SB-SOM: HOWTO: CAN Connection

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SB-SOM top view
SB-SOM top view
SB-SOM bottom view
SB-SOM bottom view


The CAN bus interface available with most SB-SOM is accessible through the P5 100mil header. Use jumper wires to connect your CAN node with SB-SOM CAN bus interface as outlined in the table below.

P5 Pin Signal Name Description
34 CAN_GND Connect to GND terminal your CAN bus interface
32 CAN_L Connect to CAN_L terminal your CAN bus interface
30 CAN_H Connect to CAN_H terminal your CAN bus interface
28 CAN_VCC (5V) If your CAN bus interface requires 5V power, Connect this pin to your CAN bus terminal. Otherwise, Do not use.

120Ω CAN bus termination

CAN bus termination on a node is required with some CAN bus topologies while forbidden with others. SB-SOM board revision 1.2 (or later) features the P23 connector which can be used to enable/disable 120Ω CAN bus termination implemented onboard SB-SOM. Set the bus termination most recommended for your CAN bus topology using P23 connector. Revisions 1.1 and 1.0 of SB-SOM do not provide the CAN bus termination at all.

  • Place a jumper cap between pins 2 and 3 of P23 to enable 120Ω CAN bus termination.
  • Remove the jumper cap to from pins 2 and 3 of P23 to disable 120Ω CAN bus termination.

More Details: Connector P23, Connector P5.