diff --git a/README.txt b/README.txt index 45b983b..4ee25f1 100644 --- a/README.txt +++ b/README.txt @@ -1 +1,92 @@ -hi +Hi! + +This is a collection of custom blocks that are not directly associated with a +special project. For sample applications see: + +https://github.com/bastibl/gr-ieee802-11 +https://github.com/bastibl/gr-ieee802-15-4 + + + +### Wireshark Connector + +This blocks outputs PDUs in the PCAP format. The resulting file can be opened in +nearly all network monitoring applications. Some examples are Wireshark, Tshark, +and tcpdump. Currently, it support WiFi packets with radiotap header and ZigBee. + +Since GNU Radio does not support File Sinks that append to a file, one can not +open Linux pipes / fifos. For that reason, it is not easily possible to monitor +traffic live. However, loading the file in Wireshark works. + +I made a patch that adds an append option to the File Sink. If you are +interested see: +https://github.com/bastibl/gnuradio/commit/befa5bd94b59a56e13d7ec4fe0da86637fe624d9 + +For further information about radiotap, pcap, and Wireshark see: +http://www.radiotap.org/ +http://www.wireshark.org/ + + + +### Burst Tagger + +Tags a burst / packet with tx_sob und tx_eob tags. This is useful if the SDR is +operating in half duplex mode. With adding a tx_eob the USRP switches back to +receive mode immediately. That way, direct responses like ACKs are not missed. + +The block searches for a special tag that indicates the start of a burst. The +name of this tag is configurable. The tag should indicate the length of the +packet in samples. Also a multiplier can be specified, which multiples the +length given in the tag. + + + +### Packet Dropper + +Drops a configurable percentage of messages. I used it to test protocol logic +like ACKs, retransmission and stuff. + + + +### Packet Pad + +Adds a configurable number of zeros before and after a burst. The burst has to +be started with an tx_sob, and ended with a tx_eob tag. +From time to time I had issues when I did not pad the sample stream. This block +helps to investigate that. +Also it is handy for loopback testing when there is no continues sample stream. + + + +### Periodic Msg Source + +This block sends messages at regular intervals much like the message strobe block in +mainline GNU Radio. With this block you can in addition configure the number of +packets that are sent. When all normal messages are sent, the blocks sends a final +PMT_EOF message to indicate that it is done. + +I used this block for performance tests with no-GUI flow graphs. This way it is +possible to shout down no-GUI flow graphs with message blocks. As far as I know, +this is not possible with mainline GNU Radio. For that reason, I created a patch +that checks if the block is done after a message was handled. See + +https://github.com/bastibl/gnuradio/commit/75a22cb8c10d867a68c8849bf56a0aa3906df266 + + + +### Dependencies + +GNU Radio v3.7 + + +### Installation + +git clone https://github.com/bastibl/gr-foo.git +cd gr-foo +mkdir build +cd build +cmake .. +make +sudo make install +sudo ldconfig +