# along with this program. If not, see <http://www.gnu.org/licenses/>.
-# This hack allows MorseTranslator to be imported also when
+# This hack allows importing local modules also when
# __name__ == "__main__"
try:
+ from .MorseDistanceModulator import MorseDistanceModulator
from .MorseTranslator import MorseTranslator
except SystemError:
+ from MorseDistanceModulator import MorseDistanceModulator
from MorseTranslator import MorseTranslator
import logging
import time
-class SymbolTime(object):
- """
- In theory the symbol distance (the distance to discriminate symbols) can
- be arbitrary, and it's only bounded below by the stability of the pulse
- time, but in practice it can be necessary to wait a predefined minimum
- amount of time between pulses because of technological limits of the
- transmitting devices, we call this time the "minimum inter-symbol
- distance".
- """
-
- # pylint: disable=too-few-public-methods
- def __init__(self, pulse_min, pulse_max, multiplier,
- min_inter_symbol_distance=0.0):
- assert multiplier >= 0
- if (pulse_min == pulse_max) and (min_inter_symbol_distance == 0):
- raise ValueError("If (pulse_min == pulse_max) a non-zero",
- "inter-symbol distance MUST be specified")
-
- symbol_distance = 2 * (pulse_max - pulse_min)
- if symbol_distance == 0:
- symbol_distance = min_inter_symbol_distance
-
- # The time the transmitter has to wait to disambiguate between this
- # symbol and a different one.
- self.dist = min_inter_symbol_distance + symbol_distance * multiplier
-
- # The minimum time which represents the symbol at the receiving end.
- self.min = min_inter_symbol_distance + pulse_min + \
- symbol_distance * multiplier
-
- # The maximum time which represents the symbol at the receiving end
- self.max = min_inter_symbol_distance + pulse_min + \
- symbol_distance * (multiplier + 1)
+def log_symbol(distance, symbol, extra_info=""):
+ logging.info("distance: %.2f Received \"%s\"%s", distance, symbol,
+ extra_info)
class CallDistanceTransceiver(object):
"""
def __init__(self, modem,
- call_setup_time_min=7, call_setup_time_max=15,
+ call_setup_time_min=7, call_setup_time_max=16.5,
ring_time_min=4.8, ring_time_max=5.2,
add_inter_call_distance=True):
"""Encode the Morse symbols using the distance between calls.
self.modem = modem
self.translator = MorseTranslator()
- self.destination_number = ""
-
- self.call_setup_time_min = call_setup_time_min
self.call_setup_time_max = call_setup_time_max
- self.ring_time_min = ring_time_min
- self.ring_time_max = ring_time_max
-
if add_inter_call_distance:
# Analog modems don't like to dial a new call immediately after
# they hung up the previous one; an extra delay of about one
else:
inter_symbol_distance = 0
- self.dot_time = SymbolTime(call_setup_time_min,
- call_setup_time_max, 0,
- inter_symbol_distance)
- self.dash_time = SymbolTime(call_setup_time_min,
- call_setup_time_max, 1,
- inter_symbol_distance)
- self.signalspace_time = SymbolTime(call_setup_time_min,
- call_setup_time_max, 2,
- inter_symbol_distance)
- self.wordspace_time = SymbolTime(call_setup_time_min,
- call_setup_time_max, 3,
- inter_symbol_distance)
- self.eom_time = SymbolTime(call_setup_time_min,
- call_setup_time_max, 4,
- inter_symbol_distance)
+ self.modulator = MorseDistanceModulator(call_setup_time_min,
+ call_setup_time_max,
+ ring_time_min,
+ ring_time_max,
+ inter_symbol_distance)
logging.debug("call setup time between %.2f and %.2f "
"--------- dot transmit time: %.2f + %.2f "
"receive time: between %.2f and %.2f",
- self.call_setup_time_min,
- self.call_setup_time_max,
- self.call_setup_time_max,
- self.dot_time.dist,
- self.dot_time.min,
- self.dot_time.max)
+ self.modulator.period_min,
+ self.modulator.period_max,
+ self.modulator.period_max,
+ self.modulator.dot_time.dist,
+ self.modulator.dot_time.min,
+ self.modulator.dot_time.max)
logging.debug("call setup time between %.2f and %.2f "
"-------- dash transmit time: %.2f + %.2f "
"receive time: between %.2f and %.2f",
- self.call_setup_time_min,
- self.call_setup_time_max,
- self.call_setup_time_max,
- self.dash_time.dist,
- self.dash_time.min,
- self.dash_time.max)
+ self.modulator.period_min,
+ self.modulator.period_max,
+ self.modulator.period_max,
+ self.modulator.dash_time.dist,
+ self.modulator.dash_time.min,
+ self.modulator.dash_time.max)
logging.debug("call setup time between %.2f and %.2f "
"- signalspace transmit time: %.2f + %.2f "
"receive time: between %.2f and %.2f",
- self.call_setup_time_min,
- self.call_setup_time_max,
- self.call_setup_time_max,
- self.signalspace_time.dist,
- self.signalspace_time.min,
- self.signalspace_time.max)
+ self.modulator.period_min,
+ self.modulator.period_max,
+ self.modulator.period_max,
+ self.modulator.signalspace_time.dist,
+ self.modulator.signalspace_time.min,
+ self.modulator.signalspace_time.max)
logging.debug("call setup time between %.2f and %.2f "
"--- wordspace transmit time: %.2f + %.2f "
"receive time: between %.2f and %.2f",
- self.call_setup_time_min,
- self.call_setup_time_max,
- self.call_setup_time_max,
- self.wordspace_time.dist,
- self.wordspace_time.min,
- self.wordspace_time.max)
+ self.modulator.period_min,
+ self.modulator.period_max,
+ self.modulator.period_max,
+ self.modulator.wordspace_time.dist,
+ self.modulator.wordspace_time.min,
+ self.modulator.wordspace_time.max)
logging.debug("call setup time between %.2f and %.2f "
"--------- EOM transmit time: %.2f + %.2f "
"receive time: between %.2f and inf",
- self.call_setup_time_min,
- self.call_setup_time_max,
- self.call_setup_time_max,
- self.eom_time.dist,
- self.eom_time.min)
+ self.modulator.period_min,
+ self.modulator.period_max,
+ self.modulator.period_max,
+ self.modulator.eom_time.dist,
+ self.modulator.eom_time.min)
self.previous_ring_time = -1
self.previous_call_time = -1
self.end_of_message = False
- def log_symbol(self, distance, symbol, extra_info=""):
- logging.info("distance: %.2f Received \"%s\"%s", distance, symbol,
- extra_info)
-
- def receive_character(self):
+ def receive_symbol(self):
current_ring_time = time.time()
if self.previous_ring_time == -1:
self.previous_ring_time = current_ring_time
self.previous_call_time = current_ring_time
- self.log_symbol(0, "", "(The very first ring)")
+ log_symbol(0, "", "(The very first ring)")
return
ring_distance = current_ring_time - self.previous_ring_time
self.previous_ring_time = current_ring_time
# Ignore multiple rings in the same call
- if ring_distance > self.ring_time_min and \
- ring_distance <= self.ring_time_max:
+ if self.modulator.is_same_period(ring_distance):
logging.debug("multiple rings in the same call, distance: %.2f",
ring_distance)
return
call_distance = current_ring_time - self.previous_call_time
self.previous_call_time = current_ring_time
- if call_distance > self.dot_time.min and \
- call_distance <= self.dot_time.max:
- self.log_symbol(call_distance, '.')
- self.morse_message += "."
- return
-
- if call_distance > self.dash_time.min and \
- call_distance <= self.dash_time.max:
- self.log_symbol(call_distance, '-')
- self.morse_message += "-"
+ try:
+ symbol = self.modulator.distance_to_symbol(call_distance)
+ except ValueError as err:
+ logging.error("%s", err)
+ logging.error("Check the transmitter and receiver parameters")
return
- if call_distance > self.signalspace_time.min and \
- call_distance <= self.signalspace_time.max:
+ extra_info = ""
+ if symbol in [" ", "/", "EOM"]:
signal = self.morse_message.strip().split(' ')[-1]
character = self.translator.signal_to_character(signal)
- self.log_symbol(call_distance, ' ', " got \"%s\"" % character)
- self.morse_message += " "
- return
+ extra_info = " got \"%s\"" % character
- if call_distance > self.wordspace_time.min and \
- call_distance <= self.wordspace_time.max:
- signal = self.morse_message.strip().split(' ')[-1]
- character = self.translator.signal_to_character(signal)
- self.log_symbol(call_distance, '/', " got \"%s\"" % character)
- self.morse_message += " / "
- return
+ log_symbol(call_distance, symbol, extra_info)
- if call_distance > self.eom_time.min:
- signal = self.morse_message.strip().split(' ')[-1]
- character = self.translator.signal_to_character(signal)
- self.log_symbol(call_distance, 'EOM', " got \"%s\"" % character)
+ if symbol != "EOM":
+ # Add spaces around the wordspace symbol to make it easier to split
+ # the Morse message in symbols later on
+ if symbol == "/":
+ symbol = " / "
+ self.morse_message += symbol
+ else:
self.end_of_message = True
self.previous_ring_time = -1
self.previous_call_time = -1
- return
-
- # if the code made it up to here, something fishy is going on
- logging.error("Unexpected distance: %.2f", call_distance)
- logging.error("Check the transmitter and receiver parameters")
def receive_loop(self):
while not self.end_of_message:
self.modem.get_response("RING")
- self.receive_character()
+ self.receive_symbol()
logging.debug("Current message: %s", self.morse_message)
self.end_of_message = False
def get_text(self):
return self.text_message
- def transmit_symbol(self, symbol):
- if symbol == ".":
- sleep_time = self.dot_time.dist
- elif symbol == "-":
- sleep_time = self.dash_time.dist
- elif symbol == " ":
- sleep_time = self.signalspace_time.dist
- elif symbol == "/":
- sleep_time = self.wordspace_time.dist
- elif symbol == "EOM":
- sleep_time = self.eom_time.dist
- elif symbol is None:
- # To terminate the transmission just call and hangup, with no extra
- # distance
- sleep_time = 0
-
+ def transmit_symbol(self, destination_number, symbol, sleep_time):
logging.info("Dial and wait %.2f = %.2f + %.2f seconds "
"(transmitting '%s')",
self.call_setup_time_max + sleep_time,
# Dial, then wait self.call_setup_time_max to make sure the receiver
# gets at least one RING, and then hangup and sleep the time needed to
# transmit a symbol.
- self.modem.send_command("ATDT" + self.destination_number + ";")
+ time_before = time.time()
+ self.modem.send_command("ATDT" + destination_number + ";")
time.sleep(self.call_setup_time_max)
self.modem.send_command("ATH")
self.modem.get_response()
- time.sleep(sleep_time)
+ time_after = time.time()
- def transmit_signal(self, signal):
- logging.debug("Transmitting signal: %s", signal)
- for symbol in signal:
- self.transmit_symbol(symbol)
+ # Account for possible delays in order to be as adherent as
+ # possible to the nominal total symbol transmission distance.
+ delay = (time_after - time_before) - self.call_setup_time_max
+ logging.debug("Delay %.2f", delay)
- def transmit(self, message, destination_number):
- self.destination_number = destination_number
+ remaining_sleep_time = sleep_time - delay
+ if remaining_sleep_time < 0:
+ remaining_sleep_time = 0
+ logging.debug("Should sleep %.2f. Will sleep %.2f", sleep_time,
+ remaining_sleep_time)
+ time.sleep(remaining_sleep_time)
+
+ def transmit(self, message, destination_number):
morse_message = self.translator.text_to_morse(message)
- signals = morse_message.split()
+ distances = self.modulator.modulate(morse_message)
logging.debug("Starting the transmission")
- for i, signal in enumerate(signals):
- logging.debug("Transmitting '%s' as '%s'", message[i], signal)
- self.transmit_signal(signal)
-
- # Transmit a signal separator only when strictly necessary:
- # - after the last symbol, we are going to transmit an EOM
- # anyway, and that will mark the end of the last symbol.
- # - between words the word separator act as a symbol separator
- # too.
- if i != len(signals) - 1 and signals[i + 1] != "/" and signal != "/":
- self.transmit_symbol(" ")
-
- self.transmit_symbol("EOM")
+ for i, distance in enumerate(distances):
+ # Use 'None' for the last call
+ if i == len(distances) - 1:
+ symbol = None
+ else:
+ total_sleep_time = self.call_setup_time_max + distance
+ symbol = self.modulator.distance_to_symbol(total_sleep_time)
- # Since the Morse signals are encoded in the distance between calls, an
- # extra call is needed in order for receiver actually get the EOM and
- # see that the transmission has terminated.
- self.transmit_symbol(None)
+ self.transmit_symbol(destination_number, symbol, distance)
def estimate_transmit_duration(self, message):
morsemessage = self.translator.text_to_morse(message)
- signals = morsemessage.split()
+ logging.debug(morsemessage)
- logging.debug(signals)
+ distances = self.modulator.modulate(morsemessage)
transmitting_time = 0
- for i, signal in enumerate(signals):
- logging.debug("signal: %s", signal)
-
- for symbol in signal:
- transmitting_time += self.call_setup_time_max
- if symbol == ".":
- transmitting_time += self.dot_time.dist
- elif symbol == "-":
- transmitting_time += self.dash_time.dist
- elif symbol == "/":
- transmitting_time += self.wordspace_time.dist
-
- if i != len(signals) - 1 and signals[i + 1] != "/" and symbol != "/":
- transmitting_time += self.call_setup_time_max
- transmitting_time += self.signalspace_time.dist
-
- transmitting_time += self.call_setup_time_max
- transmitting_time += self.eom_time.dist
-
- # The final call needed for the receiver to get the EOM
- transmitting_time += self.call_setup_time_max
+ for distance in distances:
+ transmitting_time += self.call_setup_time_max
+ transmitting_time += distance
logging.debug("Estimated transmitting time: %.2f seconds",
transmitting_time)
-def test_send_receive():
+def test_transmit_receive():
logging.basicConfig(level=logging.DEBUG)
call_setup_time_min = 0
call_setup_time_max = 0.01
def send_command(self, command):
pass
- def get_response(self, response):
+ def get_response(self, response=None):
# pylint: disable=unused-argument
- setup_time = random.uniform(self.transceiver.call_setup_time_min,
- self.transceiver.call_setup_time_max)
+ setup_time = random.uniform(self.transceiver.modulator.period_min,
+ self.transceiver.modulator.period_max)
if self.ring_count == 0:
# dummy ring
pass
elif self.ring_count == 1:
# received a '.'
- time.sleep(setup_time + self.transceiver.dot_time.dist)
+ dot_time = self.transceiver.modulator.dot_time.dist
+ time.sleep(setup_time + dot_time)
elif self.ring_count == 2:
# received a '/'
- time.sleep(setup_time + self.transceiver.wordspace_time.dist)
+ wordspace_time = self.transceiver.modulator.wordspace_time.dist
+ time.sleep(setup_time + wordspace_time)
else:
# received an 'EOM'
- time.sleep(setup_time + self.transceiver.eom_time.dist)
+ eom_time = self.transceiver.modulator.eom_time.dist
+ time.sleep(setup_time + eom_time)
self.ring_count += 1
self.ring_count %= 4
modem.transceiver = xcv
+ xcv.transmit("CODEX PARIS", "0")
+
while True:
- xcv.receive_loop()
modem.ring_count = 0
+ xcv.receive_loop()
print()
print("Message received!")
print("\"%s\"" % xcv.get_text(), flush=True)
if __name__ == "__main__":
- test_send_receive()
+ test_transmit_receive()
projects / SaveMySugar / python3-savemysugar.git / blobdiff