#!/usr/bin/env python3 # -*- coding: utf-8 -*- """ Created on Sun Dec 27 20:43:40 2020 @author: DJ2LS """ import logging import threading import time from random import randrange import static import modem import helpers modem = modem.RF() static.ARQ_PAYLOAD_PER_FRAME = static.FREEDV_DATA_PAYLOAD_PER_FRAME - 3 #6?! static.ARQ_ACK_PAYLOAD_PER_FRAME = 14 - 2# def arq_ack_timeout(): static.ARQ_ACK_TIMEOUT = 1 def data_received(data_in): static.ARQ_N_FRAME = int.from_bytes(bytes(data_in[:1]), "big") - 10 #get number of frame static.ARQ_N_RX_FRAMES_PER_BURSTS = int.from_bytes(bytes(data_in[1:2]), "big") #get number of bursts from received frame logging.info("ARQ | RX | FRAME [" + str(static.ARQ_N_FRAME) + "/" + str(static.ARQ_N_RX_FRAMES_PER_BURSTS) + "] [" + str((static.ARQ_N_FRAME / static.ARQ_N_RX_FRAMES_PER_BURSTS)*100) + "%]") #allocate ARQ_RX_BURST_BUFFER as a list with "None" if not already done. This should be done only once per burst! # here we will save the N frame of a burst to N list position so we can explicit search for it if static.ARQ_N_RX_FRAMES_PER_BURSTS != len(static.ARQ_RX_BURST_BUFFER) and static.ARQ_N_FRAME == 1: for i in range(0,static.ARQ_N_RX_FRAMES_PER_BURSTS+1): static.ARQ_RX_BURST_BUFFER.insert(i,None) #print(len(static.ARQ_RX_BURST_BUFFER)) # now we add the incoming data to the specified position in our list static.ARQ_RX_BURST_BUFFER[static.ARQ_N_FRAME] = bytes(data_in) # run only if we recieved all ARQ FRAMES per ARQ BURST burst_total_payload = bytearray() if static.ARQ_N_FRAME == static.ARQ_N_RX_FRAMES_PER_BURSTS: #if received bursts are equal to burst number in frame print("len ARQ_RX_BURST_BUFFER: " + str(len(static.ARQ_RX_BURST_BUFFER)-1)) print("static.ARQ_N_FRAME: " + str(static.ARQ_N_FRAME)) print("static.ARQ_N_RX_FRAMES_PER_BURSTS: " + str(static.ARQ_N_RX_FRAMES_PER_BURSTS)) #for l in range(0,len(static.ARQ_RX_BURST_BUFFER)): # print(static.ARQ_RX_BURST_BUFFER[l]) #here we get the total payload for the frame for n_raw_frame in range(1,len(static.ARQ_RX_BURST_BUFFER)): # we need to check if we have a None or received data in list if static.ARQ_RX_BURST_BUFFER[n_raw_frame] != None: burst_frame = static.ARQ_RX_BURST_BUFFER[n_raw_frame] #get burst frame burst_payload = burst_frame[4:] #remove frame type and burst CRC burst_total_payload = burst_total_payload + burst_payload #stick bursts together # ------------------ calculate CRC of BURST burst_payload_crc = helpers.get_crc_16(burst_total_payload) # IF BURST CRC IS CORRECT, APPEND BURST TO BUFFER AND SEND ACK FRAME if burst_payload_crc == data_in[2:4]: #logging.info("ARQ BURST CRC ARE EQUAL!") static.ARQ_RX_FRAME_BUFFER.append(burst_total_payload) # IF CRC TRUE APPEND burst_total_payload TO ARQ_RX_FRAME_BUFFER #BUILDING ACK FRAME ----------------------------------------------- ack_payload = bytes(burst_payload_crc) ack_frame = b'<'+ bytes(burst_payload_crc) # < = 60 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 ----------------------------------------------- # we need to wait until RX is finished on TX side --> seems to be not necessary if modulation buffer allocation for TX is correct #time.sleep(2) #3.8 logging.info("ARQ | TX | SENDING ARQ BURST ACK [" + str(data_in[1:3]) +"]") modem.transmit_arq_ack(ack_buffer) # ---------------------------------------------------------------- static.ARQ_RX_BURST_BUFFER = [] # CLEAR RX BURST BUFFER AFTER SENDING DATA else: #IF burst payload crc and input crc are NOT equal logging.info("ARQ BURST CRC NOT EQUAL! [" + str(data_in[2:4]) + "]") static.ARQ_RX_BURST_BUFFER = [] #erase 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] # -------- DETECT IF WE ALREADY RECEIVED A FRAME HEADER THEN SAVE DATA TO GLOBALS if complete_frame[4:6].startswith(static.FRAME_BOF) or burst_total_payload[4:6].startswith(static.FRAME_BOF): #5:7 static.FRAME_CRC = complete_frame[2:4] static.ARQ_FRAME_BOF_RECEIVED = True # -------- DETECT IF WE HAVE ALREADY RECEIVED THE LAST FRAME if burst_total_payload.rstrip(b'\x00').endswith(static.FRAME_EOF): static.ARQ_FRAME_EOF_RECEIVED = True #check if Begin of Frame BOF and End of Frame EOF are received, then start calculating CRC and sticking everything together if static.ARQ_FRAME_BOF_RECEIVED == True and static.ARQ_FRAME_EOF_RECEIVED == True: # 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) #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("ARQ | RX | DATA FRAME SUCESSFULLY RECEIVED! - TIME TO PARTY") static.RX_BUFFER.append(frame_payload) # clearing buffers static.ARQ_RX_FRAME_BUFFER = [] static.ARQ_FRAME_BOF_RECEIVED = False static.ARQ_FRAME_EOF_RECEIVED = False print("----------------------------------------------------------------") print(static.RX_BUFFER[-1]) print("----------------------------------------------------------------") # HERE: WE COULD SEND ACK FOR TOTAL FRAME else: logging.info("ARQ | RX | DATA FRAME NOT SUCESSFULLY RECEIVED!") print("ARQ FRAME PAYLOAD CRC: " + str(frame_payload_crc)) print("ARQ FRAME PAYLOAD: " + str(frame_payload)) print("DATA FRAME: " + str(complete_frame)) #static.ARQ_RX_FRAME_BUFFER = [] # ---> BUFFER ERST LÖSCHEN WENN MINDESTANZAHL AN BURSTS ERHALTEN WORDEN SIND def ack_received(): logging.info("ARQ | RX | ACK RCVD!") static.ARQ_ACK_TIMEOUT = 1 #Force timer to stop waiting static.ARQ_ACK_RECEIVED = 1 #Force data loops of TNC to stop and continue with next frame def transmit(data_out): static.ARQ_PAYLOAD_PER_FRAME = static.FREEDV_DATA_PAYLOAD_PER_FRAME - 4 #3 ohne ARQ_TX_N_FRAMES_PER_BURST 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 #print(static.FREEDV_DATA_PAYLOAD_PER_FRAME) #print(static.ARQ_PAYLOAD_PER_FRAME) #print(n_bursts_prediction) n_bursts_prediction = n_bursts_prediction.to_bytes(2, byteorder='big') #65535 frame_payload_crc = helpers.get_crc_16(data_out) # This is the total frame with frame header, which will be send data_out = n_bursts_prediction + frame_payload_crc + static.FRAME_BOF + data_out + static.FRAME_EOF # 2 2 2 N 2 #print(data_out) #print(len(data_out)) #print(static.ARQ_PAYLOAD_PER_FRAME) # --------------------------------------------- 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) #print(static.TX_BUFFER) logging.info("ARQ | TX | TOTAL PAYLOAD BYTES/FRAMES TO SEND: " + str(len(data_out)) + " / " + str(static.TX_BUFFER_SIZE)) # --------------------------------------------- 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)) static.ARQ_TX_N_FRAMES_PER_BURST = get_n_frames_per_burst() # ----------- CREATE FRAME TOTAL PAYLOAD TO BE ABLE TO CREATE CRC FOR IT burst_total_payload = bytearray() try: # DETECT IF LAST BURST TO PREVENT INDEX ERROR OF BUFFER for i in range(static.ARQ_TX_N_FRAMES_PER_BURST): # Loop through TX_BUFFER LIST # make sure we have always a filled buffer with the length of payload per frame 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 # get frame from TX_BUFFER burst_total_payload = burst_total_payload + burst_payload # append single frame to total payload buffer except IndexError: # IF LAST BURST DETECTED BUILD CRC WITH LESS FRAMES AND SET static.ARQ_TX_N_FRAMES_PER_BURST 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_PER_BURST > static.TX_BUFFER_SIZE): #WE CANT DO MODULO 0 --> CHECK IF FIRST FRAME == LAST FRAME static.ARQ_TX_N_FRAMES_PER_BURST = static.TX_BUFFER_SIZE elif static.ARQ_N_SENT_FRAMES == 1 and (static.ARQ_TX_N_FRAMES_PER_BURST > static.TX_BUFFER_SIZE): # MODULO 1 WILL ALWAYS BE 0 --> THIS FIXES IT static.ARQ_TX_N_FRAMES_PER_BURST = static.TX_BUFFER_SIZE - static.ARQ_N_SENT_FRAMES else: static.ARQ_TX_N_FRAMES_PER_BURST = (static.TX_BUFFER_SIZE % static.ARQ_N_SENT_FRAMES) print("ARQ_TX_N_FRAMES_PER_BURST OF LAST BURST: " + str(static.ARQ_TX_N_FRAMES_PER_BURST)) for i in range(static.ARQ_TX_N_FRAMES_PER_BURST): #bytearray(b'111111111111111111111111222222222222222222222222') # make sure we have always a filled buffer with the length of payload per frame 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 # get frame from TX_BUFFER burst_total_payload = burst_total_payload + burst_payload # append single frame to total payload buffer #print(burst_total_payload) # ----------- GENERATE PAYLOAD CRC FOR ARQ_TX_N_FRAMES_PER_BURST static.ARQ_BURST_PAYLOAD_CRC = helpers.get_crc_16(burst_total_payload) #--------------------------------------------- N ATTEMPTS TO SEND BURSTS IF ACK RECEPTION FAILS for static.TX_N_RETRIES in range(static.TX_N_MAX_RETRIES): print("SENDING") # lets start a thread to transmit nonblocking TRANSMIT_ARQ_BURST_THREAD = threading.Thread(target=modem.transmit_arq_burst, name="TRANSMIT_ARQ_BURST") TRANSMIT_ARQ_BURST_THREAD.start() # lets wait during sending. After sending is finished we will continue while static.ARQ_STATE == 'SENDING_DATA': time.sleep(0.05) # --------------------------- START TIMER FOR WAITING FOR ACK ---> IF TIMEOUT REACHED, ACK_TIMEOUT = 1 #reset timer and ack state static.ARQ_ACK_RECEIVED = 0 static.ARQ_ACK_TIMEOUT = 0 logging.info("ARQ | WAITING FOR ACK") static.ARQ_STATE = 'RECEIVING_ACK' timer = threading.Timer(static.ARQ_ACK_TIMEOUT_SECONDS, arq_ack_timeout) timer.start() # waiting the other way... #starttimer = time.time() + static.ARQ_ACK_TIMEOUT_SECONDS #while starttimer > time.time() and static.ARQ_ACK_RECEIVED == 0: # #print(str(starttimer - time.time())) # pass #else: # static.ARQ_ACK_TIMEOUT = 1 #static.MODEM_RECEIVE = False # --------------------------- WHILE TIMEOUT NOT REACHED AND NO ACK RECEIVED --> LISTEN while static.ARQ_ACK_TIMEOUT == 0 and static.ARQ_ACK_RECEIVED == 0: time.sleep(0.01) # lets reduce CPU load a little bit print(static.ARQ_STATE) #--------------- BREAK LOOP IF ACK HAS BEEN RECEIVED if static.ARQ_ACK_RECEIVED == 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_PER_BURST break if static.ARQ_ACK_RECEIVED == 0 and static.ARQ_ACK_TIMEOUT == 1: logging.info("ARQ | ACK TIMEOUT | SENDING ARQ BURST AGAIN") # ----------- if no ACK received and out of retries.....stop frame sending #if static.ARQ_ACK_RECEIVED == 0 and static.ARQ_ACK_TIMEOUT == 1: # logging.info("ARQ | TX | NO ACK RECEIVED | DATA 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(3) # IF TX BUFFER IS EMPTY / ALL FRAMES HAVE BEEN SENT --> HERE WE COULD ADD AN static.VAR for IDLE STATE #logging.info("ARQ | TX | FRAME SUCESSFULLY TRANSMITTED! - TIME TO PARTY") logging.info("ARQ | TX | BUFFER EMPTY") print(static.ARQ_N_SENT_FRAMES) print(static.ARQ_TX_N_FRAMES_PER_BURST) # - RESET COUNTERS static.ARQ_N_SENT_FRAMES = 0 static.ARQ_TX_N_FRAMES_PER_BURST = 0 static.ARQ_ACK_RECEIVED = 0 # 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) n_frames_per_burst = 2 return n_frames_per_burst