Is this bit stuffing correct on CAN Bus?

Question

I'm implementing a CAN Bus receiver in VHDL under 250 kbit/s, and a curious frame turned up. This is finishing the field of CRC, the last under the application of bit stuffing. And I have:

...011111000001

I don't know if that final 1-bit is the beginning of the CRC delimitter field or a bit stuffed to will be ignored.

Any ideas?

Thanks!

After 5 bits of the same polarity, CAN will add a bit stuffing bit of the opposite polarity. However, I don't think it adds bit stuffing from the CRC delimiter and beyond. — Lundin, Oct 21 '16 at 07:06

score 2 · Accepted Answer · answered Oct 24 '16 at 07:59

Finally, I found the answser!

The final bit is a bit stuffed, because the previous five zeros are inside of CRC field. The next bit to final 1 is the CRC delimitter bit, and next the ACK slot bit.

Now the ACK is sent in its correct place and no error is present in bus.

Is this bit stuffing correct on CAN Bus?

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