Introduction to Embedded Systems A combination of hardware and software which together form a component of a larger machine. An embedded system is designed to run on its own without human intervention, and may be required to respond to events in real time. An embedded system is designed to perform a dedicated function.
Characteristics of an Embedded SystemsReal-Time Operation• Reactive: computations must occur in response to external events• Correctness is partially a function of timeSmall Size, Low Weight• Hand- held electronics and Transportation applications -- weight costs moneyLow Power• Battery power for 8+ hours (laptops often last only 2 hours)Harsh environment• Heat, vibration, shock, power fluctuations, RF interference, lightning, corrosionSafety- critical operation• Must function correctly and Must not function in correctlyExtreme cost sensitivity• $. 05 adds up over 1,000, 000 units
555 Timer The 555 timer IC is an integrated circuit (chip) used in a variety of timer, pulse generation, and oscillator applications. The 555 can be used to provide time delays, as an oscillator, and as a flip- flop element.
The wide spectrum of embedded systemdevices is that there is no singledefinition reflecting them all. Automotive: Ignition System, Engine Control, Brake System Industrial Control: Robotics and Control Systems Networking: Routers, Hubs Office Automation: Fax Machine, Printers, Scanners
Embedded Systems Design When approaching embedded systems architecture design, several models can be applied to describe the cycle of embedded system design. The big-bang model: there is essentially no planning or processes in place before and during the development of a system. The code-and-fix model: product requirements are defined but no formal processes are in place before the start of development. The waterfall model: there is a process for developing a system in steps, where results of one step flow into the next step. The spiral model: there is a process for developing a system in steps, and throughout the various steps, feedback is obtained and incorporated back into the process.
The embedded system design and development process is divided into four phases: creating the architecture, implementing the architecture, testing the system, and maintaining the system. Creating Architecture is defined as being made up of six stages: ◦ having a strong technical foundation (stage 1), ◦ understanding the Architectural Business Cycle (stage 2), ◦ defining the architectural patterns and models (stage 3), ◦ defining the architectural structures (stage 4), ◦ documenting the architecture (stage 5), and ◦ analyzing and reviewing the architecture (stage 6).
The Embedded Systems Model What the Embedded Systems Model indicates is that all embedded systems share one simi-larity at the highest level; that is, they all have at least one layer (hardware) or all layers (hardware, system software and application software) into which all components fall. The hardware layer contains all the major physical components located on an embedded board, whereas the system and application software layers contain all of the software located on and being processed by the embedded system.
Application Areas Medical Systems ◦ Pace maker, Patient Monitoring Systems, Injection Systems, Intensive Care Units(ICU), … Office Equipment ◦ Printer, Copier, Fax, … Tools ◦ Multimeter, Oscilloscope, Line Tester, GPS, … Banking ◦ ATMs, Statement Printers, … Transportation ◦ (Planes/Trains/[Automobiles] and Boats) RADAR, Traffic Lights, Signalling Systems, …
Application Areas• TV• Stereo• Remote Control• Phone / Mobile Phone• Refrigerator• Microwave• Washing Machine• Electric Tooth Brush• Oven / Rice or Bread Cooker• Watch• Alarm Clock• Electronic Musical Instruments• Electronic Toys(Stuffed Animals, Handheld Toys, Pinballs, etc.)• Medical Home Equipment (e.g. Blood Pressure, Thermometer)
An embedded system is an applied computer system. “Embedded System", it constantly evolves with advances in technology and dramatic decreases in the cost of implementing various hardware and software components. Widely used in industries.