Microprocessor:- Microprocessor is a controlling unit of a micro-computer, fabricated on a small chip capable of performing ALU (Arithmetic Logical Unit) operations and communicating with the other devices connected to it.
Microprocessor consists of an ALU, register array, and a control unit. ALU performs arithmetical and logical operations on the data received from the memory or an input device. Register array consists of registers identified by letters like B, C, D, E, H, L and accumulator. The control unit controls the flow of data and instructions within the computer.
How does a Microprocessor Work?
The microprocessor follows a sequence: Fetch, Decode, and then Execute.
Initially, the instructions are stored in the memory in a sequential order. The microprocessor fetches those instructions from the memory, then decodes it and executes those instructions till STOP instruction is reached. Later, it sends the result in binary to the output port. Between these processes, the register stores the temporarily data and ALU performs the computing functions.
List of Terms Used in a Microprocessor
Here is a list of some of the frequently used terms in a microprocessor −
Instruction Set − It is the set of instructions that the microprocessor can understand.
Bandwidth − It is the number of bits processed in a single instruction.
Clock Speed − It determines the number of operations per second the processor can perform. It is expressed in megahertz (MHz) or gigahertz (GHz).It is also known as Clock Rate.
Word Length − It depends upon the width of internal data bus, registers, ALU, etc. An 8-bit microprocessor can process 8-bit data at a time. The word length ranges from 4 bits to 64 bits depending upon the type of the microcomputer.
Data Types − The microprocessor has multiple data type formats like binary, BCD, ASCII, signed and unsigned numbers.
Features of a Microprocessor
Here is a list of some of the most prominent features of any microprocessor −
Cost-effective − The microprocessor chips are available at low prices and results its low cost.
Size − The microprocessor is of small size chip, hence is portable.
Low Power Consumption − Microprocessors are manufactured by using metaloxide semiconductor technology, which has low power consumption.
Versatility − The microprocessors are versatile as we can use the same chip in a number of applications by configuring the software program.
Reliability − The failure rate of an IC in microprocessors is very low, hence it is reliable.
CPU:- A CPU (central processing unit) is the part of a computer that executes instructions. This can be implemented using a single IC, a number of ICs, discrete transistors or a room full of vacuum tubes.
A microprocessor is a single-chip implementation of a CPU.
Nowadays pretty much all CPUs for general use are microprocessors, causing the two terms to be practically synonymous.
A Central Procession Unit (CPU) is the part of a computer that sequences and executes instructions. Other parts in the traditional computer architecture are the memory and the I/O.
In the stone age days of computers a mainframe's CPU's occupied multiple cabinets. Later a minicomputer's CPU occupied one or a few PCBs. The next step was to integrate a CPU on a single chip. That is what we call a microprocessor (uP).
From there the development forks:
the CPU-on-a-chip is made more powerfull (faster, parallel execution, fast execution of complex instructions like divide and transcendentals), a cache is added, more CPU's are combined in one chip, etc. This results in the (mainly Intel) super-microprocessors of today.
a moderately powerfull CPU (more powerfull than those in a uC, but less than those in a desktop CPU) is combined with a small boot ROM and a set of complex peripherals, like a video/lcd subsystem, mpeg decoder, wired or wireless ethernet interface, USB intefaces, etc. to cerate a 'system-on-a-chip'. These chips form the hart of modern set-top boxes and the small Linux systems (Beaglebone, Raspberry Pi, etc.) derived from them.
The CPU is combined with memory and I/O on the same chip, creating a complete computer on a single chip. This is called a microcontroller (uC).
