1 / 59

How Computers Work

How Computers Work. Chapter 1. Hardware Needs Software to Work. Hardware – computer’s physical devices Monitor, keyboard, memory chips, hard drive Software – instructions that directs the hardware to perform a task. Hardware Needs Software to Work. Software uses hardware for 4 basic things:

butch
Télécharger la présentation

How Computers Work

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. How Computers Work Chapter 1

  2. Hardware Needs Software to Work • Hardware – computer’s physical devices • Monitor, keyboard, memory chips, hard drive • Software – instructions that directs the hardware to perform a task.

  3. Hardware Needs Software to Work • Software uses hardware for 4 basic things: • Input • Processing • Output • Storage • See figure 1-1 pg. 2

  4. Hardware Needs Software to Work • Hardware components also communicate data and instructions among themselves. • Must have electrical power system.

  5. User Interaction with Computer • Software must convert instructions given by the user into a language the computer understands. • The computer understands two things: • Yes – which means “ON” • No – which means “OFF” • Figure 1-2 pg. 3

  6. Binary Number System • 1940 – John Atanasoff can up with the idea to store and read only two values in a computer system, ON and OFF. • Either there was a charge , ON, or there wasn’t a charge, OFF. • We use the numbers 1 and 0 to represent ON and OFF – binary number system.

  7. Binary Numbering System • A 1 or 0 is called a bit. • Also called a binary digit. • Bits are generally group in groups of 8. • 8 bits make up a byte.

  8. Counting Binary Numbers • All counting and calculations use the binary number system. • Counting goes as followed: • 0, 1, 10, 11, 100, 101…….. • All letters and numbers must be converted to binary code before being stored. • Letter A – 0100 0001 • Number 25 – 0001 1001 • Figure 1-3 pg. 4

  9. PC Hardware Components Chapter 1

  10. Hardware Components • Most input/output devices are located outside the case. • Most processing and storage devices are found in the case. • The CPU is the most important device in the case.

  11. Microprocessor (CPU) • Central to all processing done by the computer. • Data received by the input devices is read by the CPU. • Output from the CPU is written to output devices.

  12. PC Hardware Components • Each input, output, and processing component requires these elements to operate: • A method for the CPU to communicate with the device. • Software to instruct and control the device. • Electricity to power the device.

  13. A method for the CPU to communicate with the device • Data must be either sent to the CPU or received from the CPU.

  14. Software to instruct and control the device • Hardware devices cannot work without software to run it. • The software must have access to the CPU in order run the device. • Each device responds to specific instructions based on the function of the device.

  15. Electricity to power the device • Electronic devices need electricity to run the device. • All computers need to have a power supply to run. • Usually an electrical outlet.

  16. Hardware Input and Output • Input/output devices are used to communicate with devices inside the computer. • Accomplished by either cables, which attach to a connection called a port, or by a wireless connection. • Most ports are found in the back of the computer. • Figure 1-4 pg. 5

  17. Input devices • Keyboard – primary input device. • Standard keyboard has 104 keys. • Mouse – a pointing device used to move a pointer on the screen and to make selections. • Can have 1, 2, or 3 buttons. • Both a mouse and keyboard can have 6 pin connector (figure 1-5) or a USB connector.

  18. Output devices • Monitor – visual device that displays the primary output of the computer. • Rated by the monitor’s resolution, which is the number of dots used to display. • Printer – produces output on paper called a hardcopy. • Most printers are either an ink-jet, laser, and solid ink.

  19. Hardware inside the computer

  20. Hardware inside the computer • Most computers can have these devices: • Motherboard containing the CPU, memory, and other components. • Hard drive, DVD and CD-ROM. • A power supply supplying electricity. • Circuit boards used by the CPU to communicate to other devices. • Cables connecting devices to circuit boards and the motherboard. • Figure 1-7 pg. 8

  21. Circuit boards • A board that holds microchips, integrated circuits (IC’s), and the circuitry that connects these chips. • Expansion Cards – circuit boards that are installed in long narrow expansion slots on the mother board. • Expansion slots – Open slots used to additional components.

  22. Circuit boards • CMOS chips (complementary metal-oxide semiconductor) • All circuit boards contain microchips which are manufactured using CMOS. • Require less electricity and produce less heat.

  23. Other components • The other main components inside the computer look like small boxes, like the power supply, floppy drive, hard drive, and CD-ROM.

  24. Cables • Two types of cables are found inside the computer: • Data cables – connect devices to one another. • Flat and wide cables • Power cables – supply power. • Round and small cables

  25. The motherboard

  26. The motherboard • The largest and most important circuit board. • Also called the system board and main board. • Contains the CPU. • Because of the complexity and importance of the CPU, all devices are either installed on the mother board or connect to it.

  27. The motherboard • Devices that are not on the motherboard is called a peripheral device. • Some ports stick outside the case to connect to external devices. • Figure 1-8 pg. 9

  28. The mother board • Serial ports – named because data is transferred serially (one bit follows the next). • Parallel ports – transmits data in parallel and is most commonly used by a printer. • Universal Serial Bus ports (USB) – used by a number of input/output devices. • 1394 port – used by high speed multimedia devices such as digital camcorders. • Figure 1-9 pg. 10

  29. Items found on the motherboard • Processing components • CPU – most important chip. • Chip set – controls motherboard activities • Temporary storage • Random Access Memory (RAM) – holds data and instructions as they are processed. • Cache memory – speed ups memory access.

  30. Items found on the motherboard • Components that communicate with the CPU with other devices. • Traces – wires on the motherboard used for communication. • Expansion slots – connect expansion cards to the motherboard. • System clock – keeps communication in sync. • Electrical system • Provide power to the motherboard and expansion cards.

  31. Items found on the motherboard • Programming and setup data • Flash ROM – a memory chip used to permanently store instructions that control hardware functions. • CMOS chip – holds configuration data.

  32. The CPU and the Chip Set • The CPU could not do it’s job without the assistance of the chipset. • Chipset – group of microchips on the motherboard that control the flow of data and instructions to and from the CPU. • Figure 1-10 pg. 11 • Figure 1-11 pg. 12

  33. Storage Devices • 2 types of storage: • Temporary and Permanent • CPU uses temporary storage called primary storage or memory. • Primary storage is much faster to access than permanent memory.

  34. Storage Devices • When data and instructions are not being used, they are stored in permanent storage called secondary storage. • Floppy disk, hard drive • Figure 1-12 pg. 13

  35. Primary Storage • Primary storage is provided by devices called RAM • Random Access Memory • Located on the motherboard and other circuit boards • RAM chips are installed directly on a small board on the motherboard or in banks that plug into the motherboard. • Figure 1-13 pg. 14

  36. Primary Storage • The most common types of boards that hold memory are: • Single Inline Memory Modules (SIMM) • Dual Inline Memory Modules (DIMM) • Rambus Inline Memory Modules (RIMM) • Memory in RAM is lost when the computer is shut off. • They need a continuous supply of electricity.

  37. Primary Storage • Because RAM always needs electricity, it is referred to as volatile memory. • However, there is nonvolatile memory called ROM (Read Only Memory). • Holds data even when no electricity is present. • Figure 1-14 pg. 14

  38. Secondary Storage • Data that is stored on devices such as CD’s, disks, hard drives, and so on. • Data and instructions can not be processed from these locations. • It must first be copied to Primary Storage. • IMPORTANT: secondary memory is PERMANENT memory.

  39. Secondary Storage • Hard drive – a sealed case containing platters and disks that rotate at a high speed. • Figure 1-16 pg. 16 • As platters rotate, an arm reaches across the platters, both writing new data and reading existing data.

  40. Hard drives • Hard drives use a technology called: • Integrated Drive Electronics (IDE) • IDE provides two connectors on a motherboard for two data cables. • Figure 1-17 pg. 17 • Figure 1-18 pg. 17 • A motherboard can accommodate up to 4 IDE’s • Hard drives, ZIP drives, CD-ROMs all use these IDE connections.

  41. Hard drive • Receives its power from the power supply by way of a power cord. • Figure 1-19 pg. 18

  42. Other Secondary Storage Devices • Floppy Drive • Holds up to 1.44 MB of data • CD-ROM Drive • Most software is distributed by CD-ROM

  43. Motherboard Components use for Communication Among Devices • Traces – circuits (paths) that enable data, instructions and power to transfer from component to component. • This system of pathways used for communication and the protocol and methods used for transmission are called the bus.

  44. Motherboard Components use for Communication Among Devices • Protocol – set of rules and standards that any two entities use for communication. • Data bus – paths, or lines of the bus that are used to move data. • Figure 1-24 pg. 21

  45. Motherboard Components use for Communication Among Devices • Binary data is put on a line of a bus by placing voltage on that line. • This voltage is traveling on top of the line, not on it.

  46. Transferring data between components • When one component at one end of the line wants to write data to another component, the two must get in sync for the write operation. • The first component places voltage on several lines of the bus, and the other component immediately reads the voltage on those lines.

  47. Transferring data between components • The CPU interprets the voltage on each line as binary digits. • Some buses have data paths that are 8, 16, 32, 64, or 128 bits wide. • If a bus has 8 wires to transmit data, it is called an 8 bit bus. • Remember: There are only two states inside a computer. On or Off. • If there is a voltage, then it is represented by a 1, and just the opposite if there is no voltage. • Figure 1-25 pg. 22

  48. Bus • Data Path Size – width of a data bus. • There can be multiples buses on a motherboard. • The main bus on the motherboard has several different names: • System bus • Memory bus • Host bus • Local bus • Front Side bus (FSB)

  49. System clock • System clock – circuit dedicated to timing the activities of the chips on the motherboard. • Figure 1-26 pg. 23 • Clock speed – the number of beats which are measured in Hertz (Hz) • Hertz – one cycle per second. • Megahertz (MHz) – one million cycles per second. • Gigahertz (GHz) – one billion cycles per second.

  50. Transferring data between components • The lines of a bus often expand to expansion slots. • Figure 1-27 pg. 24 • The kind of bus you depends on the type of expansion slot.

More Related