[Ovmsdev] MCP2515 driver bug?

Michael Balzer dexter at expeedo.de
Thu Jun 3 15:07:41 HKT 2021


Mark,

I'd give the bit timing a try first, the MCP2515 seems to be very 
sensitive for this. I've even had some trouble finding a working 
configuration for the 50 kbit timing I've added a couple weeks ago.

We currently use 00 / D0 / 82 which is also the result of the old 
Intrepid timing calculator. That's a propagation segment of 1 Tq and 3 
Tq per phase, resulting in samling between 50% - 62.5%.

The Arduino MCP CAN lib by Cory Fowler also had this previously, but 
then changed in…

https://github.com/coryjfowler/MCP_CAN_lib/commit/ece730cf697fef1cbe8a90111694868168d41000

…to 00 / CA / 81, which is a propagation segment of 3 Tq and 2 Tq 
per 
phase, shifting the sampling window to 62.5 - 75%.

Our current configuration scheme for the internal SJA1000 compatible CAN 
seems to sample at 62.5 - 75% as well, so that would also match.

Regards,
Michael


Am 03.06.21 um 07:36 schrieb Mark Webb-Johnson:
>
> I’m working on an implementation of IP stack over CAN for the Tesla 
> Roadster. IP frames are encoded as a length followed by a sequence of 
> CAN frames, all on the same ID. This runs over a 1MHz bus, so 
> presumably the traffic volume could be high at times.
>
> I was having problems with this running on CAN2, so tried CAN1 and it 
> worked perfectly. Here are some simple dumps of a single PING packet 
> (and single PING response packet):
>
> ID #111 is used to transmit an IP packet, and ID #110 is used to 
> receive an IP packet. The special empty data frame is an acknowledgment.
>
> Using latest master branch code (3.2.016-196-g0aad1a9f/ota_1/edge 
> (build idf v3.3.4-848-g1ff5e24b1 Jun  2 2021 09:28:58)).
>
> So, first let’s test with traffic on CAN1 (active, 1Mbps), and 
> listening on CAN2 (listen, 1Mbps):
>
>         TCPDUMP:
>
>
>             05:57:55.980291 IP (tos 0x0, ttl 64, id 43101, offset 0,
>             flags [DF], proto ICMP (1), length 84)
>
>                 10.10.99.3 > 10.10.99.2: ICMP echo request, id 23372,
>             seq 1, length 64
>
>             0x0000:  4500 0054 a85d 4000 4001 b832 0a0a 6303
>              E..T.]@. at ..2..c.
>
>             0x0010:  0a0a 6302 0800 7df8 5b4c 0001 5361 b860
>              ..c...}.[L..Sa.`
>
>             0x0020:  19f5 0e00 0809 0a0b 0c0d 0e0f 1011 1213
>              ................
>
>             0x0030:  1415 1617 1819 1a1b 1c1d 1e1f 2021 2223
>              .............!"#
>
>             0x0040:  2425 2627 2829 2a2b 2c2d 2e2f 3031 3233
>              $%&'()*+,-./0123
>
>             0x0050:  3435 3637                                4567
>
>
>             05:57:56.436190 IP (tos 0x0, ttl 64, id 14937, offset 0,
>             flags [none], proto ICMP (1), length 84)
>
>                 10.10.99.2 > 10.10.99.3: ICMP echo reply, id 23372,
>             seq 1, length 64
>
>             0x0000:  4500 0054 3a59 0000 4001 6637 0a0a 6302
>              E..T:Y.. at .f7..c.
>
>             0x0010:  0a0a 6303 0000 85f8 5b4c 0001 5361 b860
>              ..c.....[L..Sa.`
>
>             0x0020:  19f5 0e00 0809 0a0b 0c0d 0e0f 1011 1213
>              ................
>
>             0x0030:  1415 1617 1819 1a1b 1c1d 1e1f 2021 2223
>              .............!"#
>
>             0x0040:  2425 2627 2829 2a2b 2c2d 2e2f 3031 3233
>              $%&'()*+,-./0123
>
>             0x0050:  3435 3637                                4567
>
>
>         Traffic (as shown on PC the other end of the can log tcp
>         connection):
>
>
>             tx: #111 54 00
>
>             tx: #111 45 00 00 54 a8 5d 40 00
>
>             tx: #111 40 01 b8 32 0a 0a 63 03
>
>             tx: #111 0a 0a 63 02 08 00 7d f8
>
>             tx: #111 5b 4c 00 01 53 61 b8 60
>
>             tx: #111 19 f5 0e 00 08 09 0a 0b
>
>             tx: #111 0c 0d 0e 0f 10 11 12 13
>
>             tx: #111 14 15 16 17 18 19 1a 1b
>
>             tx: #111 1c 1d 1e 1f 20 21 22 23
>
>             tx: #111 24 25 26 27 28 29 2a 2b
>
>             tx: #111 2c 2d 2e 2f 30 31 32 33
>
>             tx: #111 34 35 36 37
>
>
>             rx: #110
>
>             rx: #110 54 00
>
>             rx: #110 45 00 00 54 3a 59 00 00
>
>             rx: #110 40 01 66 37 0a 0a 63 02
>
>             rx: #110 0a 0a 63 03 00 00 85 f8
>
>             rx: #110 5b 4c 00 01 53 61 b8 60
>
>             rx: #110 19 f5 0e 00 08 09 0a 0b
>
>             rx: #110 0c 0d 0e 0f 10 11 12 13
>
>             rx: #110 14 15 16 17 18 19 1a 1b
>
>             rx: #110 1c 1d 1e 1f 20 21 22 23
>
>             rx: #110 24 25 26 27 28 29 2a 2b
>
>             rx: #110 2c 2d 2e 2f 30 31 32 33
>
>             rx: #110 34 35 36 37
>
>
>         CAN1 active:
>
>
>             1T11 111 54 00
>
>             1R11 110
>
>
>             1CER TX_Queue T11 111 40 01 b8 32 0a 0a 63 03
>
>             1T11 111 45 00 00 54 a8 5d 40 00
>
>             1T11 111 40 01 b8 32 0a 0a 63 03
>
>             1CER TX_Queue T11 111 5b 4c 00 01 53 61 b8 60
>
>             1T11 111 0a 0a 63 02 08 00 7d f8
>
>             1T11 111 5b 4c 00 01 53 61 b8 60
>
>             1CER TX_Queue T11 111 0c 0d 0e 0f 10 11 12 13
>
>             1T11 111 19 f5 0e 00 08 09 0a 0b
>
>             1T11 111 0c 0d 0e 0f 10 11 12 13
>
>             1CER TX_Queue T11 111 1c 1d 1e 1f 20 21 22 23
>
>             1T11 111 14 15 16 17 18 19 1a 1b
>
>             1T11 111 1c 1d 1e 1f 20 21 22 23
>
>             1CER TX_Queue T11 111 2c 2d 2e 2f 30 31 32 33
>
>             1T11 111 24 25 26 27 28 29 2a 2b
>
>             1T11 111 2c 2d 2e 2f 30 31 32 33
>
>             1T11 111 34 35 36 37
>
>
>             1R11 110 54 00
>
>             1R11 110 45 00 00 54 3a 59 00 00
>
>             1R11 110 40 01 66 37 0a 0a 63 02
>
>             1R11 110 0a 0a 63 03 00 00 85 f8
>
>             1R11 110 5b 4c 00 01 53 61 b8 60
>
>             1R11 110 19 f5 0e 00 08 09 0a 0b
>
>             1R11 110 0c 0d 0e 0f 10 11 12 13
>
>             1R11 110 14 15 16 17 18 19 1a 1b
>
>             1R11 110 1c 1d 1e 1f 20 21 22 23
>
>             1R11 110 24 25 26 27 28 29 2a 2b
>
>             1R11 110 2c 2d 2e 2f 30 31 32 33
>
>             1R11 110 34 35 36 37
>
>
>         CAN2 listen:
>
>
>             2R11 111 54 00
>
>             2R11 110
>
>
>             2R11 111 45 00 00 54 a8 5d 40 00
>
>             2R11 111 40 01 b8 32 0a 0a 63 03
>
>             2R11 111 0a 0a 63 02 08 00 7d f8
>
>             2R11 111 5b 4c 00 01 53 61 b8 60
>
>             2R11 111 19 f5 0e 00 08 09 0a 0b
>
>             2R11 111 0c 0d 0e 0f 10 11 12 13
>
>             2R11 111 14 15 16 17 18 19 1a 1b
>
>             2R11 111 1c 1d 1e 1f 20 21 22 23
>
>             2R11 111 24 25 26 27 28 29 2a 2b
>
>             2R11 111 2c 2d 2e 2f 30 31 32 33
>
>             2R11 111 34 35 36 37
>
>
>             2R11 110 54 00
>
>             2CER Error intr=10 rxpkt=14 txpkt=0 errflags=0x23401c01
>             rxerr=0 txerr=0 rxinval=0 rxovr=0 txovr=0 txdelay=0
>             txfail=0 wdgreset=0 errreset=0
>
>             2R11 110 40 01 66 37 0a 0a 63 02
>
>             2R11 110 19 f5 0e 00 08 09 0a 0b
>
>             2R11 110 34 35 36 37
>
>             2R11 110 45 00 00 54 3a 59 00 00
>
>
> Conclusion is that the CAN1 traffic looks fine, and the PING packet 
> gets a good reply. All successful. But the CAN2 listen is missing a 
> few packets and the last packet is out of order.
>
> Now, let’s test with traffic on CAN2 (active, 1Mbps), and listening on 
> CAN1 (listen, 1Mbps):
>
>     TCPDUMP:
>
>         06:00:33.004060 IP (tos 0x0, ttl 64, id 58240, offset 0, flags
>         [DF], proto ICMP (1), length 84)
>
>             10.10.99.3 > 10.10.99.2: ICMP echo request, id 23393, seq
>         1, length 64
>
>         0x0000:  4500 0054 e380 4000 4001 7d0f 0a0a 6303  E..T.. at .@.}...c.
>
>         0x0010:  0a0a 6302 0800 7cc8 5b61 0001 f161 b860  ..c...|.[a...a.`
>
>         0x0020:  8b0f 0000 0809 0a0b 0c0d 0e0f 1011 1213  ................
>
>         0x0030:  1415 1617 1819 1a1b 1c1d 1e1f 2021 2223  .............!"#
>
>         0x0040:  2425 2627 2829 2a2b 2c2d 2e2f 3031 3233  $%&'()*+,-./0123
>
>         0x0050:  3435 3637             
                   4567
>
>
>     Traffic (as shown on PC the other end of the can log tcp connection):
>
>
>             tx: #111 54 00
>
>             tx: #111 45 00 00 54 e3 80 40 00
>
>             tx: #111 40 01 7d 0f 0a 0a 63 03
>
>             tx: #111 0a 0a 63 02 08 00 7c c8
>
>             tx: #111 5b 61 00 01 f1 61 b8 60
>
>             tx: #111 8b 0f 00 00 08 09 0a 0b
>
>             tx: #111 0c 0d 0e 0f 10 11 12 13
>
>             tx: #111 14 15 16 17 18 19 1a 1b
>
>             tx: #111 1c 1d 1e 1f 20 21 22 23
>
>             tx: #111 24 25 26 27 28 29 2a 2b
>
>             tx: #111 2c 2d 2e 2f 30 31 32 33
>
>             tx: #111 34 35 36 37
>
>
>             rx: #110
>
>             rx: #110 54 00
>
>             rx: #110 45 00 00 54 3a 5a 00 00
>
>             rx: #110 0a 0a 63 03 00 00 84 c8
>
>             rx: #110 8b 0f 00 00 08 09 0a 0b
>
>             rx: #110 34 35 36 37
>
>             rx: #110 40 01 66 36 0a 0a 63 02
>
>
>     CAN2 active:
>
>
>         2T11 111 54 00
>
>         2R11 110
>
>
>         2CER TX_Queue T11 111 40 01 7d 0f 0a 0a 63 03
>
>         2T11 111 45 00 00 54 e3 80 40 00
>
>         2T11 111 40 01 7d 0f 0a 0a 63 03
>
>         2CER TX_Queue T11 111 5b 61 00 01 f1 61 b8 60
>
>         2T11 111 0a 0a 63 02 08 00 7c c8
>
>         2T11 111 5b 61 00 01 f1 61 b8 60
>
>         2CER TX_Queue T11 111 0c 0d 0e 0f 10 11 12 13
>
>         2T11 111 8b 0f 00 00 08 09 0a 0b
>
>         2T11 111 0c 0d 0e 0f 10 11 12 13
>
>         2CER TX_Queue T11 111 1c 1d 1e 1f 20 21 22 23
>
>         2T11 111 14 15 16 17 18 19 1a 1b
>
>         2T11 111 1c 1d 1e 1f 20 21 22 23
>
>         2CER TX_Queue T11 111 2c 2d 2e 2f 30 31 32 33
>
>         2T11 111 24 25 26 27 28 29 2a 2b
>
>         2T11 111 2c 2d 2e 2f 30 31 32 33
>
>         2T11 111 34 35 36 37
>
>
>         2R11 110 54 00
>
>         2R11 110 45 00 00 54 3a 5a 00 00
>
>         2CER Error intr=15 rxpkt=3 txpkt=12 errflags=0x23401c01
>         rxerr=0 txerr=0 rxinval=0 rxovr=0 txovr=0 txdelay=5 
txfail=0
>         wdgreset=0 errreset=0
>
>         2R11 110 0a 0a 63 03 00 00 84 c8
>
>         2R11 110 8b 0f 00 00 08 09 0a 0b
>
>         2R11 110 34 35 36 37
>
>         2R11 110 40 01 66 36 0a 0a 63 02
>
>
>     CAN1 listen:
>
>
>         1R11 111 54 00
>         1R11 110
>
>
>         1R11 111 45 00 00 54 e3 80 40 00
>         1R11 111 40 01 7d 0f 0a 0a 63 03
>         1R11 111 0a 0a 63 02 08 00 7c c8
>         1R11 111 5b 61 00 01 f1 61 b8 60
>         1R11 111 8b 0f 00 00 08 09 0a 0b
>         1R11 111 0c 0d 0e 0f 10 11 12 13
>         1R11 111 14 15 16 17 18 19 1a 1b
>         1R11 111 1c 1d 1e 1f 20 21 22 23
>         1R11 111 24 25 26 27 28 29 2a 2b
>         1R11 111 2c 2d 2e 2f 30 31 32 33
>         1R11 111 34 35 36 37
>
>
>         1R11 110 54 00
>         1R11 110 45 00 00 54 3a 5a 00 00
>         1R11 110 40 01 66 36 0a 0a 63 02
>         1R11 110 0a 0a 63 03 00 00 84 c8
>         1R11 110 5b 61 00 01 f1 61 b8 60
>         1R11 110 8b 0f 00 00 08 09 0a 0b
>         1R11 110 0c 0d 0e 0f 10 11 12 13
>         1R11 110 14 15 16 17 18 19 1a 1b
>         1R11 110 1c 1d 1e 1f 20 21 22 23
>         1R11 110 24 25 26 27 28 29 2a 2b
>         1R11 110 2c 2d 2e 2f 30 31 32 33
>         1R11 110 34 35 36 37
>
>
> Conclusion is that the CAN2 transmit traffic looks fine, but no PING 
> reply received via CAN. The CAN1 listen shows the reply just fine.
>
> Here is that last CAN1 listen, with timestamps:
>
>     1622696433.080107 1R11 111 54 00
>     1622696433.081657 1R11 110
>
>     1622696433.227479 1R11 111 45 00 00 54 e3 80 40 00
>     1622696433.228318 1R11 111 40 01 7d 0f 0a 0a 63 03
>     1622696433.245727 1R11 111 0a 0a 63 02 08 00 7c c8
>     1622696433.246214 1R11 111 5b 61 00 01 f1 61 b8 60
>     1622696433.248219 1R11 111 8b 0f 00 00 08 09 0a 0b
>     1622696433.248772 1R11 111 0c 0d 0e 0f 10 11 12 13
>     1622696433.250774 1R11 111 14 15 16 17 18 19 1a 1b
>     1622696433.251338 1R11 111 1c 1d 1e 1f 20 21 22 23
>     1622696433.253380 1R11 111 24 25 26 27 28 29 2a 2b
>     1622696433.253944 1R11 111 2c 2d 2e 2f 30 31 32 33
>     1622696433.265937 1R11 111 34 35 36 37
>
>     1622696433.269221 1R11 110 54 00
>     1622696433.272095 1R11 110 45 00 00 54 3a 5a 00 00
>     1622696433.272125 1R11 110 40 01 66 36 0a 0a 63 02
>     1622696433.272156 1R11 110 0a 0a 63 03 00 00 84 c8
>     1622696433.272193 1R11 110 5b 61 00 01 f1 61 b8 60
>     1622696433.272245 1R11 110 8b 0f 00 00 08 09 0a 0b
>     1622696433.272277 1R11 110 0c 0d 0e 0f 10 11 12 13
>     1622696433.272314 1R11 110 14 15 16 17 18 19 1a 1b
>     1622696433.272354 1R11 110 1c 1d 1e 1f 20 21 22 23
>     1622696433.272387 1R11 110 24 25 26 27 28 29 2a 2b
>     1622696433.272420 1R11 110 2c 2d 2e 2f 30 31 32 33
>     1622696433.272452 1R11 110 34 35 36 37
>
>
> It is 1Mbps, with 30us or so between each packet. This is the *only* 
> traffic on the bus. Everything else is turned off. Roughly 12 packets 
> each way. Surely even if we were hitting a performance limit, our 
> buffers can handle 12 packets?
>
> The good news is that I have a good environment to replicate this 
> issue now, so any fix should be easy to test.
>
> I haven’t worked on the MCP2515 driver in our code in a long time, but 
> it certainly seems something is messed up and that could be badly 
> affecting vehicle modules using anything other than CAN1.
>
> I will start to look at this over the weekend, but has anyone got any 
> ideas/suggestions? Perhaps the bit timing registers are off by a small 
> amount (so it works on CAN1 but not on CAN2)? Or something more 
> serious in our driver?
>
> Regards, Mark.
>
>
> _______________________________________________
> OvmsDev mailing list
> OvmsDev at lists.openvehicles.com
> http://lists.openvehicles.com/mailman/listinfo/ovmsdev

-- 
Michael Balzer * Helkenberger Weg 9 * D-58256 Ennepetal
Fon 02333 / 833 5735 * Handy 0176 / 206 989 26

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