How does one wire up a CAN bus? I notice that devices (Cerb40II) has CAN1_TX and CAN1_RX, however, CAN bus is a differential pair. So why is it labeled TX and RX?!!? Also, do the devices need any external components to communicate on the CAN bus (e.g. resistors or external driver ics)?
Yes usually you need a can transceiver such as a 82c250. You will need also a can terminator if it’s the last device on the bus. I use to put a jumper to activate or not the terminator.
Gadgeteer specifications include a CAN socket type which exposes the CAN TX and CAN RX digital lines. This leaves the option of selecting a transceiver up to the module. For example, this can be a High Speed Dual Wire, Single Wire or even Low Speed Fault Tolerant.
This module offers a High Speed, up to 1mbps, dual wire transceiver. The required 120ohm termination resistors are already included on the module but can be disconnected by desoldering the SMT jumper.
@ leforban - The board I’m trying to build contains the last device in the chain. Explain Terminator?
I’m looking at this device from ST: L9616-TR