2. 1 ECSE-2610 Computer Components & Operations (COCO) Welcome to the world of Computers!

3. 2 The Digital World

4. 3 Information Processing Systems, especially computers, are driving the world economy. –The Internet is changing the way we communicate, shop, learn, invest, and entertain ourselves. This is an amazingly fast moving business!! –Processors double in speed every 18 months –The Internet doubles in size every year Computers are the most amazing and complex things ever built by mankind –The Intel Pentium III has 28 million transistors –It runs at 1.3 billion cycles per second COCO is about: 1. Computer building blocks 2. How the building blocks are assembled to build the computer

5. 4 Sheer Complexity 28 million transistors 1.3 billion cycles/sec clock Just one part of a computer Overall, a computer can have a billion transistors. Intel Pentium III Chip The Design Process is a systematic way to cope with all this complexity.

6. 5 Basic Ideas To design is to represent Divide and conquer Successive Refinement Use Math Tools: Combinational Logic Sequential Logic Use Software tools

7. 6 Traffic Signal Example N S E W N - S E - W Lights for N & S are the same, call them N-S Similarly, we have E-W

8. 7 What the System Does Cycles through the sequence GREEN-YELLOW-RED N-S and E-W never GREEN or YELLOW at the same time GREEN stays on for 45 seconds, YELLOW for 15, RED for 60 N S E W N - S E - W

9. 8 System Requirements speed: compute changes in under 100 ms power: consume less than 20 watts board area: implementation in less than 20 square cm cost: less than $20 in manufacturing costs N S E W N - S E - W

10. 9 "To Design Is to Represent" 1. English language specification not precise and subject to ambiguity 2. Functional description more precise flow charts, program fragments 3. Structural description modules decomposed into simpler components 4. Physical description In terms of logic gates or transistors Start after 45 seconds after 15 seconds after 45 seconds after 15 seconds N-S Red E-WYellow N-S Red E-W Green N-SYellow E-W Red N-S Green E-W Red

11. 10 Going from One Representation to Another Top Down: Complex functions replaced by more primitive functions Bottom Up: Build more and more complex assemblies out of smaller parts, respecting the rules of composition Rules of Composition: Electrical Rules Timing Rules

12. 11 Traffic Subsystem Start N-S Green E-W Red N-S Yellow N-S Red E-W Green E-W Yellow 45 secs Timer Start Light Sequencer 15 secs N-S Green E-W Red N-S Yellow N-S Red E-W Green E-W Yellow Start Timer 15 secs N-S Lights E-W Lights Counter 45 secs Decoder N-S Green E-W Red N-S Yellow N-S Red E-W Green E-W Yellow Top-Down Design Example Refine Refine again

13. 12 Exercise VARIATION to the basic traffic controller Add a left-turn arrow, but only in the direction of drivers facing North from South. (They wish to make left turns from South to West.) The green arrow should be on for 15 seconds while the lights are red for East-West and for South facing traffic. The drivers facing North see the sequence: green arrow (15s), green (45s), yellow (15s), red (60s), and repeat. From this specification, you should be able to determine the light timings for the other three directions. A. Make reasonable assumptions (be sure to state them clearly) about the duration of lights if not otherwise specified. B. Develop a flowchart for this controller. Answer

14. 13 Exercise Answers A.Make reasonable assumptions (be sure to state them clearly) about the duration of lights if not otherwise specified. Left-turn ON and N Green overlap  S Red. B.Develop a flowchart for this controller. Turn is ON N Green S Red E-W Red Turn is OFF N-S Green E-W Red Turn is OFF N-S Yellow E-W Red Start Turn is OFF N-S Red E-W Green Turn is OFF N-S Red E-W Yellow after 15 seconds after 30 seconds after 45 seconds after 15 seconds

15. 14 The Process of Building Ex., a group of flip flops form a counter groups of gates form flip flops, timers, sequencers etc. a group of transistors form a gate Gates Transistors Modules System

16. 15 Representations & Technologies Word description Functional Description Blocks Waveforms Truth Tables Boolean Algebra Gates Transistors Rapid Prototyping Technologies Chip Design Computer Synthesis Tools Computer Simulation

17. 16 Debugging the System Design Flaws Implementation does not meet functional specification Logic design is incorrect (wrong function implemented) Implementation Flaws Individual modules function correctly but their compositions do not Misunderstanding of interface and timing behavior Wiring mistakes Component Flaws What Can Go Wrong Design Flaws Implementation Flaws

18. 17 Systematic testing Simulation before construction Use lab Instruments, e.g., Logic Analyzers Debugging Methods Divide and conquer

19. 18 Design Recap Of Design Process Design Initial concept: what is the function performed by the object? Constraints: How fast? How much area? How much cost? Refine abstract functional blocks into more concrete realizations Implementation Assemble primitives into more complex building blocks Composition via wiring Choose among alternatives to improve the design Debug Faulty systems: design flaws, composition flaws, component flaws Design to make debugging easier Hypothesis formation and troubleshooting skills Implementation Iteration Debug

20. 19 What did we cover ? Sec 1.1 in Randy Katz Textbook Be sure to read Sec 1.1, 1.2 and 1.3 in the textbook (omit sec 1.3.5-1.3.7, and Sec 1.4) This reading is necessary for getting points in the Studio Activity!

21. 20 In-class Quiz True or False? T F  Design involves going through a series of increasingly detailed representations of a basic specification.  The speed, power requirement, board area, cost of components are “constraints” on design.  The right sequence of building a system is to first implement, then design and then debug.  A functional representation describes the design in terms of primitive physical components.  The bottom-up design approach starts with a word specification and successively refines the design by replacing complex or abstract functions with simpler or primitive functions.  The rules of composition of design components are as important as the components themselves.