Page 65 - CITS - Electronic Mechanic - TT - 2024

ELECTRONICS MECHANIC - CITS

Embedded memory microcontroller − This type of microcontroller is designed in such a way that the
microcontroller has all programs and data memory, counters and timers, interrupts, I/O ports are embedded on
the chip. For example: Intel 8051 microcontroller.
Instruction Set
Based on the instruction set configuration, the microcontroller is further divided into two categories.
CISC − CISC stands for complex instruction set computer. It allows the user to insert a single instruction as an
alternative to many simple instructions.
RISC − RISC stands for Reduced Instruction Set Computers. It reduces the operational time by shortening the
clock cycle per instruction.

Difference between Microprocessor and Microcontroller

The following table highlights all the important differences between microprocessors and microcontrollers

Parameter Microprocessor Microcontroller
Definition Microprocessors can be understood Microcontrollers can be understood
as the heart of a computer system as the heart of an embedded system
What is it? A microprocessor is a processor A microcontroller is a controlling
where the memory and I/O device wherein the memory and
component are connected I/O output component are present
externally internally
Circuit complexity The circuit is complex due to Microcontrollers are present on chip
external connection memory. The circuit is less complex
Memory and I/O components The memory and I/O components The memory and I/O components
are to be connected externally are available
Compact system compatibility Microprocessors can’t be used in Microcontrollers can be used with a
compact systems compact system
Efficiency Microprocessors are not efficient Microcontrollers are efficient
Zero status flag Microprocessors have a zero-status Microcontroller doesn’t have a zero-
flag status flag
Zero status flag Microprocessors have a smaller Microcontrollers have a greater
number of registers number of registers
Applications Microprocessors are generally used Microcontrollers are generally
in personal computers used in washing machines, and air
conditioners wing

Introduction to 8051 Microcontroller

8051 microcontroller is designed by Intel in 1981. It is an 8-bit microcontroller. It is built with 40 pins DIP (dual
inline package), 4kb of ROM storage and 128 bytes of RAM storage, 2 16-bit timers. It consists of four parallel
8-bit ports, which are programmable as well as addressable as per the requirement. An on-chip crystal oscillator
is integrated in the microcontroller having crystal frequency of 12 MHz.

Features of 8051 MC

The main features of the 8051-microcontroller architecture include the following.
8-bit CPU through two Registers A & B.
8K Bytes – Internal ROM and it is a flash memory that supports while programming the system.

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CITS : E & H - Electronics Mechanic - Lesson 34 - 42