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CANBus Hardware Setup. CANBus. CANBus is a control system method that can be used instead of the conventional PWM system. It uses RJ12 cable, which is similar to ethernet cable, to link Jaguars together. Advantages. Ethernet cables are more robust than PWM’s
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CANBus CANBus is a control system method that can be used instead of the conventional PWM system. It uses RJ12 cable, which is similar to ethernet cable, to link Jaguars together.
Advantages • Ethernet cables are more robust than PWM’s • Less wire is required because the cable runs from one Jaguar to the next • Jaguars can handle PID loops, freeing processing on the CRio
More Advantages • Jaguars in CAN can have Potentiometers or Encoders wired directly to them. • CAN Jaguars can control motors just like normal jaguars, but they can also control them according to position, voltage, speed, or RPM.
Disadvantages • If one cable fails, the rest of the chain fails • Only 20 ft. of cable may be used • Only one Pot. or Encoder may be used per Jaguar • Only 16 Jaguars (max.) may be used.
Things You’ll Need • RJ-12 Cable, Connectors, and Crimper • At least one Black Jaguar • Two 100 ohm resistors • Modular Adapter: RJ-12 to DB9 Female (Digikey Stock No. 046-0003-ND)
Making the Adapter • The DB9 to RJ-12 adapter will need to be assembled once the pieces are purchased. The following table tells which pins from the DB9 end go to which wires on the RJ-12 end.
Placing the Adapter • The adapter should go on the end of the CRio, by the Ethernet ports.
Termination Because CANbus is a bus system, it needs termination on either end of the network with a resistor. This means that on the cable connecting the adapter and the black Jaguar (or even inside the adapter), the Red and Green wires (wires 3 and 4) need to be bridged with one of the 100 ohm resistors. The second resistor will be used later.
Crimping the RJ-12 Cable To make an RJ-12 Cable, take one end of the cable and strip about ¼ inch of the external casing. DO NOT strip the individual wires. Insert the wires according to the diagram below (1 is white) and crimp.
The Other End • When making RJ-12 cables, each end is crimped with the wires in the same order. This means that if you look at the cable, the ends will look upside-down from each other.
Connecting the Jaguars Each Jaguar will connect to the next in the network, as shown below. The power cables hook up as normal.
Termination • In the last Jaguar, there needs to be a terminator plug where the next cable would be. The terminator plug is simply an RJ-12 or RJ-11 connector with the ends of a 100 ohm resistor crimped into the center 2 pins.