Lecture 2: Hardware (39 slides)

1. Lecture 2: Hardware (39 slides) Information technology Lecturer: Prof. Anatoly Sachenko

2. Lecture Overview • Central Processing Unit • Memory • Input Devices • Output Devices • Input/Output Devices • Storage Devices

3. Central Processing Unit • Central processing unit(CPU) is a basic component of computer • It’s running the arithmetic and Boolean operations, program , controlling a computational process, and co-ordinating work of all computer devices • CPU contains: • ALU • CU • Data bus and addresses bus • Registers • Programs counter (continued on next slide)

4. Central Processing Unit (continued) • Cache — very rapid memory of small volume (8-1024 Kb) • Mathematical co-processor for the floating point numbers • ALU- is that one part of processor where the commands are running • CU - is another part of processor running the controlling functions • Registers - a row of the specialised additional memory cells • Trigger - the basic element of register is an electronic chart, which is able to keep one binary number (digit of binary code)

5. Central Processing Unit (continued) • Modern processors are executed as microprocessors • Physically a microprocessor is the integrated circuit — thin rectangular form crystalline silicon lamina by an area only a few square millimeters where the blocks are placed on realizing all processor’s functions • Part of its digits is used for operation code storing, other — for storage of the operands addresses codes • Register types: • Adder is a register of ALU partaking in each operation running ( see next slide) (

6. Central Processing Unit (continued) • Command counter is the CU register which corresponds to an address of next running instruction • It serves for the automatic selection of the program from successive memory cells • Command register is the CU register for command code storing on the period of time, necessary for its completion • Microprocessor is a programmable digital electronic component that incorporates the CPU functions on a single semiconducting integrated circuit (next slide)

7. Central Processing Unit (continued) • One or more microprocessors typically serve as the CPU in a computer system, embedded system, or handheld device

8. Memory – How it Builds? • Computer memory consists of the binary storage elements — bits, incorporated in groups for 8 bits which are named bytes • All bytes are numbered • The number of byte is named as its address • Bytes can be united in cells which are named also words • For each computer a certain word capacity is fixed as the two, four or eight bytes (continued in the next slide)

9. Memory – How it Builds? (continued) • It does not eliminate the use of memory of other length cells (for example, half-word, double word) • One integer or one command can be presented in one computer word • The variable formats of information presentation are assumed • Breaking up of memory on words for four-byte computers is presented in a table below: Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 HALFWORDHALFWORD HALFWORD HALFWORD WORD WORD DOUBLE WORD

10. Memory - RAM • RAM (Random Access Memory) is a rapid data storage with not large volume • It is direct-coupled with a processor and intended for a writing, reading and storing of the programs and processed data • This memory is used for the temporal storage of data and programs only because all data in RAM disappear when a machine is turned off • There is a direct access toa RAM, it means that each memory byte has own individual address • Usual capacity is 32…512 Mb

11. Memory - RAM (continued) • RAM is implemented in a semiconductor storage • It takes the form of integrated circuits • It allows the stored data to be accessed in any order — that is, at random and without the physical movement of the storage medium or a physical reading head • Key benefit of RAM over types of storage which require physical movement is that retrieval times are short and consistent • Short because no physical movement is necessary (continued on the next slide)

12. Memory - RAM (continued) • Consistent because the time taken to retrieve a piece of data does not depend on its current distance from a physical head • It requires practically the same amount of time to access any piece of data stored in a RAM chip

13. Memory - Cache • Cache or scratchpad memory is a very rapid memory of small volume • It is used for an exchange information between a microprocessor and main memory for difference indemnification in speed of information processing by processor and by less fast-acting main memory • Cache-memory is managed by Controller • It analyses a running program trying to foresee what information and commands are needed to the processor in the nearest time

14. Memory- Cache & Special Memory(Continued) • Cache-memory is implemented by the microcircuits of static memory of SRAM (Static RAM) • It’s characterized by faster performance and less capacity than Dynamic RAM(DRAM ) or synchronous RAM (SDRAM) • Read Only Memory (ROM) is a memory for reading only • It depends on power supply, and it’s used for storage data that will never demand a change • Its content is "sewn" upspecially into a device during its manufacturing for permanent storage

15. Memory - Special Memory (continued) • It is mainly used to distribute firmware - software that is tied very closely to a specific hardware • Modern semiconductor ROM chips are not immediately distinguishable from similar chips like RAM modules • RAM chips can be read faster than most ROMs • Writing speed is always much slower than reading speed • Flash Memory is a memory that depends on power supply and assumes the frequent rewriting • It’s included a BIOS (Basic Input/Output System)

16. Memory - Special Memory (continued) • BIOS (Basic Input/Output System) is an aggregate of the programs intended for the automatic devices testing after plugging computer and OS loading into main memory • CMOS RAMis the memory with a low fast-acting and minimum energy consumption • It is used for data storage about computer equipment configuration as well as its mode of operation • Video memory (VRAM) is a variety of RAM, where the coded images are saved • It is organised so, that its content is accessible at once to two devices: processor and display

17. Input devices • Input device is a hardware mechanism that transforms data into external world for consumption by a computer • A computer keyboard is a device for the data input into computer and managing signals serving • It contains the standard set of the printing-press keys and some additional keys — managing and functional buttons, cursor control keys and small digital keyboard • Manipulators(mouse, joystick and other) are the special devices which are used for cursor control

18. Input devices (continued) • Joystick is ordinary bar-pen • Deviation from its vertical position leads to the movement of cursor in the proper direction within monitor screen • It is often used in computer games • Mouse is a pointing device by detecting two-dimensional motion relative to its supporting surface • The mouse's motion typically translates into the motion of a pointer within display

19. Input devices (continued) • Touchscreens are the display overlays which have the ability to display and receive information on the same screen • The effect of such overlays allows a display to be transformed in the input device removing the keyboard and/or the mouse as the primary input device • A touchpad is an input device used commonly in laptops • They are used the motions of the user’s finger • They are a substitute for a computer mouse

20. Input devices (continued) • Scanner is a device that analyzes the images and printed text and handwriting, and converts it into a digital image • Webcams are small cameras, whose images can be accessed using the World Wide Web, instant messaging, or a PC video conferencing application • Example: Skype application • A microphone is an acoustic to electric transducer or sensor that converts sound into an electrical signal • Example: Skype application

21. Output Devices • Output device is any piece of computer hardware equipment used to communicate the results of data processing carried out by an information processing system (such as a computer) to the outside world • A video adapter is a electronic board processing the video data and controlling a monitor • It sends the rays brightness management signals and sync signals of string and skilled involutes in a monitor • Monitor will transform these signals in visualisations

22. Output Devices - Monitors • Computer Display Monitoris a piece of electrical equipment which displays viewable images generated by a computer without producing a permanent record • Monitors types: • cathode-ray tube based monitors • liquid crystal displays • touch screens • There are the graphics adapters like SVGA , SXGA , UXGA , VGA , video memory , XGA

23. Output Devices (continued) • Loudspeaker, speaker, or speaker system is an electromechanical transducer that converts an electrical signal into sound • The term loudspeaker can refer to individual devices (or drivers), and complete systems consisting of an enclosure incorporating one or more drivers and additional electronics • A printer is a printing unit which carries out a conclusion from the computer of the coded information as paper-lists of text or graphic arts • There are some kind of the printers (next two slides)

24. Output Devices - Printers • Matrix printersareused by combinations of little pins that press, due to what there is a character imprint on a paper • Every character, printed on a printer, is formed from a set 9, 18 or 24 needles, formed as a vertical column • The lacks of these inexpensive printers are their noisy work and low print quality • Laser printerswork approximately similarly, as copiers • Computer forms in the memory "appearance" of text page and sends to it the printer

25. Output Devices - Printers • Ink-jet printers are generated by characters as a sequence of inks points( see next slide) • The printer plotting head has tiny nozzlesthrough which inks are put on a page • These printers demanding to paper quality • The colored ink-jet printers are created by colors • Plotteris a vector graphics printing device that connects to a computer • They can draw complex line art, including engineering drawing, architecture plans, geography and meteorology maps but do so very slowly because of mechanical movement of pens

26. Output Devices – Ink - jet printer

27. Input/Output Devices • Input/output, or I/O, refers to the communication between an information processing system (such as a computer), and the outside world – possibly a human, or another information processing system • Inputs are the signals or data received by the system, and the outputs are the signals or data sent from it • For example keyboards and mouses are considered input devices of a computer, while monitors and printers are considered output devices of a computer • Devices for communication between computers, such as modems and network cards, typically serve for both input andoutput

28. Storage Devices – Floppy Discs • Data storage device is a device for recording (storing) information (data) • Floppy diskis a data storage device that is composed of a disk of thin, flexible ("floppy") magnetic storage medium encased in a square or rectangular plastic shell • Floppy disks are read and written by a floppy disk drive or FDD, the initials of which should not be confused with "fixed disk drive", which is another term for a hard disk drive • It’s used for media conversion from one computer on other and for software distribution • The method of binary Info record on a magnetic environment is named the magnetic encoding • Magnetic domains in an environment line up along paths in the direction of the attached magnetic field by the poles of north and south

29. Storage Devices – Zip Disc • The Zip drive or Zip disc is a medium-capacity removable disk storage system, introduced by Iomega in late 1994 • Originally it had a capacity of 100 MB, but later versions increased this to first 250 MB and then 750 MB • The format became the most popular of the super-floppy type products but never reached the status of a quasi-standard to replace the 3.5-inch floppy disk • It has been superseded by flash drive systems as well as rewritable CDs and DVDs, and is practically not in use anymore

30. Storage Devices – Data Cartridges • Magnetic tape has been used for data storage for over 50 years • Modern magnetic tape is most commonly packaged in cartridges and cassettes • The device that performs actual writing or reading of data is a tape drive • Autochangers and tape libraries are frequently used to automate cartridge handling • When storing large amounts of data, tape can be substantially less expensive than disk or other data storage options. • Tape storage has always been used with large computer systems. • Modern usage is primarily as a high capacity medium for backups and archives • As of 2007, the highest capacity tape cartridges (DLT-S4, LTO-4, SAIT-2) can store 800 GB of data without using compression

31. Storage Devices – CD-ROM • CD-ROM is (an abbreviation of "Compact Disc read-only memory") is a Compact Disc that contains data accessible by a computer • While the Compact Disc format was originally designed for music storage and playback, the format was later adapted to hold any form of binary data • CD-ROMs are popularly used to distribute computer software, including games and multimedia applications, though any data can be stored (up to the capacity limit of a disc) • Some CDs hold both computer data and audio with the latter capable of being played on a CD player, whilst data (such as software or digital video) is only usable on a computer (such as PC CD-ROMs • These are called Enhanced CDs which are also known as CD Extra and CD Plus that combine audio and computer data for use in both compact disc and CD-ROM players

32. Storage Devices – CD-ROM (continued) • Capacity of CD achieves 780 Mbytes • Information is inflicted on a disk at its manufacturing and can not be changed • Changing СD-ROM technology, DVD goes swiftly • DVD has the same size like CD, but it contains up to 17 Gb i.e. one volume replace 20 standard disks of CD-ROM • Compact Disk Recordable - is capable, along with reading of ordinary compact disks, to write down information on the special optical disks • It has capacity 650 Mbytes

33. Storage Devices – Hard Disc Drive • Hard Disk Drive (HDD)commonly referred to as a hard drive, hard disk or fixed disk drive, is a non-volatile storage device which stores digitally encoded data on rapidly rotating platters with magnetic surfaces • Early HDDs had removable media; however, an HDD today is typically a sealed unit with fixed media • Non-volatile memory NVM or non-volatile storage is computer memory that can retain the stored Info even when not powered • NVM examples include read-only memory, flash memory, most types of magnetic computer storage devices (e.g. hard disks, floppy disk drives, and magnetic tape), optical disc drives, and early computer storage methods such as paper tape and punch cards

34. Storage Devices – Hard Disc Drive (continued) • Unlike a diskette, a hard disk is revolved continuously • It’s provided with a built-in cache - 8 MBytes which promotes their productivity substantially

35. Storage Devices – Hard Disc Drive (continued) • HDD has a very large capacity: from 40 to 750 Gb. At modern models speed of arbor (rotary-type billow) rotation makes 7200 rpm usually, mean data retrieval time is 9 ms, middle data rate up to 60 Mb/c • There are the external hard discs as above and the internal one • For example the Internal hard discs can be implemented as a part of the embedded systems

36. Storage Devices – Internal Hard Disc • Internal Hard Disk Drive (IHDD) is the same HDD, but it is portable and connected to computer with use of USB port - Universal Serial Bus: a standard for connection sockets on computers and other HW • Example: with the MaxConnect IHDD mounting solution, a G5 Power Mac can house a total of nine disk drives internally, which enables the system to boot from one drive and allows the rest of the disk drives to be RAIDED -Redundant Array of Inexpensive Disks • It offers 8X speed increase in the data transfer rate compared to single G5 Power Mac

37. Comparison of Storage Devices

38. Storage Devices – Disc Formatting • Disc formatting is a procedure of an initial physical or logical benchmarking for a disc • In other word it’s an operation of magnetic medium benchmarking before data are recorded there • Large disks can be partitioned, divided into logical sections that are formatted with their own file systems • Formatting a disk involves two quite different processes known as low-level and high-level formatting • Low-level formatting is the formatting of disk surfaces and installing characteristics like sector numbers that are visible to, and used by, the disk controller hardware • High-level formatting is the process of setting up an empty file system on the disk, and installing a boot sector

39. References • European Computer Driven Licence, Syllabus version 4.0, 2006. • Lecture Notes. Fundamentals of Informatics (e-version). Based on a book by L.Z.Shaucukova. Informatics (in Russian).Moscow, 2002. – 420 p. (translated and edited by Anatoly Sachenko). • William Stallings. Computer Organization and Architecture: Designing for Performance (6th edition). Prentice Hall , 2002, 750 p. • Tucker (Editor-in-Chief), R. Cupper, F.P. Deek, and R. Noonan (Editorial advisors), Computer Science Handbook, Second edition, CRC Press, 2004, 2752 p. • Hysa B., Piekoszewska B., Rakowiecka K., Sobota M., Sołtysik-Piorunkiewicz A., Zdonek D., Zdonek I., : Laboratorium z podstaw informatyki w zarządzaniu. Część II. Wprowadzenie do MS Windows. MS Word. Wydawnictwo PŚ. Gliwice 2003. Skrypt nr 2324. • Kowalczyk G.: Word 2000 PL. Ćwiczenia praktyczne. Helion, Gliwice 2000. • J. Glenn Brookshear. Computer science an overview, Sixth edition, Addison Wesley, 2001, 688 p.