Turned out this was no hardware issue but a scheduler problem: the CAN rx and vehicle rx tasks were not scheduled often & fast enough to consistently keep up with the 10 ms period.

After assigning the CAN RX task to core 0 and raising the vehicle task priority to 10, there are no more TX overflows, and my charge control override works perfectly.

Geir, I don't know if that helps with your can2 issue, but it's worth a try.

Regards,
Michael


Am 31.12.2017 um 19:59 schrieb Michael Balzer:

And TX overflows actually do occur quite often, without a plausible cause:

OVMS > can can1 status
CAN:       can1
Mode:      Active
Speed:     500000
Rx pkt:                  133146
Rx err:                       0
Rx ovrflw:                    0
Tx pkt:                   53238
Tx err:                      95
Tx ovrflw:                  498
Err flags: 0x12c00

In this case, a TX occurs every 10 ms on a 500 kbit bus -- plenty of time for the buffer to get sent. I'm looking into that.

-- 
Michael Balzer * Helkenberger Weg 9 * D-58256 Ennepetal
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