Computer Organization & Assembly Language Programming CSE 2312 Lecture 2 Introduction to Computers 1
Languages, Levels, Virtual Machines A multilevel machine 2
Contemporary Multilevel Machines A six-level computer. The support method for each level is indicated below it. 3
How to bridge gap? Idea Designing the L1 language including a new set of instructions that is more convenient for people to use than those in built-in machine instructions (L0 language) Solution: Translation Executing a program written in L1 is first to replace each L1 s instruction with an equivalent sequence of L0 s instructions The computer executes the new L0 program instead of the original L1 program Solution: Interpretation Write a program in L0 to take programs in L1 as input data Examine each instruction in turn and execute the equivalent sequence of L0 instructions directly 4
Translation and Interpretation Similarity In both of them, the computer carried out instructions in L1 by executing equivalent sequences of instructions in L0 Difference In translation, the entire L1 program is converted to an L0 program. Then the new L0 program is loaded into the memory and executed. During execution, the new L0 program runs and is in control of computer In interpretation, after each L1 instruction is examined and decoded, it is carried out immediately. The interpreter is in control of computer. In this case, L1 program is just input data. 5
Hardware or Software? 6
Evolution of Multilevel Machines Invention of microprogramming 1 st digit computer in 1940 only had ISA level and digital logic level It made the digital logic level circuit very complicated, unreliable, difficult to understand and build Microprogramming is designed (Wilkes,1951) as unchangeable interpreter to execute the ISA-level programs by interpretation This enables fewer electronic circuits and hence enhance the reliability Invention of operating system Earlier computers were open-shop, which meant the programmers had to operate the computer by themselves First designed in 1960 to reduce the amount of operating time/complexity by automating the operator s job 7
Operating System Tasks Steps Put the big green deck labeled FORTRAN complier into the card reader, start Put his/her Fortran program into the card reader. Read it two times. The translation is completed and check if there exist errors. If no, the machine language is punched out into the cards Put the translated machine language cards and subroutine library deck in The program began executing. Programmers check problems while CPU is idle. sample job for the FMS operating system (IBM 709). 8
Evolution of Multilevel Machines Migration of functionality to microcode Add new instructions (hardware) by extending microprogram The added ones are not essentially but slightly faster than a sequence of existing instructions Speeding up the particular activity Elimination of microprogramming Computer design had come full circle The microprogramming is too fat. The computer became slower and slower Eliminating the microprogram vastly reduces the instruction set Having the remaining instructions be directly executed by hardware 9
Milestones in Computer Architecture Some milestones in the development of the modern digital computer 10
Milestones in Computer Architecture (cont d) Some milestones in the development of the digital computer 11
Computer Generations Zeroth Generation Mechanical Computers (1642 1945) First Generation Vacuum Tubes (1945 1955) Second Generation Transistors (1955 1965) Third Generation Integrated Circuits (1965 1980) Fourth Generation Very Large Scale Integration (1980?) 12
Recalling: Original Von Neumann Architecture Model of a computer that used stores programs Both data and program stored in memory Allows the computer to be re-programmed 13
PDP-8 Innovation Single Bus The PDP-8 omnibus 14
IBM 360 The initial offering of the IBM product line. 15
Moore s Law Moore s Law Gordon Moore was an Inter Engineer An observation about improvements in hardware Predicts a 60-percent annual increase in the number of transistors that can be put on a chip. Processor Speed Number of transistors on a chip double every 18 months Processors speed 2x every 18 months Memory Capacity 2x every 2 years Disk Capacity 2x every year 16
Applied to Transistors on a Chip Moore s law Predicts a 60-percent annual increase in the number of transistors that can be put on a chip. The data points given in this figure are memory sizes, in bits. 17
Clock Speed 18
Processor Performance 19
Memory Price 20
Hard Disk Drive Capacity 21
CPU Cycles Unbalanced system improvements Latencies of Cache, DRAM and Disk in CPU Cycles 5,000,000 5000000 4500000 4000000 3500000 3000000 2500000 2000000 1500000 1000000 500000 0 0.3 0.375 87,000 1.2451,807 560,000 2 0.9 0.7 2.5 11.66 1,666,666 1.25 1980 1985 1990 1995 2000 Year SRAM Access Time DRAM Access Time Disk Seek Time The Bryant disks and O Hallaron, in 2000 Computer are more Systems: than A 57 Programmer s times SLOWER Perspective, than their ancestors Prentice in 1980. Hall, 2003. 37.5 22
Different Computers Greeting Card (electronic music) $1 Electronic control in cars $5~$10 Game Computer $50~$100 Personal Computer $500~$1,000 Computer Servers $5,000 Mainframe Computer $5,000,000 23
Different Computers 24
Microcontrollers Appliances Communications gear Computer peripherals Entertainment devices Imaging devices Medical devices Military weapon systems Shopping devices Toys
Radio-frequency identification (RFID) RFID contains a tiny radio transponder and a built-in unique 128-bit number They are powered by the incoming radio signal to transmit their number back to the antenna. Small RFID chips, here compared to a grain of rice
Personal Computer Printed circuit board The heart of every personal computer. (Figure: Intel D875PBZ board) 7 5 10 6 4 2 3 1 8 9 1. Pentium 4 socket 2. 875P Support chip 3. Memory sockets 4. AGP connector 5. Disk interface 6. Gigabit Ethernet 7. Five PCI slots 8. USB 2.0 ports 9. Cooling technology 10. BIOS 27
Representatives in Major Computer Families Pentium 4 by Intel Popular personal computer UltraSPARC III by Sun Microsystems Open architecture with many suppliers of parts and systems Aimed at high-end applications, such as large multiprocessor web servers with dozens of CPUs and physical memories. The 8051 chip by Intel, used for embedded systems Use read-only memories for the program plus a small amount of read-write memory, called RAM (Random Access Memory) for data storage Cheaper price 28
Intel CPU Computer Family 29
The Intel Pentium 4 Chip 30
The Intel Core i7 Chip The die is 21 by 21 mm and has 2.27 billion transistors.
Moore s law for Intel CPU Chips. 32
Development Trends Advanced Architectures Multi-core (more than 1 CPU on a chip) Performance Accelerators Graphic chips (Xbox, Wii, nintendo) Probability Processing Embedded Computing Processors in vending machines, washer dryers, cars Cloud Computing Computing as a utility Low Energy Design Green is in Dual Core CPU 33
Nvidia Tegra 2 system on a chip
Exercise Ex 1: TRUE OR FALSE, Why? An interpreter converts programs in one language to another, while a translator carries out a program instruction by instruction. Answer: F Reason: An translator converts programs in one language to another, while a interpreter carries out a program instruction by instruction. Ex 2: TRUE OR FALSE, Why? L4 language (assembly language) is less convenient for people to use than those in built-in machine instructions (L2). Answer: F Reason: L4 language is more convenient for people 35
Exercise Ex 3: TRUE OR FALSE, Why? Hardware and software are functionally equivalent. Any function done by one can, in principle, be done by the other. Answer: T Ex 4: Which of following statements are true for translation and Interpretation? (a) In translation, the entire L1 program is converted to an L0 program. (b) In interpretation, after each L1 instruction is examined and decoded, it is carried out immediately. (c) Interpretation is more efficient than translation Answer: [a, b] 36
Exercise Ex 5: Which of following can be stored in the memory? (a) Data only (b) Program only (c) Both data and program (d) None of them Answer: [c] 37
Exercise Ex 6: Which of following is true according to Moore s Law: (a) 2X processor speed improvement every 8 months. (b) 2X processor speed improvement every 18 months. (c) 4X processor speed improvement every 8 months. (d) 4X processor speed improvement every 18 months. Answer: [b] 38
Exercise Ex 7: Which of following is true in multilevel machine? (a) Instruction Set Architecture Level lays between Digital Logic Level and Microarchitecture Level. (b) Assembly Language Level lays between Instruction Set Architecture Level and Operating System Level (c) Operating System Level lays between Assembly Language Level and Instruction Set Architecture Level (d) Microarchitecture Level lays between Digital Logic Level and Instruction Set Architecture Level Answer: [c, d] 39
Exercise Ex 8: What is the key gap in computer design? How to bridge this gap? Answer: Human prefers natural language while it s easy to use machine (binary) language for computers. Designing a high level language (L1) including a new set of instructions that is more convenient for people to use than those in built-in machine instructions (L0 language). 40