Two Hub Motors Illegal Hall State

Hi, I am setting up a new ODrive with two hub motors that are giving me troubles when I attempt to run them both at the same time. I am using hall switches and each motor is tuned fairly well and runs fairly well individually but as soon as I attempt to start the second motor I get an encoder error:ERROR_ILLEGAL_HALL STATE.

I also notice that most of the time I can start either motor and the other motor will fault mostly when I attempt to start it but ocasionally I get the error before I start the second motor. The first motor continues to run without issue.

Has anyone seen this before? Can anyone offer suggestions as to why this may be occurring and how to troubleshoot?

Yes, I have seen this. It is caused by noise induced on your encoder wires.
Add 3x 22nF capacitors to GND on each of your encoder inputs A,B,Z.

Hi @towen, thanks for pointing this out. I scoped the encoder lines and they were very noisy. I added some caps and that seemed to clean them up very nicely.

Thanks again for the help!

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