Posts by ALbert Mietus


practice-time:2 * 1 hour

The publish-subscribe architecture-pattern is very popular to route messages, according to WikiPedia. It is used much more generic, however. This workshop shows how to use it in an embedded application, or another single process application.
Then it becomes a HighTech (embedded) software design pattern.

We start with a simple implementation of Pub/Sub. You can experiment with that (Python) code and/or port it to your favorite language. Then, you are asked to design a cached, distributed version. Which is a bit more ambitious. And even though the result is probably pointless, it’s a great Design-Exercise and a lot of fun!

It will help you to understand Pub/Sub, help you to use it in embedded software. Eventually, you may need Pub/Sub in a distributed environment. Then, it is better to use one of the existing ones, like DDS (Data Distribution Service); which more efficient and even RealTime!
But, by knowing how to implement it and are able to design it, will help you to use it for the better

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practice-time:2 * 1 hour

This workshop is about the ThreadPoolExecutor (‘TPE’ for friends): a pool of workers implemented with Threads. This is a modern, advanced design-pattern available in many languages.

You will get an introduction to the concepts, to be able to use the ‘TPE’. Also, we study Python implementation, to practice design-analyse.

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Requirements Traceability

study-time:1 hour

Requirement-Management, and especially “Tracking Requirements” isn’t that complicated, but it needs some discipline. Often that discipline is replaced by a tool, which is encouraged by tool-vendors. That hardly ever works.

This blog introduces requirements traceability in a conceptual, but pragmatic way. It shows –as a demo– what a team has to do (defining requirements and describing the relations) and what the benefit is. It assumes a (more or less) agile way-of-work and shows how it can become lean. A small investment in good requirements definitions makes validations a lot easier.

And yes, it used a tool: a free one; as part of the documentation-system that is used for this side. An structured, version-controllable, textual way to write documentation, including all requirements. With a plugin that can visualize all specifications and their relations.
Those “particulars” will be shown too.

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De Embedded Linux Expert bestaat niet

reading-time:4 minuten

Regelmatig krijg ik ‘Embedded Linux Experts’ aangeboden; bijvoorbeeld voor het HTLD-team (HighTech Linux Delivery). Vaak zijn goede mensen, met Linux ervaring; maar toch niet de mensen die ik zoek. Het blijkt erg lastig voor niet direct betrokken, om de juiste experts te spotten. Daarom een paar hints waarmee je “de” Embedded Linux Expert herkent. Immers, alleen het woordje ‘Linux’ op een CV is onvoldoende!

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dPID: A Python ‘homework’ exercise

practice-time:1 hour

This is an optional exercise for the python-3 workshops: program a discrete PID-controller.

A basic class definition is given; which has to be tested and implemented. By starting with the test-part, which is advisable anyhow (the TDD approach), the exercise starts simple.

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