Book Image

Embedded Systems Architecture

By : Daniele Lacamera
Book Image

Embedded Systems Architecture

By: Daniele Lacamera

Overview of this book

Embedded systems are self-contained devices with a dedicated purpose. We come across a variety of fields of applications for embedded systems in industries such as automotive, telecommunications, healthcare and consumer electronics, just to name a few. Embedded Systems Architecture begins with a bird's eye view of embedded development and how it differs from the other systems that you may be familiar with. You will first be guided to set up an optimal development environment, then move on to software tools and methodologies to improve the work flow. You will explore the boot-up mechanisms and the memory management strategies typical of a real-time embedded system. Through the analysis of the programming interface of the reference microcontroller, you'll look at the implementation of the features and the device drivers. Next, you'll learn about the techniques used to reduce power consumption. Then you will be introduced to the technologies, protocols and security aspects related to integrating the system into IoT solutions. By the end of the book, you will have explored various aspects of embedded architecture, including task synchronization in a multi-threading environment, and the safety models adopted by modern real-time operating systems.
Table of Contents (18 chapters)
Title Page
Copyright and Credits
Packt Upsell

System resource separation

The example operating system built throughout this chapter already has many interesting features, but it is still characterized by a flat model, with no memory segmentation or privilege separation. Minimalist systems do not provide any mechanisms to separate system resources and regulate the access to the memory space. Instead, tasks in the system are allowed to perform any privileged operation, including reading and altering other tasks' memory, executing operations in the address space of the kernel, and directly access peripherals and CPU registers at runtime.

Different approaches are available on the target platform, aimed at increasing the level of safety on the system by introducing a limited number of modifications to the kernel in order to:

  • Implement kernel/process privilege separation
  • Integrate memory protection in the scheduler
  • Provide a system call interface through the supervisor call to access resources

Privilege levels

The Cortex-M CPU is designed to run...