I find that Finite State Machines have the same property - the concept is simple, even a child can grasp the basics, but then you can use FSMs to describe very complex and convoluted systems. I published four articles on this topic...]]> Tue, 21 Apr 2026 21:22:16 +0000 Massimiliano Pagani https://www.embeddedrelated.com/showarticle/1665.php Welcome to the fourth part of my two-part article on state machines (1). This post topic has been suggested by Miro Samek, who, in a comment to my first post, wrote: "The biggest issues are not so much with the state machine implementations [...]. Instead, the biggest issues are with the code surrounding state machines.".

Indeed Miro is right, many problems come from outside state...]]> Wed, 22 May 2024 12:48:33 +0000 Massimiliano Pagani https://www.embeddedrelated.com/showarticle/1645.php This is the third installment of my finite state machine in C++ series. In the first post, I introduced the subject of a state machine and how to go from a trivial but poor implementation to a more robust and better scalable one.

In the second article, I showed how to decouple the implementation of the state machine engine (for reuse) and the specific part (that can't be...]]> Tue, 07 May 2024 19:50:57 +0000 Massimiliano Pagani https://www.embeddedrelated.com/showarticle/1651.php Assertions are a simple tool you can use to enforce required conditions. Let's say you have a function that computes the square root of a number. Possibly nothing good would happen should this function be called with a negative argument. Maybe you even stated in the documentation for this function that it has to be called with a non-negative argument, but the program is running and ops, the...]]> Mon, 08 Apr 2024 16:37:36 +0000 Massimiliano Pagani https://www.embeddedrelated.com/showarticle/1628.php When the going gets tough, the tough get going. So, if you are going to deal with a problem slightly harder than switching a lightbulb on and off, you may want something better in your toolbox than what I described in my previous post on State Machines.

In this post, I'll start from the basic ad-hoc implementation presented in my last post and will decouple the state handling...]]> Thu, 14 Mar 2024 08:00:54 +0000 Massimiliano Pagani https://www.embeddedrelated.com/showarticle/1625.php Hardly you can find a concept so powerful yet so simple as the State Machine. It shouldn't come as a surprise that State Machines are so widespread, what may came as a surprise is how many bad implementations of this concept I found over the years.

In this post, I'll try to go through the basics, present a simple state machine, and evolve its design until you get a basic...]]> Mon, 05 Feb 2024 08:00:09 +0000 Massimiliano Pagani https://www.embeddedrelated.com/showarticle/1606.php Let's face it, handling errors is boring and hard. It is not a case that most introductory programming classes just glimpse over the matter and focus on other topics.  There are various approaches, but when you need to distinguish between the happy and the unhappy paths, no one is a clear winner. In this article, I will focus on Error Codes (a quite common way of reporting errors in...]]> Thu, 16 Nov 2023 07:19:28 +0000 Massimiliano Pagani