Book Image

Hands-On RTOS with Microcontrollers

By : Brian Amos
Book Image

Hands-On RTOS with Microcontrollers

By: Brian Amos

Overview of this book

A real-time operating system (RTOS) is used to develop systems that respond to events within strict timelines. Real-time embedded systems have applications in various industries, from automotive and aerospace through to laboratory test equipment and consumer electronics. These systems provide consistent and reliable timing and are designed to run without intervention for years. This microcontrollers book starts by introducing you to the concept of RTOS and compares some other alternative methods for achieving real-time performance. Once you've understood the fundamentals, such as tasks, queues, mutexes, and semaphores, you'll learn what to look for when selecting a microcontroller and development environment. By working through examples that use an STM32F7 Nucleo board, the STM32CubeIDE, and SEGGER debug tools, including SEGGER J-Link, Ozone, and SystemView, you'll gain an understanding of preemptive scheduling policies and task communication. The book will then help you develop highly efficient low-level drivers and analyze their real-time performance and CPU utilization. Finally, you'll cover tips for troubleshooting and be able to take your new-found skills to the next level. By the end of this book, you'll have built on your embedded system skills and will be able to create real-time systems using microcontrollers and FreeRTOS.
Table of Contents (24 chapters)
1
Section 1: Introduction and RTOS Concepts
5
Section 2: Toolchain Setup
9
Section 3: RTOS Application Examples
13
Section 4: Advanced RTOS Techniques

Intertask Communication

Now that we're able to create tasks, it's time to start passing data between them. After all, you don't often run into systems that have a bunch of parallel tasks operating completely independently of one another; normally, you will need to pass some data between different tasks in the system. This is where intertask communication comes into play.

In FreeRTOS, intertask communication can be achieved using queues and direct task notifications. In this chapter, we'll cover a few different use cases for queues using examples and discuss the pros and cons of each. We will look at all of the details regarding tasks that block while waiting for an item to appear in the queue, as well as timeouts. Once we have looked at queues, we'll move on to task notifications and learn why we should use them and when.

In a nutshell, we will be covering...