Exchanging data via the CAN bus

In this section, we will see how we can use the CAN bus on our embedded kits using the transceiver-less connection only (in fact, using a transceiver is trivial; we just have to add one without any other software modifications). We'll see how to use both on-chip controllers on an external one connected via SPI to the main CPU.

Using the on-board controller

To do a transceiver-less communication with the on-board controller, we have to use the BeagleBone Black and the SAMA5D3 Xplained boards connected as shown in the following diagram. The circuitry has been realized considering what we said regarding the transceiver-less issues:

Note

The resistor is set as R=100KΩ.

At this point, we have to enable our CAN interfaces as described earlier for both the BeagleBone Black and the SAMA5D3 Xplained. For the first board ,we can set up the interface as shown here:

root@bbb:~# ip link set can0 up type can bitrate 50000
                        loopback off triple-sampling...