CAN Wiring

How do we go about wiring the CAN?
We currently are still running*** on the KOP 4 Cims, Victor SPX motor controllers. Daisy Chain is our current route. I have connected the Victors to each other, and i ended up with 2 wires, a male and a female.

Wiring Diagrams


I know that one has to go to the PDP, and the other into the PCM, and from the PCM, to the PDP. But since SPXs have the pins installed, how should we plug into those electrical components?

Rio <-> Speed Controller <-> Speed Controller <-> PCM <-> PDP

*** We plan on switching to Falcons later on, but for current reasons, we are going ahead with the 4 Cims + Victors.

I guess I’m not certain I understand what you’re asking. What you’ve described sounds perfectly fine, though I don’t know what you mean by this:

To answer your question as asked, you simply connect yellow to yellow and green to green, daisy-chaining each of the devices to the next until you run out.

Also, please note that device order does not matter. The only requirement is that you have a 120 Ohm terminating resistor at both ends. The RoboRio and PDP (with the jumper set correctly) will provide this by default, which is why they should be at the ends of the bus.

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He means that there are PWM plugs attached to the ends of the CAN wires.

If you don’t have the capability to make your own PWM cables, your best bet is to cut the connector off of the first and last SPX, strip the wires, and then plug them in. If needed you can also solder them to connect them to the right wires as well (or twist them, or use lever nuts, or another kind of crimp that your team has).

We made cables with the PWM connector on one end and bare CAN cables on the other end so that we wouldn’t have to cut the connectors off of our Falcons.

OHHHH yeah, that makes sense.

Yes, do exactly what @amboyscout suggested. Either crimp your own connectors on, or cut the connector off and splice the wires yourself.

According to this document, the Victor SPX’s have male pins on one pair of the CAN wires and female pins of the second pair. Just plug the connector with male pins of the first Victor SPX into the connector with the female pins of the second one…

I don’t know if the male pins will fit into the Wiedmuller connectors of the Roborio and PDP. If they do not, you can take a PWM cables with male and female connectors and cut them to make adapters.

It would be best to use a small zip tie to keep the connectors together since this type of connector does not have a latch. You will have to pass the zip tie between the wires coming out of each connector. If this is not clear, I will try to remember to take a picture and post it here this evening.

Edited to add link to Victor SPX drawing

I can swap the places ‘endzones’ right? As in the PDP and the Rio? The start point would be

PDP <-> Speed Controller <-> Speed Controller <-> PCM <-> Rio

you can put them in any order you want, as long as the roborio is on one side and the PDP is on the other.

Just for clarity: the PDP with the termination resistor, or any old 120Ω resistor between high and low.

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We can reverse the slots where the VRM and PCM receive power from the PDP, correct?

VRM for your Radio (and only your radio) has to use one of the two sets of power push connectors connected to the 20AMP fuse, does not matter which. (R48)

The PCM controlling the compressor can be attached there as well (R48) or to one of the smaller wago connectors with a 20amp breaker. (R52)

I meant the black and red wires on one end of the PDP (non-battery end). On the 2017 diagram, the PCM is on the furthest right, and the VRM is in the center, with the Rio being far left.

Can we swap the PCM to be in the center and the VRM to be on the right?


Radio power.

This was in the KOP. I assume it’s for the Radio. If using this, we would plug into the VRM and still have the ethernet from the rio but in separate lines?

The blue line is the ethernet, the green is the VRM power line.

The grey ethernet cable is to limelight.

Correct. You can have both the barrel jack adapter and the POE connected to the VRM. Redundant power to the radio is your friend.


Is this ok if left like this? the PDP only has the one set of CAN

Yes, you just need to make sure the “TERM RES.” jumper is set to ON, which it looks like it is from your picture.

ok thanks

According to this picture, Victor SPXs can be stacked. Should you stack them?

Edit: We currently have thme in a row, screwed onto polycarb without an aluminum plate.

I have seen that done on quite a few robots. I think they were designed to allow the LED’s to still be visible when stacked. Long, thin zip ties would work too.