Step 2: Setup SocketCAN Interface

Configure your CAN interface to communicate with the OpenArm motors. This step sets up SocketCAN on Linux to enable CAN bus communication. The electrical BOM contains the device we are using for experiments.

Prerequisites

Before proceeding, ensure you have the required tools installed:

sudo apt install can-utils iproute2

Find Your CAN Interface

First, identify your CAN interface device. List network interfaces to find your CAN adapter and look for interfaces like can0, can1, slcan0, etc.

ip link show

Setup the interface

Replace can0 with your actual CAN interface name and use a baudrate supported by you interfaces for the steps.

Option 1: setup manually

CAN 2.0 Mode

sudo ip link set can0 down
# configure CAN 2.0 with 1mbps
sudo ip link set can0 type can bitrate 1000000
sudo ip link set can0 up

CAN FD Mode (Recommended)

ip link set can0 down
# configure CAN FD with 5mbps
sudo ip link set can0 type can bitrate 1000000 dbitrate 5000000 fd on
sudo ip link set can0 up

Option 2: use setup scripts

The OpenArm CAN library includes convenient setup scripts, example usage:

# Navigate to openarm_can directory
git clone https://github.com/enactic/openarm_can.git
cd openarm_can/setup

# For CAN 2.0
./configure_socketcan.sh can0

# For CAN FD at 5mbps (recommended)
./configure_socketcan.sh can0 -fd -b 1000000 -d 5000000

Verify Configuration

Check that your CAN interface is properly configured:

# Verify interface is up and running
ip link show can0

# Monitor CAN traffic (optional)
candump can0

# Test monitoring
cansend can0 ...

Troubleshooting

If the interface configuration fails:

• Verify physical connections
• Verify driver installation for your specific CAN adapter
• Check dmesg for device logs
• Some serial based devices may need wrappers like slcand to be visible in ip link show
• Check supported bitrate values and device compatibility
• Load kernel modules like

  sudo modprobe slcan
  sudo modprobe can
  sudo modprobe can_raw