Book Image

Embedded Systems Architecture - Second Edition

By : Daniele Lacamera
5 (1)
Book Image

Embedded Systems Architecture - Second Edition

5 (1)
By: Daniele Lacamera

Overview of this book

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. This book will help you get the hang of the internal working of various components in real-world systems. You’ll start by setting up a development environment and then move on to the core system architectural concepts, exploring system designs, boot-up mechanisms, and memory management. As you progress through the topics, you’ll explore the programming interface and device drivers to establish communication via TCP/IP and take measures to increase the security of IoT solutions. Finally, you’ll be introduced to multithreaded operating systems through the development of a scheduler and the use of hardware-assisted trusted execution mechanisms. With the help of this book, you will gain the confidence to work with embedded systems at an architectural level and become familiar with various aspects of embedded software development on microcontrollers—such as memory management, multithreading, and RTOS—an approach oriented to memory isolation.
Table of Contents (18 chapters)
Part 1 – Introduction to Embedded Systems Development
Part 2 – Core System Architecture
Part 3 – Device Drivers and Communication Interfaces
Part 4 – Multithreading

The memory protection unit

In a system without virtual address mapping, it is harder to create a separation between sections that can be accessed by the software at runtime. The memory protection unit, often referred to as the MPU, is an optional component present in many ARM-based microcontrollers. The MPU is used to separate sections in memory by setting local permissions and attributes. This mechanism has several uses in real-life scenarios, such as preventing access to memory when the CPU is running in user mode, or preventing fetching code from being executed from writable locations in RAM. When the MPU is enabled, it enforces the rules by triggering a memory exception interrupt when those rules are violated.

While commonly used by operating systems to create process stack separation and enforce privileged access to system memory, the MPU can be useful in a number of other cases, including bare-metal applications.

MPU configuration registers

In the Cortex-M, the control...