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

Measuring power

The current in use by the target can be measured at any time by connecting an ammeter in series with the device. This mechanism, however, does not show all the oscillations of the values during a time interval, which is why it is often useful to sample the values of the parasitic voltage at the ends of a shunt resistor, using an oscilloscope.

A shunt resistor is placed in series with the target device, on either side of the power source. Its typical value is relatively small, in the range of a few ohms, to ensure that the parasit voltage stays low, but is still measurable by the oscilloscope:

Measuring current using an oscilloscope to sample the voltage applied to the shunt resistor

Due to the properties of a series circuit, the current running through the shunt is the same as the one used by the target system, so the voltage on the ends of the shunt resistor varies accordingly.

Development boards

In order to see the effects of the power optimizations, we must exclude the electronics...