Team 303 used all CAN as well. We had 8 motor controllers, 6 Black Jaguars, and 2 Tan ones. There are some real issues with using CAN, as others have mentioned. Lost configuration on brown out, not stellar PID controls, and timeouts of messages on the bus - as reported by the cRIO. In addition, you have a new single point of failure in either the 2CAN, or the serial cable. Lost of that device or cable will render your robot dead in the water.
We also had a case where one of the Jaguars on the bus went crazy and flooded the bus, causing us to loose comm with all of the Jaguars.
One failure case that we had (and is the reason for the 2 Tan ones) is on our shooter motor. If you rapidly changed the setpoint on our shooter motors, the Black Jaguars would eventual stop working completely, and required a reset, and reflash of the firmware. The Tan ones would reset and this triggered code which reloaded the configuration and start working again.
Lots of people don't like the high current shutdown of the Jaguars, and I'd like to have it be tunable but should you really be running the motors at such a high current? The victors would reboot as well but they rebooted quickly, and had no configuration, and would keep trying to do what you told them until they burned out either the motor or themselves. Seems better to save the equipment, and fix the high current issues.
It's a bit sad, really, because FIRST has already reached other countries and there are some U.S. states that still are unaware of what FIRST is!! - tribotec_ca88 [more] 
30-04-2012, 15:22
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