Dear developers,
this year there have been a lot of changes, and I guess the end of the year is a time for reflection. This year I have (once again) moved from Sweden to Germany for new opportunities. Every opportunity usually brings its challenges. Moving abroad is always a challenge, and I wouldn’t be honest if I didn’t say that I miss Sweden every day. This blog and my YouTube channel have been one way for me to think of something else than home.
One of the most anticipated products that Beckhoff has released this year is TwinCAT/BSD, which is Beckhoff’s new operating system which is an alternative to Windows for the PLCs. Did you ever want to play around/learn TwinCAT/BSD, but don’t want to spend the money to buy a PLC with it pre-installed? No worries, it’s entirely possible to run it fully virtualized in a virtual machine. Not only that, it’s also possible to run your TwinCAT 3 software in that virtual machine! I’ve created a step-by-step tutorial where I will show how you can run it locally on your PC. Start the video to join me on an adventure & let’s have some fun!
One of the things that have annoyed me ever since I started using TwinCAT is the fact that if you create an enumeration, it will automatically have a global scope. It will be accessible from all functions and function blocks. What’s even worse is that if you create a library project with an enumeration and include that library in another project, the enumeration will be visible there, too. This pollutes the namespace by creating unnecessary types. But no more.
Dear existing & future PLC software developers, I have published part 9 of my free PLC programming using TwinCAT 3 tutorial.
In this part we’ll learn how to use one of the most used Beckhoff libraries for various purposes. We’ll learn how to measure execution time of PLC code, how to use a FIFO buffer and how to combine the power of using a TwinCAT real-time program with an application running in user-space (Windows).
Today on this day five years ago, I published my first entry on this blog. These last five years have been an amazing trip, and the number of visitors has seen a steady growth.
Dear existing & future PLC software developers, I have published part 8 of my free PLC programming using TwinCAT 3 tutorial.
As TwinCAT 3 conforms to the IEC61131-3 standard, there are certain things it has to be able to do. The Tc2_Standard library has many of the standard IEC functions such as timers and triggers, which we will look into in this part of the tutorial.
Dear existing & future PLC software developers, I have published part 6a of my free PLC programming using TwinCAT 3 tutorial.
In this part we will start to look into the object oriented programming parts of structured text and IEC 61131-3 called function blocks, and I think it’s here things are really starting to get fun! For those that are Java, C, C++ or just “traditional” programmers, going into the realm of function blocks is like going from C-style structures and functions, and into classes in C++. With function blocks we can go from working in a procedural style programming into objected oriented style programming.
Almost two years after I created a pull request to include a default TwinCAT 3 .gitignore file into the official GitHub Gitignore repository, it has finally been accepted & merged into main branch. Download the file here.
You better not be in a hurry to propose changes! 😅
The user base for TcUnit, the free open-source PLC/TwinCAT unit testing framework, has grown enormously. Current estimates are that there are over 100 installations of TcUnit worldwide. Running an open-source project has for some moments taken all my spare-time to maintain the framework, and answer all the questions from the users (I’ve added an FAQ since). The most asked-for functionality of TcUnit that was missing was the possibility to run unit tests in a sequence/in order. Up to now, all tests defined in TcUnit were running in parallel, while in many use cases it was desirable to run the tests in sequence. Thanks to several fantastic contributors from the TcUnit community on GitHub, this is now available in TcUnit starting from version 1.2.
Dear existing & future PLC software developers, I have published the 5th part of my free PLC programming using TwinCAT 3 tutorial.
Arrays allow us to define types of variables that can hold several data items of the same kind. In this part of the tutorial we will look at a data unit type that allows us to hold several data items of different kind. We will also look at one of the basis of modularization and re-use in software development called functions. We will look at how we can get data in and out of functions, and we will also look at the difference between passing parameters by value and by reference. We will finish this part by writing our very first function!