def pack(self): """ Packs the header and payload and adds the CRC. Header and payload fields are packed using data in the class variables. Returns the packed packet """ packet = self.pack_header() + self.payload return gru.gen_and_append_crc32(packet)
def make_packet(payload, samples_per_symbol, bits_per_symbol, pad_for_usrp=True, whitener_offset=0, whitening=True): """ Build a packet, given access code, payload, and whitener offset @param payload: packet payload, len [0, 4096] @param samples_per_symbol: samples per symbol (needed for padding calculation) @type samples_per_symbol: int @param bits_per_symbol: (needed for padding calculation) @type bits_per_symbol: int @param whitener_offset offset into whitener string to use [0-16) @param whitening: Turn whitener on or off @type whitening: bool Packet will have access code at the beginning, followed by length, payload and finally CRC-32. """ if not whitener_offset >=0 and whitener_offset < 16: raise ValueError, "whitener_offset must be between 0 and 15, inclusive (%i)" % (whitener_offset,) payload_with_crc = gru.gen_and_append_crc32(payload) #print "outbound crc =", string_to_hex_list(payload_with_crc[-4:]) L = len(payload_with_crc) MAXLEN = len(random_mask_tuple) if L > MAXLEN: raise ValueError, "len(payload) must be in [0, %d]" % (MAXLEN,) pkt_hd = make_header(L, whitener_offset) pkt_dt = ''.join((payload_with_crc, '\x55')) packet_length = len(pkt_hd) + len(pkt_dt) if pad_for_usrp: usrp_packing = _npadding_bytes(packet_length, samples_per_symbol, bits_per_symbol) * '\x55' pkt_dt = pkt_dt + usrp_packing if(whitening): pkt = pkt_hd + whiten(pkt_dt, whitener_offset) else: pkt = pkt_hd + pkt_dt if 0: #print "make_packet: len(pkt) =", len(pkt) print "\n" print "len(pkt_hd) = %d + len(pkt_dt)= %d ==> len(pkt)= %d" % (len(pkt_hd), len(pkt_dt), len(pkt)) print "len(payload)=", len(payload) print "len(payload_with_crc)=", len(payload_with_crc) print "plus 1 byte of preamble" print "\n" print "samples_per_symbol=", samples_per_symbol print "bits_per_symbol=", bits_per_symbol return pkt
def make_packet(payload, samples_per_symbol, bits_per_symbol, access_code=default_access_code, pad_for_usrp=True, whitener_offset=0, whitening=True): """ Build a packet, given access code, payload, and whitener offset @param payload: packet payload, len [0, 4096] @param samples_per_symbol: samples per symbol (needed for padding calculation) @type samples_per_symbol: int @param bits_per_symbol: (needed for padding calculation) @type bits_per_symbol: int @param access_code: string of ascii 0's and 1's @param whitener_offset offset into whitener string to use [0-16) Packet will have access code at the beginning, followed by length, payload and finally CRC-32. """ if not is_1_0_string(access_code): raise ValueError, "access_code must be a string containing only 0's and 1's (%r)" % (access_code,) if not whitener_offset >=0 and whitener_offset < 16: raise ValueError, "whitener_offset must be between 0 and 15, inclusive (%i)" % (whitener_offset,) (packed_access_code, padded) = conv_1_0_string_to_packed_binary_string(access_code) (packed_preamble, ignore) = conv_1_0_string_to_packed_binary_string(preamble) payload_with_crc = gru.gen_and_append_crc32(payload) #print "outbound crc =", string_to_hex_list(payload_with_crc[-4:]) print "outbound payload =", [(i, bin(int(string_to_hex_list(i)[0],16))) for i in payload_with_crc[1:-4]] L = len(payload_with_crc) MAXLEN = len(random_mask_tuple) if L > MAXLEN: raise ValueError, "len(payload) must be in [0, %d]" % (MAXLEN,) if whitening: pkt = ''.join((packed_preamble, packed_access_code, make_header(L, whitener_offset), whiten(payload_with_crc, whitener_offset), '\x55')) else: pkt = ''.join((packed_preamble, packed_access_code, make_header(L, whitener_offset), (payload_with_crc), '\x55')) if pad_for_usrp: pkt = pkt + (_npadding_bytes(len(pkt), int(samples_per_symbol), bits_per_symbol) * '\x55') #print "make_packet: len(pkt) =", len(pkt) return pkt
def make_packet(payload, samples_per_symbol, bits_per_symbol, access_code=default_access_code, pad_for_usrp=True, whitener_offset=0, whitening=True): """ Build a packet, given access code, payload, and whitener offset @param payload: packet payload, len [0, 4096] @param samples_per_symbol: samples per symbol (needed for padding calculation) @type samples_per_symbol: int @param bits_per_symbol: (needed for padding calculation) @type bits_per_symbol: int @param access_code: string of ascii 0's and 1's @param whitener_offset offset into whitener string to use [0-16) Packet will have access code at the beginning, followed by length, payload and finally CRC-32. """ if not is_1_0_string(access_code): raise ValueError, "access_code must be a string containing only 0's and 1's (%r)" % (access_code,) if not whitener_offset >=0 and whitener_offset < 16: raise ValueError, "whitener_offset must be between 0 and 15, inclusive (%i)" % (whitener_offset,) (packed_access_code, padded) = conv_1_0_string_to_packed_binary_string(access_code) (packed_preamble, ignore) = conv_1_0_string_to_packed_binary_string(preamble) payload_with_crc = gru.gen_and_append_crc32(payload) #print "outbound crc =", string_to_hex_list(payload_with_crc[-4:]) L = len(payload_with_crc) MAXLEN = len(random_mask_tuple) if L > MAXLEN: raise ValueError, "len(payload) must be in [0, %d]" % (MAXLEN,) if whitening: pkt = ''.join((packed_preamble, packed_access_code, make_header(L, whitener_offset), whiten(payload_with_crc, whitener_offset), '\x55')) else: pkt = ''.join((packed_preamble, packed_access_code, make_header(L, whitener_offset), (payload_with_crc), '\x55')) if pad_for_usrp: pkt = pkt + (_npadding_bytes(len(pkt), int(samples_per_symbol), bits_per_symbol) * '\x55') #print "make_packet: len(pkt) =", len(pkt) return pkt
def make_packet(payload, samples_per_symbol, bits_per_symbol, pad_for_usrp=True, whitener_offset=0, whitening=True): """ Build a packet, given access code, payload, and whitener offset @param payload: packet payload, len [0, 4096] @param samples_per_symbol: samples per symbol (needed for padding calculation) @type samples_per_symbol: int @param bits_per_symbol: (needed for padding calculation) @type bits_per_symbol: int @param whitener_offset offset into whitener string to use [0-16) @param whitening: Turn whitener on or off @type whitening: bool Packet will have access code at the beginning, followed by length, payload and finally CRC-32. """ if not whitener_offset >=0 and whitener_offset < 16: raise ValueError, "whitener_offset must be between 0 and 15, inclusive (%i)" % (whitener_offset,) payload_with_crc = gru.gen_and_append_crc32(payload) #print "outbound crc =", string_to_hex_list(payload_with_crc[-4:]) L = len(payload_with_crc) MAXLEN = len(random_mask_tuple) if L > MAXLEN: raise ValueError, "len(payload) must be in [0, %d]" % (MAXLEN,) pkt_hd = make_header(L, whitener_offset) pkt_dt = ''.join((payload_with_crc, '\x55')) packet_length = len(pkt_hd) + len(pkt_dt) if pad_for_usrp: usrp_packing = _npadding_bytes(packet_length, samples_per_symbol, bits_per_symbol) * '\x55' pkt_dt = pkt_dt + usrp_packing if(whitening): pkt = pkt_hd + whiten(pkt_dt, whitener_offset) else: pkt = pkt_hd + pkt_dt #print "make_packet: len(pkt) =", len(pkt) return pkt