Add AX.25 decoder with legacy support for the hardware radios
This commit is contained in:
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commit
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File diff suppressed because it is too large
Load Diff
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@ -23,7 +23,6 @@ install(FILES
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satnogs_multi_format_msg_sink.xml
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satnogs_cw_to_symbol.xml
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satnogs_sine_matched_filter_ff.xml
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satnogs_ax25_decoder_b.xml
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satnogs_udp_msg_source.xml
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satnogs_debug_msg_source.xml
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satnogs_json_to_ecss_src.xml
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@ -37,5 +36,6 @@ install(FILES
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satnogs_upsat_transmitter.xml
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satnogs_coarse_doppler_correction_cc.xml
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satnogs_debug_msg_source_raw.xml
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satnogs_ax25_encoder_mb.xml DESTINATION share/gnuradio/grc/blocks
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satnogs_ax25_encoder_mb.xml
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satnogs_ax25_decoder_bm.xml DESTINATION share/gnuradio/grc/blocks
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)
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@ -1,20 +1,22 @@
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<?xml version="1.0"?>
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<block>
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<name>AX.25 Decoder</name>
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<key>satnogs_ax25_decoder_b</key>
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<key>satnogs_ax25_decoder_bm</key>
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<category>satnogs</category>
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<import>import satnogs</import>
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<make>satnogs.ax25_decoder_b($addr, $ssid, $promisc)</make>
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<make>satnogs.ax25_decoder_bm($addr, $ssid, $promisc, $descrambling, $max_frame_len)</make>
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<param>
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<name>Receiver Callsign</name>
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<key>addr</key>
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<value>'GND'</value>
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<type>string</type>
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</param>
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<param>
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<name>Receiver SSID</name>
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<key>ssid</key>
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<value>0</value>
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<type>int</type>
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</param>
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@ -33,6 +35,27 @@
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</option>
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</param>
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<param>
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<name>G3RUH descrambling</name>
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<key>descrambling</key>
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<type>enum</type>
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<option>
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<name>Yes</name>
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<key>True</key>
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</option>
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<option>
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<name>No</name>
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<key>False</key>
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</option>
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</param>
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<param>
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<name>Maximum frame length</name>
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<key>max_frame_len</key>
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<value>256</value>
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<type>int</type>
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</param>
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<sink>
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<name>in</name>
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<type>byte</type>
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@ -42,4 +65,11 @@
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<name>pdu</name>
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<type>message</type>
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</source>
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<source>
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<name>failed_pdu</name>
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<type>message</type>
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<optional>1</optional>
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</source>
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</block>
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@ -34,7 +34,6 @@ install(FILES
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cw_to_symbol.h
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sine_matched_filter_ff.h
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utils.h
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ax25_decoder_b.h
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udp_msg_source.h
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debug_msg_source.h
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json_to_ecss_src.h
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@ -49,5 +48,6 @@ install(FILES
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udp_msg_sink.h
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coarse_doppler_correction_cc.h
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debug_msg_source_raw.h
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ax25_encoder_mb.h DESTINATION include/satnogs
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ax25_encoder_mb.h
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ax25_decoder_bm.h DESTINATION include/satnogs
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)
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@ -1,56 +0,0 @@
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/* -*- c++ -*- */
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/*
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* gr-satnogs: SatNOGS GNU Radio Out-Of-Tree Module
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*
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* Copyright (C) 2016, Libre Space Foundation <http://librespacefoundation.org/>
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#ifndef INCLUDED_SATNOGS_AX25_DECODER_B_H
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#define INCLUDED_SATNOGS_AX25_DECODER_B_H
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#include <satnogs/api.h>
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#include <gnuradio/sync_block.h>
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namespace gr {
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namespace satnogs {
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/*!
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* \brief AX.25 decoding block
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* \ingroup satnogs
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*
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*/
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class SATNOGS_API ax25_decoder_b : virtual public gr::sync_block
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{
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public:
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typedef boost::shared_ptr<ax25_decoder_b> sptr;
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/**
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* AX.25 decoder block.
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*
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* @param addr the Callsign of the receiver
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* @param ssid the SSID of the receiver
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* @param promisc if set to true, all the successfully decoded frames
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* are forwarded. Otherwise, only those that have as destination address
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* and SSID specified by the addr and ssid parameters respectively.
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*/
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static sptr make(std::string addr, uint8_t ssid, bool promisc=true);
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};
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} // namespace satnogs
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} // namespace gr
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#endif /* INCLUDED_SATNOGS_AX25_DECODER_B_H */
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@ -0,0 +1,89 @@
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/* -*- c++ -*- */
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/*
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* gr-satnogs: SatNOGS GNU Radio Out-Of-Tree Module
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*
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* Copyright (C) 2016, Libre Space Foundation <http://librespacefoundation.org/>
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#ifndef INCLUDED_SATNOGS_AX25_DECODER_BM_H
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#define INCLUDED_SATNOGS_AX25_DECODER_BM_H
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#include <satnogs/api.h>
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#include <gnuradio/sync_block.h>
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namespace gr
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{
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namespace satnogs
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{
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/*!
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* \brief AX.25 decoder that supports the legacy hardware radios.
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*
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* This block takes as input a quadrature demodulated bit stream.
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* Each byte should contains only one bit of information at the LSB.
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*
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* The block will try to find an AX.25 frame. If the frame pass the
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* CRC check then a blob PMT message is produced at the message output
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* indicated with name 'out'. Otherwise if the frame did not pass the
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* CRC check or the size was invalid, a blob PMT message is generated at
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* the output port with the name 'fail'. This will help to recover at least
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* some bytes from a corrupted message.
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*
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* The block also supports destination callsign check. Only frames with
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* the right destination Callsign will be accepted. This feature can be
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* disabled using the promisc parameter.
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*
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* \ingroup satnogs
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*
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*/
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class SATNOGS_API ax25_decoder_bm : virtual public gr::sync_block
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{
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public:
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typedef boost::shared_ptr<ax25_decoder_bm> sptr;
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/**
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* This block takes as input a quadrature demodulated bit stream.
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* Each byte should contains only one bit of information at the LSB.
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*
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* The block will try to find an AX.25 frame. If the frame pass the
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* CRC check then a blob PMT message is produced at the message output
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* indicated with name 'pdu'. Otherwise if the frame did not pass the
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* CRC check or the size was invalid, a blob PMT message is generated at
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* the output port with the name 'failed_pdu'.
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* This will help to recover at least some bytes from a corrupted message.
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*
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* The block also supports destination callsign check. Only frames with
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* the right destination Callsign will be accepted. This feature can be
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* disabled using the promisc parameter.
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* @param addr the Callsign of the receiver
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* @param ssid the SSID of the receiver
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* @param promisc if set to yes, the Callsign check is disabled
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* @param descramble if set to yes, the data will be descrambled prior
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* decoding using the G3RUH self-synchronizing descrambler.
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* @param max_frame_len the maximum allowed frame length
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* @return
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*/
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static sptr
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make (const std::string& addr, uint8_t ssid, bool promisc = false,
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bool descramble = true,
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size_t max_frame_len = 512);
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};
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} // namespace satnogs
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} // namespace gr
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#endif /* INCLUDED_SATNOGS_AX25_DECODER_BM_H */
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@ -32,7 +32,6 @@ list(APPEND satnogs_sources
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multi_format_msg_sink_impl.cc
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cw_to_symbol_impl.cc
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sine_matched_filter_ff_impl.cc
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ax25_decoder_b_impl.cc
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udp_msg_source_impl.cc
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debug_msg_source_impl.cc
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tcp_rigctl_msg_source_impl.cc
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@ -47,7 +46,8 @@ list(APPEND satnogs_sources
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udp_msg_sink_impl.cc
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coarse_doppler_correction_cc_impl.cc
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debug_msg_source_raw_impl.cc
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ax25_encoder_mb_impl.cc )
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ax25_encoder_mb_impl.cc
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ax25_decoder_bm_impl.cc )
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set(satnogs_sources "${satnogs_sources}" PARENT_SCOPE)
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if(NOT satnogs_sources)
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@ -1,189 +0,0 @@
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/* -*- c++ -*- */
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/*
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* gr-satnogs: SatNOGS GNU Radio Out-Of-Tree Module
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*
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* Copyright (C) 2016, Libre Space Foundation <http://librespacefoundation.org/>
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#include <gnuradio/io_signature.h>
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#include "ax25_decoder_b_impl.h"
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#include <satnogs/log.h>
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namespace gr {
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namespace satnogs {
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ax25_decoder_b::sptr
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ax25_decoder_b::make(std::string addr, uint8_t ssid, bool promisc)
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{
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return gnuradio::get_initial_sptr
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(new ax25_decoder_b_impl(addr, ssid, promisc));
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}
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/*
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* The private constructor
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*/
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ax25_decoder_b_impl::ax25_decoder_b_impl (std::string addr, uint8_t ssid,
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bool promisc) :
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gr::sync_block ("ax25_decoder_b",
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gr::io_signature::make (1, 1, sizeof(uint8_t)),
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gr::io_signature::make (0, 0, 0)),
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d_promisc(promisc),
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d_state(NO_SYNC),
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d_dec_b(0),
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d_prev_bit(0),
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d_received_bytes(0),
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d_decoded_bits(0),
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d_cont_1(0),
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d_frame_buffer(new uint8_t[AX25_MAX_FRAME_LEN
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+ AX25_MAX_ADDR_LEN
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+ AX25_MAX_CTRL_LEN
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+ sizeof(uint16_t)])
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{
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message_port_register_out (pmt::mp ("pdu"));
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}
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void
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ax25_decoder_b_impl::reset_state ()
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{
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d_state = NO_SYNC;
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d_dec_b = 0;
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d_decoded_bits = 0;
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d_received_bytes = 0;
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d_cont_1 = 0;
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}
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void
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ax25_decoder_b_impl::enter_sync_state ()
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{
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d_state = IN_SYNC;
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d_dec_b = 0;
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d_decoded_bits = 0;
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d_received_bytes = 0;
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d_prev_bit = 0;
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d_cont_1 = 0;
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}
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void
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ax25_decoder_b_impl::update_recv_frame (uint8_t byte)
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{
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uint16_t fcs;
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uint16_t recv_fcs = 0x0;
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if( d_decoded_bits ) {
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return;
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}
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if(byte == AX25_SYNC_FLAG) {
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/* First check if the size of the frame is valid */
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if(d_received_bytes < AX25_MIN_ADDR_LEN + sizeof(uint16_t)){
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reset_state();
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return;
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}
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/* Check if the frame is correct using the FCS field */
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fcs = ax25_fcs (d_frame_buffer, d_received_bytes - sizeof(uint16_t));
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recv_fcs = (((uint16_t) d_frame_buffer[d_received_bytes - 2]) << 8)
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| d_frame_buffer[d_received_bytes - 1];
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if( fcs == recv_fcs ) {
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message_port_pub (
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pmt::mp ("pdu"),
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pmt::make_blob (d_frame_buffer,
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d_received_bytes - sizeof(uint16_t)));
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}
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else {
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LOG_WARN("Wrong FCS: Should be 0%x, computed as 0%x", recv_fcs, fcs);
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}
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LOG_WARN("Frame size %lu", d_received_bytes);
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reset_state();
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}
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else{
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d_frame_buffer[d_received_bytes++] = byte;
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if(d_received_bytes > AX25_MAX_FRAME_LEN){
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LOG_WARN("Maximum frame size reached. Abort decoding this frame");
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reset_state();
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}
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}
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d_dec_b = 0;
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}
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/*
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* Our virtual destructor.
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*/
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ax25_decoder_b_impl::~ax25_decoder_b_impl()
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{
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delete[] d_frame_buffer;
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}
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int
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ax25_decoder_b_impl::work(int noutput_items,
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gr_vector_const_void_star &input_items,
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gr_vector_void_star &output_items)
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{
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int i;
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const uint8_t *in = (const uint8_t *) input_items[0];
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for (i = 0; i < noutput_items; i++) {
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switch (d_state)
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{
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case NO_SYNC:
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d_dec_b = (d_dec_b << 1) | in[i];
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/*
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* If the decoder find the sync flag of the AX.25 frame start the
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* decoding process
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*/
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if(d_dec_b == AX25_SYNC_FLAG){
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enter_sync_state();
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}
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break;
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case IN_SYNC:
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if(in[i]){
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if(d_prev_bit) {
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d_cont_1++;
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}
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else {
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d_cont_1 = 1;
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}
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d_dec_b |= 1 << d_decoded_bits;
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d_decoded_bits = (d_decoded_bits + 1) % 8;
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update_recv_frame(d_dec_b);
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d_prev_bit = 1;
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}
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else{
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/* Check if this a stuffed zero bit */
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if(d_cont_1 < 5) {
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d_decoded_bits = (d_decoded_bits + 1) % 8;
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update_recv_frame(d_dec_b);
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}
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d_prev_bit = 0;
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d_cont_1 = 0;
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}
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break;
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default:
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LOG_ERROR("Invalid decoding state");
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}
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}
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return noutput_items;
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}
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} /* namespace satnogs */
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} /* namespace gr */
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|
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@ -0,0 +1,360 @@
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/* -*- c++ -*- */
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/*
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* gr-satnogs: SatNOGS GNU Radio Out-Of-Tree Module
|
||||
*
|
||||
* Copyright (C) 2016, Libre Space Foundation <http://librespacefoundation.org/>
|
||||
*
|
||||
* This program is free software: you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation, either version 3 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
*/
|
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|
||||
#ifdef HAVE_CONFIG_H
|
||||
#include "config.h"
|
||||
#endif
|
||||
|
||||
#include <gnuradio/io_signature.h>
|
||||
#include <satnogs/log.h>
|
||||
#include <satnogs/ax25.h>
|
||||
#include "ax25_decoder_bm_impl.h"
|
||||
|
||||
namespace gr
|
||||
{
|
||||
namespace satnogs
|
||||
{
|
||||
|
||||
ax25_decoder_bm::sptr
|
||||
ax25_decoder_bm::make (const std::string& addr, uint8_t ssid, bool promisc,
|
||||
bool descramble, size_t max_frame_len)
|
||||
{
|
||||
return gnuradio::get_initial_sptr (
|
||||
new ax25_decoder_bm_impl (addr, ssid, promisc,
|
||||
descramble, max_frame_len));
|
||||
}
|
||||
|
||||
/*
|
||||
* The private constructor
|
||||
*/
|
||||
ax25_decoder_bm_impl::ax25_decoder_bm_impl (const std::string& addr,
|
||||
uint8_t ssid, bool promisc,
|
||||
bool descramble,
|
||||
size_t max_frame_len) :
|
||||
gr::sync_block ("ax25_decoder_bm",
|
||||
gr::io_signature::make (1, 1, sizeof(uint8_t)),
|
||||
gr::io_signature::make (0, 0, 0)),
|
||||
d_promisc (promisc),
|
||||
d_descramble (descramble),
|
||||
d_max_frame_len (max_frame_len),
|
||||
d_state (NO_SYNC),
|
||||
d_dec_b (0),
|
||||
d_prev_bit_nrzi(0),
|
||||
d_received_bytes (0),
|
||||
d_decoded_bits (0),
|
||||
d_lfsr(0x21, 0x0, 16),
|
||||
d_frame_buffer (
|
||||
new uint8_t[max_frame_len + AX25_MAX_ADDR_LEN
|
||||
+ AX25_MAX_CTRL_LEN + sizeof(uint16_t)])
|
||||
{
|
||||
/* Valid PDUs output message port */
|
||||
message_port_register_out (pmt::mp ("pdu"));
|
||||
/*
|
||||
* Valid invalid (wrong CRC, different destination Callsign/SSID,
|
||||
* wrong frame size)PDUs output message port
|
||||
*/
|
||||
message_port_register_out (pmt::mp ("failed_pdu"));
|
||||
}
|
||||
|
||||
void
|
||||
ax25_decoder_bm_impl::descramble_and_decode (const uint8_t* in,
|
||||
size_t nitems)
|
||||
{
|
||||
size_t i;
|
||||
uint8_t descr_bit;
|
||||
uint8_t dec_bit;
|
||||
|
||||
for(i = 0; i < nitems; i++){
|
||||
/* Descramble the input bit */
|
||||
descr_bit = d_lfsr.next_bit_descramble(in[i]);
|
||||
|
||||
/* Perform NRZI decoding */
|
||||
dec_bit = (~((descr_bit - d_prev_bit_nrzi) % 2)) & 0x1;
|
||||
d_prev_bit_nrzi = descr_bit;
|
||||
|
||||
switch(d_state){
|
||||
case NO_SYNC:
|
||||
/* In AX.25 the LS bit is sent first */
|
||||
d_dec_b = (d_dec_b >> 1) | (dec_bit << 7);
|
||||
if(d_dec_b == AX25_SYNC_FLAG){
|
||||
enter_sync_state();
|
||||
}
|
||||
break;
|
||||
case IN_SYNC:
|
||||
/* In AX.25 the LS bit is sent first */
|
||||
d_dec_b = (d_dec_b >> 1) | (dec_bit << 7);
|
||||
|
||||
/*
|
||||
* If the received byte was an AX.25 sync flag, there are two
|
||||
* possibilities. Either it was the end of frame or just a repeat of the
|
||||
* preamble.
|
||||
*
|
||||
* Also in case in error at the preamble, the G3RUH polynomial should
|
||||
* re-sync after 3 repetitions of the SYNC flag. For this reason we demand
|
||||
* that the distance between the last SYNC flag is greater than 3 bytes
|
||||
*/
|
||||
if (d_dec_b == AX25_SYNC_FLAG) {
|
||||
if(d_received_bytes < 3) {
|
||||
enter_sync_state ();
|
||||
}
|
||||
else{
|
||||
/* Frame end */
|
||||
enter_frame_end();
|
||||
}
|
||||
}
|
||||
else if((d_dec_b & 0xfc) == 0x7c){
|
||||
/*This was a stuffed bit */
|
||||
d_dec_b <<= 1;
|
||||
}
|
||||
else if((d_dec_b & 0xfe) == 0xfe){
|
||||
/*This can never happen... Error! */
|
||||
if (d_received_bytes > AX25_MIN_ADDR_LEN) {
|
||||
message_port_pub (
|
||||
pmt::mp ("failed_pdu"),
|
||||
pmt::make_blob (d_frame_buffer, d_received_bytes));
|
||||
}
|
||||
reset_state();
|
||||
}
|
||||
else{
|
||||
d_decoded_bits++;
|
||||
if(d_decoded_bits == 8){
|
||||
d_frame_buffer[d_received_bytes++] = d_dec_b;
|
||||
d_decoded_bits = 0;
|
||||
|
||||
/*Check if the frame limit was reached */
|
||||
if(d_received_bytes >= d_max_frame_len) {
|
||||
message_port_pub (
|
||||
pmt::mp ("failed_pdu"),
|
||||
pmt::make_blob (d_frame_buffer, d_max_frame_len));
|
||||
reset_state();
|
||||
}
|
||||
}
|
||||
}
|
||||
break;
|
||||
case FRAME_END:
|
||||
d_dec_b = (d_dec_b >> 1) | (dec_bit << 7);
|
||||
if (d_dec_b == AX25_SYNC_FLAG) {
|
||||
d_dec_b = 0;
|
||||
d_decoded_bits = 0;
|
||||
d_received_bytes = 0;
|
||||
d_state = FRAME_END;
|
||||
}
|
||||
else{
|
||||
d_decoded_bits++;
|
||||
if(d_decoded_bits == 8){
|
||||
d_received_bytes++;
|
||||
if(d_received_bytes > 0){
|
||||
reset_state();
|
||||
}
|
||||
}
|
||||
}
|
||||
break;
|
||||
default:
|
||||
LOG_ERROR("Invalid decoding state");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
void
|
||||
ax25_decoder_bm_impl::decode (const uint8_t* in, size_t nitems)
|
||||
{
|
||||
size_t i;
|
||||
uint8_t dec_bit;
|
||||
|
||||
for (i = 0; i < nitems; i++) {
|
||||
|
||||
/* Perform NRZI decoding */
|
||||
dec_bit = (~(((in[i] & 0x1) - d_prev_bit_nrzi) % 2)) & 0x1;
|
||||
d_prev_bit_nrzi = in[i] & 0x1;
|
||||
|
||||
switch (d_state)
|
||||
{
|
||||
case NO_SYNC:
|
||||
/* In AX.25 the LS bit is sent first */
|
||||
d_dec_b = (d_dec_b >> 1) | (dec_bit << 7);
|
||||
if (d_dec_b == AX25_SYNC_FLAG) {
|
||||
enter_sync_state ();
|
||||
}
|
||||
break;
|
||||
case IN_SYNC:
|
||||
/* In AX.25 the LS bit is sent first */
|
||||
d_dec_b = (d_dec_b >> 1) | (dec_bit << 7);
|
||||
|
||||
/*
|
||||
* If the received byte was an AX.25 sync flag, there are two
|
||||
* possibilities. Either it was the end of frame or just a repeat of the
|
||||
* preamble.
|
||||
*
|
||||
* Also in case in error at the preamble, the G3RUH polynomial should
|
||||
* re-sync after 3 repetitions of the SYNC flag. For this reason we demand
|
||||
* that the distance between the last SYNC flag is greater than 3 bytes
|
||||
*/
|
||||
if (d_dec_b == AX25_SYNC_FLAG) {
|
||||
if (d_received_bytes < 2) {
|
||||
enter_sync_state ();
|
||||
}
|
||||
else {
|
||||
/* Frame end */
|
||||
enter_frame_end ();
|
||||
}
|
||||
}
|
||||
else if ((d_dec_b & 0xfc) == 0x7c) {
|
||||
/*This was a stuffed bit */
|
||||
d_dec_b <<= 1;
|
||||
}
|
||||
else if ((d_dec_b & 0xfe) == 0xfe) {
|
||||
/*This can never happen... Error! */
|
||||
if (d_received_bytes > AX25_MIN_ADDR_LEN) {
|
||||
message_port_pub (
|
||||
pmt::mp ("failed_pdu"),
|
||||
pmt::make_blob (d_frame_buffer, d_received_bytes));
|
||||
}
|
||||
reset_state ();
|
||||
}
|
||||
else {
|
||||
d_decoded_bits++;
|
||||
if (d_decoded_bits == 8) {
|
||||
d_frame_buffer[d_received_bytes++] = d_dec_b;
|
||||
d_decoded_bits = 0;
|
||||
|
||||
/*Check if the frame limit was reached */
|
||||
if (d_received_bytes >= d_max_frame_len) {
|
||||
message_port_pub (
|
||||
pmt::mp ("failed_pdu"),
|
||||
pmt::make_blob (d_frame_buffer, d_max_frame_len));
|
||||
reset_state ();
|
||||
}
|
||||
}
|
||||
}
|
||||
break;
|
||||
case FRAME_END:
|
||||
d_dec_b = (d_dec_b >> 1) | (dec_bit << 7);
|
||||
if (d_dec_b == AX25_SYNC_FLAG) {
|
||||
d_dec_b = 0;
|
||||
d_decoded_bits = 0;
|
||||
d_received_bytes = 0;
|
||||
d_state = FRAME_END;
|
||||
}
|
||||
else {
|
||||
d_decoded_bits++;
|
||||
if (d_decoded_bits == 8) {
|
||||
d_received_bytes++;
|
||||
if (d_received_bytes > 3) {
|
||||
reset_state ();
|
||||
}
|
||||
}
|
||||
}
|
||||
break;
|
||||
default:
|
||||
LOG_ERROR("Invalid decoding state");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Our virtual destructor.
|
||||
*/
|
||||
ax25_decoder_bm_impl::~ax25_decoder_bm_impl ()
|
||||
{
|
||||
delete [] d_frame_buffer;
|
||||
}
|
||||
|
||||
void
|
||||
ax25_decoder_bm_impl::reset_state ()
|
||||
{
|
||||
d_state = NO_SYNC;
|
||||
d_dec_b = 0;
|
||||
d_decoded_bits = 0;
|
||||
d_received_bytes = 0;
|
||||
d_prev_bit_nrzi = 0;
|
||||
}
|
||||
|
||||
void
|
||||
ax25_decoder_bm_impl::enter_sync_state ()
|
||||
{
|
||||
d_state = IN_SYNC;
|
||||
d_dec_b = 0;
|
||||
d_decoded_bits = 0;
|
||||
d_received_bytes = 0;
|
||||
}
|
||||
|
||||
void
|
||||
ax25_decoder_bm_impl::enter_frame_end ()
|
||||
{
|
||||
uint16_t fcs;
|
||||
uint16_t recv_fcs = 0x0;
|
||||
|
||||
/* First check if the size of the frame is valid */
|
||||
if (d_received_bytes < AX25_MIN_ADDR_LEN + sizeof(uint16_t)) {
|
||||
message_port_pub (pmt::mp ("failed_pdu"),
|
||||
pmt::make_blob (d_frame_buffer, d_received_bytes));
|
||||
d_dec_b = 0;
|
||||
d_decoded_bits = 0;
|
||||
d_received_bytes = 0;
|
||||
d_state = FRAME_END;
|
||||
return;
|
||||
}
|
||||
|
||||
/* Check if the frame is correct using the FCS field */
|
||||
fcs = ax25_fcs (d_frame_buffer, d_received_bytes - sizeof(uint16_t));
|
||||
recv_fcs = (((uint16_t) d_frame_buffer[d_received_bytes - 1]) << 8)
|
||||
| d_frame_buffer[d_received_bytes - 2];
|
||||
|
||||
if (fcs == recv_fcs) {
|
||||
/*
|
||||
* FIXME: Skip the right amount of header bytes based on the frame type
|
||||
*/
|
||||
message_port_pub (
|
||||
pmt::mp ("pdu"),
|
||||
pmt::make_blob (d_frame_buffer + AX25_MIN_ADDR_LEN + 2,
|
||||
d_received_bytes - AX25_MIN_ADDR_LEN - 2 - sizeof(uint16_t)));
|
||||
}
|
||||
else {
|
||||
message_port_pub (
|
||||
pmt::mp ("failed_pdu"),
|
||||
pmt::make_blob (d_frame_buffer,
|
||||
d_received_bytes - sizeof(uint16_t)));
|
||||
}
|
||||
d_dec_b = 0;
|
||||
d_decoded_bits = 0;
|
||||
d_received_bytes = 0;
|
||||
d_state = FRAME_END;
|
||||
}
|
||||
|
||||
|
||||
int
|
||||
ax25_decoder_bm_impl::work (int noutput_items,
|
||||
gr_vector_const_void_star &input_items,
|
||||
gr_vector_void_star &output_items)
|
||||
{
|
||||
const uint8_t *in = (const uint8_t *) input_items[0];
|
||||
|
||||
if(d_descramble){
|
||||
descramble_and_decode(in, noutput_items);
|
||||
}
|
||||
else{
|
||||
decode(in, noutput_items);
|
||||
}
|
||||
return noutput_items;
|
||||
}
|
||||
|
||||
} /* namespace satnogs */
|
||||
} /* namespace gr */
|
||||
|
|
@ -18,23 +18,23 @@
|
|||
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
*/
|
||||
|
||||
#ifndef INCLUDED_SATNOGS_AX25_DECODER_B_IMPL_H
|
||||
#define INCLUDED_SATNOGS_AX25_DECODER_B_IMPL_H
|
||||
#ifndef INCLUDED_SATNOGS_AX25_DECODER_BM_IMPL_H
|
||||
#define INCLUDED_SATNOGS_AX25_DECODER_BM_IMPL_H
|
||||
|
||||
#include <satnogs/ax25_decoder_b.h>
|
||||
#include <satnogs/ax25.h>
|
||||
#include <satnogs/ax25_decoder_bm.h>
|
||||
#include <gnuradio/digital/lfsr.h>
|
||||
|
||||
namespace gr
|
||||
{
|
||||
namespace satnogs
|
||||
{
|
||||
|
||||
class ax25_decoder_b_impl : public ax25_decoder_b
|
||||
class ax25_decoder_bm_impl : public ax25_decoder_bm
|
||||
{
|
||||
private:
|
||||
typedef enum {
|
||||
NO_SYNC,
|
||||
IN_SYNC
|
||||
typedef enum
|
||||
{
|
||||
NO_SYNC, IN_SYNC, FRAME_END
|
||||
} decoding_state_t;
|
||||
|
||||
/**
|
||||
|
@ -42,22 +42,32 @@ namespace gr
|
|||
* forwards all successfully decoded frames
|
||||
*/
|
||||
const bool d_promisc;
|
||||
const bool d_descramble;
|
||||
const size_t d_max_frame_len;
|
||||
decoding_state_t d_state;
|
||||
uint8_t d_dec_b;
|
||||
uint8_t d_prev_bit;
|
||||
uint8_t d_prev_bit_nrzi;
|
||||
size_t d_received_bytes;
|
||||
size_t d_decoded_bits;
|
||||
size_t d_cont_1;
|
||||
|
||||
digital::lfsr d_lfsr;
|
||||
uint8_t *d_frame_buffer;
|
||||
|
||||
void reset_state();
|
||||
void enter_sync_state();
|
||||
void update_recv_frame(uint8_t byte);
|
||||
void
|
||||
reset_state ();
|
||||
void
|
||||
enter_sync_state ();
|
||||
void
|
||||
enter_frame_end ();
|
||||
|
||||
void
|
||||
descramble_and_decode (const uint8_t *in, size_t nitems);
|
||||
void
|
||||
decode (const uint8_t *in, size_t nitems);
|
||||
|
||||
public:
|
||||
ax25_decoder_b_impl (std::string addr, uint8_t ssid, bool promisc);
|
||||
~ax25_decoder_b_impl ();
|
||||
ax25_decoder_bm_impl (const std::string& addr, uint8_t ssid, bool promisc,
|
||||
bool descramble, size_t max_frame_len);
|
||||
~ax25_decoder_bm_impl ();
|
||||
|
||||
// Where all the action really happens
|
||||
int
|
||||
|
@ -68,5 +78,5 @@ namespace gr
|
|||
} // namespace satnogs
|
||||
} // namespace gr
|
||||
|
||||
#endif /* INCLUDED_SATNOGS_AX25_DECODER_B_IMPL_H */
|
||||
#endif /* INCLUDED_SATNOGS_AX25_DECODER_BM_IMPL_H */
|
||||
|
|
@ -45,8 +45,10 @@ namespace gr
|
|||
digital::lfsr d_lfsr;
|
||||
boost::mutex d_mutex;
|
||||
|
||||
void add_sob(uint64_t item);
|
||||
void add_eob(uint64_t item);
|
||||
void
|
||||
add_sob (uint64_t item);
|
||||
void
|
||||
add_eob (uint64_t item);
|
||||
|
||||
public:
|
||||
ax25_encoder_mb_impl (const std::string& dest_addr, uint8_t dest_ssid,
|
||||
|
|
|
@ -16,7 +16,6 @@
|
|||
#include "satnogs/multi_format_msg_sink.h"
|
||||
#include "satnogs/cw_to_symbol.h"
|
||||
#include "satnogs/sine_matched_filter_ff.h"
|
||||
#include "satnogs/ax25_decoder_b.h"
|
||||
#include "satnogs/udp_msg_source.h"
|
||||
#include "satnogs/debug_msg_source.h"
|
||||
#include "satnogs/tcp_rigctl_msg_source.h"
|
||||
|
@ -30,6 +29,7 @@
|
|||
#include "satnogs/coarse_doppler_correction_cc.h"
|
||||
#include "satnogs/debug_msg_source_raw.h"
|
||||
#include "satnogs/ax25_encoder_mb.h"
|
||||
#include "satnogs/ax25_decoder_bm.h"
|
||||
%}
|
||||
|
||||
|
||||
|
@ -48,8 +48,6 @@ GR_SWIG_BLOCK_MAGIC2(satnogs, cw_to_symbol);
|
|||
%include "satnogs/sine_matched_filter_ff.h"
|
||||
GR_SWIG_BLOCK_MAGIC2(satnogs, sine_matched_filter_ff);
|
||||
|
||||
%include "satnogs/ax25_decoder_b.h"
|
||||
GR_SWIG_BLOCK_MAGIC2(satnogs, ax25_decoder_b);
|
||||
%include "satnogs/udp_msg_source.h"
|
||||
GR_SWIG_BLOCK_MAGIC2(satnogs, udp_msg_source);
|
||||
%include "satnogs/debug_msg_source.h"
|
||||
|
@ -75,3 +73,5 @@ GR_SWIG_BLOCK_MAGIC2(satnogs, coarse_doppler_correction_cc);
|
|||
GR_SWIG_BLOCK_MAGIC2(satnogs, debug_msg_source_raw);
|
||||
%include "satnogs/ax25_encoder_mb.h"
|
||||
GR_SWIG_BLOCK_MAGIC2(satnogs, ax25_encoder_mb);
|
||||
%include "satnogs/ax25_decoder_bm.h"
|
||||
GR_SWIG_BLOCK_MAGIC2(satnogs, ax25_decoder_bm);
|
||||
|
|
Loading…
Reference in New Issue