1. Chapter 5 Computer Organization ( 計算機組織 )

2. Distinguish between the three components of a computer hardware. List the functionality of each component. Understand memory addressing and calculate the number of bytes for a specified purpose. After reading this chapter, the reader should be able to: O BJECTIVES Distinguish between different types of memories. Understand how each input/output device works. Continued on the next slide

3. Understand the systems used to connect different components together. Understand the addressing system for input/output devices. Understand the program execution and machine cycles. O BJECTIVES (continued) Distinguish between programmed I/O, interrupt-driven I/O and direct memory access (DMA). Understand the two major architectures used to define the instruction sets of a computer: CISC and RISC.

4. Figure 5-1 Computer hardware (subsystems)

5. CENTRALPROCESSING UNIT (CPU) CENTRALPROCESSING 5.1

6. Figure 5-2 CPU

7. MAIN MEMORY 5.2

8. Table 5.1 Memory units Unit Unit ------------ kilobyte megabyte gigabyte terabyte petabyte exabyte Exact Number of bytes Exact Number of bytes ------------------------ 2 10 bytes 2 20 bytes 2 30 bytes 2 40 bytes 2 50 bytes 2 60 bytes Approximation Approximation ------------ 10 3 bytes 10 6 bytes 10 9 bytes 10 12 bytes 10 15 bytes 10 18 bytes

9. Figure 5-3 Main memory

10. Memory addresses are defined using unsigned binary integers. Note:

11. Example 1 A computer has 32 MB (megabytes) of memory. How many bits are needed to address any single byte in memory? Solution The memory address space is 32 MB, or 2 25 (2 5 x 2 20 ). This means you need log 2 2 25 or 25 bits, to address each byte.

12. Example 2 A computer has 128 MB of memory. Each word in this computer is 8 bytes. How many bits are needed to address any single word in memory? Solution The memory address space is 128 MB, which means 2 27. However, each word is 8 (2 3 ) bytes, which means that you have 2 24 words. This means you need log 2 2 24 or 24 bits, to address each word.

13. Memory Types RAM (Random access memory): –SRAM (Static RAM) (flip-flop gates) –DRAM (Dynamic RAM) ROM (Read only memory) –PROM (programmable) –EPROM (erasable programmable) –EEPROM (electronically erasable programmable)

14. A simple flip-flop circuit Set Reset

15. Setting the output of a flip-flop to 1

16. Setting the output of a flip-flop to 1 (continued)

17. Setting the output of a flip-flop to 1

18. Another way of constructing a flip-flop

19. Figure 5-4 Memory hierarchy

20. Figure 5-5 Cache

21. INPUT / OUTPUT 5.3

22. Figure 5-6 Physical layout of a magnetic disk

23. Figure 5-7 Surface organization of a disk

24. Figure 5-8 Mechanical configuration of a tape

25. Figure 5-9 Surface organization of a tape

26. Figure 5-10 Creation and use of CD-ROM

27. Table 5.2 CD-ROM speeds Speed ------------ 1x 2x 4x 6x 8x 12x 16x 24x 32x 40x Data Rate Data Rate ------------------------ 153,600 bytes per second 307,200 bytes per second 614,400 bytes per second 921,600 bytes per second 1,228,800 bytes per second 1,843,200 bytes per second 2,457,600 bytes per second 3,688,400 bytes per second 4,915,200 bytes per second 6,144,000 bytes per second Approximation Approximation ------------ 150 KB/s 300 KB/s 600 KB/s 900 KB/s 1.2 MB/s 1.8 MB/s 2.4 MB/s 3.6 MB/s 4.8 MB/s 6 MB/s

28. Storage Device – Magnetic Device How Magnetic Storage Device Works. A magnetic disk's medium contains iron particles, which can be polarized—given a magnetic charge—in one of two directions. Each particle's direction represents a 1 (on) or 0 (off), representing each bit of data that the CPU can recognize. A disk drive uses read/write heads containing electromagnets to create magnetic charges on the medium. As the medium rotates, the head writes the data.

29. Storage Device – Magnetic Device All magnetic disks are similarly formatted, or divided into areas, called  Tracks  Sectors  Cylinders TRACKS: A track is a circular ring on one side of the disk. Each track has a number. Disk Sector: A disk sector is a wedge-shape piece of the disk, shown in yellow. Each sector is numbered. Track Sector: A track sector is the area of intersection of a track and a sector, shown in yellow. Cluster: A cluster is a set of track sectors, ranging from 2 to 32 or more, depending on the formatting scheme in use.

30. Storage Device – Magnetic Device Cylinder A cylinder comprises all the tracks (on every usable platter surface) that can be accessed by the read/write heads while the actuator assembly remains stationary.

31. Storage Device – Magnetic Device When a disk is formatted, the OS creates 4 areas on its surface. 1 Boot Sector 2 File Allocation Table 3 Root Folder 4 Data area

32. Storage Device – Optical Device How Optical Storage Works An optical disk is a high-capacity storage medium. An optical drive uses reflected light to read data. To store data, the disk's metal surface is covered with tiny dents (pits) and flat spots (lands), which cause light to be reflected differently. When an optical drive shines light into a pit, the light cannot be reflected back. This represents a bit value of 0 (off). A land reflects light back to its source, representing a bit value of 1 (on).

33. Figure 5-11 CD-ROM format

34. Figure 5-12 Making a CD-R

35. Figure 5-13 Making a CD-RW

36. Table 5.3 DVD capacities Feature Feature --------------------------------- single-sided, single-layer single-sided, dual-layer double-sided, single-layer double-sided, dual-layer Capacity Capacity ------------ 4.7 GB 8.5 GB 9.4 GB 17 GB

37. SUBSYSTEMINTERCONNECTIONSUBSYSTEMINTERCONNECTION 5.4

38. Figure 5-14 Connecting CPU and memory using three buses

39. Figure 5-15 Connecting I/O devices to the buses

40. Figure 5-16 SCSI controller (Small Computer System Interface) Daisy Chain # 7-15 devices can be connected together in a single SCSI chain. # Speed up to 160MB/sec.

41. Figure 5-17 FireWire controller (IEEE 1394) # Can support up to 63 devices # Speed 50MB/sec Upgraded to 400MB/sec

42. Figure 5-18 USB controller (Universal Serial Bus) # USB port can support up to 127 devices # USB 12Mbps USB 2.0 480Mbps (9-12) USB 3.0 5Gbps(12-286)

43. Figure 5-19 Isolated I/O addressing

44. Figure 5-20 Memory-mapped I/O addressing

45. PROGRAMEXECUTIONPROGRAMEXECUTION 5.5

46. Execution of a Program Input a value from a keyboard connected to the port at address 05H Add 7 to the value Output the result to a display connected to the port at address 02H

48. Figure 5-21 Steps of a cycle

49. Figure 5-22 Contents of memory and register before execution

50. Figure 5-23.a Contents of memory and registers after each cycle

51. Figure 5-23.b Contents of memory and registers after each cycle

52. Figure 5-23.c Contents of memory and registers after each cycle

53. Figure 5-23.d Contents of memory and registers after each cycle

54. Figure 5-24 Programmed I/O

55. Figure 5-25 Interrupt-driven I/O

56. Figure 5-26 DMA connection to the general bus

57. Figure 5-27 DMA input/output

58. TWO DIFFERENT ARCHITECTURES ARCHITECTURES 5.6

59. Two different architectures CISC (Complex Instruction Set Computer) –Intel RISC (Reduced Instruction Set Computer) –PowerPC