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

Document created by Aaronwu Employee on Aug 13, 2013
Version 1Show Document
  • View in full screen mode

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:

 

http://blackfin.uclinux.org/gf/project/uclinux-dist/forum/?action=ForumBrowse&forum_id=39&_forum_action=ForumMessageBrowse&thread_id=17924

 

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?

 

receive.c

cansniff.c

QuoteReplyEditDelete

 

 

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.

Attachments

Outcomes