_q.put(('replay', ()))
    log_lines.append(' |-->Requested last flight (re)display')

  # a command might request a histogram; simply generate and save a histogram file to disk
  if command['histogram_enabled']:
    h_type = GetName(HISTOGRAM_TYPES, command['current_hist_type'])
    h_history = GetName(HISTOGRAM_HISTORY, command['current_hist_history'])
    to_parent_q.put(('histogram', (h_type, h_history)))
    log_lines.append(' |-->Requested %s histogram with %s data' % (h_type, h_history))

  # a command might update us on the display mode; based on the display mode, we might
  # pass different attributes back to the remote




                            <----SKIPPED LINES---->




  last_configuration = configuration
  while not shutdown.value:
    if not to_arduino_q.empty():
      to_arduino_message = to_arduino_q.get(block=False)
      flight, json_desc_dict, configuration, additional_attr = to_arduino_message




      if 'setting_screen_enabled' not in last_configuration and 'setting_screen_enabled' in configuration:
        Log('setting_screen_enabled changed from NOT PRESENT to ON')
      if 'setting_screen_enabled' in last_configuration and 'setting_screen_enabled' not in configuration:
        Log('setting_screen_enabled changed from ON to NOT PRESENT')
      last_configuration = configuration




      if 'test_remote' in configuration:
        messageboard.RemoveSetting(configuration, 'test_remote')
        configuration.pop('test_remote')  # ensure that this is triggered only once

        def TestDisplayMode(m):
          SendRemoteMessage(
              flight, json_desc_dict, configuration, additional_attr,
              m, write_keys, write_format_tuple, link)
          time.sleep(1)

        TestDisplayMode(DISP_LAST_FLIGHT_NUMB_ORIG_DEST)
        TestDisplayMode(DISP_LAST_FLIGHT_AZIMUTH_ELEVATION)
        TestDisplayMode(DISP_FLIGHT_COUNT_LAST_SEEN)
        TestDisplayMode(DISP_RADIO_RANGE)

    if time.time() >= next_write:
      next_write = SendRemoteMessage(
          flight, json_desc_dict, configuration, additional_attr,
          display_mode, write_keys, write_format_tuple, link)

    if time.time() >= next_read:
      bytes_read = []
      values_t = link.Read(bytes_read=bytes_read)




                            <----SKIPPED LINES---->