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

FreeRTOS Memory Management

So far, we've worked through many examples of creating FreeRTOS primitives; however, when these primitives were initially created, there wasn't much of an explanation as to where the memory was coming from. In this chapter, we'll learn exactly where the memory comes from, along with when and how it is allocated. Choosing when and how memory is allocated allows us to make trade-offs between coding convenience, timing determinism, potential regulatory requirements, and code standards. We'll conclude by looking at different measures that can be taken to ensure application robustness.

In a nutshell, this chapter covers the following:

  • Understanding memory allocation
  • Static and dynamic allocation of FreeRTOS primitives
  • Comparing FreeRTOS heap implementations
  • Replacing malloc and free
  • Implementing FreeRTOS memory hooks
  • Using a memory protection...