ADVANCE EMBEDDED SYSTEM DESIGN

INTRODUCTION TO EMBEDDED SYSTEMWhat is an embedded system??An embedded system is an electronic/electro-mechanical system designed to perform a specific function and is a combination of both hardware and firmware (software).Unique.h/w as well as firmware is highly specialized to the application domain.

Embedded systems vs General computing systemsEmbedded SystemGeneral Purpose Computing SystemA system which is a combination of special purpose h/w and embedded OS for executing a specific set of applications.May or may not contain OS for functioning.The firmware of the embedded system is pre-programmed and it is non alterable by the end user.

A system which is a combination of a generic h/w and a General Purpose Operating System for executing a variety of applications.Contains General Purpose Operating System (GPOS).Application are alterable by the user(Programmable).Application specific requirements(like performance, power requirements, memory usage,etc) are the key deciding factors.Response time requirement is highly critical.Execution behavior is deterministic for certain types of ES like hard real time systemsPerformance is the key deciding factor in the selection of the system.

Response requirement are not time critical.

Need not to be deterministic in execution behavior.

HistoryOlden days-embedded systems was developed in low level languages.Advance in semiconductor, nano technology and IT revolution.Apollo Guidance Computer(AGC)-MIT Instrumentation Laboratory lunar expedition.Astronauts communicated with the AGC using a numeric display andkeyboardcalled theDSKY(DiSplay&KeYboard, pronounced 'DISS-key').

The first mass-produced embedded system was the guidance computer for the Minuteman -I missile -'Autonetics D-17' guidance computer, built using discrete transistor logic and a hard-disk for main memory

CLASSIFICATION OF ES1. Based on generation2. Complexity & performance requirements3. Based on deterministic behavior- RTOS-> hard and soft4. Based on triggering-Reactive in nature-.event triggered or time triggered.81. CLASSIFICATION BASED ON GENERATIONFirst generation : 8 bit p like 8085 & 4 bit c - simple h/w f/w in assembly code.Stepper motor, digital telephonic keypads

Second generation : 16 bit p and 8/16 bit c instruction set much more complex and powerful.Data acquisition systems,SCADA systems.

Third generation : 32 bit p and 16 bit c DSP and ASIC came to picture pipelining evolved Robtics,media,industrial process control, n/wing.

Fourth generation : 64 bit p and 32 bit c. advent of SOC,reconfigurable, multi core processors- making use of high performance RTES.Smart phones devices.

2. CLASSIFICATION BASED ON COMPLEXITY AND PERFORMANCESmall scale embedded system:SimpleNot time criticalLow performanceLow cost(8 or 16 bit mp or mc)May or may not contain o.smedium scale embedded system:Slight complex in h/w and s/wMedium performanceLow cost(16 or 32 bit mp or mc)Usually contain an o.sLarge scale embedded system :Highly complex h/w and s/wDemanding high performance(32 or 64 bit RISC mp or mc-RSoC)May contain multi-core processors and co processorsUsually contain RTOS for task scheduling and prioritization management.Response is time critical.MAJOR APPLICATION AREASConsumer electronicsHouse hold appliancesSecurity systemsAutomotive industryTelecomComputer networking systemsHealthcareMeasurement and instrumentationBanking & retailCard readersPURPOSE OF EMBEDDED SYSTEMSEach embedded system is designed to serve the purpose of any one or a combination of the following tasks:

Data collection/storage/representationData communicationData processingMonitoring ControlApplication specific user interface