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
Contributors
Preface
Index

System time


Timekeeping is a basic requirement for almost any embedded system. A microcontroller can be programmed to trigger an interrupt at regular intervals, which is commonly used to increment the monotonic system clock. To do so, a few configuration steps must be performed at startup in order to have a stable tick interrupt. Many processors can run at custom frequencies while using the same oscillator as source. The input frequency of the oscillator, which can be internal or external to the CPU, is used to derive the processor main clock. The configurable logic integrated in the CPU is implemented by a PLL that multiplies the input clock from an external stable source, and produces the desired frequencies used by the CPU and integrated peripherals.

Adjusting the flash wait states

If the initialization code is running from flash, it might be necessary to set the wait state for the flash memory before altering the system clocks. If the microprocessor runs at high frequencies, it might require...