> I tried to locate the simple framer, but not able to find it. Greping for it > takes me to the c code of gr_simple_framer but I am not able to make much > sense of it. Can you please elaborate a bit more...? Where does the > correlations takes place within the python code.
The framer sink is a block implemented in C, which is why there is no python code for it, the actual correlating happens in gr_correlate_access_code (also implemented in C), they are connected together to do the demodulating in pkt.py, which is modulation independent. (from: http://gnuradio.org/trac/browser/gnuradio/trunk/gnuradio-core/src/python/gnuradio/blks2impl/pkt.py) 141 self.correlator = gr.correlate_access_code_bb(access_code, threshold) 142 143 self.framer_sink = gr.framer_sink_1(self._rcvd_pktq) 144 self.connect(self, self._demodulator, self.correlator, self.framer_sink) correlate_access_code takes a stream of bits from the demodulator and tries to find the code prepended to each packet, when it does it sets the second LSB (because each demodulated bit is in the LSB and the other 7 are 0). The framer_sink_1 watches for this flag and blindly collects the packet starting from that point. If you want to get a better idea of what's happening and understand C you can look here: http://gnuradio.org/trac/browser/gnuradio/trunk/gnuradio-core/src/lib/general/gr_correlate_access_code_bb.cc http://gnuradio.org/trac/browser/gnuradio/trunk/gnuradio-core/src/lib/general/gr_framer_sink_1.cc (Note that if you have an old version of the trunk checked out you might be better off looking at those files in your local repository) Jason _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
