2016-01-15 21:35 GMT+01:00 Guy Harris <g...@alum.mit.edu>: > > On Jan 15, 2016, at 10:44 AM, Guenter Ebermann > <guenter.eberm...@googlemail.com> wrote: > > I don't know whether Hannes still works at X2E. You might want to try > sending an e-mail to him asking whether a format for DLT_FLEXRAY was ever > defined - and, if it has, asking him to send me a copy so that I can add it > to the link-layer header types page: > > http://www.tcpdump.org/linktypes.html > > (and, if any of the *others* were defined, to send those to me as well). > > If mail to him bounces, you could try contacting X2E to see if that > information is available, or if they ever supporting writing out files in > pcap or pcapng format. > > If they never wrote files out with a link-layer header type of 210 for > DLT_FLEXRAY/LINKTYPE_FLEXRAY, then you can use it for your own purposes - > send us the spec and I'll add it to the link-layer header types page. > > If they did, but they don't tell you what format they use, we can create a > new LINKTYPE_/DLT_ value for your format, and provide a public specification > for that one.
I asked Hannes about DLT_FLEXRAY. He told me that they currently dont use pcap for FlexRay and have only used it in a limited scenario and that we are free to change the layout. The format represented the bitsream from the bus 1:1 without an additional header. The only deviation was the padding: the data was padded to align to 4 byte boundaries. This is my suggestion for an extension: I want to extend the frame by a "measurement-header": This header is added by the measurement device. It contains one bit for the FlexRay channel (A or B), a "data-type" enumeration and error-flags. Error-flags will be all kind of decoding errors which may be detected during capture of a FlexRay frame. That is: TSS, FSS, BSS, or FES violations. Header CRC or Frame CRC errors and all kind of "short-item-counts" that is, if not all bytes of the frame-bitstream could be captured. One enum-value of the "data-type" will be for a "data-frame", whereas a data frame would have exactly the same coding as on the FlexRay bus. The second enum-value of the "data-type" will be a "flexray-symbol", which contains the bitlength information of the captured FlexRay symbol (used for CAS and Wakeup). BR Günter _______________________________________________ tcpdump-workers mailing list tcpdump-workers@lists.tcpdump.org https://lists.sandelman.ca/mailman/listinfo/tcpdump-workers
