Transclusion: Debian: iMX7: CAN Bus

Software installation

• Use the following command to install can-utils:

root@cl-rootfs:~# apt-get install --no-install-recommends can-utils

Loading CAN modules

If the FLEXCAN driver and/or Raw CAN protocol compiled as module(s), they must be loaded prior to enabling CAN interface.

• The FLEXCAN driver gets loaded automatically. Make sure it is loaded:

root@cl-rootfs:~# lsmod | grep can
flexcan                102  0

The FLEXCAN driver can be loaded manually:

root@cl-rootfs:~# modprobe flexcan
30a00000.can supply xceiver not found, using dummy regulator
flexcan 30a00000.can: device registered (reg_base=f5a00000, irq=277)
30a10000.can supply xceiver not found, using dummy regulator
flexcan 30a10000.can: device registered (reg_base=f5a10000, irq=278)

• Load Raw CAN protocol module:

root@cl-rootfs:~# modprobe can-raw
can: raw protocol (rev 20120528)

CAN interface configuration

It is recommended configure the CAN interface, with the iproute2 utilities.

• To make sure the right ip utility is used, run:

root@cl-rootfs:~# ip -V
ip utility, iproute2-ss151103

• Configure the CAN interface bit-rate to 125 Kbits/sec (values of up to 1Mbit/sec are supported):

root@cl-rootfs:~# ip link set can0 type can bitrate 125000

• Enable the CAN interface:

root@cl-rootfs:~# ip link set can0 up
flexcan 30a00000.can can0: writing ctrl=0x0b312005

Send/Receive packets

Use cansend and candump utilities to send and receive packets via CAN interface.

• Send standard CAN frame (on the first device):

root@cl-rootfs:~# cansend can0 111#1122334455667788

• Send extended CAN frame (on the first device):

root@cl-rootfs:~# cansend can0 11111111#1122334455667788

• Dump all received data frames as well as error frames (on the second device):

root@cl-rootfs:~# candump any,0:0,#FFFFFFFF
  can0  111  [8] 11 22 33 44 55 66 77 88
  can0  11111111  [8] 11 22 33 44 55 66 77 88