Re: CAN libpcap capture endianess

[Marc Kleine-Budde <mkl@pengutronix.de>]

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On 09/11/2013 08:30 PM, Ico Doornekamp wrote:
> Since CAN does not have a way to distinguish between sub-protocols, wireshark
> has no way to detect the payload as CANopen.  To force wireshark to use the
> CANopen dissector, you can change the next level protocol in the preferences
> window, as described here:

Correct.

> https://libbits.wordpress.com/2012/05/07/capturing-and-analyzing-can-frames-with-wireshark/

I see, thanks.

>> But you're using a 64 bit system while Yegor uses a 32 bit one
>> (according to your notes below).
> 
> Indeed, but I believe that should in no way interfere with captured data
> endianess.
> 
>> Your dump doesn't look correct in my wireshark, it has alternating
>> extended and standard frames and the standard frames have identifiers
>> of 0x060000 which is not valid.
>>
>> Does the command line tool candump show proper frames?
> 
> I'll have to look into that tomorrow, at this time I only have access to
> the capture file I made earlier.

What kind of CAN hardware are you using? Maybe it's not compatible with
the existing driver.

> For the record: my capture was made with the following commands:
> 
> slcan_attach /dev/ttyUSB0 -o -s 5
> slcand ttyUSB0
> ifconfig slcan0 up
> wireshark -i slcan0 -w capture.pcap

I've never used a slcan device, but looks good, there aren't that many
options.

Marc
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