I recently started a small side project at work in which I was in need for a microcontroller. In almost every project I did in recent years I used a ESP32 out of convenience or need for wifi. However in this project Space was an issue, so huge module like that was not very appropriate. I just need a few I/O pins and maybe a serial port for debugging, that’s it.

I have access to a lot of EtherCat components, among them the brand new OMRON 1S series servo drives. Obviously I wanted to get them working in LinuxCNC but there were no drivers for them. There were drivers for the OMRON G5 series drives however. So I compared the PDOs used in that driver with the PDOs of the 1S series. Turns out they are identical 🤓 I cloned the git repo of linuxcnc-ethercat and began to tinker around.

I’m planning to use a Barth Elektronik STG-850 mini-PLC for a project. The main reason to pick this PLC was the size of just 93x45x15mm, the low price of 150€ (low for an industry grade PLC) and the claim to support “Open Source programming” using the Arduino IDE. In the meantime that claim is no longer on their website and the manual for it is gone as well. There is a GitHub repo that was linked in that manual which provided the integration into the Arduino IDE. Unfortunately there was no activity since 2017 and the manual said a Arduino version 1.8.3 is needed.

In my previous post on this topic I successfully managed to get LinuxCNC with EtherCat running on a Beckhoff CX2040. That was over a year ago and since then I didn’t have the time to dig deeper into the matter. Until now, and a lot has changed in the meantime …

Back in 2016 when we completed building our house I installed a home server in my basement networking rack which I always refer to as the “open wound” 😁 That’s because It is mounted on a laser cut sheet of zinc coated sheet metal that forms a rack mount shelf and looks hacky as hell. These pictures are from day 1 and some things have changed in the meantime.

All my services that I selfhost are docker containers which I manage using docker compose . Until recently I had all of them in one big docker-compose.yaml file which started to be a hassle to manage. For a while I looked for ways to split the file into multiple files but nothing really statisfied me. I even mad an attempt to to have a bash script that makes use of the -f parameter to merge multiple files which kind of worked but had some strange side effects such as containers were not added to networks every now an then and depends_on didn’t work.

I switched from Mikrotiks wAP accesspoints to TP-Link Omada EAP650s a while ago (check out my blog post ). As explained in that post, I started self hosting Omada controller which is the management software for these APs. But I never mangaged to get it working behind caddy , my webserver / reverse proxy. So it ran as a docker container on my home server with exposed ports without HTTPS. In my home environment that’s not a big deal but it always felt wrong.

I ran Pi-hole as a docker container for several years now in order to block various unwanted DNS requests in my home network. That kind of worked but I had a lot of issues that I wasn’t able to solve or at least to figure out what caused them. A few days ago this went sideways in a way that my entire network became unusable. So I decided to get rid of Pi-hole and use the normal DNS servers provided by my ISP.

I got an old Beckhoff CX2040 that was no longer in use into my hands and decided to try if I can get LinuxCNC with EtherCat support running on it. My setup consists of the CX2040 itself and a CX2100-0004 45W power supply that also features the E-Bus connector for additional I/O terminals. I had an EL3255 5 port pontentiometer terminal and a EK1110 bus connector laying around and used those for a first test.

I run a Mikrotik router in my home network setup and several Arch linux machines. It bothered me that the hostnames of the Arch linux machines didn’t show up in the Mikrotik DHCP server leases table. Almost all the other network devices showed up nicely which makes it quite easy to identify them. I fiddeled around witch avahi, systemd-resolve and varous config files but nothing seemed to work. After a lot of searching I finally came accross this post in the Arch linux forums.