CDA 3100 Spring 2009 Special Thanks Thanks to

CDA 3100 Spring 2009

Special Thanks • Thanks to Dr. Xiuwen Liu for letting me use his class slides and other materials as a base for this course

Class organization • Class web page – http: //www. cs. fsu. edu/~zzhang/CDA 3100_Spring _2009. htm – Academic honor code – Programs you submitted must be your own work – While discussions of class materials and assignments are allowed, copying of solutions is strictly prohibited 9/25/2020 CDA 3100 3

Class Communication • This class will use class web site to post news, changes, and updates. So please check the class website regularly • Please also make sure that you check your emails on the account on your University record 9/25/2020 CDA 3100 4

Required Textbook • The required textbook for this class is – “Computer Organization and Design” • The hardware/software interface – By David A. Patterson and John L. Hennessy – Third Edition – Morgan Kaufmann Publishers, part of Elsevier – 2007 – We will cover chapters 1 -4, part of 5, and appendix A, B 9/25/2020 CDA 3100 5

Lecture Notes and Textbook • All the materials that you will be tested on will be covered in the lectures – Even though you may need to read the textbook for review and further detail explanations – The lectures will be based on the textbook and handouts distributed in class 9/25/2020 CDA 3100 6

Programming Environment at CS • For this class, we will use “linprog” most of the time – “linprog” is a machine stack, consisting of four Pentium III machines • Running Linux 2. 6. 9 • Another available machine stack is “program”, consisting of four Sun workstations (Sun-Fire. V 240, sparc ISA) – Running Sun. OS 5. 10 • Using ssh to remotely login to these machines 9/25/2020 CDA 3100 7

What you will learn to answer (among other things) • How does the software instruct the hardware to perform the needed functions • What is going on in the processor • How a simple processor is designed

Computer System Overview • A computer system consists of hardware and software that are combined to provide a tool to solve problems (with best performance) – Hardware includes CPU, memory, disks, printers, screen, keyboard, mouse. . . – Software includes • System software – A general environment to create specific applications • Application software – A tool to solve a specific problem 9/25/2020 CDA 3100 9

Computer System Overview – cont. 9/25/2020 CDA 3100 10

Steps to Run a C Program • First we need to compile the program 9/25/2020 CDA 3100 11

Steps to Run a C Program • Then we need to run the program – The operating system locates where the program is – Then it loads the program into memory – The instructions in the program are then executed one by one – When the program is done, the operating system then releases the memory and other resources allocated to the program 9/25/2020 CDA 3100 13

Opening the Box 9/25/2020 CDA 3100 14

A Pentium 4 Processor Chip 9/25/2020 CDA 3100 15

Five Classic Components 9/25/2020 CDA 3100 16

Hierarchical Abstraction • We focus on principles underlying these computer systems using hierarchical abstractions 9/25/2020 CDA 3100 17

Hierarchical Abstractions – – Applications/systems software Assembly/machine language Architectural issues: i. e. , caches, virtual memory, pipelining Boolean logic, 1 s and 0 s • Sequential logic, finite state machines • Combinational logic, arithmetic circuits – Transistors used to build logic gates (CMOS) – Semiconductors/silicon used to build transistors – Properties of atoms, electrons, and quantum dynamics • In this class we focus on the software-hardware interface – Known as the instruction set architectures (ISA) 9/25/2020 CDA 3100 18

Instruction Set Architecture • A very important abstraction – Interface between hardware and low-level software – Standardizes instructions, machine language bit patterns, etc. – Advantage: different implementations of the same architecture • Modern instruction set architectures – IA-32, Power. PC, MIPS, SPARC, ARM, …

Market 9/25/2020 CDA 3100 20

Why This Class Important? • If you want to create better computers – It introduces necessary concepts, components, and principles for a computer scientist – By understanding the existing systems, you may create better ones • If you want to build software with better performance • If you want to have a good choice of jobs • If you want to be a real computer science major 9/25/2020 CDA 3100 21

Career Potential for a Computer Science Graduate http: //www. jobweb. com/studentarticles. asp x? id=904&terms=starting+salary 9/25/2020 CDA 3100 22

Career Potential for a Computer Science Graduate Source: NACE Fall 2005 Report (http: //www. jobweb. com/resources/library/Careers_In/Starting_Salary_51_01. htm) 9/25/2020 CDA 3100 23

Numbers • Numbers are abstraction of quantities – http: //www. debtclock. com/ – How do we represent these quantities? 9/25/2020 CDA 3100 24

Decimal Numbering System • We humans naturally use a particular numbering system 9/25/2020 CDA 3100 25

Decimal Numbering System • For any nonnegative integer value is given by , its – Here d 0 is the least significant digit and dn is the most significant digit 9/25/2020 CDA 3100 26

Decimal Numbering System • For any nonnegative integer is given by , its value val = 0; While there are more digits, end 9/25/2020 CDA 3100 27

General Numbering System – Base X • Besides 10, we can use other bases as well – In base X, the value of 9/25/2020 CDA 3100 28

General Numbering System – Base X • Besides 10, we can use other bases as well – In base X, the value of val = 0; While there are more digits, end 9/25/2020 CDA 3100 29

Commonly Used Bases Base Common Name Representation Digits 10 Decimal 5023 ten or 5023 0 -9 2 Binary 10011111 two 0 -1 8 Octal 11637 eight 0 -7 16 Hexadecimal 139 Fhex or 0 x 139 F 0 -9, A-F – Note that other bases are used as well including 12 and 60 • Which one is natural to computers? – Why? 9/25/2020 CDA 3100 30

Meaning of a Number Representation • When we specify a number, we need also to specify the base – For example, 10 presents a different quantity in a different base There are 10 kinds of mathematicians. Those who can think binarily and those who can't. . . http: //www. math. ualberta. ca/~runde/jokes. html 9/25/2020 CDA 3100 31

Conversion between Representations • Now we can represent a quantity in different number representations – How can we convert from one representation to another one? – For example, how can we convert a decimal number to binary? – How can we then convert a binary number to a decimal one? – How can we convert between base X 1 and base X 2? 9/25/2020 CDA 3100 33

Conversion Between Bases • From binary to decimal example 15 10 9 8 7 6 5 4 3 2 1 0 215 214 213 212 211 210 29 28 27 26 25 24 23 22 21 20 1 1 1 0 9/25/2020 14 0 13 0 12 1 11 0 0 CDA 3100 34

Conversion Between Bases • From octal to decimal • From hexadecimal to decimal 9/25/2020 CDA 3100 35

Conversion Between Bases • From base X to decimal (base 10) 9/25/2020 CDA 3100 36

Conversion Program 9/25/2020 CDA 3100 37

Conversion from Decimal to Base X • Given 5023 ten, what is the representation in the following bases? – Binary? – Hexadecimal? – Octal? 9/25/2020 CDA 3100 38

Conversion from Decimal to Base X • We have the following formula – How do we generate d 0? 9/25/2020 CDA 3100 39

Conversion from Decimal to Base X • We have the following formula – How do we generate d 0? • Divide by X, the reminder is d 0 – How do we generate d 1? • Divide the quotient by X again and the reminder is d 1 9/25/2020 CDA 3100 40

Conversion between Two Bases • We can always do the conversion in two steps, from base 1 to decimal and from decimal to base 2 • In some cases, the conversion is straightforward – For example, we often need to convert between a binary number and a hexadecimal number 9/25/2020 CDA 3100 42

Number Representations in Computers • Binary is the natural choice for computers – Since computers consist of transistors which have two different states • Additionally, for efficiency, we typically use a fixed number of bits – unsigned char – unsigned short – unsigned int • unsigned long – The least significant bit is the rightmost bit while the most significant bit is the leftmost bit – Overflow occurs if a number can not be represented correctly in the given format 9/25/2020 CDA 3100 43

Unsigned Formats and Their Ranges Type (C) Number of bits Largest number (decimal) unsigned char 8 255 unsigned short 16 65535 unsigned int 32 4, 294, 967, 295 unsigned long 64 18, 446, 744, 073, 709, 551, 615 Exact arithmetic ? ? 9/25/2020 CDA 3100 44