11-03-2011, 04:44 PM
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MICROCONTROLLER
What is a microprocessor?
The microprocessor is the integration of a number of useful functions.These functions are:
The ability to execute a stored set of instructions to carry out user defined tasks.
General-purpose microprocessor.
Act as CPU for Computers.
No RAM, ROM, I/O on CPU chip itself
Example Intel’s x86, Motorola’s 680x0
What is Microcontroller?
Microcontroller is a device which integrates a number of the components of a microprocessor system onto a single microchip.
So a microcontroller combines onto the same microchip :
The CPU core
Memory (both ROM and RAM)
Some parallel digital I/O
Microprocessor vs Micro-controllers
Microprocessors
High end of market where performance matters
High power dissipation–high cost
Need peripheral devices to work
Mostly used in microcomputers.
Microcontollers
Targeted for low end of market where performance does not matter
Low power dissipation –low cost
Memory plus I/O devices, all integrated into one chip
Mostly used in embedded systems
Embedded Systems
Embedded system means the processor is embedded into that application.
An embedded product uses a microprocessor or microcontroller to do one task only.
In an embedded system, there is only one application software that is typically burned into ROM.
Example printer, keyboard, video game player
Criteria in Choosing a Microcontroller
1. Meeting the computing needs of the task efficiently and cost effectively
Speed, the amount of ROM and RAM, the number of I/O ports and timers, size, packaging, power consumption
Cost per unit
2.Availability of software development tools
assemblers, debuggers, C compilers, emulator, simulator, technical support
3.Wide availability and reliable sources of the microcontrollers.
Introduction to Microcontroller
The microcontroller is a very common component in modern electronic systems. Its use is so widespread that it is almost impossible to work in electronics without coming across it.
Microcontroller are used in a wide number of electronic systems such as:
Engine management systems in automobiles.
Keyboard of a PC.
Electronic measurement instruments (such as digital multimeters, frequency synthesisers, and oscilloscopes)
Printers,Mobile phones.
Televisions, radios, CD players, tape recording equipment.