[FrankJ]

The first documentation in the Crio days suggested regular 6 wire flat phone cable for the canbus. Only two wires is needed for the CAN but the RS232/can converter was in the first Jaguar in the chain so you needed 3 wires for the RS232 to the Crio. (unless you where using the Cross the Road ethernet/can convector) The CAN physical layer standard (CIA 102) allows flat or twisted pairs. Both NI and TI have application papers saying that short stub lengths connecting the devices to the daisy chain is OK. I know a lot of people blamed the com wiring for motor control problems back in the day, but I expect it was more programming issues. The FRC implementation of CAN had a lot of gotchas in it. Not yet mentioned is stranded wire is better than solid from a physical stand point.

So what is my point? The com wiring is pretty forgiving, especially the short length in you typical FRC robot. But if you do right from the start, it is not one the things you have to trouble shoot when having robot problems. You can use flat or twist pairs. My preference is for twisted. You can get away stub lengths that approach what looks like a star configuration. My preference is to keep it flat as possible. You want to avoid running the CANBUS parallel to the motor control wires. You want to securely splice the CANBUS wire together either using connectors or terminals. Loose wires will cause com errors.