22-02-2011, 04:09 PM
presented by:
Hala Siraj Y
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EMBEDED SYSTEMS
INTRODUCTION
WHAT IS EMBEDDED SYSTEM?
An Embedded System is a microprocessor based system that is embedded as a subsystem, in a larger system. (which may or may not be a computer system).
It is embedded as part of a complete device often including hardware and mechanical parts.
An embedded system is a computer system designed to perform one or a few dedicated functions often with real-time computing constraints.
The embedded system is dedicated to specific tasks.
CATEGORIES OF EMBEDDED SYSTEMS
REAL TIME EMBEDDED SYSTEMS
• Hard Real Time Systems
• Soft Real Time Systems
NETWORKED APPLIANCES
MOBILE DEVICES
HARDWARE FUNDAMENTALS
• Embedded Systems does not have
Key-board,Mouse, HDD,CD/DVD Drive,Monitor
• Embedded systems have
A Few LEDs,LCD Display Screen,Push buttons
Two separate memory for Data & Programme.
Microprocessor / DSP
Sensors
Converters (A-D and D-A)
Actuators
Memory
Design Issues(Hardware-Software Co-design)
System Specification
Functions, Real Time Constraints, Cost and Power Constraints
Hardware Software Partitioning
Allocating the tasks into hardware, software running on custom hw or general purpose hardware
Hardware Synthesis
Software Synthesis and Code Generation
Scheduling – allocation of time steps for several modules sharing the same resource
Implementation
PROGRAMMING LANGUAGES
Machine level Languages
Not much Used
Time Consuming
Assembly level Languages
Suitable for small scale applications
High level languages
‘C’,’C++’,JAVA
‘C’ IS PREFERABLE.
The C programming language is perhaps the most popular programming language for programming embedded systems.
Coding standards IN EMBEDDED SYSTEMS
Common aims
Reliability
Portability
Maintainability
Testability
Reusability
Extensibility
Readability
Connection With The Externel device
Serial Communication Interfaces (SCI): RS-232, RS-422, RS-485 etc.
Synchronous Serial Communication Interface: I2C, SPI, SSC and ESSI (Enhanced Synchronous Serial Interface)
Universal Serial Bus (USB)
Multi Media Cards (SD Cards, Compact Flash etc.)
Networks: Ethernet, Controller Area Network, Lon Works, etc.
Timers: PLL(s), Capture/Compare and Time Processing Units
Discrete IO: aka General Purpose Input/Output (GPIO)
Analog to Digital/Digital to Analog (ADC/DAC)
Applications of Embedded Systems
Automotive electronics
Aircraft electronics
Trains
Telecommunication
Medical systems
Military Appliences
MORE USES
Assembly line quality monitors
Bar code readers
Bread machines
Cameras
Car assembly robots
Cell phones
Centrifuge controllers
CD players
Disk drive controllers
“Smart card” processors
Fuel injector controls
Medical equipment monitors
PDAs
Printer controllers
Sound systems
Rice cookers
Telephone switches
Water pump controllers
Welding machines
Windmills
• Wrist watches