Principles of Computing

Principles of Computing

any computer needs two things to work with:

1. Hardware

2. Software

Hardware - Computer machines and parts are called hardware. Hardware is the physical structure of the computer. In fact, all the things we can see and touch come under hardware. Such as System Unit, Monitor, Printer, Keyboard, Mouse, Memory Device etc.

Software - Hardware cannot edit any task itself Must be instructed to the hardware to edit any task. This work is done by software.

Working principle of computer

the functioning of the computer is generally divided into five parts which are required for all types of computers:

(i) Input - The act of inserting data and instructions (Data and Instructions) into a computer is called input. It is completed by the input unit.

(ii) Storage - Data and instructions are stored in the memory unit so that they can be used as per requirement Intermediate and Final results.

(iii) Processing - The data received by the input is converted into information by arithmetic and logical calculations (Arithmetic and Logical Operations) as per instructions and the desired tasks are carried out.

(iv) Output - The task of displaying information or results to the user after processing by the computer is called output. It is completed by the output unit.

(v) Control - Controlling and coordinating tools, instructions and information used in various processes.

Main components of computer

the internal structure of the computer may vary from computer to computer, but depending on the methodology, they can be divided into the following parts:

1. Input Unit

2. Storage Unit or Memory

3. System Unit

    a) Mother board

    b) Central Processing Unit (CPU)

    c) Primary or Main Memory

4. Output Unit

Input Device

Electrical mechanical (Electromechanical) device used to insert data, programs, instructions (Instructions) and instructions (Commands) into the computer is called input device. The input unit receives data and instructions from the user and converts it into digital form and submits it for processing. Since the computer can only understand binary signals (0 and 1 or on and off), all input devices convert data and instructions into binary signals with the help of input interface (Input interface).

the functions of the input device are as follows:

1. accepting data, instructions and programs.

2. convert them into binary codes.

3. to give the changed code to the computer system.

Some examples of input devices are Keyboard, Mouse, Joystick, Lightpen, Scanner, Barcode reader, MICR, Punchcard Reader

Storage Unit or Memory

data and instructions are placed in memory before processing. the interim and final results obtained by the process are also kept in memory.

thus memory protects -

1. data and instructions given for process

2. Intermediate results

3. Final results

memory which is mainly divided into two parts:

(i) Primary or Main Memory - It is electronic memory located inside the computer system unit. Its memory capacity is low while the speed is fast. It stores temporary instructions and immediate results. It is a temporary (Volatile) memory in which the information is also lost when the computer is turned off. Data and instructions are temporarily placed in primary memory just before processing. The interim results and output received are stored in primary memory before displaying. Semiconductor Register, Cache, ROM and RAM are examples of primary memory. These are made up of registers or cache memory within CPU or microprocessors, while ROM and RAM are on the motherboard. CPU is directly related to cash memory.

(ii) Secondary or Auxiliary Memory - Data, software and end results are permanently stored in auxiliary memory. Data is brought from auxiliary memory to the main memory before the data process is brought by the computer process. Auxiliary memory has the ability to store huge data at a lower cost. It is a permanent (Non-volatile) memory in which data is not lost even when the computer is turned off or electricity is not available. Magnetic disk, Optical disk, Harddisk etc. are examples of auxiliary memory.

Registers - It is a very high speed primary memory built with CPU or microprocess. It is also known as the executive memory of the CPU. CPU is able to processing the data in the register. Therefore, data and instructions are transferred to the register before processing. The Access time of register memory can be 1-2 nano seconds.

Cache Memory - Cache memory is directly connected to CPU, so the computer motherboard system bus does not have to be used to access data from cache memory to CPU. Therefore, the speed of data transfer is faster. CPU first looks for cache memory for the desired information. If the desired information is not found in the cache memory, it will be RAM/out. It is searched in ROM. Cache memory acts as a buffer between CPU and main memory. Cache memory is extremely fast memory but it is more expensive. The Access time of cache memory can be up to 2-10 nano seconds.

RAM - RAM is a semiconductor memory chip mounted in a memory slot on the motherboard. It is a temporary (Volatile) primary memory in which access time of data does not depend on the physical state of the data. Hence, its speed is fast. During processing, data and instructions are brought from the assistant and stored in the RAM. CPU receives them from RAM and processes data. An interim or final result is permanently stored in RAM.

ROM - ROM semiconductor is a memory chip installed by a computer manufacturing company on a computer motherboard. ROM is a permanent (Non-Volatile) primary memory in which the stored data is neither destroyed nor replaced. Software required to start the computer is stored in ROM.

CMOS Chip - Some information and settings in the computer are constantly changing but the computer has to keep updating them. Even if a personal computer is turned on after some time or a few days, it tells us the exact time and day of the present. Such information is stored in CMOS chip memory. CMOS chip memory is a semiconductor memory installed on the computer motherboard with a button-shaped battery, which keeps CMOS memory working even when the computer is off.

System Unit

The system unit of a personal computer is its main hardware. The system unit is like a box. All hardware systems in the computer are located in the unit except input and output devices. The system unit consists mainly of power supply units, motherboards, CPU or Microprocessor, Main memory and many ports.

1. Motherboard - Motherboard is the main circuit board of a computer. The entire computer revolves around the motherboard. The motherboard is equipped with equipment like CPU, ROM, RAM Memory etc. Other computer devices such as Input unit, Output Unit, Harddisk Drive, Sound card, Video card etc. are connected to motherboards and in future Expansion slots are also made on the motherboard to connect hardware devices.

2. Computer Bus - A group of conductor wires on the motherboard that moves computer data and signals from one place to another within the computer system is called a computer bus. Instructions and information are exchanged between CPU and other hardware and peripheral devices of the computer system through bus route.

Internal / System Bus - Data and signals are exchanged between devices on the motherboard by internal or system bus. It has a fast pace of data transfer. The system is simply divided into three parts - Data bus, Address bus and Control bus.

External / Expansion Bus - External or Expansion bus computer connects peripheral devices such as Keyboard, Mouse, Monitor, Printer, Harddisk, CD Drive etc. to the motherboard. It has a relatively slow pace of data transfer.

3. CPU or Microprocessor - CPU is also known as the brain (Brain of Computer) of a computer, it controls, directs and coordinates all computer functions (Control, Supervise and Co-ordinate). The CPU also does the job of processing the data as directed. CPU is actually a dense IC Chip also known as microprocessors. Works on the basis of CPU stored program instructions. Before processing, data and instructions are temporarily stored in a register made in CPU CPU performs arithmetic and logical actions (Mathematical and Logical Operations) for data processing as per the instructions in the register. All data processing works are carried out by CPU.

THE MAIN FUNCTIONS OF CPU ARE:

1. to determine the order of various procedures.

2. controlling and directing various computer devices.

3. coordination between computer hardware and software.

4. processing of input data as directed.

CPU CAN BE DIVIDED INTO THREE MAIN PARTS IN TERMS OF HARDWARE:

1. Control Unit

2. Arithmatic logic unit

3. Memory register

1. Control Unit - The control unit of the CPU controls all the functions of the computer and coordinates between software and hardware The control unit has a list of tasks that can be performed by CPU called instruction set Control Unit is called Computer Pulse System (Nerve system).

the main functions of the control unit are:

1. control input and output devices and other hardware.

2. Controlling the functions of Arithmatic logic unit.

3. to bring data from the main memory and store them immediately.

4. to read and order the instructions to be implemented.

5. to coordinate between hardware and software.

2. Arithmatic Logic Unit - ALU is a part of cpu. Data processing is done only by actual low ALU it performs all kinds of mathematical and logical actions as per the instructions received from the control unit on data. ALU is again divided into two parts - AU (Arithmatic Unit) and LU (Logic Unit). AU performs arithmetic calculations on data such as addition, subtraction, multiplication, division, etc. on the other hand, LU performs logical functions on data (Logical Operations) such as - large (Greater Than), small (Less Than), equal (Equal to) etc. thus ALU performs arithmetic calculations and comparisons on data.

3. Memory register - Register are made inside the CPU and are called executive memory of CPU. CPU can only processing the data in the register. The higher the number and size of the register in the CPU, the faster the processing speed of the CPU.

Output Unit

output device is a device used by the computer to convey the interim results obtained after processing to the user. and displays the results obtained by the processer in a user's understandable form. since the results from the process are in binary signals (0 or 1). hence, they are converted into normal signals by the output interface.

output device functions -

1. obtaining results from cpu.

2. convert the results obtained into signals that can be understood by humans.

3. convey the changed signals of the result to the user.

There are some examples of output devices - Monitor, Printer, Plotter, Speaker, Projector, Card reader etc.

BIOS (Basic Input Output System)

BIOS is a software program which is stored in a permanent ROM memory chip by the motherboard manufacturing company and installed on the computer motherboard. When the computer is turned on, the software is first run BIOS BIOS examines the software associated with the computer called POST (Power on self test). The boot strap loader (Boot strap loader) program located BIOS checks the operating system and orders it to be put in the main memory. Pressing the Delete button (DEL Key) when the computer is on opens BIOS Setup where we can change the BIOS as per the options given.

FACTORS AFFECTING THE SPEED OF CPU

The efficiency of the CPU or microprocessor is measured based on the number of instructions that can be edited in a second. Since the CPU edits millions of instructions in a second. Its speed in measured in MIPS or BIPS.

factors affecting the speed of cpu are:

1. System Clock - The speed of processing cpu data depends on the electronic clock inside the computer called system clock. Data processing is divided into several small and basic stages. Clock pulses are generated by the system clock Clearly, the faster the clock pulse generates the system clock pulse, the faster the speed of cpu's data process. The speed of the system clock is measured based on the number of clock pulses produced in a second. The number of pulses produced in a second is called hertz (Hertz - Hz). The speed of the system clock is generally denoted in mega hertz (MHz) or ghz (GHz). In computers available nowadays, the speed of the system clock can be from 500 MHz to 4 GHz.

2. Memory register - Register are made inside the CPU and are called executive memory of CPU. CPU can only processing the data in the register. The higher the number and size of the register in the CPU, the faster the processing speed of the CPU.

3. Word Length - The word range is the number of binary digits that the computer takes for processing at once. The speed of the computer increases when the word range is high. The length of the word range can be up to 8,16,32 or 64 bits. The 64 bit word range means that the computer can prosse 64 bit data simultaneously.

4. Cache Memory - Cache memory is directly connected to CPU, so the computer motherboard system bus does not have to be used to access data from cache memory to CPU. Therefore, the speed of data transfer is faster. CPU first looks for cache memory for the desired information. If the desired information is not found in the cache memory, it will be RAM/out. It is searched in ROM. Cache memory acts as a buffer between CPU and main memory. Cache memory is extremely fast memory but it is more expensive. The Access time of cache memory can be up to 2-10 nano seconds.

5. System Bus - If the width of the system bus built in the computer is 32 bits, then it means that there are 32 wires in the computer bus. This means that the processor can simultaneously exchange 32 bits of data.

6. Parallel Operation - Simultaneous implementation of several instructions leads to better utilization of cpu capacity which increases the speed of the computer Dual core or multicore Processor two or more processes are made simultaneously on the same chip. It uses Parallel processing which increases the efficiency of cpu.

6. Integration between CPU and Peripherals - Generally, CPU calculates faster, so slow motion of other equipment affects the speed of the computer.

Measuring the performance of a computer system

Throughput - The number of useful processing edited by the computer per unit time is called throughput. More throughput indicates better efficiency but also depends on the work that is processed.

Response time - In Multi tasking operating system, the computer devotes a little time to processing all the tasks. The time between the computer being given the processing work and the first response to the CPU to edit the work is called Response time. Response time should be less for better efficiency.

Turn around time - The time between giving the computer the work for processing and the computer completing it and giving final results is called Turn around time. Turn around time should be less for better efficiency.