1. Prof. John Nestor ECE Department Lafayette College Easton, Pennsylvania 18042 nestorj@lafayette.edu ECE 491 - Senior Design I Lecture 12 - System Design & Project Mgt. Fall 2006 Reading: S&R Ch.4 - System Design S&R Ch. 5 - Project Management Colwell Ch. 2 - The Concept Phase Colwell Ch. 3 - The Refinement Phase

2. ECE 491 Fall 2006Lecture 12 - System Design2 Where we are  Last Time:  Timing  Metastability  Today:  System Design  Project Management  P6 System Design / Project Management

3. ECE 491 Fall 2006Lecture 12 - System Design3 Review: S&R Design Methodology  Requirements analysis  Creating a detailed problem specification  Defining what is needed for completion  System Design  Determine “how problem will be solved”  Create a system specification that describes design at a functional level  Result: System specification  Detailed Design  Create designs for blocks in system design  Debug and verify individual blocks  System Integration and Test  Combine design blocks  Test complete system Customer needing solution to a problem Properly functioning system S&R Figure 2.4 Requirements analysis System design Detailed design System Integration And Test

4. ECE 491 Fall 2006Lecture 12 - System Design4 The System Design Process S&R Figure 4.4 Development of Concepts Analysis Synthesis Requirements Specification System Specification Reject Unworkable Concepts

5. ECE 491 Fall 2006Lecture 12 - System Design5 Key Steps - Conceptualization  Goal - develop “hazy perception of a solution”  Sources of concepts  Draw from solutions to similar problems  Come up with original solution based on prior experience  Brainstorming sessions - see Colwell Ch. 2

6. ECE 491 Fall 2006Lecture 12 - System Design6 Key Steps - Synthesis  Goal - “bring structure to the initial concept”; provide detail needed for analysis & implementation  Block diagram as the key  Start out with a “rough sketch”  Add detail as design proceeds  Refine as design proceeds

7. ECE 491 Fall 2006Lecture 12 - System Design7 Block Diagram Guidelines  Each block should be implementable with a single technology  Common functions should be grouped into one block  Blocks should be defined to simplify interfaces  Avoid feedback loops if possible  Specify assertion levels in digital interfaces  Specify characteristics (e.g., impedance, frequency) of analog & RF interfaces  Anticipate difficulty in timing and sequencing of interface signals

8. ECE 491 Fall 2006Lecture 12 - System Design8 Example - Flicker Analyzer  Initial Block Diagram Voltage divider by 75 Anti- aliasing filter  2.5 8-bit A/D converter Oscillator 200 Hz square clock for sampling RS 232 19.2 kbps no parity To the serial port of the PC Ground Common Chassis S&R Figure 4.8 A/D input range Is 0 to 5 volts Between +/- 2.5 Neutral v(t)

9. ECE 491 Fall 2006Lecture 12 - System Design9 Example - Flicker Analyzer  Refined Block Diagram Voltage divider 75 +/-.5% Anti- aliasing filter 1 +/-.5%  2.5 +/- 0.18 16-bit A/D converter Oscillator 200 Hz square clock for sampling RS 232 3 bytes per sample Ground Common Chassis S&R Figure 4.9 16-bit bus 16-bit A/D converter Neutral v(t)

10. ECE 491 Fall 2006Lecture 12 - System Design10 Key Steps - Analysis  Goal - determine if synthesized system will meet performance and cost objectives  Secondary goal - determine risk of completing design  Tools for analysis  Mathematical models  Simulations - Verilog, Matlab, Simulink, etc.  Lab-based prototype

11. ECE 491 Fall 2006Lecture 12 - System Design11 End Product - The System Specification  Summary of the Concept  Annotated Block Diagram, I/O specification  Functional descriptions of blocks  System description  System analysis - results of analysis, simulation, measurements

12. ECE 491 Fall 2006Lecture 12 - System Design12 System Design on the P6  A Data-Driven Culture  The problem: intuition is often wrong and differs widely between engineers  The solution: design and conduct small experiments and collect data about issue in question  A tradeoff  Too much analysis will impede progress  Too little will result in a poor design

13. ECE 491 Fall 2006Lecture 12 - System Design13 P6 Analysis Tools  The Data Flow Analyzer (DFA) - a tool to evaulate parallelism  Input: execution traces, constraints  Output: expected speedup  RTL Simulator

14. ECE 491 Fall 2006Lecture 12 - System Design14 Project Management - What is a Project?  Quantifiable piece of work  Defined start and end  Expectation of specific outputs and deliverables  Measurable objectives  Limited Resources (people, materials, equipment)  Often complex, uncertain, and/or urgent

15. ECE 491 Fall 2006Lecture 12 - System Design15 Elements of Project Management  Planning  Define work to be done  Develop schedule to complete work  Develop budget  Specify needed resources (materials, people, equipment)  Monitoring  Keep track of project  Determine whether deadlines will be met  Control  Shift resources between tasks  Modify plan to optimize progress

16. ECE 491 Fall 2006Lecture 12 - System Design16 The Project Plan  Definition of Work  Schedule  Resource requirements  Cost estimate

17. ECE 491 Fall 2006Lecture 12 - System Design17 S&R Fig. 5.2 The Planning Process System design Detailed design Preliminary plan Define work Develop schedule Estimate resources Estimate costs Design Mgt. Project plan Design ProcessPlanning Process

18. ECE 491 Fall 2006Lecture 12 - System Design18 Definition of Work  Use system design, block diagram as info source  Develop a list of tasks to be completed  Describe the deliverables of each task  Document any needed inputs  Specify completion date needed (“milestone”)  Estimate duration  Estimate resources needed  Determine precedence w.r.t. other tasks  Example: See S&R Tables 5.1 - 5.3

19. ECE 491 Fall 2006Lecture 12 - System Design19 Scheduling  Goal: determine order in which tasks are performed  Scheduling diagrams  Network diagrams  Bar Charts (Gantt Charts)

20. ECE 491 Fall 2006Lecture 12 - System Design20 Network Diagram  Activity on Arrow (AOA) 03789.51 System Design (3) Power supply (1) Main board (4) Packaging (3) Integrate and test(1) Finalize (1.5) Prototype (1.5) EndStart S&R Fig. 5.4

21. ECE 491 Fall 2006Lecture 12 - System Design21 Network Diagrams  Activity on Node (AON) 1.03.0 System Design 003 3.02.5 Pwr supply 33.04 5.01.0 Integrate & Test 708 6.01.5 Finalize 809.5 7.01.5 Prototype 9.5011 4.03.0 Packaging 31.06 2.04.0 Main board 307 8.011.0 Packaging 0011 Task no.Elapsed Time. Start Week Slack Time End Week S&R Fig. 5.5

22. ECE 491 Fall 2006Lecture 12 - System Design22 Bar Charts (Gantt Charts) 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 System design Main board design Power supply design Packaging design Integrate & test Finalize design Construct prototypes Project management 010815222906132027031017 01 Start Finalize System Design Complete Acceptance Test Design Signoff End S&R Fig. 5.7

23. ECE 491 Fall 2006Lecture 12 - System Design23 Scheduling Tools  Microsoft Project  Primavera  GanttProject – Open Source Java program (available at ganttproject.sourceforge.net)

24. ECE 491 Fall 2006Lecture 12 - System Design24 GanttProject - Gantt Chart View

25. ECE 491 Fall 2006Lecture 12 - System Design25 GanttProject - Network Diagram View

26. ECE 491 Fall 2006Lecture 12 - System Design26 Cost Estimation  Personnel  Direct costs - Wages  Indirect costs (Overhead) – Benefits, facilities costs, supporting departments, etc.  Lab, shop, and other internal facilities  Outside services and facilities  Supplies and materials  More details in S&R Section 5.5

27. ECE 491 Fall 2006Lecture 12 - System Design27 Managing a Project  Performance Monitoring  Task Progress  Schedule Status  Budget Status  Reporting

28. ECE 491 Fall 2006Lecture 12 - System Design28 P6 Project Management  Organizing a team:  Make assignments to exploit strengths of each individual Put best engineers on “most difficult” parts of design Assign jobs based to give individual best “leverage”  Provide leadership for new hires

29. ECE 491 Fall 2006Lecture 12 - System Design29 P6 Design Team - Organization Colwell Fig. 2.3, p. 36

30. ECE 491 Fall 2006Lecture 12 - System Design30 P6 Verification - “Presilicon Validation”  Goal: test RTL model as it becomes available  Ideal: “keep presilicon validation separate from, but embedded within, design team”  Challenge: validators get “absorbed” as designers  Approach:  Module designers write basic “unit tests”  Require “at least minimal” testing before release  When integrating modules into larger units, debug using the “bigger wizard” approach

31. ECE 491 Fall 2006Lecture 12 - System Design31 P6 Organization - Additional Notes  The importance of physical proximity  Place designers working on same unit in adjacent cubicles  Place design groups on adjacent units nearby - cubicle floorplan mimics chip floorplan!  Place architects in center to avoid “us vs. them”  Bad idea: separating architects into a long-range R&D group

32. ECE 491 Fall 2006Lecture 12 - System Design32 Coming Up  Data Communications (cont’d)  RS-232 Receiver Design  Manchester Code  Ethernet  Detailed Design