SECTION A

1. What is the Block diagram of Computer explain in detail?

Mainly computing system consists of 3 components, that square measure central process unit (CPU), Input Devices, and Output Devices. The Central process Unit (CPU) is split into 2 components again: arithmetic logic unit (ALU) and also the management unit (CU). The set of instruction is within the sort of data.

A large quantity of knowledge is hold on within the storage device with the assistance of primary and storage device devices. The CPU is just like the heart/brain of the pc. The user doesn't get the required output, while not the required possibility taken by the CPU.  The Central process unit (CPU) is to blame for the process of all the directions that square measure given by the user to the pc system.

Fig: Block Diagram of the computer.

The data is entered through input devices like the keyboard, mouse, etc. This set of instruction is processed by the CPU when obtaining the input by the user, then the pc system produces the output. The pc will show the output with the assistance of output devices to the user, like  monitor, printer, etc.

•CPU (Central process Unit)

•Storage Unit

•ALU(Arithmetic Logic Unit)

•Control Unit

Central process Unit (CPU)

The computer system is nothing while not the Central process unit therefore, it's conjointly referred to as the brain or heat of pc. The CPU is AN electronic hardware device which might perform differing types of operations like arithmetic and logic operation.

The CPU contains 2 parts: the arithmetic logic unit and management unit. We've got mentioned in short the arithmetic unit, logical unit, and management unit that square measure given below:

Control Unit

The management unit (CU) controls all the activities or operations that square measure performed within the pc system. It receives directions or info directly from the most memory of the pc.

When the management unit receives AN instruction set or info, it converts the instruction set to regulate signals then; these signals square measure sent to the {central processor|central process unit|CPU|C.P.U.|processor|mainframe|electronicequipment|hardware|computer hardware} for any processing. The management unit understands that operation to execute, accurately, and within which order.

Arithmetic and Logical Unit

The arithmetic and logical unit is that the combinative  digital electronic circuit that may perform arithmetic operations on number binary numbers.It presents the arithmetic and logic operation. The outputs of ALU can amendment asynchronously in response to the input. The fundamental arithmetic and bitwise logic functions square measure supported by ALU.

Storage Unit

The information or set of tips square measure hold on within the storage unit of the pc system. The storage unit provides the house to store knowledge|theinfo|the information} or instruction of processed data. Knowledge} or data is saved or hold in storage device or memory device. The info storage is that the core perform and basic of the pc elements. 

Components of computing system

The hardware and computer code exist on the pc. The knowledge that is hold on through the device is understood as pc computer code. The hardware elements of the pc system square measure associated with electronic and mechanical components, and also the computer code part is said to information and pc programs. Several parts square measure connected to the most circuit card of the pc system referred to as a “motherboard.”

• Processor.
• Main Memory.
• Secondary Memory.
• Input Devices.
• Output Devices.

These square measure in the main 5 elements of the pc system. The pc hardware, pc computer code, and liveware exist within the part of the pc system.

Processor

The processor is an electrical electronic equipment at intervals the pc system. The Central process unit is that the CPU or main processor of the pc system. The processor carries out the directions of the pc program with the assistance of basic arithmetic and logic, input/output operations.

Main Memory 

The Random Access Memory is that the main memory of the pc system, that is understood as RAM. The most memory will store the software package computer code, application computer code, and different info.  The Ram is one in every of the quickest memory, and it permits the info to be decipherable and writeable.

Secondary memory

We will store the info and programs on a semipermanent basis within the secondary memory. The arduous disks and also the optical disks square measure the common secondary devices. It's slow and low-cost memory as compare to primary memory. This memory isn't connected to the processor directly.

It has an oversized capability to store the info. The magnetic disk contains a capability of five hundred gigabytes. The info and programs on the magnetic disk square measure organized into files, and also the file is that the assortment of knowledge on the disk. The storage device is direct access by the CPU; that’s why it's totally different from the first storage.

The magnetic disk is concerning a hundred times the capability of the most memory. The most distinction between primary and storage device is speed and capability. There square measure many giant blocks of knowledge that square measure traced from the magnetic disk into the most memory.

2.     What are input and output devices in the block diagram of computer?

Input Devices

The user provides the set of instruction or info to the pc system with the assistance of input devices like the keyboard, mouse, scanner, etc. knowledge|theinfo|the information} illustration to the pc system is within the sort of binary language at that time the processor processes the regenerate data. The input unit implements the info that is schooled by the user to the system.

We can enter the info from the skin world into the first storage because the input through input devices. The input devices square measure the medium of communication between the skin world and also the computing system. There square measure some necessary options of input devices that square measure given below:

1.      The input devices receive or settle for the info or instruction from the user, United Nations agency exists within the outside world.

2.These devices convert the info or instruction into the machine-readable type for any process.

3.The data input device performs just like the association between the skin world and our computing system.

4.The keyboard and mouse square measure common samples of input devices.

5.Once the complete procedure is finished, we tend to get the required output from the output devices

Output Devices

The output devices produce or generate the desired result according to our input, such as a printer, monitor, etc. These devices convert the data into a human-readable form from binary code.

The computer system is linked or connected to the outside world with the help of output devices. The primary examples of output devices are a printer, projector, etc. These devices have various features which are given below:

1. These devices receive or accept the data in the binary form.
2. The output devices convert the binary code into the human-readable form.
3. These devices produce the converted result and show to the user.

3.     Explain Random Access Memory  in computer system

RAM (Random Access Memory) is that the internal memory of the CPU for storing information, program, and program result. It's a read/write memory that stores information till the machine is functioning. As before long because the machine is transitioned, information is erased.

Access time in RAM is freelance of the address, that is, every storage location within the memory is as simple to achieve as different locations and takes a similar quantity of your time. Information within the RAM may be accessed indiscriminately however it's terribly big-ticket.

RAM is volatile, i.e. information hold on in it's lost after we turn out the pc or if there's an influence failure. Hence, a backup Uninterruptible power grid (UPS) is commonly used with computers. RAM is little, each in terms of its physical size and within the quantity of knowledge it will hold.

RAM is of 2 varieties varieties

•Static RAM (SRAM)

•Dynamic RAM (DRAM)

Static RAM (SRAM)

The word static indicates that the memory retains its contents as long as power is being provided. However, information is lost once the facility gets down because of volatile nature. SRAM chips use a matrix of 6-transistors and no capacitors. Transistors don't need power to forestall leak, therefore SRAM needn't be rested on a daily basis.

There is further house within the matrix, thus SRAM uses additional chips than DRAM for a similar quantity of space for storing, creating the producing prices higher. SRAM is so used as cache memory and has in no time access.

Characteristic of Static RAM

•Long life

•No ought to refresh

•Faster

•Used as cache memory

•Large size

•Expensive

•High power consumption

Dynamic RAM (DRAM)

DRAM, not like SRAM, should be frequently rested so as to take care of the info. This is often done by inserting the memory on a refresh circuit that rewrites the info many hundred times per second. DRAM is employed for many system memory because it is affordable and little. All DRAMs square measure created of memory cells, that square measure composed of 1 capacitance and one semiconductor.

Characteristics of Dynamic RAM

•Short information period of time

•Needs to be rested ceaselessly

•Slower as compared to SRAM

•Used as RAM

•Smaller in size

•Less big-ticket

•Less power consumption

4.     Explain Read Only Memory in computer system

ROM stands for browse solely Memory. The memory from that we will solely browse however cannot pen it. This sort of memory is non-volatile. The knowledge is hold on for good in such reminiscences throughout manufacture. A store stores such directions that square measure needed to begin a pc. This operation is remarked as bootstrap. Store chips aren't solely employed in the pc however conjointly in different electronic things like washer and kitchen appliance.

Let us now discuss the various types of ROMs and their characteristics.

MROM (Masked ROM)

The terribly initial ROMs were hard-wired devices that contained a pre-programmed set of knowledge or directions. These reasonably ROMs square measure called covert ROMs, that square measure cheap.

PROM (Programmable browse solely Memory)

PROM is fixed storage which will be changed just once by a user. The user buys a blank promenade and enters the required contents employing a promenade program. Within the promenade chip, there square measure little fuses that square measure burnt open throughout programming. It may be programmed just once and isn't effaceable.

EPROM (Erasable and Programmable browse solely Memory)

EPROM may be erased by exposing it to ultra-violet light-weight for a length of up to forty minutes. Usually, AN ROM implement achieves this operate. Throughout programming, AN electrical charge is treed in AN insulated gate region. The charge is preserved for quite ten years as a result of the charge has no leak path. For erasing this charge, ultra-violet light-weight is capable a quartz window (lid). This exposure to ultra-violet light-weight dissipates the charge. Throughout traditional use, the quartz lid is sealed with a sticker.

EEPROM (Electrically effaceable and Programmable browse solely Memory)

EEPROM is programmed and erased electrically. It may be erased and reprogrammed concerning 10 thousand-fold. Each erasing and programming take concerning four to ten ms (millisecond). In EEPROM, any location may be by selection erased and programmed. EEPROMs may be erased one computer memory unit at a time, instead of erasing the whole chip. Hence, the method of reprogramming is versatile however slow.

Advantages of store

The advantages of store square measure as follows −

•Non-volatile in nature

•Cannot be accidentally modified

•Cheaper than RAMs

•Easy to check

•More reliable than RAMs

•Static and don't need refreshing

•Contents square measure perpetually renowned and might be verified

5.     What are the Secondary Storage Devices in computer system?

You know that processor memory, additionally called primary memory, is dear likewise as restricted. The quicker primary memory are volatile. If we want to store great deal of knowledge or programs for good, we want a less expensive and permanent memory. Such memory is named secondary memory. Here we are going to discuss secondary memory devices which will be wont to store great deal of knowledge, audio, video and multimedia system files.

Characteristics of Secondary Memory

These area unit some characteristics of secondary memory, that distinguish it from primary memory −

•It is non-volatile, i.e. it retains knowledge once power is shifted

•It is massive capacities to the tune of terabytes

•It is cheaper as compared to primary memory

Depending on whether or not secondary storage device is a component of C.P.U. Or not, there area unit 2 kinds of secondary memory – fastened and removable.

Let us look at some of the secondary memory devices available.

Hard Disk Drive

Hard disk drive is formed from a series of circular disks known as platters organized one over the opposite nearly ½ inches apart around a spindle. Disks area unit fabricated from non-magnetic material like aluminium alloy and coated with 10-20 nm of magnetic material.

Standard diameter of those disks is fourteen inches and that they rotate with speeds variable from 4200 rev (rotations per minute) for private computers to 15000 rev for servers. Knowledge is keep by magnetizing or demagnetizing the magnetic coating. A magnetic browseer arm is employed to read knowledge from and write knowledge to the disks. A typical fashionable HDD has capability in terabytes (TB).

CD Drive

CD stands for optical disk. CDs area unit circular disks that use optical rays, sometimes lasers, to browse and write knowledge. They're all-time low as you'll get 700 MB of space for storing for fewer than a dollar. CDs area unit inserted in CD drives designed into C.P.U. Cupboard. They're moveable as you'll eject the drive, take away the CD and carry it with you. There area unit 3 kinds of kinds of

•CD-ROM (Compact Disk – browse solely Memory) − the info on these CDs area unit recorded by the manufacturer. Proprietary software package, audio or video area unit free on CD-ROMs.

•CD-WO (Compact Disk – Recordable) − knowledge is written by the user once on the CD-R. It can not be deleted or changed later.

•CD-RW (Compact Disk – Rewritable) − knowledge is written and deleted on these optical disks once more and once more.

DVD Drive

DVD stands for Digital computer screen. Videodisk area unit optical devices which will store fifteen times the info control by CDs. They're sometimes wont to store made multimedia system files that require high storage capability. DVDs additionally are available in 3 varieties – browse solely, recordable and rewritable.

Pen Drive

Pen drive may be a moveable storage device that uses solid state memory instead of magnetic fields or lasers to record knowledge. It uses a technology kind of like RAM, except that it's nonvolatile .it's additionally known as USB drive, key drive or nonvolatile storage.

Blu Ray Disk

Blu Ray Disk (BD) is associate optical storage media wont to store high definition (HD) video and alternative multimedia system filed. Bachelor's degree uses shorter wavelength optical device as compared to CD/DVD. This allows arm to focus additional tightly on the disk and thus pack in additional knowledge. BDs will store up to 128 GB knowledge.

6.     Define Machine-level language

The machine-level language could be a language that consists of a collection of directions that square measure within the binary kind zero or one. As we all know that computers will perceive solely machine directions, that square measure in binary digits, i.e., 0 and 1, that the directions given to the pc will be solely in binary codes. Making a program terribly} machine-level language could be a very tough task because it isn't simple for the programmers to put in writing the program in machine directions. It's fallible because it isn't simple to grasp, and its maintenance is additionally terribly high. A machine-level language isn't moveable as every laptop has its machine directions, therefore if we have a tendency to write a program in one laptop can now not be valid in another laptop.

The totally different processor architectures use different machine codes, for instance, a PowerPC processor contains reduced instruction set computer|architecture} architecture, which needs totally different code than intel x86 processor, that incorporates a CISC design.

6.     Define Assembly Language

The programming language contains some human-readable commands like mov, add, sub, etc. the issues that we have a tendency to were facing in machine-level language square measure reduced to some extent by victimisation associate degree extended type of machine-level language referred to as programming language. Since programming language directions square measure written in English words like mov, add, sub, therefore it's easier to put in writing and perceive.

As we all know that computers will solely perceive the machine-level directions, therefore we have a tendency to need a translator that converts the assembly code into machine language. The translator used for translating the code is thought as associate degree assembly program.

The programming language code isn't moveable as a result of the info is keep in laptop registers, and also the laptop needs to grasp the various sets of registers.

The assembly code isn't quicker than machine language as a result of the programming language comes higher than the machine language within the hierarchy, therefore it means programming language has some abstraction from the hardware whereas machine language has zero abstraction.

7.     Differences between Machine-Level language and Assembly language

The following are the differences between machine-level language and assembly language:

8.     Define High-Level Language

The problem-oriented language could be a artificial language that permits a software engineer to write down the programs that ar freelance of a specific style of laptop. The high-level languages ar thought of as high-level as a result of they're nearer to human languages than machine-level languages.

When writing a program in a very problem-oriented language, then the entire attention has to be paid to the logic of the matter.

A compiler is needed to translate a problem-oriented language into a low-level language.

Advantages of a problem-oriented language

•The problem-oriented language is simple to scan, write, and maintain because it is written in English like words.

•The high-level languages ar designed to beat the limitation of low-level language, i.e., movableness. The problem-oriented language is portable; i.e., these languages ar machine-independent.

9.     Differences between Low-Level language and High-Level language

The following are the differences between low-level language and high-level language:

10. What are the File Directories?

A single directory may or may not contain multiple files. It can also have sub-directories inside the main directory. Information about files is maintained by Directories. In Windows OS, it is called folders.

Following is the information which is maintained in a directory:

• Name The name which is displayed to the user.
• Type: Type of the directory.
• Position: Current next-read/write pointers.
• Location: Location on the device where the file header is stored.
• Size : Number of bytes, block, and words in the file.
• Protection: Access control on read/write/execute/delete.
• Usage: Time of creation, access, modification

File types- name, extension

Summary:

• A file is a collection of correlated information which is recorded on secondary or non-volatile storage like magnetic disks, optical disks, and tapes.
• It provides I/O support for a variety of storage device types.
• Files are stored on disk or other storage and do not disappear when a user logs off.
• A File Structure needs to be predefined format in such a way that an operating system understands it.
• File type refers to the ability of the operating system to differentiate different types of files like text files, binary, and source files.
• Create find space on disk and make an entry in the directory.
• Indexed Sequential Access method is based on simple sequential access
• In Sequential Access method records are accessed in a certain pre-defined sequence
• The random access method is also called direct random access
• Three types of space allocation methods are:
  • Linked Allocation
  • Indexed Allocation
  • Contiguous Allocation
• Information about files is maintained by Directories