What resistance should we use for the terminator? Every source says 120 ohms but apparently we used 22 ohms last year and it worked

Technical CAN
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Both ends of the CAN bus should have a 120 ohm resistor. There is one built-in to the RoboRIO as well as the CANivore. They are also built in to the CTRE PDP and Rev PDH and can be turned on either by jumper(CTRE) or switch(Rev).

They serve to cancel out reflections of the electrical signals at the ends of the bus and work best when the correct value is used.

With the two 120ohm resistors in parallel, the total resistance on the bus should be right around 60ohms.

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Use 120. Easy place is to find one for your primary bus is the Terminator resistor built into the PDP/PDH.

Not surprised your 22 worked, I’ve gotten away with a 480 thru hole resistor jammed into a female header pin connector on the low speed bus on the RIO… but the CANivore needs a nice soldered 120 to be happy, so just get in the habit of doing it right.

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