0TOPICS TO BE DISCUSSED
- System
- Embedded System
- Components
- Classifications
- Processors
- Other Hardware
- Software
INTRODUCTION:
What is a system?,
A system is a way of working, organizing or doing one or many tasks according to a fixed plan, program or set of rules.
A system is also an arrangement in which all its units assemble and work together according to the plan or program.
SYSTEM EXAMPLES
WATCH
It is a time display SYSTEM
Parts: Hardware, Needles, Battery, Dial,
Chassis and Strap
Rules
1.All needles move clockwise only
2.A thin needle rotates every second
3.A long needle rotates every minute
4.A short needle rotates every hour
5.All needles return to the original position after 12 hours
WASHING MACHINE
It is an automatic clothes washing SYSTEM
Parts: Status display panel, Switches & Dials, Motor, Power supply & control unit, Inner water level sensor and solenoid valve.
Rules
1.Wash by spinning
2. Rinse
3. Drying
4.Wash over by blinking
5. Each step display the process stage
6. In case interruption, execute only the remaining.
EMBEDDED SYSTEM DEF
Definition: An Embedded System is one that has computer hardware with software embedded in it as one of its important components.
Its software embeds in ROM (Read Only Memory). It does not need secondary memories as in a computer.
Components of computer hardware:
A Microprocessor
A Large Memory (Primary and Secondary) (RAM, ROM and caches)
Input Units (Keyboard, Mouse, Scanner, etc.)
Output Units (Monitor, printer, etc.)
Networking Units (Ethernet Card, Drivers, etc.)
I/O Units (Modem, Fax or Modem, etc.)
COMPONENTS OF EMBEDDED SYSTEM:
1). It has Hardware:
Processor, Timers, Interrupt controller, I/O Devices, Memories, Ports, etc.
2). It has main Application Software:
Which may perform concurrently the series of tasks or multiple tasks.
3). It has Real Time Operating System (RTOS):
RTOS defines the way the system work. Which supervise the application software. It sets the rules during the execution of the application program. A small scale embedded system may not need an RTOS.
EMBEDDED SYSTEM CONSTRAINTS
An embedded system is software designed to keep in view three constraints:
1. Available system memory
2. Available processor speed –The need to limit the power dissipation
When running the system continuously in cycles of wait for events, run, stop and wakeup.
What makes embedded systems different?
- Real-time operation
- size
- cost
- time
- reliability
- safety
- energy
- security.
VARIOUS PROCESSOR:
1. General Purpose processor (GPP):
Microprocessor, Microcontroller, Embedded Processor, Digital signal Processor
2. Application Specific System Processor (ASSP)
3. Multi Processor System using GPPs.
EMBEDDED PROCESSOR:
- Special microprocessors & microcontrollers often called, Embedded processors.
- An embedded processor is used when fast processing fast context-switching & atomic ALU operations are needed.
Examples : ARM 7, INTEL i960, AMD 29050.
APPLICATION SPECIFIC SYSTEM PROCESSOR (ASSP):
- ASSP is dedicated to specific tasks and provides a faster solution.
- An ASSP is used as an additional processing unit for running the application in place of using embedded software.
Examples : IIM7100, W3100A.
MULTI PROCESSOR SYSTEM USING GPPs:
- Multiple processors are used when a single processor does not meet the needs of different task.
- The operations of all the processors are synchronized to obtain an optimum performance.
APPLICATIONS:
- Household appliances: Microwave ovens, Television, DVD Players & Recorders
- Audio players
- Integrated systems in aircrafts and missiles
- Cellular telephones
- Electric and Electronic Motor controllers
- Engine controllers in automobiles
- Calculators
- Medical equipments
- Videogames
- Digital musical instruments, etc.
