A Comprehensive Guide on Embedded Systems Architecture

 

The concept of embedded systems originates from the simple idea of merging software and hardware systems. Further, their usage, applications, and structure play a major role here. Breaking down the term ‘embedded,’ ‘systems,’ and ‘architecture’ will help you to understand the concept better. However, it becomes crucial to state that the idea of a system is at its core. 

 

Concept of Systems, Embedded Systems, and Embedded Systems Architecture

System

A system objectively denotes an assembly of many units that follow a set of rules. Thus, it is safe to say that system is an arrangement of units that help perform different types of work according to a fixed plan. For example, the design of a Personal Computer works as per the planned directions given to it. If you perform a task on the system, you can predict the output because all the system's components are interdependent. 

 

Embedded Systems

An Embedded System consists of multiple layers of components that can specifically work according to the set rules. Yet, it is essential to note that it can either be an independent system governed by the task given or be a part of a more extensive system to perform per the later ones. Generally, there are two primary components of embedded systems. But, a large-scale embedded system can have up to three layers of components. 

• The Fundamental Hardware Layer - forms the base for the other two layers in the system.
• The Application software Layer - adds the essential software to be processed.
• The RTOS in Embedded System Layer (Real-Time Operating System Layer aka Alertness Software Layer) - for more supervision applications governing the rules. 

Embedded systems are based on microprocessing or micro-controlling. It can perform tasks independently or inside much bigger systems. Therefore, they have to be highly reliable throughout the process. This separates a system and an embedded system making the latter a microprocessor-based, advanced software-driven, real-time control system. 

Embedded Systems Architecture - Components of Embedded System

On the other hand, the embedded system's architecture refers to the system's architectural design. It allows any person (technical or non-technical) to understand its quality and performance. The architecture lays out the codes and components of the embedded system to the person studying the system. Thus, it becomes easy for them to define and improve per the requirements. 

Furthermore, understanding the functionality and testing can only be put forward after the architecture is clearly in front of you. Every component has a purpose, and learning every aspect of it will be quite a task without the embedded architectures. So, to further examine the system for changes and add new elements, it becomes crucial to have the architecture out in the open.

 

Characteristics of Embedded Systems

The task specificity highly governs how the embedded systems will turn out. Thus, the software layer is the one that engineers program to resolve specific needs. These characteristics can define the basics for you.

 

Single-Task Oriented

The most common practice of the embedded system is working according to a specific task. Therefore, it repeatedly functions according to the rules set around the particular job. 

 

Low Needs - Hight Performance

As the basis lies in the idea of microprocessors and microcontrollers, the power consumption, size, and cost must be low. However, it needs to perform its processes much more quickly (real-time) at a limited power usage for better battery life. Efficiency is an essential feature of this software-driven system.

 

Memory Usage

These microprocessors have a ROM of their own, implying there is no need for any secondary memory in the computer for the system to work. Hence, the ROM is also embedded in the system as a hardware component.

 

Consistency

The microprocessor-based systems are highly reliable, efficient, and stable in their work. The hardware provides flexibility, making it a consistent solution for many processes today.

 

Connections

There have to be connections of peripherals. It allows input and output device connections.

 

User Interface

An embedded system has many types of user interfaces (UI). There can be no interface in some cases, while, in others, it can have highly complex graphical interfaces. Depending upon the needs of the task, there can be necessary tweaks and modifications in the UI.

 

Embedded Systems Architecture Types

 

 

The types of embedded systems architecture differ in the code and data placements. Accordingly, there are two types of architecture used in general. 

 

Von Neumann Architecture

In this architecture, the case data and the code for the software and hardware performing tasks are in one single memory block. According to John Von Neumann, the architecture uses a single path (or bus) for data and instructions for the central processing unit. Therefore, the CPU can perform one specific task at a given time. It is either the instruction fetching or data operation. 

Simple Hardware is at the core of this embedded systems architecture. The microprocessor is fast and massively used today because of the small amount of memory (cache) that is local to the processor. One sequential memory and a single operation path make the process less complex.

 

Harvard Architecture

Differentiating this embedded systems architecture from the former ones is the separate storage and signal paths for data and instructions. It can simultaneously fetch data and perform programs as the memory spaces are different for both. It cannot boot itself; there is a need for an operator for Harvard Architecture. 

The two sections of memories can be completely different in their composition. They don’t have to share properties as processes are taking place independently of each other.

 

Difference between Von-Neumann and Harvard Embedded Systems Architecture

The essential need for embedded systems remains the same. But, their formation and output performance differ much.

 

Von-Neumann Architecture	Harvard Architecture
The processes' instructions and the information registry are within the same memory bounds.	Independent spaces for the code of the architecture and the data bank.
The processes happen in quick succession due to the quick recalling of data, resulting in low power consumption.	The speed is much slower, causing higher power consumption for the processes.
As one memory works on a specific task simultaneously, one process requires two clock cycles for completion.	The simultaneous happening of data exchange and instruction performance, hence, one clock cycle to complete the task.
Based on a simple hardware design.	Based on Complex Embedded System Design.

 

Conclusion

While closing it in, this comprehensive guide will provide a quick insight into the basic understanding of embedded systems, their designs, requirements of embedded systems and their architecture. It will specifically prove beneficial for you to understand the reliability of microprocessor-based systems. Moreover, the two types of embedded systems architecture will help you to get to the application of these reliable systems quickly.