SB-SOM: HOWTO: CAN Connection

SB-SOM top view

SB-SOM bottom view

Description

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.