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Control Myxa with traditional CANbus protocol?

I’m an electrical engineer working on a project where we may need to use your Myxa ESC as a backup controller for an air compressor motor in our system if the BLDC on the prototype controller we’re having developed doesn’t pan out. The controller we’re getting utilizes traditional CANbus protocol in the sense that it needs to know the message id and bit field make up of individual data signals within 64 bit CANbus messages which we configure in a database file for ease of use (Google “Vector CANdb++”). Is it possible to use this standard type of CANbus scheme to control your Myxa ESC? We do not have the ability to modify the code of the controller to utilize a full UAVCAN layer as I’m able to understand it so far. That said, I’m extremely new to CANbus in general, let alone UAVCAN, so I could easily be missing something. It’s just that all the CANbus devices I’ve learned to interact with so far have very detailed documentation detailing the message id (usually in HEX) of each available message on the device along with the start bit, length, multiplier, etc for every data signal in the 64 bit message and I’m not seeing anything remotely close to that for the Myxa.

Hi Ethan!

What you are describing is only possible if you can ensure that the five least significant bits of the last byte of the CAN payload are incremented after every transmission. The UAVCAN stack uses that for duplicate rejection and management of redundant transport interfaces (it is known as the “transfer-ID”, you can find the details in the Specification).

Thank you for the response! My guess is we probably won’t have control over that but I’ll check into it. I have a feeling, if we do find your controller works best on our motor, we’ll just settle for using your PWM control option.

Take care! :slight_smile: