Presented by J.BHARATHI MCA 3rd SEM

• The embedded system is a combination of computer hardware, software additional electrical & mechanical parts

• A computer is used in such devices primarily as a means to simplify the system design and to provide flexibility.

• Embedded systems employ the use of a RTOS (Real-Time Operating System).

“ An embedded system can be defined as those control systems which are designed either by microprocessor or microcontroller for a specific tasks. ” OR“ An embedded system is some combination of computer hardware & software, either fixed in capability or programmable, that is specifically designed for a particular kind of application device. ”

Block Diagram of Block Diagram of Embedded SystemEmbedded System

COMPONENTS OF EMBEDDED SYSTEMHardware processorTimersInterrupt controllerI/O devicesMemories etc

CLASSIFICATION OF EMBEDDED SYSTEM The classification of embedded systems are

three types and they are Small scale embedded systems Medium scale embedded systems Sophisticated embedded systems

Small scale embedded systems:In the small scale embedded systems use

single 8bit or 16bit microcontrollersLittle hardware and software complexityUsually “C” is used for developing these

system

Medium scale embedded systems:In the medium scale embedded systems use

single or few 16 or 32bit microcontrollersTools RTOS,debugger

Sophisticated embedded system:In this EM use Enormous hardware and

software complexityWhich may need Scalable processor or

configurable processor and hardware units

Some other examples:

Physically, embedded systems range fromportable devices such as digital watches andMP3 players, to large stationary installationslike traffic lights, factory controllers, or thesystems controlling nuclear power plants.Complexity varies from low, with a singlemicrocontroller chip, to very high with multipleunits, peripherals and networks mounted insidea large chassis or enclosure.

Traffic LightDVD player

Digital clockMoving message display

• Computer design requirement

• System-level requirement

• Real time/reactive operation• Small size, low weight• Safe and reliable• Harsh environment• Cost sensitivity

• End product utility• System safety and reliability• Controlling physical systems• Power management

• CPU: Central Processing Unit• I/O: Input /Output• Bus: Address bus & Data bus• Memory: RAM & ROM• Timer• Interrupt

CPUGeneral-Purpose Micro-

processorRAM ROM I/O

PortTimer

Serial COM Port

Data Bus

Address Bus

General-Purpose Microprocessor System

• CPU for Computers• No RAM, ROM, I/O on CPU chip itself• Example--Intel’s x86: 8086,8088,80386,80486, Pentium

Many chips on mother board

General-purpose microprocessor

Microprocessor • CPU is stand-alone, RAM, ROM,

I/O, timer are separate• designer can decide on the

amount of ROM, RAM and I/O ports.

• expensive• general-purpose• Ex. 8085,8086 mp, Motorola

6800, Intel’s 8086, etc.

Microcontroller• CPU, RAM, ROM, I/O and

timer are all on a single chip• fix amount of on-chip ROM,

RAM, I/O ports• for applications in which cost,

power and space are critical• single-purpose• Ex. 8051, PIC mc, Motorola

MC’s, Phillips, etc.

Microprocessor v/s Microcontroller

The 8051 MicrocontrollerThe 8051 Microcontroller : :

• The 8051 is the first microcontroller of the MCS-51 family introduced by Intel Corporation at the end of the 1970’s.

• The 8051 family characteristics:

○ The 8051 family characteristics:○ 4K Bytes ROM○ 128 Bytes RAM○ two timer/counters (16 bit)○ A serial port○ 32 input/output port○ Interrupt controller

IC 8051 Daily ApplicationsIC 8051 Daily Applications

Moving message displayDigital clock

Traffic Light7 segment display

Applications

APPLICATIONS IN VARIOUS FIELDS

23%

11%

13%18%

9%

13%

10%3%

Source: ESP DEC 2002

23% - Communication18% - Electronics13% - Automobile13% - Aerospace11% - Industries10% - Military9% - Medical3% - Others

ADVANTAGES AND DISADVANTAGES EMBEDDED SYSTEMSDesign and Efficiency

The central processing core in embedded systems is generally less complicated, making it easier to maintain. The limited function required of embedded systems allows them to be designed to most efficiently perform their functions.

CostThe streamlined make-up of most embedded

systems allows their parts to be smaller less expensive to produce.

SCADE Model-based Code Gen Download Handbooks and White Papers

Accessibility

Embedded systems are difficult to service because they are inside another machine, so a greater effort is made to carefully develop them. However, if something does go wrong with certain embedded systems they can be too inaccessible to repair. This concern is sometimes addressed in the design stage, such as by programming an embedded system so that it will not affect related systems negatively when malfunctioning.

•Maintenance

Embedded systems are easier to maintain because the supplied power is embedded in the system and does not require remote maintenance.

RedundanciesEmbedded systems do not involve the

redundant programming and maintenance involved in other system models.

• More and more produced processors are used in embedded devices

• How would you like to live in a house that recognizes your fingerprints and opens the front door automatically?

• A fridge that checks your food supplies and places orders ; or intelligent lights and air conditioners that adjust their settings automatically according to the light and heat available at various times of the day.

What about a microwave oven that can send a message to your PDA saying that the cake you kept to bake is done? These are all possible in the near future.and the Blue tooth technology for communication. And they will also be connected to the Internet in most cases.

Think a mobile in the form of a ring or an earring? This can soon be a reality. IBM is already working on the prototype of a mobile phone that can be worn as jewellery. The components of the phone will be distributed among different pieces of jewellery like earring, necklace, ring and bracelet.

Smart card

ATM

Health card

Robotics

Conclusion A computer which is integrated into another system.

Embedded systems are part of a bigger system. In short an embedded system works for a predefined task. On the whole a hardware chip programmed for a dedicated task results in an embedded system. As integrated circuits get continuously cheaper, more capable and power efficient, complexity of chip designs are constantly growing. This is illustrated by new design approaches such as multi-core technologies. As there is no foreseeable end to this development of embedded system.