#!/usr/bin/env python3 # -*- coding: utf-8 -*- """ Created on Sun Dec 27 20:43:40 2020 @author: DJ2LS """ import logging import threading import time import static import modem import helpers from random import randrange modem = modem.RF() #crc_algorithm = crcengine.new('crc16-ccitt-false') #load crc16 library static.ARQ_PAYLOAD_PER_FRAME = static.FREEDV_PAYLOAD_PER_FRAME - 3 #6?! static.ARQ_ACK_PAYLOAD_PER_FRAME = 14 - 2# --> 700D def arq_ack_timeout(): static.ACK_TIMEOUT = 1 def data_received(data_in): ARQ_N_RX_BURSTS = int.from_bytes(bytes(data_in[:1]), "big") - 10 static.ARQ_RX_BURST_BUFFER.append(data_in) #append data to RX BUFFER print("WAITING FOR BURSTS: " + str(ARQ_N_RX_BURSTS)) print("ARQ_RX_BURST_BUFFER: " + str(len(static.ARQ_RX_BURST_BUFFER))) burst_total_payload = bytearray() #while static.ACK_RX_TIMEOUT == 0: #define timeout where data has to be received untl error occurs if len(static.ARQ_RX_BURST_BUFFER) == ARQ_N_RX_BURSTS: #if received bursts are equal to burst number in frame #burst_total_payload = bytearray() for n_raw_frame in range(0,len(static.ARQ_RX_BURST_BUFFER)): burst_frame = static.ARQ_RX_BURST_BUFFER[n_raw_frame] #get burst frame burst_payload = burst_frame[3:] #remove frame type and burst CRC burst_total_payload = burst_total_payload + burst_payload #stick bursts together # ------------------ caculate CRC of BURST #print(burst_total_payload) # helpers.get_crc_16(data) burst_payload_crc = helpers.get_crc_16(burst_total_payload) #burst_payload_crc = crc_algorithm(burst_total_payload) #burst_payload_crc = burst_payload_crc.to_bytes(2, byteorder='big') #print(burst_payload_crc) # IF BURST CRC IS CORRECT, APPEND BURST TO BUFFER AND SEND ACK FRAME if burst_payload_crc == data_in[1:3]: ##### WAIT SOME TIME TO PREVENT TIMING ISSUES --> NEEDS TO BE OPTIMIZED LATER #####time.sleep(2) logging.info("BURST CRC ARE EQUAL!") #print(burst_total_payload) static.ARQ_RX_FRAME_BUFFER.append(burst_total_payload) # IF CRC TRUE APPEND burst_total_payload TO ARQ_RX_FRAME_BUFFER #print(data_in[7:9]) #BUILDING ACK FRAME ----------------------------------------------- ack_payload = bytes(burst_payload_crc) #ack_frame = b'\7'+ bytes(burst_payload_crc) #ack_preamble = b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00' ack_frame = b'<'+ bytes(burst_payload_crc) # < = 60 #ack_frame[1] = b'\7' #ack_frame[2] = helpers.get_crc8(data) #ack_frame[3:4] = bytes(burst_payload_crc) frametype = int.from_bytes(bytes(ack_frame[:1]), "big") print("ACK TYPE: " + str(frametype)) ack_buffer = bytearray(static.ARQ_ACK_PAYLOAD_PER_FRAME) ack_buffer[:len(ack_frame)] = ack_frame # set buffersize to length of data which will be send #TRANSMIT ACK FRAME ----------------------------------------------- logging.info("TX | SENDING ARQ BURST ACK [" + str(data_in[1:3]) +"]") modem.transmit(7,ack_buffer) print(ack_buffer) # ------------------------------------------------------------ frametype = int.from_bytes(bytes(ack_buffer[:1]), "big") print("ACK TYPE: " + str(frametype)) # ---------------------------------------------------------------- static.ARQ_RX_BURST_BUFFER = [] # CLEAR RX BURST BUFFER else: #IF burst payload crc and input crc are NOT equal print("CRC NOT EQUAL!!!!!") print(data_in[1:3]) static.ARQ_RX_BURST_BUFFER = [] # LOOP THOUGH FRAME BUFFER AND STICK EVERYTHING TOGETHER # WE ALSO CHECK FOR FRAME HEADER AND LAST FRAME complete_frame = bytearray() print(static.ARQ_RX_FRAME_BUFFER) for frame in range(len(static.ARQ_RX_FRAME_BUFFER)): complete_frame = complete_frame + static.ARQ_RX_FRAME_BUFFER[frame] print(complete_frame) print(complete_frame[4:6]) # -------- DETECT IF WE ALREADY RECEIVED A FRAME HEADER THEN SAVE DATA TO GLOBALS #if burst_total_payload[4:6].startswith(b'\xAA\xAA'): if complete_frame[4:6].startswith(b'\xAA\xAA') or burst_total_payload[4:6].startswith(b'\xAA\xAA'): print("FRAME HEADER RECEIVED!") #print("FRAME BURSTS = " + str(complete_frame[:2])) #print("FRAME CRC = " + str(complete_frame[2:4])) static.FRAME_CRC = complete_frame[2:4] static.ARQ_RX_FRAME_N_BURSTS = int.from_bytes(bytes(complete_frame[:2]), "big") # -------- DETECT IF WE HAVE ALREADY RECEIVED THE LAST FRAME if burst_total_payload.rstrip(b'\x00').endswith(b'\xFF\xFF'): print("DAS IST DER LETZTE BURST MIT EOF!!!") print("WEITER GEHTS") # NOW WE TRY TO SEPARATE THE FRAME CRC FOR A CRC CALCULATION frame_payload = complete_frame.rstrip(b'\x00') #REMOVE x00 frame_payload = frame_payload[6:-2] #THIS IS THE FRAME PAYLOAD frame_payload_crc = helpers.get_crc_16(frame_payload) #frame_payload_crc = crc_algorithm(frame_payload) #frame_payload_crc = frame_payload_crc.to_bytes(2, byteorder='big') #IF THE FRAME PAYLOAD CRC IS EQUAL TO THE FRAME CRC WHICH IS KNOWN FROM THE HEADER --> SUCCESS if frame_payload_crc == static.FRAME_CRC: logging.info("RX | FILE SUCESSFULL RECEIVED! - TIME TO PARTY") static.RX_BUFFER.append(frame_payload) static.ARQ_RX_FRAME_BUFFER = [] #print(static.RX_BUFFER[-1]) # HERE: SEND ACK FOR TOTAL FRAME!!! #else: #print("CRC FOR FRAME NOT EQUAL!") # print("FRAME PAYLOAD CRC: " + str(frame_payload_crc)) # print("FRAME PAYLOAD: " + str(frame_payload)) #print("COMPLETE FRAME: " + str(complete_frame)) #static.ARQ_RX_FRAME_BUFFER = [] # ---> BUFFER ERST LÖSCHEN WENN MINDESTANZAHL AN BURSTS ERHALTEN WORDEN SIND def ack_received(): logging.info("RX | ACK RCVD!") static.ACK_TIMEOUT = 1 #Force timer to stop waiting static.ACK_RECEIVED = 1 #Force data loops of TNC to stop and continue with next frame # static.ARQ_ACK_WAITING_FOR_ID def transmit(data_out): #static.ARQ_PAYLOAD_PER_FRAME = static.FREEDV_PAYLOAD_PER_FRAME - 3 #----------------------- BUILD A FRAME WITH CRC AND N BURSTS SO THE RECEIVER GETS THIS INFORMATION frame_BOF = b'\xAA\xAA' frame_EOF = b'\xFF\xFF' frame_header_length = 8 n_bursts_prediction = (len(data_out)+frame_header_length) // static.ARQ_PAYLOAD_PER_FRAME + ((len(data_out)+frame_header_length) % static.ARQ_PAYLOAD_PER_FRAME > 0) # aufrunden 3.2 = 4 n_bursts_prediction = n_bursts_prediction.to_bytes(2, byteorder='big') #65535 frame_payload_crc = helpers.get_crc_16(data_out) #frame_payload_crc = crc_algorithm(data_out) #frame_payload_crc = frame_payload_crc.to_bytes(2, byteorder='big') # This is the total frame with frame header, which will be send data_out = n_bursts_prediction + frame_payload_crc + frame_BOF + data_out + frame_EOF # 2 2 2 N 2 #print(data_out) # --------------------------------------------- LETS CREATE A BUFFER BY SPLITTING THE FILES INTO PEACES static.TX_BUFFER = [data_out[i:i+static.ARQ_PAYLOAD_PER_FRAME] for i in range(0, len(data_out), static.ARQ_PAYLOAD_PER_FRAME)] static.TX_BUFFER_SIZE = len(static.TX_BUFFER) logging.info("TX | TOTAL PAYLOAD BYTES/FRAMES TO SEND: " + str(len(data_out)) + " / " + str(static.TX_BUFFER_SIZE)) ###static.ACK_RECEIVED = 0 # SET ACK RECEIVED TO 0 IF NOT ALREADY DONE TO BE SURE WE HAVE A NEW CYCLE # --------------------------------------------- THIS IS THE MAIN LOOP static.ARQ_N_SENT_FRAMES = 0 # SET N SENT FRAMES TO 0 FOR A NEW SENDING CYCLE while static.ARQ_N_SENT_FRAMES <= static.TX_BUFFER_SIZE: print("static.ARQ_N_SENT_FRAMES: " + str(static.ARQ_N_SENT_FRAMES)) ############################----------RANDOM FRAMES PER BURST MACHINE --> HELPER FOR SIMULATING DYNAMIC ARQ UNTIL BURST MACHINE IS BUILD #static.ARQ_TX_N_FRAMES = get_n_frames_per_burst(len(data_out)) static.ARQ_TX_N_FRAMES = get_n_frames_per_burst() static.ACK_RECEIVED = 0 # SET ACK RECEIVED TO 0 IF NOT ALREADY DONE TO BE SURE WE HAVE A NEW CYCLE ################################################################# # ----------- SET FRAME PAYLOAD TO BE ABLE TO CREATE CRC burst_total_payload = bytearray() try: # DETECT IF LAST BURST TO PREVENT INDEX ERROR OF BUFFER for i in range(static.ARQ_TX_N_FRAMES): #bytearray(b'111111111111111111111111222222222222222222222222') # we need to make sure, payload data is always as long as static.ARQ_PAYLOAD_PER_FRAME beacuse of CRC! burst_raw_payload = static.TX_BUFFER[static.ARQ_N_SENT_FRAMES + i] burst_payload = bytearray(static.ARQ_PAYLOAD_PER_FRAME) burst_payload[:len(burst_raw_payload)] = burst_raw_payload # set buffersize to length of data which will be send burst_total_payload = burst_total_payload + burst_payload except IndexError: # IF LAST BURST DETECTED BUILD CRC WITH LESS FRAMES AND SET static.ARQ_TX_N_FRAMES TO VALUE OF REST! burst_total_payload = bytearray() # reset burst_total_payload because of possible input remaining of detecting loop one step above if static.ARQ_N_SENT_FRAMES == 0 and (static.ARQ_TX_N_FRAMES > static.TX_BUFFER_SIZE): #WE CANT DO MODULO 0 --> CHECK IF FIRST FRAME == LAST FRAME static.ARQ_TX_N_FRAMES = static.TX_BUFFER_SIZE elif static.ARQ_N_SENT_FRAMES == 1 and (static.ARQ_TX_N_FRAMES > static.TX_BUFFER_SIZE): # MODULO 1 WILL ALWAYS BE 0 --> THIS FIXES IT static.ARQ_TX_N_FRAMES = static.TX_BUFFER_SIZE - static.ARQ_N_SENT_FRAMES else: static.ARQ_TX_N_FRAMES = (static.TX_BUFFER_SIZE % static.ARQ_N_SENT_FRAMES) #print("static.TX_BUFFER_SIZE: " + str(static.TX_BUFFER_SIZE)) #print("static.ARQ_N_SENT_FRAMES: " + str(static.ARQ_N_SENT_FRAMES)) print("ARQ_TX_N_FRAMES OF LAST BURST: " + str(static.ARQ_TX_N_FRAMES)) for i in range(static.ARQ_TX_N_FRAMES): #bytearray(b'111111111111111111111111222222222222222222222222') # we need to make sure, payload data is always as long as static.ARQ_PAYLOAD_PER_FRAME beacuse of CRC! burst_raw_payload = static.TX_BUFFER[static.ARQ_N_SENT_FRAMES + i] burst_payload = bytearray(static.ARQ_PAYLOAD_PER_FRAME) burst_payload[:len(burst_raw_payload)] = burst_raw_payload # set buffersize to length of data which will be send burst_total_payload = burst_total_payload + burst_payload # ----------- GENERATE PAYLOAD CRC FOR ARQ_TX_N_FRAMES burst_payload_crc = helpers.get_crc_16(burst_total_payload) #burst_payload_crc = crc_algorithm(burst_total_payload) #burst_payload_crc = burst_payload_crc.to_bytes(2, byteorder='big') static.ARQ_ACK_WAITING_FOR_ID = burst_payload_crc #set the global variable so we know for which ACK we are waiting for #------------------ BUILD ARQBURSTS--------------------------------------------- arqburst = [] for i in range(static.ARQ_TX_N_FRAMES): frame_type = 10 + static.ARQ_TX_N_FRAMES frame_type = bytes([frame_type]) payload_data = bytes(static.TX_BUFFER[static.ARQ_N_SENT_FRAMES + i]) arqframe = frame_type + burst_payload_crc + payload_data buffer = bytearray(static.FREEDV_PAYLOAD_PER_FRAME) # create TX buffer buffer[:len(arqframe)] = arqframe # set buffersize to length of data which will be send arqburst.append(buffer) #append data to a buffer array, so we can loop through it #--------------------------------------------- N ATTEMPTS TO SEND BURSTS IF ACK RECEPTION FAILS for static.TX_N_RETRIES in range(static.TX_N_MAX_RETRIES): static.ACK_RECEIVED = 0 #SET AGAIN ACK_RECEIVED TO 0 SO WE CAN BE SURE WE ARE WAITING FOR THE CORRECT ACK # ----------------------- Loop through ARQ FRAMES BUFFER with N = Numbers of frames which will be send at once for n in range(static.ARQ_TX_N_FRAMES): logging.info("TX | SENDING BURST [" + str(n+1) + " / " + str(static.ARQ_TX_N_FRAMES) + "] [" + str(static.ARQ_N_SENT_FRAMES + n+1) + " / " + str(static.TX_BUFFER_SIZE) + "] [" + str(burst_payload_crc) + "]") modem.transmit(12, arqburst[n]) #LETS SLEEP SOME TIME FOR TX COOLDOWN --> CAN BE REMOVED LATER IF SYNC/UNSYNC OF FREEDV IS WORKING BETTER #########################time.sleep(4) # --------------------------- START TIMER FOR WAITING FOR ACK ---> IF TIMEOUT REACHED, ACK_TIMEOUT = 1 static.ACK_TIMEOUT = 0 timer = threading.Timer(static.ACK_TIMEOUT_SECONDS * static.ARQ_TX_N_FRAMES, arq_ack_timeout) timer.start() logging.info("TX | WAITING FOR ACK") #static.MODEM_RECEIVE = False # --------------------------- WHILE TIMEOUT NOT REACHED AND NO ACK RECEIVED --> LISTEN while static.ACK_TIMEOUT == 0 and static.ACK_RECEIVED == 0: time.sleep(0.05) # here we reduce CPU load #static.MODEM_RECEIVE = True #else: #logging.info("TX | ACK TIMEOUT - SENDING AGAIN") #pass #static.MODEM_RECEIVE = False #time.sleep(1) #--------------- BREAK LOOP IF ACK HAS BEEN RECEIVED ######if static.ACK_RECEIVED == 1: if static.ACK_RECEIVED == 1: #static.MODEM_RECEIVE = False #time.sleep(1) #-----------IF ACK RECEIVED, INCREMENT ITERATOR FOR MAIN LOOP TO PROCEED WITH NEXT FRAMES/BURST static.ARQ_N_SENT_FRAMES = static.ARQ_N_SENT_FRAMES + static.ARQ_TX_N_FRAMES break # ----------- if no ACK received and out of retries.....stop frame sending if static.ACK_RECEIVED == 0: logging.info("TX | NO ACK RECEIVED | FRAME NEEDS TO BE RESEND!") break #-------------------------BREAK TX BUFFER LOOP IF ALL PACKETS HAVE BEEN SENT if static.ARQ_N_SENT_FRAMES == static.TX_BUFFER_SIZE: break # ------------ TIMER TO WAIT UNTIL NEXT PACKAGE WILL BE SEND TO PREVENT TIME ISSEUS --> NEEDS TO BE IMPROVED LATER time.sleep(5) # IF TX BUFFER IS EMPTY / ALL FRAMES HAVE BEEN SENT --> HERE WE COULD ADD AN static.VAR for IDLE STATE logging.info("TX | BUFFER EMPTY") # BURST MACHINE TO DEFINE N BURSTS PER FRAME ---> LATER WE CAN USE CHANNEL MESSUREMENT TO SET FRAMES PER BURST def get_n_frames_per_burst(): n_frames_per_burst = randrange(1,5) return n_frames_per_burst