COMPUTER FUNDAMENTALS
Computer
An electronic device that processes input from users and produces useful information is called a computer. The term “computer” is derived from the Latin word “computare,” which means “to calculate” or “programmable machine.” A computer cannot perform any task without a program.
History of Computer
English mathematician Charles Babbage (1792-1871) invented the first mechanical computer.
First Generation Computer:
The first generation of computers was also known as Vacuum Tubes. Each machine was built, programmed, operated, and maintained by a single group of people. Programming was performed by connecting electrical circuits on plugboards with thousands of cables.
Second Generation Computer:
During the Second Generation of computers, they were commonly referred to as Transistors and Batch Systems. The computers manufactured in this era were reliable and were targeted towards customers such as government agencies and universities. Second-generation computers were extensively used for scientific and engineering purposes. Separate groups were formed to work on designing, building, and coding aspects of the computer.
Third Generation of Computers:
During the Third Generation of computers, Integrated Circuits (ICs) were introduced, and the concept of Multiprogramming became popular. Multiprogramming allowed for efficient utilization of the CPU by enabling another job to use it when one job was waiting for I/O to complete. Third Generation computers were used for performing large scientific calculations as well as for massive commercial data processing.
Fourth Generation Computers:
During the fourth generation of computers, they were commonly referred to as Personal Computers. Companies like Intel and IBM began developing operating systems for their respective CPUs. They also created user-friendly graphical user interfaces (GUI) for general-purpose usage. Network operating systems and distributed systems became popular in this era as well. In the network operating system, users were able to log in to remote machines and copy files from one machine to another.
Fifth Generation Computer:
Fifth generation of computers, also known as Mobile computers, were made using Ultra Large Scale Integrated Chips. This era saw the popularity of new operating systems such as Symbian, Blackberry OS, iOS, and Android. The devices became more portable and smaller in size. The use of Artificial Intelligence also became more prominent in this era, allowing for the creation of devices that used natural language processing for the analysis of input.
Booting process of the computer:
- When a computer is turned on, the process of loading its kernel is called booting.
- The computer’s parent board contains a program called BIOS (Basic Input Output System), which is responsible for checking the RAM, basic devices, and PCI buses as soon as the system is booted.
- The BIOS scans and checks the response of the devices. Once the initial check is done, BIOS starts the boot device from the hard disk.
- The first section of the boot device is read into the memory and executed.
- The secondary boot loader, which is present inside the sector, is also read into memory. Finally, the loader reads the operating system and starts it.
TYPES OF COMPUTERS
- ANALOG COMPUTER: Analog computers are computing devices that operate on continuous variables instead of digital ones. These devices were commonly used in scientific and engineering applications before the development of digital computers. Analog computers work by measuring and manipulating physical quantities such as voltage, current, and resistance, which correspond to the variables being computed.
- DIGITAL COMPUTER:The rise of digital computers has completely transformed the way humans process and store information. The binary number system serves as the backbone of modern digital computing, allowing users to easily represent data in a streamlined format.At the heart of every digital computer lies the central processing unit, or CPU. It is the CPU that serves as the computer’s “brain” and is responsible for performing all arithmetic and logical calculations on data stored in memory.
- MAINFRAME COMPUTER: A mainframe computer, by definition, is a highly sophisticated computing system that is renowned for its range of advanced capabilities, such as superior computing power, scalability, and top-notch security features. Mainframes are equipped with state-of-the art architecture that emphasizes not just computational speed and efficiency, but also a highly powerful central processing unit (CPU) and an immense amount of memory. they are also widely used in other high-stakes industries, including health care, telecommunications, and transportation, where failure-free operations are vital.
NUMBER SYSTEM
ANALOG SYSTEM: An analog system is a system that uses physical quantities to process and transmit continuous signals. They have been used in many fields like communication, control and instrumentation. In an analog system, the signals can vary continuously and can take any value within a range. This system uses analog circuits to make changes and amplify the signals. An advantage of analog systems is they keep the original features of the signal. However, they can be affected by noise and distortion, which can hurt the signal’s quality and precision. Even though digital systems have replaced analog systems in many areas, analog technology is still essential and continues to improve.
DIGITAL SYSTEM: Digital systems are a type of technology that uses bits to represent information. This is different from analog systems which use continuous signals. Digital systems can be found in computers and electronic devices because they can send and process information faster and more accurately. They are also able to store and process a lot of information. Because digital information can be changed without losing quality, they are more flexible than analog systems. But, digital systems are more complicated and need special knowledge to build and maintain.
OCTAL SYSTEM: Octal is a way of counting up to 8 using the digits 0-7. It’s useful in computer programming because it can be easily translated into binary code. For example, the octal number 246 is equal to the binary number 010 100 110. To turn an octal number into a decimal number, you multiply each digit by 8 to a power based on its position, then add them all together. For instance, the octal number 624 is equal to the decimal number 406.
HEXADECIMAL SYSTEM: Hexadecimal is a number system with 16 symbols that are used to represent numbers. It is often used in computer programming because it makes it easy to write big numbers in a short way. The symbols used are the numbers 0 to 9 and the letters A to F. Each symbol in a hexadecimal number stands for a power of 16, with the smallest symbol on the right. For example, the number “3A” means 3 lots of 16, plus 10 single units, which is the same as 58. People use hexadecimal numbers for things like showing colours on a computer screen with two symbols used to mean red, green, and blue and to represent addresses and other information in communication networks.
BINARY SYSTEM: Binary is a number system that uses only two numbers, 0 and 1, to represent numbers. Each digit in binary represents a power of two, with the rightmost digit representing 1, and each digit to the left representing double the previous digit. To turn binary into regular numbers, we multiply each digit by its corresponding power of two and add up the results. Binary is used in computers because computers use physical components that are either on or off. Binary is the foundation of digital systems, including computer hardware, software, and data. It’s the language that computers use when they talk to each other.
ASCII CODE
ASCII is a code that gives each letter and symbol a unique number. It uses 7 bits for each character, so there are 128 possible characters. ASCII includes letters, numbers, punctuation, and symbols. To find the ASCII code for a character, you can use a lookup table or tool. For example, the code for ‘A’ is 65, ‘a’ is 97, and ‘@’ is 64. ASCII is important for computer programming and communication. It helps computers process and exchange text. ASCII is still widely used today and helps different systems and applications work together.
ISCII CODE
ISCII (Indian Standard Code for Information Interchange) is a way to type Indian languages on computers. It was created in 1986 to make a standard for how the characters look. By using 8 numbers, it makes 256 different characters. There’s a table for each language that helps people type in several Indian scripts. Today, Unicode is a better way to type different languages, but some people still use ISCII.
EBCDIC CODE
EBCDIC(Extended Binary Coded Decimal Interchange Code) is a way to store letters, numbers, and symbols in computers and was designed by IBM in the 1960s. It can hold up to 256 different characters, including English letters, numbers, and special characters. EBCDIC was made so that computers could support different languages and is still used today, especially in big companies and the government who have been using it for a long time. Though it’s not used as much now due to high costs for upkeep, EBCDIC was an important part of computer history.
MORSE CODE
Morse code is a way to communicate that was made by Samuel Morse a long time ago. It uses dots and dashes for letters and numbers. This lets you send messages over far distances with telegraph wires or flashing lights. People can use different things to send and get Morse code messages now. Some people still use it for communication today, especially for something called amateur radio. Morse code is easy and works great, even in bad situations like war or bad weather. But, people don’t use it as much these days because we have newer and better ways to talk to each other.
HOLLERITH CODE
Hollerith code is a system of representing alphanumeric data in punched cards or paper tape using a combination of numbers, letters, and special characters. Developed by Herman Hollerith, it was widely used in the early computing industry for inputting and processing data.
In Hollerith code, each character is assigned a specific code or combination of codes. For example, the letter A is represented by the code 12, while the number 5 is represented by the code 25. The codes are punched into cards or tape using a special keypunch device, and the data is read and processed by a specialized computer.
While Hollerith code is now obsolete and has been replaced by more efficient and flexible data encoding systems, its impact on the development of computing cannot be overstated. It paved the way for more advanced data processing technologies and played a crucial role in shaping the modern computational landscape.
BINARY ADDITION
Binary addition is a way to add two numbers that use only the digits 0 and 1. To add them, you begin by adding the right-most digits. If their sum is less than 2, write it down. But if their sum is equal to or more than 2, write the remainder and carry the extra digit to the next column. You keep doing this until you have added all the columns. If you have a carry left at the end, write it on the left. For instance, if you add 1010 and 1101, you start at the right by adding 0 and 1, which makes 1. Then, you add 1,0, and 1 in the next column, which equal 10. You write 0 down, carry the one to the next column, etc. The result is 10111.
BINARY SUBTRACTION
Binary subtraction is a method used to subtract one binary number from another. It operates on the same principles as decimal subtraction, but using only 1’s and 0’s. To perform binary subtraction, the same rules for borrowing from the next column apply: when a 1 is subtracted from a 0, the 0 is changed to a 1, and the 1 in the next column is borrowed; when a 1 is subtracted from a 1, the result is 0; and when a 0 is subtracted from a 1, the result is 1. Sometimes, it may be necessary to add leading zeroes to the smaller number to make it the same length as the larger number. Binary subtraction is commonly used in computer programming and digital electronics, where binary arithmetic is a fundamental operation.
BOOLEAN THEOREM
Binary Boolean theorem is a type of math that deals with true or false statements. There are three main operations: AND, OR, and NOT. By using these, we can make more complicated statements. De Morgan’s Laws are another set of rules that show how to simplify these statements. This helps us understand them better. Truth tables show all the possible outcomes for different inputs. We use Boolean theorem in fields like computer science and electrical engineering.
HAPTIC TECHNOLOGY
Haptic technology uses touch to make digital experiences better. It can be found in phones, games, and virtual reality headsets. It makes things feel more real by giving users a physical feeling, like a phone vibrating when you get a message.Haptic technology is useful for doctors and patients too. For example, doctors can use it to control instruments better during surgery, and patients can use it to improve their movement.
ARITHMETIC CIRCUIT
An arithmetic circuit is a digital circuit that performs arithmetic operations on binary numbers. These circuits are fundamental components in digital computers and other electronic devices that involve numerical computations. Arithmetic circuits are designed to execute basic arithmetic operations such as addition, subtraction, multiplication, and division.
Key components of arithmetic circuits include:
Adders: Adders are circuits designed to perform addition. The basic building block is a half-adder, which adds two binary digits and produces a sum and a carry. Full adders can add three binary digits (two inputs and a carry from a previous stage), generating a sum and a carry.
Subtractors: Subtractors are circuits that perform subtraction. They can be implemented using a combination of adders and other logic gates. The subtraction operation involves adding the two’s complement of the subtrahend to the minuend.
Multipliers: Multipliers are circuits designed to perform multiplication. Various algorithms, such as the Booth’s algorithm, are used to implement efficient multiplication circuits. Multipliers take two binary numbers as input and produce their product.
Dividers: Dividers are circuits that perform division. Division is a more complex operation compared to addition and multiplication, and divider circuits can be relatively complex. Division is often implemented using iterative algorithms.
Accumulators: Accumulators are circuits that accumulate or sum a sequence of numbers. They are often used in applications such as digital signal processing and data processing.
Arithmetic circuits are crucial in the execution of mathematical operations within a digital system. Modern processors contain sophisticated arithmetic units that can perform a wide range of arithmetic and logic operations, contributing to the overall capability and performance of the computing system.
SEQUENTIAL CIRCUIT
Sequential circuits are a type of digital circuit in which the output not only depends on the present inputs but also on the past sequence of inputs. This means that the output of a sequential circuit is influenced by its current state, and it has some form of memory. One of the fundamental building blocks of sequential circuits is the flip-flop.
A flip-flop is a bistable multivibrator, which means it has two stable states. These states are often referred to as “0” and “1” or “reset” and “set.” The flip-flop can store a bit of information, and its output represents the current state of that stored bit.
There are various types of flip-flops, with the most common ones being:
SR Flip-Flop (Set-Reset Flip-Flop): The SR flip-flop has two inputs, Set (S) and Reset (R). It can be in one of two states: Set (Q=1, Q’ = 0) or Reset (Q=0, Q’ = 1). The inputs S and R are used to set or reset the flip-flop to one of these states.
D Flip-Flop (Data Flip-Flop): The D flip-flop, or data flip-flop, has a data input (D), a clock input (CLK), and outputs (Q and Q’). The output Q takes on the value of the input D at the moment when the clock signal transitions.
JK Flip-Flop: The JK flip-flop is similar to the SR flip-flop but includes a feedback mechanism. It has three inputs: J (set), K (reset), and a clock input (CLK). The behavior of the JK flip-flop is more versatile than that of the SR flip-flop, as it allows for toggling.
T Flip-Flop (Toggle Flip-Flop): The T flip-flop, or toggle flip-flop, has a single input (T) and a clock input (CLK). When the clock signal transitions, the output toggles (switches its state) if the T input is 1, and it remains unchanged if T is 0.
Flip-flops are used to store binary information and play a crucial role in the design of memory elements, registers, and other sequential logic circuits within digital systems like computers and microcontrollers. They provide a way to store and manipulate information over time in a controlled manner.