Update June 2026
Several things have happened recently:
1. the ethercat repository is not compiling the dkms module correctly.
2. A number of ethercat specific improvements involving changes to LinuxCNC (2.10), the linuxcnc-ethercat driver (2.98, 2.10) and the ethercat master have been made
3. A linuxcnc specific version of the ethercat master is now available at
github.com/linuxcnc-ethercat/apt
Until these changes are incorporated into the LinuxCNC installer, Ensure secure boot (UEFI) is disabled in your BIOS) and after installing LinuxCNC from the downloads page at
linuxcnc.org/downloads/
please proceed as follows
1. Remove the iGh repsitories
Code:
sudo rm /etc/apt/sources.list.d/science_EtherLab.list
2. Follow the instructions at
github.com/linuxcnc-ethercat/apt
to install ethercat
If this stil fails you may have UEFI (Secure boot) on your PC with the preempt_rt kernel (installed with linuxcnc) you need to do a bit more work. Open the spoiler:
obtain your mac address
Save the MAC address of the NIC to be used for ethercat
Update the ethercat config file to use that MAC address
Code:
sudo geany /etc/ethercat.conf
set your Master0 device to your MAC address and device modules to generic. Make these edits
Note at this stage only the generic driver is available under the Bookworm kernel
Code:
MASTER0_DEVICE="xx:aa:yy:zz:bb:cc"
DEVICE_MODULES="generic"
save and close geany
Note, we have found in some circumstances ethercat master wants to use the first NIC listed in ip a if multiple NIC's are installed
If you experience problems after installation is complere, swap your network cables around and edit the MAC address in ethercat.conf
Enter these commands to start the ethercat service.
Code:
sudo systemctl enable ethercat.service
sudo systemctl start ethercat.service
sudo systemctl status ethercat.service
sudo chmod 666 /dev/EtherCAT0
Ethercat should be running. If the above command is not found, you have a problem
You can list the slaves if you type
To ensure the ethercat port has permissions on startup. Create a udev rule
Code:
sudo geany /etc/udev/rules.d/99-ethercat.rules
Add the following:
Code:
KERNEL=="EtherCAT[0-9]", MODE="0777"
[code]
Save and exit, then type
[code]
sudo udevadm control --reload-rules
and reboot your computer.
Without this, on a restart, you always needed to chmod the ethercat port.
If you are using cia402 compatible drives:
Code:
cd ~/dev
git clone https://github.com/dbraun1981/hal-cia402
cd hal-cia402
sudo halcompile --install cia402.comp
so to test its working from Linuxcnc
If you don't have an xml config file yet (preferred), download an ethercat config file of mine from
github.com/rodw-au/linuxcnc-cia402/blob/main/ethercat-conf.xml
in that folder type:
Code:
halcmd loadusr -W lcec_conf ethercat-conf.xml
halcmd show pin lcec
You should see this and hopefully a few other pins displayed
Code:
Component Pins:
Owner Type Dir Value Name
4 u32 OUT 0x00000001 lcec.conf.master-count
4 u32 OUT 0x00000004 lcec.conf.slave-count
Let us know how you get on.
