Dan Halperin wrote: > Is the CRC actually required? In the version of the code I'm using on > the lab machines (which is from early January), the framer_sink only > uses the length field to form the packet and the CRC is checked later. > We actually do the CRC after doing some ECC on the bits themselves.
The CRC only applies to the actual data payload; it gets appended at the end. But the len field that gets put (twice) into the header is the length of the payload + CRC. On receive, if the len field is corrupt, the received packet will fail CRC, because the last four bytes of the payload will be some arbitrary value, not the actual CRC field (and the packet won't have the right contents anyway.) So no strong protection is really needed for the len field. -- Johnathan Corgan Corgan Enterprises LLC http://corganenterprises.com _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
