Module 3 Introduction to Embedded systems Definition Embedded

Module 3 Introduction to Embedded systems

Definition: Embedded system: It is an electronic/electro-mechanical system designed to perform a specific function and is combination of both hardware and firmware (software). The program instructions written for embedded systems are referred to as firmware, and are stored in Read-Only-Memory or Flash memory

Embedded system vs General computing system General purpose computing system Embedded system • It is a combination of generic hardware and general purpose os • Contains general purpose os. • Application are programmable by user. • Performance is key deciding factor in selection. • Less tailored towards power requirements. • Response requirements are not time-critial • Need not be deterministic • • It is a combination of special purpose hardware and embedded os. May or may not contain os. It is pre-programmed and non-altered by user. Application specific requirements are key deciding factors. Highly tailored towards power saving. Response requirements are time –critial in some systems. For certain systems behaviour is deterministic.

Classification of Embedded Systems: Embedded systems are classified based on following criteria's: • On generation • On complexity & performance

Classification based on generation • Based on generation embedded systems can be classified as • First generation(1 G): 8 -bit μp and 4 -bit μc. • Second generation(2 G): 16 -bit μp and 8 -bit μc. • Third generation(3 G): 32 -bit μp & 16 -bit μc. • Fourth generation(4 G): 64 -bit μp & 32 -bit μc.

Classification based on Complexity and performance Embedded systems can be classified as Small-scale • Simple applications where the performance requirements are not time-critical. • Built around low performance and low cost 8 or 16 bit μp/μc. Medium-scale • Slightly complex in hardware and firmware requirement. • Built around medium performance and low cost 16 or 32 bit μp/μc. Large-scale • Highly complex hardware & firmware. • Built around 32 or 64 bit RISC μp/μc or PLDs or So. C or multi-core processors.

Purpose of Embedded System • • • Data Collection/Storage/Representation Data communication Data processing Monitoring Control Application specific user interface

Applications of Embedded Systems Embedded systems play a vital role in our day to day life from home to industry. Its applications are countless. A few of important domains and products are as listed : • Household appliances • Automotive industry • Home automation & security systems • Telecom • Computer peripherals • Computer networking systems • Healthcare

Conti. . • • Banking & Retail Card Readers Measurements & Instrumentation Missiles and Satellites Robotics Motor control systems Entertainment systems Signal & Image processing

Elements of an embedded system Microprocessor/ controller Communication interface