What this book covers
Chapter 1, Embedded Systems – A Pragmatic Approach, is an introduction to microcontroller-based embedded systems. The scope of the book is identified, from a broader definition of “embedded systems” to the actual domain that will be analyzed – 32-bit microcontrollers with physical memory mapping.
Chapter 2, Work Environment and Workflow Optimization, outlines the tools used and the development workflow. This is an introduction to the toolchain, debuggers, and emulators that can be used to produce code in a binary format that can be uploaded and run on the target platform.
Chapter 3, Architectural Patterns, is all about the strategies and development methodologies for collaborative development and testing. This chapter proposes a description of the processes that are typically used while developing and testing software for embedded systems.
Chapter 4, The Boot-Up Procedure, analyzes the boot phase of an embedded system, boot stages, and bootloaders. It contains a detailed description of the bring-up code and the mechanisms used to separate the software into several boot stages.
Chapter 5, Memory Management, suggests some optimal strategies for memory management by pointing out common pitfalls and explaining how to avoid memory errors that can result in unpredictable or bad behavior in the application code.
Chapter 6, General-Purpose Peripherals, walks through accessing GPIO pins and other generic integrated peripherals. This is the first interaction of the target platform with the outside world, using electric signals to perform simple input/output operations.
Chapter 7, Local Bus Interfaces, guides you through the integration of serial bus controllers (UART, SPI, and I2C). A code-oriented, detailed analysis of the most common bus communication protocols is introduced by explaining the code required to interact with the transceivers commonly available in embedded systems.
Chapter 8, Power Management and Energy Saving, explores the techniques available to reduce power consumption in energy-efficient systems. Designing low-power and ultra-low-power embedded systems requires specific steps to be performed for reducing energy consumption while running the required tasks.
Chapter 9, Distributed Systems and IoT Architecture, introduces the available protocols and interfaces required to build distributed and connected systems. IoT systems need to communicate with remote endpoints using standard network protocols that are implemented using third-party libraries. Particular attention is dedicated to securing communication between endpoints using secure sockets.
Chapter 10, Parallel Tasks and Scheduling, explains the infrastructure of a multitasking operating system through the implementation of a real-time task scheduler. This chapter proposes three approaches for implementing operating systems for microcontrollers from scratch, using different schedulers (cooperative, pre-emptive, and safe).
Chapter 11, Trusted Execution Environment, describes the TEE mechanisms typically available on embedded systems and provides an example of running secure and non-secure domains using ARM TrustZone-M. On modern microcontrollers, TEE provides the opportunity to secure specific areas of memory or peripherals by limiting their access from the non-secure execution domain.