Using CAN in a star configuration

[jee7s]

Originally Posted by Thad House

Is it possible to use CAN in a star configuration. Like having one output to the PCM and PDP, 1 output to a few talons, and another output to a few other talons. I know you would need termination resistors on each line, but other then that would it work?

Really risky. You're going to end up with all sorts of reflections on the line that will tend to corrupt the CAN signalling. The signalling really does depend on a properly terminated transmission line of proper characteristic impedance to work properly. There's a boatload of specs on how to do it properly, most of which are summarized by TI here: http://www.ti.com/lit/an/slla270/slla270.pdf

Succinctly, you want a 100 ohm characterisic impedance (twisting wires together does that) and 120 ohm terminations. There are other factors like stub length and number of nodes that the document addresses. But, fundamentally the bus needs to be that differential pair with the 120 ohm terminations at each end and drops along the way for each device.