[beagleboard] Re: Running CANbus on BBB w/ Chipsee BBB-EXP-C 7" display cape

Well, I think using python for a timing critical application is probably a bad idea. Out of all languages, compiled, or not, Python is potentially the worst performance wise. It can be 80x + slower than javascript + google’s V8 engine ( Nodejs ) even.

With that said, I think Nodejs would be a bad idea too. I’ve had some experience with Nodejs, and latency can sometimes be a problem.

Personally, I’m using C. But I have no idea of what your development constraints are. C++ could probably work well too. But since you’d be using C libraries for socketCAN . . .

I’ll assume for now since you’re using the cloud9 IDE, that you do not have another Linux machine, physical or virtual to work with ? Anyway, I personally think C is the way to go. Far less abstraction to get in the way, and socketCAN is fairly well documented.


By the way, I’m still learning a lot about all this too. For all intents and purposes this is the first major application I’ve written on Linux. Also a couple months ago I knew absolutely nothing about the subject. Which for me includes socketcan, J1939, NEMA 2000 / NEMA 2000 fast packet.

Anyway, my point is: If I can do this, I’m sure you can too.

Hey SuperD I just realized something.

Look at the output of my ifconfig for our BBB with logic supply serial / CAN cape. Notice anything odd ? As in 100% dropped packets ? heh

I just dawned on me, that since the BBB last started we’ve not used the CANBus at all. It is attached to our external CAN device, but no socketCAN apps ( including candump ) have been run since last restart . . .Which means I believe this is just normal behavior.

Try it yourself. restart your BBB, and do not use candump just let it sit there for a little while. I’m willing to bet you’ll also notice 100% packet loss.