diff options
Diffstat (limited to 'gnuradio-core/src')
| -rw-r--r-- | gnuradio-core/src/lib/general/gr_framer_sink_1.cc | 17 | ||||
| -rw-r--r-- | gnuradio-core/src/lib/general/gr_framer_sink_1.h | 11 | ||||
| -rw-r--r-- | gnuradio-core/src/python/gnuradio/blksimpl/pkt.py | 17 | ||||
| -rw-r--r-- | gnuradio-core/src/python/gnuradio/packet_utils.py | 31 |
4 files changed, 48 insertions, 28 deletions
diff --git a/gnuradio-core/src/lib/general/gr_framer_sink_1.cc b/gnuradio-core/src/lib/general/gr_framer_sink_1.cc index d6f87df1e..1d939adbd 100644 --- a/gnuradio-core/src/lib/general/gr_framer_sink_1.cc +++ b/gnuradio-core/src/lib/general/gr_framer_sink_1.cc @@ -52,13 +52,14 @@ gr_framer_sink_1::enter_have_sync() } inline void -gr_framer_sink_1::enter_have_header(int payload_len) +gr_framer_sink_1::enter_have_header(int payload_len, int whitener_offset) { if (VERBOSE) - fprintf(stderr, "@ enter_have_header (payload_len = %d)\n", payload_len); + fprintf(stderr, "@ enter_have_header (payload_len = %d) (offset = %d)\n", payload_len, whitener_offset); d_state = STATE_HAVE_HEADER; d_packetlen = payload_len; + d_packet_whitener_offset = whitener_offset; d_packetlen_cnt = 0; d_packet_byte = 0; d_packet_byte_index = 0; @@ -125,11 +126,10 @@ gr_framer_sink_1::work (int noutput_items, // we have a full header, check to see if it has been received properly if (header_ok()){ - int payload_len = header_payload_len(); - if (payload_len <= MAX_PKT_LEN) // reasonable? - enter_have_header(payload_len); // yes. - else - enter_search(); // no. + int payload_len; + int payload_offset; + header_payload(&payload_len, &payload_offset); + enter_have_header(payload_len, payload_offset); } else enter_search(); // no. @@ -151,7 +151,8 @@ gr_framer_sink_1::work (int noutput_items, if (d_packetlen_cnt == d_packetlen){ // packet is filled // build a message - gr_message_sptr msg = gr_make_message(0, 0, 0, d_packetlen_cnt); + // NOTE: passing header field as arg1 is not scalable + gr_message_sptr msg = gr_make_message(0, d_packet_whitener_offset, 0, d_packetlen_cnt); memcpy(msg->msg(), d_packet, d_packetlen_cnt); d_target_queue->insert_tail(msg); // send it diff --git a/gnuradio-core/src/lib/general/gr_framer_sink_1.h b/gnuradio-core/src/lib/general/gr_framer_sink_1.h index dab346755..ba50184b8 100644 --- a/gnuradio-core/src/lib/general/gr_framer_sink_1.h +++ b/gnuradio-core/src/lib/general/gr_framer_sink_1.h @@ -70,6 +70,7 @@ class gr_framer_sink_1 : public gr_sync_block unsigned char d_packet_byte; // byte being assembled int d_packet_byte_index; // which bit of d_packet_byte we're working on int d_packetlen; // length of packet + int d_packet_whitener_offset; // offset into whitener string to use int d_packetlen_cnt; // how many so far protected: @@ -77,7 +78,7 @@ class gr_framer_sink_1 : public gr_sync_block void enter_search(); void enter_have_sync(); - void enter_have_header(int payload_len); + void enter_have_header(int payload_len, int whitener_offset); bool header_ok() { @@ -85,11 +86,13 @@ class gr_framer_sink_1 : public gr_sync_block return ((d_header >> 16) ^ (d_header & 0xffff)) == 0; } - int header_payload_len() + void header_payload(int *len, int *offset) { // header consists of two 16-bit shorts in network byte order - int t = (d_header >> 16) & 0xffff; - return t; + // payload length is lower 12 bits + // whitener offset is upper 4 bits + *len = (d_header >> 16) & 0x0fff; + *offset = (d_header >> 28) & 0x000f; } public: diff --git a/gnuradio-core/src/python/gnuradio/blksimpl/pkt.py b/gnuradio-core/src/python/gnuradio/blksimpl/pkt.py index a1ece893d..96b48657f 100644 --- a/gnuradio-core/src/python/gnuradio/blksimpl/pkt.py +++ b/gnuradio-core/src/python/gnuradio/blksimpl/pkt.py @@ -36,7 +36,7 @@ class mod_pkts(gr.hier_block): Send packets by calling send_pkt """ - def __init__(self, fg, modulator, access_code=None, msgq_limit=2, pad_for_usrp=True): + def __init__(self, fg, modulator, access_code=None, msgq_limit=2, pad_for_usrp=True, use_whitener_offset=False): """ Hierarchical block for sending packets @@ -52,12 +52,15 @@ class mod_pkts(gr.hier_block): @param msgq_limit: maximum number of messages in message queue @type msgq_limit: int @param pad_for_usrp: If true, packets are padded such that they end up a multiple of 128 samples - + @param use_whitener_offset: If true, start of whitener XOR string is incremented each packet + See gmsk_mod for remaining parameters """ self._modulator = modulator self._pad_for_usrp = pad_for_usrp - + self._use_whitener_offset = use_whitener_offset + self._whitener_offset = 0 + if access_code is None: access_code = packet_utils.default_access_code if not packet_utils.is_1_0_string(access_code): @@ -84,9 +87,13 @@ class mod_pkts(gr.hier_block): self._modulator.samples_per_symbol(), self._modulator.bits_per_symbol(), self._access_code, - self._pad_for_usrp) + self._pad_for_usrp, + self._whitener_offset) #print "pkt =", string_to_hex_list(pkt) msg = gr.message_from_string(pkt) + if self._use_whitener_offset is True: + self._whitener_offset = (self._whitener_offset + 1) % 16 + self._pkt_input.msgq().insert_tail(msg) @@ -151,6 +158,6 @@ class _queue_watcher_thread(_threading.Thread): def run(self): while self.keep_running: msg = self.rcvd_pktq.delete_head() - ok, payload = packet_utils.unmake_packet(msg.to_string()) + ok, payload = packet_utils.unmake_packet(msg.to_string(), int(msg.arg1())) if self.callback: self.callback(ok, payload) diff --git a/gnuradio-core/src/python/gnuradio/packet_utils.py b/gnuradio-core/src/python/gnuradio/packet_utils.py index 59b135366..182c80cdc 100644 --- a/gnuradio-core/src/python/gnuradio/packet_utils.py +++ b/gnuradio-core/src/python/gnuradio/packet_utils.py @@ -86,22 +86,26 @@ def string_to_hex_list(s): return map(lambda x: hex(ord(x)), s) -def whiten(s): +def whiten(s, o): sa = Numeric.fromstring(s, Numeric.UnsignedInt8) - z = sa ^ random_mask_vec8[0:len(sa)] + z = sa ^ random_mask_vec8[o:len(sa)+o] return z.tostring() -def dewhiten(s): - return whiten(s) # self inverse +def dewhiten(s, o): + return whiten(s, o) # self inverse -def make_header(payload_len): - return struct.pack('!HH', payload_len, payload_len) +def make_header(payload_len, whitener_offset=0): + # Upper nibble is offset, lower 12 bits is len + val = ((whitener_offset & 0xf) << 12) | (payload_len & 0x0fff) + #print "offset =", whitener_offset, " len =", payload_len, " val=", val + return struct.pack('!HH', val, val) def make_packet(payload, samples_per_symbol, bits_per_symbol, - access_code=default_access_code, pad_for_usrp=True): + access_code=default_access_code, pad_for_usrp=True, + whitener_offset=0): """ - Build a packet, given access code and payload. + 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) @@ -109,6 +113,7 @@ def make_packet(payload, samples_per_symbol, bits_per_symbol, @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. @@ -116,6 +121,9 @@ def make_packet(payload, samples_per_symbol, bits_per_symbol, 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) @@ -127,7 +135,8 @@ def make_packet(payload, samples_per_symbol, bits_per_symbol, if L > MAXLEN: raise ValueError, "len(payload) must be in [0, %d]" % (MAXLEN,) - pkt = ''.join((packed_preamble, packed_access_code, make_header(L), whiten(payload_with_crc), '\x55')) + pkt = ''.join((packed_preamble, packed_access_code, make_header(L, whitener_offset), + whiten(payload_with_crc, whitener_offset), '\x55')) if pad_for_usrp: pkt = pkt + (_npadding_bytes(len(pkt), samples_per_symbol, bits_per_symbol) * '\x55') @@ -156,13 +165,13 @@ def _npadding_bytes(pkt_byte_len, samples_per_symbol, bits_per_symbol): return byte_modulus - r -def unmake_packet(whitened_payload_with_crc): +def unmake_packet(whitened_payload_with_crc, whitener_offset=0): """ Return (ok, payload) @param whitened_payload_with_crc: string """ - payload_with_crc = dewhiten(whitened_payload_with_crc) + payload_with_crc = dewhiten(whitened_payload_with_crc, whitener_offset) ok, payload = gru.check_crc32(payload_with_crc) if 0: |