10 Aug 2010

ECE/BENG-492 SENIOR ADVANCED

DESIGN PROJECTMeeting #5

ECE-492 Meeting#5ECE-492 Meeting#5

Q1: Teams – show draft diagrams of your system architecture

Q2: Any questions about proposal format and preparation?

System Design II:Behavioral ModelsSystem Design II:Behavioral Models

• A system model is needed for describing system behavior, with an emphasis on computing resources and other resources influencing system functionality

• Models are needed to describe:– Interactivity of a system with the environment

– Man-machine interactions – how to operate a system

– Interactivity between modules – signal/data exchange, actions, etc.

• Models can be used to describe system behavior at any level

• You need to work with these models to avoid disasters !

• They are also planning tools for your team

• ‘Model’ – we mean a hard copy so you and your team can see it on paper– Models in your mind. . . leave for your hobbies. . .

– A hard copy is a must:

• To have a blueprint of system behavior,

• To transfer your mathematical model into its implementation

• To coordinate your implementation activities around these behaviors, and

• To be able to trace it if problems occur --- and they will !!!

ModelsModels

• State Diagrams (State Machine)– State diagrams describe the behavior of systems with memory

– Intuitively, a state corresponds to an operating mode of a system and inputs are associated with transitions between states

– Almost all systems are systems with memory – consider startup phase, work phase, turn-off phase, sleep phase, etc.

– Show transitions between states/phases using state diagrams

– A must for systems with microcontrollers

– Excellent tool to visualize control influences for systems controlled by a microprocessor

– Mostly used at the upper abstraction level

– Again, you have to use them when programming microcontrollers – will help you to define tasks and task switching mechanisms

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• Flowcharts– The intention is to visually describe a process or algorithm; for

example data/signal processing

– Used to connect activities of a process or algorithm together

– You can use flowcharts to describe processes at different levels of detail within each state

• Data Flow Diagrams– Used to model the processing and flow of data inside a system

– A function oriented modeling approach

– Differs from Flowcharts – it does not encapsulate control and sequencing information, but allows multiple processes running concurrently

– See Chapter 6

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CASE STUDY#1

< State Diagram >

CASE STUDY#1

< State Diagram >

Modeling and Design Design + Mathematical model System implementation

Modeling and Design Design + Mathematical model System implementation

• Many ECE 492/3 projects include a control component

• If you have a control element in your system, then review control engineering principles

• Proper design, modeling and implementation is still a challenging issue for EE and CpE students RIGH vs. WRONG

System Model(math+physics)

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Performance prediction + Parameters

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Structure + Parameter Modifications

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Design evaluation

Simulation

Mathematical Modeling and System ControlMathematical Modeling and System Control

• Use functional/physical decomposition to determine system structure

• Assign mathematical equation(s) to each physical/functional element (this will help you to handle complexity and allow for easier implementation and debugging)

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• Use simulation

• System debugging will be simpler and conclusions for system modification will be more clear

• You will estimate system parameters much faster meaning: no endless experimentation and debugging

• Recommendations: Use simple equation(s) to represent each system component Check simulation results:

Are your results LOGICAL ?Are they VALID ?Can you EXPLAIN what happens in your system ?

Keep it simple, complicate later when you succeed

Early PrototypingEarly Prototyping

• Early prototyping is absolutely needed to– Understand chips/components you will work with (these days

many chips are multifunctional with inherited complications)

– Check them against spec

– Play to educate yourself and gain experience

• Right after proposal presentation, you need to define key chips/elements you will use in your design/system – you need to buy them early and work with them immediately

• Early prototyping report is needed at your Design Review Presentation (Week#11)

• You will eventually need to extend early prototyping over the first 1-2 weeks of ECE-493, if needed, but no longer than that

Proposal PresentationProposal Presentation

• Limit your presentation to 20-30 minutes

• You must have two faculty members at the presentation

• All team members must speak at the proposal presentation – distribute the load evenly, but do not switch speakers too frequently

• Your presentation must be professional– It matters what you wear

– Use audio-visual equipment

– Distribute a copy of your proposal and slides before the presentation day (coordinate with FS)

– Use right size font and nice figures

• Book the room and find another faculty in advance

Preparing for the PresentationPreparing for the Presentation

• Before you start developing the presentation, plan your strategy. Design it! You are telling the story!!!

• Analyze your audience - it’s the audience stupid!– What are they interested in?

– What do they want from your talk?

– What does the audience know? What don’t they know?

• Determine main points– Emphasize 2-3 main points in your talk

– Structure your presentation to support these points

– Remember, ‘tell your story’

Sample Presentation ContentSample Presentation Content

• Follow your proposal content• Introduction/motivation and identification of a need• Main technical body including

– Requirements– System architecture– Alternative designs (any other you considered?)– Identify main components and their role. How about interfaces?– What are major challenges?– Experimentation and testing approach

• Main administrative body– List of tasks and allocation of responsibilities– Skills of team members. What is an extra knowledge/skills to be

acquired?

• Conclusions

Extra AdviceExtra Advice

• Use professionally prepared graphics• Do not use PowerPoint “CPU Wasters” (extra visual

effects, fancy combinations of them)• Avoid the use of cue cards – read directly from slides• Meet the time constraints through the entire talk – have

control points• Motivate your audience to listen. Stay excited.• Practice your talk in front of your teammates, girlfriend/

boyfriend, family members• Do not overprepare to the point of sounded scripted• Practice the talk a night before, and do only a brief

review of the material right before the talk• You can tell a joke but watch out the ethics, etc.• Prepare for the question and answer session

For the Next MeetingFor the Next Meeting

• Read textbook – Chapters 6 and 12

• Teams – bring a state diagram showing state transition of your system at Level-1 (or Flowchart, Data flow diagram)

• Next meeting:– Design document; Design Review presentation