Introduction to Computer Applications and Concepts ITE 115

2. Introduction to Computer Applications and Concepts ITE 115 Chapter 4 Digital Electronics and File Management

3. Objectives • Discuss digital data representation • Introduce integrated circuits • Explore processors • Introduce computer memory: RAM • Explore computer memory

4. Objectives • Introduce computer file basics • Examine file locations • Introduce file management • Explore file management • Examine file storage

5. Discuss Digital Data Representation • The form in which information is conceived, manipulated and recorded on a digital device • Uses discrete digits/electronic signals • Binary number system • On/Off; Yes/No; 1/0 • Byte = 8 bits = 1 character

6. Discuss Digital Data Representation • Numeric data: • Represents quantities used in arithmetic operations. • Character data: • Letters, symbols, and numbers not used in arithmetic operations. • Computers must digitize pictures and sounds

7. Discuss Digital Data Representation • Most files have file headers • Codes that represent character data: • ASCII, EBCDIC, Unicode • Extended ASCII (shown below)

8. Quantifying Bytes and Bits • Bit = b • Nibble = Half of a byte • Byte = B • Kilobyte (KB) (1024 bytes) • Megabyte (MB) (Million bytes) • Gigabyte (GB) (Billion bytes) • Terabyte (TB) (Trillion bytes)

9. Introduce Integrated Circuits A super thin slice of semi–conducting material packed with microscopic circuit elements such as wires, transistors, capacitors, logic gates, and resistors. Bits are represented as electrical pulses that travel over these circuits. Also called a chip, microchip and computer chip.

10. Integrated Circuits (cont.) • Chips are classified by number of components they contain • SSI (small-scale integration), less than 100 components per chip • ULSI (Ultra large-scale) over 1 million • Semi conducting materials used to make chips • Silicon and germanium

11. Chip Package Integrated Circuit Uses • Processors • Memory • Support circuitry

12. Processor Packages • DIPs (dual in-line packages) • DIMMs (dual in-line memory modules) • PGAs (Pin-grid arrays) • SECs (single-edge contact cartridges)

13. Microprocessor (Processor) • Designed to process instructions • Largest chip on motherboard • Intel: world’s largest chipmaker (Pentiums) • AMD: Cheaper chips (Athlons)

14. Motherboard • Main circuit board

15. Processor Components ALU (Arithmetic Logic Unit) Control Unit

16. Processor Performance • Speed: processor clock set clock speed (MHz or GHz ) • Word Size: number of bits the processor can manipulate at one time (32-bit or 64-bit) • Cache: high speed memory (kilobytes)

17. Processor Performance • Instruction Set Type: • CISC (Complete instruction set computer) • RISC (Reduced instruction set computer) • Processing Technique: • Serial • Pipelining • Parallel • Dual-core • Look at benchmark testing to compare

18. Memory Types • Random Access Memory (RAM) • Virtual Memory • Read-Only Memory (ROM) • CMOS

19. RAM (Random Access Memory) • Temporary (volatile) holding area for data, application software and operating system • Expensive chip set • Circuitry • Less storage than disk • Capacitors hold bits • Capacity measured in MB • Speed in nanoseconds • Makes the most noticeable difference

20. RAM Types • SDRAM • Synchronous Dynamic RAM • fast and cheap • DIMMS • Most popular • RDRAM • Rambus Dynamic RAM • faster and more expensive • RIMMs and SO-RIMMs

21. Virtual Memory • Disk-based • Stores parts of programs and data until they are needed by the processor • Works with RAM, but is slower

22. ROM (Read-Only Memory) • Permanent on a chip from manufacturer • Holds computer start up routine, which are hard-wired instructions • Only way to change is to replace ROM chip • ROM BIOS (basic input/output system)

23. CMOS (Complementary Metal Oxide Semiconductor) • Battery powered • More permanent than RAM; less permanent than ROM • Stores basic computer configuration • Must be updated via CMOS setup program when configuration changes

24. capacity speed type ComputerAds • Includes: capacity, speed, and type of RAM • Also maximum RAM that can be installed • Example: 512 MB 400 MHZ SDRAM

25. Computer File Characteristics • A collection of data on a storage medium • Filename conventions • Filename extension indicates native file format .txt .jpg .exe .doc

26. C:\Music\Reggae\Marley One Love.mp3 Drive letter Primary folder Secondary folder Filename Filename extension File Locations • Device drive letters A: C: D: • Directory • Root Directory (C:\) • Subdirectory or folder (C:\Documents) • File specification or path • File size and date

27. Deleting Files • Move to Recycle Bin in Windows • Undelete • Empty Bin

28. File Management • Helps you organize your computer files • File/Save and File/Open • Save vs. Save As • Desktop search tools

29. File Management Tools • Utilities like Windows Explorer or Macintosh: Finder or Spotlight • list, find, move, copy, delete, rename • Filing cabinet or tree model • Metaphors to help you visualize files on a storage device • Folder hierarchy

30. Using Files • Start application (open Word) • Create file (type text) • Save file (File/Save) • Close file and application (File/Exit) • Open file again for editing (File/Open) • Edit file • Save file (with changes, or rename) • File/Save • File/Save As

31. Organizing Files • On your computer: • Give files and folders descriptive names • Keep file extensions so files open with correct software • Group similar files into folders • Organize folders from top-down to make retrieval and backup easier

32. Examine File Storage • Logical storage • Windows Explorer creates a mental image of how to create, save, and retrieve files • Physical storage • How the data is stored on your computer • File system keeps track of names and file locations. • Windows uses FAT32 or NTFS • Backup your index file

33. Examine File Storage • Clusters: a group of sectors that speeds up storage and retrieval • FAT (File Allocation Table) on each disk keeps track of where all files are and which clusters are empty; if damaged, you lose everything • Defragmentation Utility rearranges files to be stored in contiguous clusters

34. Tech Talk: How a processor executes instructions • Complex task broken down into a series of simple steps or instructions • Instructions are in machine code (0s and 1s) and consist of: • Op code: Operation code like Add, Compare, etc • Operand: data address for operation

35. Tech talk: How a processor executes instructions • Instruction Set is built into processor • Instructional Cycle is the execution of a single instruction Interpret Instruction Fetch Instruction Execute Instruction Increment Instruction Pointer

36. Context: Banking • Automated check clearing • Check fraud • ATMs • Internet banking • Online bill-paying • Security concerns

37. Issue: Online Voting • Basic requirements for democratic voting systems • Allow voters to cast votes remotely • Technical and security issues

38. Unit Summary • Computers digitize information • Processors interpret instructions • RAM, Virtual, ROM, and CMOS are memory types • Computers store files logically (Windows Explorer) and physically (in clusters on disks)

39. Digital Electronics and File Management End