Hey, everyone! The inspection checklist says that the Pneumatic Control Module must be connected to the RoboRio via CAN bus, it also says that the RoboRio must be connected to the Power Distribution Panel via CAN bus, however, our RoboRio only has one CAN plug.
The roboRIO is at one starting end of the CAN bus.
Not in the middle somewhere.
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As the comment above says, you must start the CAN bus at the PDP, run it through the different things that need to be connected, and then end at the robo-rio.
The way a CAN bus works is by daisy chaining multiple items together. There is not a separate CAN port on the roboRIO for each device, there’s just the starting ports. Each device from then on should have 2 of each CAN connection.
The simplest way to set up CAN if you’re new to it is to use the roboRIO as the “start” and the PDB as the “end”, with every CAN device connected in between. The roboRIO must be the “start”, and having the PDB as the end lets you take advantage of the internal resistor inside the PDB which reduces noise on the bus.
Not entirely true. The CAN bus mist start at the roboRIO and end with a 120 Ohm terminating resistor. The PDP has this resistor built in if you put the jumper to ON, which means it’s often convenient to end your CAN bus at the PDP. If your robot is set up in such a way that it’s not convenient to end with the PDP, you can end with any device with your own resistor at the end.
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