Hi Filip, the structure of serial AM packets is explained here: http://docs.tinyos.net/tinywiki/index.php/Mote-PC_serial_communication_and_SerialForwarder#BaseStation_and_net.tinyos.tools.Listen About the last byte: check once more that you pass the correct payload length, because in the example it seems that msg len field is 3 (not 4).
Jan On Tue, Feb 5, 2013 at 3:05 PM, Filip Jurnečka <[email protected]> wrote: > Ok, I did that. I know the byte 80 is in fact my defined AM type. Now it > is still an open question for me why does the CBC-MAC override the last > byte in the packet? > > Best, > Filip Jurnecka > > On Tue, 05 Feb 2013 14:58:18 +0100, wasif masood <[email protected]> > wrote: > >> Checkout the CC2420 datasheet for details regarding the 802.15.4 header >> strucutre. >> >> On Tue, Feb 5, 2013 at 2:17 PM, Filip Jurnečka >> <[email protected]>wrote: >> >>> Hi there. >>> >>> I wonder how the packet delimiters work. Say I have two packets. If sent >>> normally, the BS app displays them as: >>> 00 FF FF 00 01 00 22 80 >>> 00 FF FF 00 01 01 22 80 00 >>> >>> Now I don't know what the first 00 is, but the next FFFF is the >>> broadcast >>> address, the 0001 should be my address, the next 00/01 defines the >>> length >>> of the packet data. What is the 22? What is the 80? Is it the delimiter >>> of >>> the data to follow? Obviously, the last 00 is the data sent. >>> >>> Now it gets more interesting, if I enable the in-line CBC-MAC with 4 >>> bytes >>> output, I get the following. >>> 00 FF FF 00 01 03 22 B7 E2 4C FB >>> 00 FF FF 00 01 04 22 80 71 36 57 EE >>> >>> The question is mainly about the fact that the output is overriding the >>> last byte of the unauthenticated message, i.e. the delimiter or the >>> payload byte. Any ideas why and how to fix it? >>> >>> Best regards, >>> Filip Jurnecka >>> _______________________________________________ >>> Tinyos-help mailing list >>> [email protected] >>> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >>> >> >> > > _______________________________________________ > Tinyos-help mailing list > [email protected] > https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
