2009-02-13 11:33:42     CAN bus timing with 5282

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2009-02-13 11:33:42     CAN bus timing with 5282

Tom Wimmer (GERMANY)

Message: 69421   


Hello all,


I try to read Can messages from two CAN nodes communicating at 19.2 kbit/s.


To find possible bit timings i used Miquel`s excel sheets and code, from there:




Thanks a lot for that Miquel!




The hardware is a devkit from ssv with the dnp/5282 stamp. I use this programme versions:


(as i considered them as stable)


kernel module: can4linux-3.2-SSV20051024


toolchain: m68k-elf-tools-20030314


compiler: gcc version 4.3.2




the receive sample from "can4linux-examples-3.5.3" gives only one msg:


# ./receive /tmp/dev/can0

Received with ret=1:    943936724.079156 id=-1/0xffffffff

        len=0 flags=0x10 : sD : msg=


This msg - and only this one - is also brought from my test programme cansniff and every other


read/receive code i found.


When the dev is reading, the CAN status changes: 0 to 128 to 256 to 384 to 400.


When i try to send something, only the first msg is sent out (says the oscilloscope)


and the other fill the tx buffer until its full.




As i estimated a timing problem, i tried various settings to see in cansniff.c.




Any idea?







2009-02-13 12:17:42     Re: CAN bus timing with 5282

Mike Frysinger (UNITED STATES)

Message: 69423   


this is a site for Blackfin processors.  if you arent using a Blackfin part, please seek help elsewhere.