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Computer Organization Unit 1 Dt.21.11.17 Computer Organization unit 1 dt.21.11.17 Topics covered: Course outline and schedule Introduction General information Course : Computer Organization Instructor : dr e v Prasad Email : profevprasad @yahoo.com Lecture time : Thursday 10:00pm – 12:00 pm. Office hours : By appointment. (I will hang around for a few minutes at the end of each class). Online Resources: Supporting staff: Mrs. R Seeta Sireesha , Asst. professor Email : [email protected] Office hours : Discuss with the RSS 2 Course Objective Describe the general organization and architecture of computers. Identify computers’ major components and study their functions. Introduce hardware design issues of modern computer architectures. Learn assembly language programming. Build the required skills to read and research the current literature in computer architecture. 3 Textbooks 1. “Computer Organization,” by Carl Hamacher, Zvonko Vranesic and Safwat Zaky. Fifth Edition McGraw-Hill, 2002. 2.“SPARC Architecture, Assembly Language Programming and C,” Richard P. Paul, Prentice Hall, 2000. 4 Course topics 1. Introduction (Unit 1):Basic concepts, overall organization. 2. Machine Instruction and Programs(unit 2): fetch/execute cycle, basic addressing modes, instruction sequencing, assembly language and stacks. The role of Stacks and Queues in computer programming equation Logic Instructions shift and Rotate Instructions CISC vs. RISC architectures. 3. Logic Circuits Fundamentals(Unit 3) : Logic Gates, Combinational Circuits, Sequential circuits 4. Type of Instructions(Unit 4):Arithmetic and Logic InstructionsBranch Instructions Addressing Modes Input/output Operations 5 Cont.. 5. CPU architecture (unit 5): Single-bus CPU, Multiple-bus CPU Hardwired control, and Microprogrammed control. 6. Processing Unit (unit 6): Register Transfers, Performing An Arithmetic Or Logic Operation Fetching A Word From Memory Execution of Complete Instruction Wide Branch Addressing Microinstructions with next –Address Field 7. Arithmetic (unit 7 ): Integer arithmetic and floating-point arithmetic. 8. Memory architecture (unit 8): Memory hierarchy, Primary memory, Cache memory, virtual memory. 6 Cont.. 9. Cache Memories (unit 9): MappingFunctions,Interleaving 10. Input / Output organization (unit 10): I/O device addressing, I/O data transfers, Synchronization, DMA, Interrupts, Channels, Bus transfers, and Interfacing. 11. Bus (unit 11) : Synchronous Bus, Asynchronous Bus, Peripheral Component Interconnect (PCI) Bus, Universal Serial Bus (USB) 12. Pipelining(unit 12) : Arithmetic & Instruction Pipelining,Data Hazards,Vector Processing. 7 Grading System Midterm Exam 1 : (15) Units 1,2 and 3 during 15th -20th jan 2018 Midterm Exam 2: (15) Units 4,5 and 6 during 19th-24th mar 2018 Weightage : higher for better performed Exam: 2/3 : 1/3 Assignments : (5) -6 homework assignments. Tutorial s: Practice -3 problem solving sessions On-line Quiz 1 s: Units 1,2 and 3 during 15th -20th jan 2018 On-line Quiz 1 s: Units 4,5 and 6 during 19th-24th mar 2018 Weightage : higher for better performed Exam: 2/3 : 1/3 Final : (70) during 2nd-14th april 2018 - All topics. 8 Course topics, exams and assignment calendar Week #1 : - Introduction Week #2 : - Addressing methods - Lab. Assignment 1. Week #3 : -Addressing methods. Week #4 : - Logic Circuit Fundamentals - Lab. Assignment 2. Week #5 : - CPU Architecture. - Lab. Assignment 3. Week #6 : - CPU Architecture. - Lab. Assignment 4. Week #7 : - Arithmetic. 9 Course topics, exams and assignment calendar Week #8 : Midterm Exam Week #9 : - Arithmetic Week #10: - Memory architecture. - Lab. Assignment 5. Week #11 : - Memory organization - Lab. Assignment 6. Week #12 : - I/O organization. Week #13 - I/O devices. - Lab. Assignment 7. Week #14: - Pipelining Week #15: - Final Exam 10 Grading policy •Grading of assignments/exams is handled by the Supporting staff (RSS), if you cannot resolve a problem with RSS, see me. •Assignments may be submitted by ?hard copy and email. Hard copy will be accepted, but you have to submit in the department office to stamp the date. Please submit all the assignments to the RSS. • Late assignments are penalized by a loss of 33% per day late (so 3 days late is as late as you can get). Solution will be posted on the course web page No assignments will be accepted after the solution is posted. •The weeks during which exams will be held have been announced. The actual day of that week, (Thursday) when the exam will be held will be announced two weeks prior to the exam. If you have any conflict with the exam date, please see me in advance. 11 Important prerequisite material •Digital Logic Course is fundamental to the Computer Organization Course. •Review issues in: - Basic computer organization: CPU, Memory, I/O, Registers. - Fundamentals of combinatorial design and sequential design. - Simple ALU, simple register design -Bus structure -system software -Performance -Historical perspective 12 Reading •Reading the text is imperative. •Computer architecture especially processor design, changes rapidly. You really have to keep up with the changes in the industry. This is especially important for job interviews later. 13 Feedback Please provide informal feedback early and often, before the formal review process. 14 Basic Functional Unit of a Computer Figure 1.1. (a) Basic functional units of a computer What is a computer? a computer is a sophisticated electronic calculating machine that: Accepts input information, Processes the information according to a list of internally stored instructions and Produces the resulting output information. Functions performed by a computer are: Accepting information to be processed as input. Storing a list of instructions to process the information. Processing the information according to the list of instructions. Providing the results of the processing as output. What are the functional units of a computer? 16 Functional units of a computer Input unit accepts Arithmetic and logic unit(ALU): information: •Performs the desired •Human operators, operations on the input •Electromechanical devices (keyboard) information as determined •Other computers by instructions in the memory Memory Arithmetic Input Instr1 & Logic Instr2 Instr3 Data1 Output Data2 Control I/O Processor Stores information: Control unit coordinates Output unit sends various actions results of processing: •Instructions, •Data •Input, •To a monitor display, •Output •To a printer •Processing 17 Information in a computer -- Instructions Instructions specify commands to: Transfer information within a computer (e.g., from memory to ALU) Transfer of information between the computer and I/O devices (e.g., from keyboard to computer, or computer to printer) Perform arithmetic and logic operations (e.g., Add two numbers, Perform a logical AND). A sequence of instructions to perform a task is called a program, which is stored in the memory. Processor fetches instructions that make up a program from the memory and performs the operations stated in those instructions. What do the instructions operate upon? 18 Information in a computer -- Data Data are the “operands” upon which instructions operate. Data could be: Numbers, Encoded characters. Data, in a broad sense means any digital information. Computers use data that is encoded as a string of binary digits called bits. 19 Input unit Binary information must be presented to a computer in a specific format. This task is performed by the input unit: - Interfaces with input devices. - Accepts binary information from the input devices. - Presents this binary information in a format expected by the computer. - Transfers this information to the memory or processor. Real world Computer Memory Keyboard Audio input Input Unit …… Processor 20 Memory unit Memory unit stores instructions and data. Recall, data is represented as a series of bits. To store data, memory unit thus stores bits. Processor reads instructions and reads/writes data from/to the memory during the execution of a program. In theory, instructions and data could be fetched one bit at a time. In practice, a group of bits is fetched at a time. Group of bits stored or retrieved at a time is termed as “word” Number of bits in a word is termed as the “word length” of a computer. In order to read/write to and from memory, a processor should know where to look: “Address” is associated with each word location. 21 Memory unit (contd..) Processor reads/writes to/from memory based on the memory address: Access any word location in a short and fixed amount of time based on the address. Random Access Memory (RAM) provides fixed access time independent of the location of the word. Access time is known as “Memory Access Time”. Memory and processor have to “communicate” with each other in order to read/write information. In order to reduce “communication time”, a small amount of RAM (known as Cache) is tightly coupled with the processor. Modern computers have three to four levels of RAM units with different speeds and sizes: Fastest, smallest known as Cache Slowest, largest known as Main memory. 22 Memory unit (contd..) Primary storage of the computer consists of RAM units. Fastest, smallest unit is Cache. Slowest, largest unit is Main Memory. Primary storage is insufficient to store large amounts of data and programs. Primary storage can be added, but it is expensive. Store large amounts of data on secondary storage devices: Magnetic disks and tapes, Optical disks (CD-ROMS). Access to the data stored in secondary storage
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