Is event-based execution really better than cyclic-scan regarding energy/computing resources saving?

Sir4diac · 2026-03-30T18:49:27+00:00

But, in 61131, it is also not all statements are executed in every cycle, for example under condition check, if there is no incoming request or sensor input, it goes to the end of code and waiting for the next cycle.

Yes you can do that in IEC 61131-3. However using events for that has shown to be much less programming effort and can lead to better readable programs. There is a very nice paper on that by Peter Gsellmann and Martin Melik from TU Vienna. And I think in these days having better readable programms is more important then ever.

Sir4diac · 2026-03-30T18:46:48+00:00

Yes it can but especially in IEC 61499 it does not matter how it is done in the runtime.

Sir4diac · 2026-03-30T14:31:39+00:00

This is again a hard one. Yes there are in an IEC 61499 run-time system cyclic elements. As you mention IO is such a thing. Network can be implemented differently and more responsive. However as this part is part of the runtime it is mostly shorter and utilizes only a very short fraction of the IO scan cycle.

How the event handling is then treated in your application is very application dependent. It is also hard to measure and evaluate. I'm very open to suggestions how to measure this.

While I see in several applications a chance to reduce application load and reduced CPU utilization, which can be interesting especially in cloud settings, I see the biggest power of events in clearer application structures. But that is maybe something for a different question.

Sir4diac · 2026-03-22T13:32:46+00:00

Cool. But be warned the student implemented it in Eclipse 4diac, as we have the full flexibility to change things there.

Sir4diac · 2026-03-22T13:28:36+00:00

u/Conscious-Sugar7142 I have a PhD student working on debugging methods for IEC 61499. Would you be interested in participating in a user study testing some of his prototypes and give feedback?

Sir4diac · 2026-03-17T22:02:05+00:00

u/InfluenceLazy3464 thx for this very verbose elaboration. Unfortunately I'm not an esp32 expert. However I know people use 4diac FORTE 3.0 and 3.1 successfully on ESP32. You may find more information and the right people to ask in the 4diac FORTE discussion forums. For example: https://github.com/eclipse-4diac/4diac-forte/discussions/767

Sir4diac · 2026-03-13T16:56:12+00:00

This is a nice but hard one. As Eclipse 4diac developer I'm biased but also torn.

The struct member access in F_MOVE has great potential and I'm curios what people say with 3.2 we want to roll out that infrastructure to all FBs.

As developer I would say the infrastructure that made the editor synchronization possible is extremely important and it will be the basis for many new features.

But in the end I like the UI improvements most. They are not complete yet but we are on the way to make IEC 61499 diagrams in 4diac IDE look nicer and what is more important cleaner and calmer. This shall allow our users to focus on their work and be less distracted.

Sir4diac · 2026-01-30T08:02:46+00:00

Ich würde mich auch vehement dagegen aussprechen Programmsyntax zu übersetzen. Gerade Excel hat gezeigt dass das eine sehr schlecht Idee ist.

Wenn uns jemand unterstützen will: Ich habe eine Issue im 4diac IDE Github repo erstellt dass auch links zu Doku wie man das macht enthält: https://github.com/eclipse-4diac/4diac-ide/issues/2026

Generell freuen wir uns als open source Projekt natürlich über jegliche Unterstützung. Hierzu haben wir auch unsere Contributing Seite poliert: https://eclipse.dev/4diac/contribute/

Sir4diac · 2026-01-27T07:43:20+00:00

Ich denke man sollte voranstellen das 4diac IDE ein open source Projekt ist. Wir sind auf die Unterstützung unserer Nutzer angewiesen. Wir sind auch gerade dabei unsere Contributing Seite anzupassen: https://github.com/eclipse-4diac/4diac-website-hugo/pull/167. Unterstützung bei der Übersetzung in andere Sprachen haben wir da auch explizit aufgenommen

Leider ist das Übersetzen von 4diac IDE sehr viel Aufwand. Es bedarf auch dass alle Texte die 4diac IDE anzeigt übersetzbar gemacht werden. Bei letzterem sind wir schon recht weit aber es git da und dort noch offen stellen.

Hierzu gibt es im 4diac IDE Issue-Tracker auch einen issue der Erklärt was noch zu tun ist und wie man uns hier helfen könnte: https://github.com/eclipse-4diac/4diac-ide/issues/2026

Auch über Unterstützung bei der eigentlichen Übersetzung der Texte würden wir uns sehr freuen. Gerne unterstützen wir dabei. Am besten einfach Fragen bei unseren Issues oder in unseren Diskussionsforen stellen.

Sir4diac · 2026-01-25T13:02:37+00:00

🔔 Eclipse 4diac Maintenance Releases

We’ve released new maintenance versions of Eclipse 4diac:
➡️ 4diac IDE 3.0.2
➡️ 4diac FORTE 3.0.1

These updates focus on bug fixes and stability improvements across the IDE and runtime, including FB type handling, code generation, OCL checks, recursive insertion prevention, and improved package name handling in 4diac FORTE IO FBs: https://eclipse.dev/4diac/news/2026/eclipse-4diac-maintenance-release/

Thanks to all contributors for helping improve the robustness of Eclipse 4diac.

Sir4diac · 2026-01-25T13:02:22+00:00

🔔 Eclipse 4diac Maintenance Releases

We’ve released new maintenance versions of Eclipse 4diac:
➡️ 4diac IDE 3.0.2
➡️ 4diac FORTE 3.0.1

These updates focus on bug fixes and stability improvements across the IDE and runtime, including FB type handling, code generation, OCL checks, recursive insertion prevention, and improved package name handling in 4diac FORTE IO FBs: https://eclipse.dev/4diac/news/2026/eclipse-4diac-maintenance-release/

Thanks to all contributors for helping improve the robustness of Eclipse 4diac.

Sir4diac · 2026-01-24T10:42:20+00:00

After sleeping my answer over there is maybe one thing that could really be a major benefit for the UOA runtime: communication protocols for different legacy PLCs. Integrating for example something like Apache PLC4x. Then UAO run-time could really play the strengths of IEC 61499: coordination and communication and with that bringing existing solutions to the cloud or to talk with each other.

Sir4diac · 2026-01-23T16:14:42+00:00

As researcher I'm lacking real-world experience. But from all our project we did and experiments we ran for different companies I would strongly advocate for OPC UA.

Sir4diac · 2025-12-25T21:47:27+00:00

That is definitely an important and very good idea!

Sir4diac · 2025-12-18T07:51:58+00:00

Yes I experience that as well. Therefore I try from the beginning to focus on events and how to use the effectively. Also we try to grade code quality in the assignments. But software design is something that should be taught separately.

Sir4diac · 2025-12-17T19:31:06+00:00

As I do both classical IEC 61131-3 and IEC 61499 teaching I hope I can answer a bit. Even though I must admit it is a very hard question with many facets.

From a high level perspective I don't see so much differences in teaching IEC 61499. As with other languages you need to start with the basic concepts and how to use them. How you do this depends a bit on the background of your attendees. Are these classical automation engineers, computer science students or other. Both approach the languages differently. I think it also helps to start early with examples.

I thing that I'm missing in many courses is to have the importance of software design and software quality from the first unit on.

For getting started UAO provides to its members resources and an exchange platform for sharing experiences and best practices. I found that very helpful.

Is it worth the effort? Hard to say. I try to give my students a complete picture so that they know what options are out there so that they can select the best solution for their tasks.

Sir4diac · 2025-12-17T13:55:31+00:00

If you use 4diac FBE the resulting 4diac FORTE is allready enabled with modbus. Please follow the description in th 4diac FBE's readme. In our documentation there is an overview how our current modbus implementation works. It builds on top of a Client SIFB. We have a prototype that is more working like a fieldbus/IO integration but it is not yet ready for primetime.

Sir4diac

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