Hello, I am a programmer with a problem. I have searched long and far for the information on how to use CAN cables. Can someone please post how to or refer me to a site which will. Thanks
-Confused Programmer Team 910
Our team is working on developing a wiki with information to pass on to future members. As far as I know the page documenting CAN is complete.
http://coolhub.imsa.edu/cybercollab/web/robotics-documentation/documentation/-/wiki/Main/Controller%20Area%20Network%20%28CAN%29
This wiki is a work in progress, and as such several areas have not been completed.
http://www.luminarymicro.com/jaguar
Luminary Micro is the manufacturer of the Jaguars. This page has information about the Jaguar. You want to look in “Getting Started (MDL-BDC24)”. There is information about the cables in the appendix.
The cables are very important to get right. You will not find these cables in your neighborhood hardware store. Make and test the cables carefully. This was a huge source of trouble for us.
I wrote an article on the workings of black jaguar style CAN
http://www.chiefdelphi.com/media/papers/2433
keep an eye out for an updated version… will upload tonight.
everything one would care to know about the electronic cabling and some tips based on my screw-ups (so you don’t make the same blunders) and successes (so you can do the same). IMHO, required reading for anybody using the black jaguar for CAN.
Emphasis mine.
CAN cables are simply 4-wire telephone cables. The technical name is RJ-11 (it might be 12, make sure they have 4 shiney things in the end). To use them with the jaguars, you make a serial-can cable (don’t know how anymore ::rtm:
and then plug one end into a BLACK jaguar on the side with the funky |o|o| symbol in it. Then you get another cable, plug it into the other CAN jack on the jaguar, and then onto the next jaguar. Note that only the first jaguar has to be black, the rest can be brown or green or purple.
Our team bought an RJ-11 crimper, so we can make as many as we want and we don’t have to search long and hard for a 4 inch cable.
rj-12 uses all six wires. it is what the serial adapter for the black jag uses. for how to make, refer to the article i linked in my last post, as i cover 3 different approaches to making the adapter.
the crimper is the same because every crimper i have seen will do RJ-12 if it will do RJ-11.
four wires will do for everything else… or if using 2can, everything.
It is very important to be careful. The cables are NOT standard off the shelf telephone cables. The connectors are reversed from the normal telephone cables. If the connectors are incorrect, your network will not work.
This is only important with the RS232-CAN adapter.
All regular cables are straight through; it doesn’t matter if the connector is reversed, so long as both ends match.
I’d really like to believe you, but, Appendix A of the MDL-BDC24 Brushed DC Motor Control Module Getting Started Guide for the Jaguar specifically says
Cables must be “straight-pinned,” which means Pin 1 > 1, Pin 2 > 2, and so on. This is also referred to as a reverse-cable because the tabs on the connectors are on the opposite sides of the cable.
It would be nice to hear that this is true and that you are specifically having success with cables that do not satisfy the requirements of the manual.
Yes.
I have an 8-foot phone cable which I’ve used successfully. It is “straight-pinned”, but does have the opposite color sequence.
EDIT:
I suppose I was unclear in what I meant by both ends matching. I was using it as a synonym for the term “straight pinned”, which had jogged my mind.
That sounds like a contradiction. I’m probably not understanding it properly. Can you clarify?
Sure.
On a CAN cable, the color sequence (for both connectors) is White, Black, Red, Green, Yellow, Blue, as read from left to right with the contacts facing up as if you were to plug it into a port directly in front of you.
Both ends of the cable are this way.
On a phone cable, the color sequence is Blue, Yellow, Green, Red, Black, White. Both ends of the cable are this way.
What makes the cable straight-pinned is not the color sequence on either end, but simply that the sequence matches for both ends when both connectors are held in the same orientation.
I hope that’s clear enough.
Right, but what confuses me is that you said the color sequence on your straight-pinned cable was opposite.
I hope that’s clear enough.
I still read “the sequence matches” and “opposite color sequence” as contradictory.