1. Your Interactive Guide to the Digital World Discovering Computers 2012 Lecture -1

2.  The system unit is a case that contains electronic components of the computer used to process data Discovering Computers 2012: Chapter 4 2 Page 210 Figure 4-1

3.  The inside of the system unit on a desktop personal computer includes: Discovering Computers 2012: Chapter 4 3 Page 211 Figure 4-2 Drive bay(s)Power supplySound cardVideo cardProcessorMemory

4.  The motherboard is the main circuit board of the system unit ◦ A computer chip contains integrated circuits Discovering Computers 2012: Chapter 4 4 Page 212 Figure 4-3

5.  The processor, also called the central processing unit (CPU), interprets and carries out the basic instructions that operate a computer ◦ Contain a control unit and an arithmetic logic unit (ALU) Discovering Computers 2012: Chapter 4 5 Page 213 Multi-core processor Dual-core processor Quad-core processor ????-core processor

6. Discovering Computers 2012: Chapter 4 6 Page 213 Figure 4-4

7.  The control unit is the component of the processor that directs and coordinates most of the operations in the computer  The Arithmetic Logic Unit (ALU) performs arithmetic, comparison, and other operations ◦ Arithmetic operations like +, x, -, / ◦ Logic operations like =, Discovering Computers 2012: Chapter 4 7 Page 214

8.  For every instruction, a processor repeats a set of four basic operations, which comprise a machine cycle Discovering Computers 2012: Chapter 4 8 Page 215 Figure 4-5

9. The processor contains registers, that temporarily hold data and instructions The system clock controls the timing of all computer operations The pace of the system clock is called the clock speed, and is measured in gigahertz (GHz). This is used to measure the speed of a computer. What is the speed of your computer? Discovering Computers 2012: Chapter 4 9 Page 216

10.  The leading manufacturers of personal computer processor chips are Intel, AMD and Nvidia (soon). Discovering Computers 2012: Chapter 4 10 Pages 216 – 217 Figure 4-7

11.  A processor chip generates heat that could cause the chip to burn up  Require additional cooling ◦ Heat sinks ◦ Liquid cooling technology Discovering Computers 2012: Chapter 4 11 Pages 219 - 220 Figures 4-9 – 4-10

12.  Parallel processing uses multiple processors simultaneously to execute a single program or task ◦ Massively parallel processing involves hundreds or thousands of processors Discovering Computers 2012: Chapter 4 12 Page 220 Figure 4-11

13. Analog signals are continuous and vary in strength and quality Digital signals are in one of two states: on or off Most computers are digital The binary system uses two unique digits (0 and 1) Bits and bytes Discovering Computers 2012: Chapter 4 13 Page 221

14. A computer circuit represents the 0 or the 1 electronically by the presence or absence of an electrical charge Eight bits grouped together as a unit are called a byte. A byte represents a single character in the computer Discovering Computers 2012: Chapter 4 14 Page 221 Figures 4-12 – 4-13

15.  ASCII (American Standard Code for Information Interchange) is the most widely used coding scheme to represent data Discovering Computers 2012: Chapter 4 15 Page 221 Figure 4-14

16. Discovering Computers 2012: Chapter 4 16 Page 222 Figure 4-15

17.  Memory consists of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of processing the data  Stores three basic categories of items: Discovering Computers 2012: Chapter 4 17 Page 223 The operating system and other system software Application programs Data being processed and the resulting information

18.  Each location in memory has an address  Memory size is measured in kilobytes (KB or K), megabytes (MB), gigabytes (GB), or terabytes (TB) Discovering Computers 2012: Chapter 4 18 Page 223 Figure 4-17

19.  The system unit contains two types of memory: Discovering Computers 2012: Chapter 4 19 Pages 223 - 224 Volatile memory Loses its contents when power is turned off Example includes RAM Nonvolatile memory Does not lose contents when power is removed Examples include ROM and flash memory

20.  RAM chips usually reside on a memory module and are inserted into memory slots Discovering Computers 2012: Chapter 4 20 Page 225 Figure 4-20

21.  Memory cache speeds the processes of the computer because it stores frequently used instructions and data Discovering Computers 2012: Chapter 4 21 Page 227 Figure 4-22

22. Read-only memory (ROM) refers to memory chips storing permanent data and instructions Firmware A PROM (programmable read-only memory) chip is a blank ROM chip that can be written to permanently EEPROM can be erased Discovering Computers 2012: Chapter 4 22 Page 228

23.  Flash memory can be erased electronically and rewritten ◦ CMOS technology provides high speeds and consumes little power used to hold time, date and basic system parameters. Discovering Computers 2012: Chapter 4 23 Pages 228 – 229 Figure 4-23

24.  Access time is the amount of time it takes the processor to read from memory ◦ Measured in nanoseconds Discovering Computers 2012: Chapter 4 24 Page 229 Figures 4-24 – 4-25

25.  An expansion slot is a socket on the motherboard that can hold an adapter card  An adapter card enhances functions of a component of the system unit and/or provides connections to peripherals ◦ Sound card and video card Discovering Computers 2012: Chapter 4 25 Page 230 Figure 4-26

26.  With Plug and Play, the computer automatically can configure adapter cards and other peripherals as you install them Discovering Computers 2012: Chapter 4 26 Pages 230 – 231 Figure 4-27

27.  Removable flash memory includes: ◦ Memory cards and USB flash drives Discovering Computers 2012: Chapter 4 27 Page 231 Figure 4-28

28. A port is the point at which a peripheral attaches to or communicates with a system unit (sometimes referred to as a jack) A connector joins a cable to a port Discovering Computers 2012: Chapter 4 28 Page 232

29. Discovering Computers 2012: Chapter 4 29 Page 232 Figure 4-29

30.  On a notebook computer, the ports are on the back, front, and/or sides Discovering Computers 2012: Chapter 4 30 Pages 232 - 233 Figure 4-30

31. Discovering Computers 2012: Chapter 4 31 Page 233 Figure 4-31

32.  A USB port can connect up to 127 different peripherals together with a single connector ◦ You can attach multiple peripherals using a single USB port with a USB hub Discovering Computers 2012: Chapter 4 32 Page 234 Figure 4-32

33. A Bluetooth wireless port adapter converts a USB port into a Bluetooth port. But nowadays most notebooks and smart phones have built-in Bluetooth device. Page 235 Figures 4-33 – 4-34 Discovering Computers 2012: Chapter 4 33

34.  A bus allows the various devices both inside and attached to the system unit to communicate with each other. Discovering Computers 2012: Chapter 4 34 Page 237 Figure 4-36

35.  A bay is an opening inside the system unit in which you can install additional equipment ◦ A drive bay typically holds disk drives Discovering Computers 2012: Chapter 4 35 Page 238 Figure 4-37

36. The power supply converts the wall outlet AC power into DC power Some external peripherals have an AC adapter, which is an external power supply Discovering Computers 2012: Chapter 4 36 Page 239

37. Personal computer you can carry from place to place Examples include notebook computers, laptop computers, netbooks, ultra-thins, and Tablet PCs Mobile Computer Computing device small enough to hold in your hand Examples include smart phones and PDAs, e- book readers, handheld computers, portable media players, and digital cameras Mobile Device 37 Pages 20 - 23 Discovering Computers 2012: Chapter 1

38. Notebook computer Tablet PC Smart phones and PDAs E-book reader 38 Pages 20 - 22 Figures 1-17 – 1-20 Discovering Computers 2012: Chapter 1

39. Handheld computer Portable media player Digital camera 39 Pages 22 - 23 Figures 1-21 – 1-23 Discovering Computers 2012: Chapter 1