Quote:
Originally Posted by slijin
I have to agree with this. If you're not going to use CAN, stick with Victors. If you think CAN is imperative for your application, then add Jaguars to the mix. We had Victors for everything except our shooter motors, which were controlled with Jaguars running their infamous closed-loop PID.
One point that I've never seen mentioned before and I feel really needs to be said is that if you use CAN, make sure you have people in the pit crew who know how to troubleshoot it. There are many teams that never run into issues with CAN (and that's great for them) but there are infinitely more teams who experience incessant issues with CAN. Jaguars are much more complex devices than Victors and have far more failure points. Familiarity with and knowledge of CAN is an absolute must, and there are only so many issues that can be caught during build season (like finding out that your CAN loop takes longer to execute than the allocated loop time).
We had one incident at our first regional where only after ten minutes of frustrated troubleshooting did we manage to isolate the issue to a bad Jaguar in the CAN chain (the traditional move-and-replace-stuff method just barely caught this), which for some (still unknown) reason refused to interact with other Jaguars on the network (no, it wasn't a contact pin issue; later off-board testing yielded inconclusive results as to the source of the problem). If it wasn't for my and another programmer's familiarity with CAN (our lead programmer even had to step back, due to his unfamiliarity with the issues at hand), we may never have caught the problem in time. I eventually handed it off at CMP to a TI rep who hopefully will be able to get back to us with more concrete results.
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Our debugging process usually involves checking lights followed by checking the 2CAN via a web browser. If that is reporting the Jag as being connected we blame the software guys and fix it. If not we blame the electrical guys and make them debug it. 9 out of 10 times the error is that someone had decided to use the CAN wires as a place to zip tie the 2CAN to. (This only happened once but it's too funny of a story) Using this process we are usually able to nail down an error fairly quickly.