Microcontroller

Microcontroller

• A Microcontroller is a small computer on a single integrated circuit containing electronic computing unit and logic unit (combinedly known as CPU), Memory (Program Memory and Data Memory), I/O ports and few other components integrated on a single chip.
• Microcontroller is like a mini computer with a CPU along with RAM, ROM, serial ports, timers, and IO peripherals all embedded on a single chip.

• Bus width
• Memory Structure
• Instruction set
• Number of input/output Pins

• Bus width indicates the size of the data bus. Higher bus widths often result in better performance.
• Microcontrollers come in 8bit, 16 bit, 32 bit and 64 bit. Some most advanced microcontroller have bits more than 64 which are capable of executing particular functions in the embedded system.
• Based on bit configuration, the microcontroller is further divided into following categories.
  • 8-bit Microcontroller
  • 16-bit Microcontroller
  • 32 –bit Microcontroller

• Microcontrollers need memory (RAM, ROM, EPROM, EEPROM, Flash memory ,etc) to store programs and data.
• Based on the memory configuration, the microcontroller is further divided into two types :
  • Embedded Memory Microcontroller
  • External Memory Microcontroller

• Based on the instruction set configuration, the microcontrollers is classification into two categories CISC or RISC.
• CISC : CISC stand for complex instruction set computer. It allows the user to insert a single instruction as alternative to many simple instruction.
• RISC : RISC stands for Reduced Instruction Set Computers. It reduces the operational time by shortening the clock cycle per instruction.

• Microcontrollers vary according to the number of input-output pin sizes.
• One can choose a specific microcontrollers  as per the requirement of application.

• CPU
• Memory
• Input/output ports
• System Bus
• Timers and Counters
• Serial Ports
• Interrupt Control
• ADC (Analog to Digital Converter)
• DAC (Digital to Analog Converter)

• Microcontroller 8051
• AVR Microcontroller
• PIC Microcontroller
• ARM Microcontroller
• Renesas Microcontroller

• 8051 microcontrollers  is an 8-bit family of microcontroller and is developed by the intel in the year 1981.
• This is one of the popular families of microcontroller being used all across the world.
• It has 128 byte of on chip RAM.
• The data memory can be expanded up to 64kb.
• It is a CISC based Microcontroller with Harvard Architecture (separate program and data memory).

• AVR Microcontroller was developed in the year of 1996 by Atmel Corporation.
• The structural design of AVR was developed by the Alf-Egil Bogen and Vegard Wollan.
• The AVR microcontroller are modified Harvard RISC architecture with separate memory for data and program.
• The speed of AVR is high when compare to 8051 and PIC.
• The AVR stand for Alf-Egil Bogen and Vegard Wollen’s RISC processor.

• Peripheral Interface Controller (PIC) is microcontroller developed by a Microchip.
• PIC microcontroller is fast and simple to implement program when you compare other microcontrollers like 8051.
• It Controlled by the software.
• It is RISC based Design 
• Its Code os extremely efficient, allowing the PIC to run with typically less program memory than its larger competitors.
• It is low cost, high clock speed.

• The ARM microcontroller stands for Advance Risk Machine.
• It is one of the extensive and most licensed processor cores in the world.
• The first ARM microcontroller was developed in the year 1978 by Cambridge University.
• The ARM RISC processor was produced by Acorn Group of Computers in the year 1985.
• ARM processors are widely used in customer electronic devices such as smart phones, tablets, multimedia players and other mobile devices such as wearable.

Renesas Microcontroller 

• Renesas is latest automotive Microcontroller family that offers high performance feature with exceptionally low power consumption over a wide and versatile extend of item.
• This microcontroller  offers rich functional security and embedded safety characteristics required for new and advanced automotive application..

• An embedded System is a combination of Hardware and Software.
• An embedded system can be an independent system or it can be a part of large system.
• It is a microcontroller or microprocessor based on system which is designed to perform a specific task.
• It is more of an application oriented system i.e. it is dedicated to perform a single task.
• For example Fire alarm is embedded system; it will sense only smoke.

• Processor
• Memory
• Peripherals
• Software