>-----Original Message----- >From: Wolfgang Grandegger [mailto:[email protected]] >Sent: Friday, September 04, 2009 8:11 PM >To: Gole, Anant >Cc: [email protected]; Marc Kleine-Budde >Subject: Re: [PATCH V2] net-next-2.6:can: add TI CAN (HECC) driver > [snip] > expected: 0078: [8] 16 17 18 19 1a 1b 1c 1d >> received: 0078: [8] 18 19 1a 1b 1c 1d 1e 1f >> >> I am losing packets in send probably ... > >You could attach another board to the bus sniffing the traffic with >candump. This should make obvious what happened. > >Wolfgang. >
Yes I did that by putting a 3rd can sniffer node and have some interesting observations: 1. First I picked up the two canecho utilities from Vladislav that he modified from Marc's git (Thanks to both of you) https://lists.berlios.de/pipermail/socketcan-core/2009-August/002871.html 2. I noticed that the write functions on both did not check for errors and suspected that that might be the issue of not having enough buffers on the queue and it was - After changing the write call to loop until successful I was able to get traffic moving (until later when it fails again) - the change was a single line on write calls (in both utilities) while (write(s, &tx_frames[send_pos], sizeof(*tx_frames)) < 0) ; 3. On further testing I found that at times the canecho_gen node generates a duplicate frame (probably my driver is at fault here) and hence the utility fails after a few seconds. The duplicate frame was verified on the 3rd node on the bus (the scanner). Any clues welcome. I will continue by debug. Regards, Anatn _______________________________________________ Socketcan-core mailing list [email protected] https://lists.berlios.de/mailman/listinfo/socketcan-core
