Embedded System Design - Chapter 2: Develop a project of embedded system design

Nội dung text: Embedded System Design - Chapter 2: Develop a project of embedded system design

1. 8/12/2016 ĐẠ I H ỌC QU ỐC GIA TP.H Ồ CHÍ MINH TR ƯỜ NG ĐẠ I H ỌC BÁCH KHOA KHOA ĐIỆN-ĐIỆN T Ử BỘ MÔN K Ỹ THU ẬT ĐIỆN T Ử Embedded System Design Chapter 2: Develop a project of embedded system design 1. Design Process 2. Design Issues 3. Technology selection 4. Project plan 1 1. Embedded System Design Process • Several models can be applied for embedded system design – The waterfall model : in which there is a process for developing a system in steps, where results of one step flow into the next step. – The spiral model : in which there is a process for developing a system in steps, and throughout the various steps, feedback is obtained and incorporated back into the process. – Consecutive refinement model • Most followed and simple model for building an Embedded System is Waterfall model Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 2 Chapter 2 1
2. 8/12/2016 1.1. System Specification 1. Product Specification: – What the system is to do – What the user interface is – What the real world I/O consists of – What the external interface to other system is (if any) – What are the constraints? (speed, stability, low power, cost ) • Example: Oven temperature control system – Functions: control the heater and the fan of an oven – I/O: temperature sensor, heater port, fan port – User interface: LCD display, keypad – External interface: UART Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 5 1.1. System Specification 2. Engineering Specification: – What kind of hardware will be used – What are the requirements for hardware and software • Example: Oven temperature control system – 8051 microcontroller, LM35 sensor, LCD 16x2-B, ADC0809, RS232 IC – Requirements • PID control algorithm • real-time processing • Display current temperature value • able to set operating temperature value • Transfer data to computer through UART Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 6 Chapter 2 3
3. 8/12/2016 1.1. System Specification 5. Test Specification: – The device, equipment, environment for testing – Prototype – Testing process • Example: Oven temperature control system – Voltage meter, temperature meter – Prototype: bread board – Testing process: • calibrate temperature sensor • check LCD, keypad • check output port (heater, fan) • verify PID control algorithm Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 9 1.1. System Specification • Group discussion – Write a specification document for your own class project Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 10 Chapter 2 5
4. 8/12/2016 1.2. System partitioning • Group discussion – Apply system partitioning for your own class project Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 13 2. Embedded System Design Issues • Design issues are problems that make it difficult to design an embedded system 1. Constraint issues – cost may matter more than speed – long life cycle – Reliability/safety – Low-power – Size / weight Examples: Portable heart-beat monitor – Long life cycle (10 years) – Reliability (accuracy 99%) – Low-power (5 using days) – Light weight (<1kg) Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 1 14 Chapter 2 7
5. 8/12/2016 2. Embedded System Design Issues 2. Functional issues Examples for battery charger No. Issues Note 1 Battery can be over-heat, it need to be detected by a Correct sensor 2 Display a charging current and battery status Wrong 3 The system must have a fuse for protection of over ? current 4 Support 3 charging modes ? 5 Apply efficient algorithm for fast charging and increase ? battery life cycle Functional issues are problems which can affect to life, health, economy, environment, society, politics, ethics. Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 1 17 2. Embedded System Design Issues 3. Real-time issues – Determine whether the system is hard/soft/non real-time – Determine the time constraint (delay) Example • Door entry alarm – Non/soft real-time system: delay < 1-2s • Video recorder – Soft real-time system: delay < 1ms • Car airbag system – ? • Weather temperature monitoring – ? Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 1 18 Chapter 2 9
6. 8/12/2016 2. Embedded System Design Issues • Group discussion – Discuss about design issues of your own class project Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 1 21 3. Technology Selection • Technology – A manner of accomplishing a task, especially using technical processes, methods, or knowledge • Three key technologies for embedded systems – Processor technologies: general-purpose, application- specific, single-purpose – IC technologies: Full-custom, semi-custom, PLD – Design technologies: Compilation/synthesis, libraries/IP, test/verification 22 Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 Chapter 2 11
7. 8/12/2016 IC technology • The manner in which a digital (gate-level) implementation is mapped onto an IC – IC: Integrated circuit, or “chip” – IC technologies differ in their customization to a design – IC’s consist of numerous layers (perhaps 10 or more) • IC technologies differ with respect to who builds each layer and when gate IC package IC oxide source channel drain Silicon substrate 25 Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 Design technology • Compilation/synthesis: – C Compilers: CCS C, mikro C, Keil C, Code Composer Studio, • Libraries/IP – Stellarisware, Tivaware, STM32 Library, – OS: Embedded Linux, RTOS • Test/verification – Development kits – Simulation tools: Proteus, Orcad, PSIM 26 Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 Chapter 2 13
8. 8/12/2016 Team Contract TEAM CONTRACT Team name: BK1 Date: 26 Aug. 2014 Team member Roles Signature Nguyễn Văn A Leader, system engineer Trần Văn B Hardware design Nguyễn Thị C Software design Tasks Responsible member 1. Develop system architecture Nguyễn Văn A 2. Design hardware Trần Văn B 3. Develop software Nguyễn Thị C 4. Integrate and test All Team meeting 9AM, Wednesday, weekly Team rules 1. Participate in all team meetings 2. Listen carefully to all comments at meetings 3. Complete all assigned tasks before deadlines 4. Focus on results rather than excuses after. Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 29 Build a plan • Project planning activities Identify the task Develop Develop Estimate teams schedule time Plan tasks Refine plan Approve Cancel plan plan Proceed plan Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 30 Chapter 2 15
9. 8/12/2016 Class assignment • Design a embedded system for washing machine No. Specification Describe 1 Product -Washing process: soak, wash, rinse, spin specification -Mode: manual, fuzzy -Constraints 2 Engineering -Inputs: specification -Outputs: -Use interface: 3 Hardware -Microcontroller: specification -Sensors: -Actuators: 4 Software -Functions: specification -Control algorithm: 5 Test -Platform: specification -Test process: Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 33 Group discussion 1. Consider the project car’s door mechanism Write system specification for this project Bộ môn Kỹ Thu ật Điện Tử - ĐHBK Chapter 2 34 Chapter 2 17