1. 1 Embedded Systems James M. Conrad

2. 2 Outline of Talk Definition of embedded systems (are they imbedded?) Embedded processors (microcontrollers vs. microprocessors) Real-Time Operating Systems (RTOS) Examples of embedded systems Current courses in Embedded Systems Conclusions Contact info

3. 3 Computers are Everywhere Q: Where are computers today? On your desktop (of course!) In your microwave oven Controlling automobiles In a Palm Pilot PDA In your pager In a cell phone In a Nintendo console In your Gameboy... Everywhere!

4. 4

5. 5 What is Embedded? EMBEDDED APPLICATIONS GENERAL PURPOSE Cloudy Line

6. 6 What is an Embedded System? A microprocessor based device which has: –Pre-defined, specific functions –Constrained resources (memory, power) –Application runs from ROM Computer purchased as part of some other piece of equipment: –Typically dedicated software (may be user-customizable) –Often replaces previously electromechanical components –Often no “real” keyboard –Often limited display or no general-purpose display device

7. 7 A Customer View Reduced Cost Increased Functionality Improved Performance Increased Overall Dependability

8. 8 Microprocessor performance increasing Microprocessor cost decreasing Growing markets More applications Greater functionality and complexity Need to reduce time to market Leverage technology resources Outsourcing to off-the-shelf solutions What is Driving Embedded System Growth?

9. 9 How Big is it? Embedded is the largest and fastest-growing part of the worldwide microprocessor industry Embedded is approximately 100% of worldwide unit volume in microprocessors Average of 30-40 processors per home in US –(only 5 are within the home PC) “Turley’s Law”: –“The amount of processing power on your person will double every 12 months Analysts say... –Embedded systems in over 90% of worldwide electronic devices –By 2010, there will be 10 times more embedded programmers than others

10. 10 Microcontroller vs. Microprocessor Microcontroller has peripherals for embedded interfacing and control –Analog –Non-logic level signals –Timing –Communications point to point network –Reliability and safety

11. 11 Designing a Microcontroller into a System Power supply Clock signal generator Reset controller Memory Digital interfacing Analog interfacing Communications

12. 12 Anatomy of an Embedded Project 2 Choose a processor 1 Application Requirements Choose an RTOS 3 pSOS+VxWorks Neutrino lynxOS nucleus

13. 13 4 Anatomy of an Embedded Project Often not an independent decision from RTOS Embedded Systems Buyers Guide lists > 50 compiler and > 50 debugger suppliers VDC report “Worldwide Market for Embedded Software…” analyzes market leaders Choose development tools - (compiler suite, debugger, simulator) MetroWerks

14. 14 Anatomy of an Embedded Project Platform Developers Application Developers Board support package Device drivers Hardware debug - JTAG, ICE Native development OS simulation or Eval platform “Code Centric” tools Integrate and Test Runtime analysis Advanced debug modes Code optimization 5

15. 15 Architecture of a Real-Time OS pSOSystem is modular, containing pSOS+Kernel plus a collection of selectable components and libraries User Application FTP Telnet DNS DHCP TCP/UDP/IP RCP NFS Shared Lib Mgr Loader File Systems C Run Time library POSIX Real Time Multitasking kernel Board Support Package (Boot code, Drivers, Configuration files) PPP NAT X.25

16. 16 Case Study – T68 Printed Circuit Board From Electronic Engineering Times, May 13, 2002, p. 30

17. 17 Case Study – T68 – Block Diagram From Electronic Engineering Times, May 13, 2002, p. 30

18. 18 Topics Taught in Embedded Systems Course Introduction to Embedded Systems and Microcontroller-based Circuit Design Renesas (Mitsubishi) 16C Instruction Set Architecture C Programming Review and Dissection The MSV30262-SKP Starter Kit and Tutorial Interrupts, C Start-Up Module and Simple Digital I/O Debugging Software and Hardware Algorithms and Software Design Using and Programming Interrupts in C Sharing Data and Interrupt-Driven Serial Communications Round-Robin Non-Preemptive Scheduler Analog to Digital Conversion Software Testing Processes Coordination and Simple Scheduling Scheduling and Watchdog Timers Memory Expansion and DMA Performance Analysis Creating an Embedded System Architecture

19. 19 Microcontroller Board Used in Course M16C/26 family of microcontrollers –M30262 Excellent development environment and tools come with the board –C++ compiler –Monitor Board –USB support Each student purchases, $50 a board

20. 20 Embedded Class Development Board

21. 21 Robotics - Stiquito

22. 22 Stiquito - What Is It? Invented by Jonathan Mills, CS Department, Indiana University, in 1992. Hexapod (six legs) Small - can sit on a credit card (75mm x 70mm x 25mm, 10g) Inexpensive ($5.00 in mass quantities), easy-to-build Can carry about 50g of weight Travels using a “Nitinol” muscle (also comprises 1/2 of the cost of the kit)

23. 23 Stiquito Books Stiquito tm : Advanced Experiments with a Simple and Inexpensive Robot, ISBN 0-8186-7408-3, IEEE Computer Society Press/Wiley, 1997. Stiquito tm for Beginners: An Introduction to Robotics, ISBN 0- 8186-7514-4, IEEE Computer Society Press/Wiley, 1999. Stiquito tm Controlled!, ISBN 0-4714-8882-8, IEEE Computer Society Press/Wiley, 2004. Book includes embedded board, shown at right.

24. 24 The Stiquito Robot Two books published by the IEEE CS Press show users how to build a low-cost robot Books include the materials to build the “Stiquito” robot body. The books describes how to build circuits to control the hexapod robot, but do not include the materials to build the control circuits. The ideal book would also include a circuit board INSIDE the book to make the robot walk. A third book, Stiquito Controlled!, will include instructions for making a life-like walking insect robot using the TI430 microcontroller.

25. 25 Embedded System - Robot Robotics relies on one or more microprocessors/ microcontrollers for full closed-loop operation: –Sense the environment (i.e. bump, sonar, light) –Make decisions based on input –Control the robot and devices (i.e. drive system, radio) The Stiquito Controller Board is open-loop – there is no sensing. Supports one and two degree-of-freedom operation (forward/back versus both forward/back and up/down) Expandable – can add other components and programming interface

26. 26 Schematic of Stiquito Controller Board

27. 27 Design Decisions The MSP430F1122 (flash variant) selected based on functionality and cost. The board circuit also includes an ULN2803 Darlington Transistor array to drive current through the robot’s “muscles” (nitinol). The board also contains some LEDs which indicate power-on and muscle “contraction”. The board was designed with expandability in mind: a JTAG port was put on the PCB, and a prototyping area with through holes was added to the front of the robot.

28. 28 Stiquito as an Embedded System The board in the book will be pre-programmed during the manufacturing process. The board will make the robot walk in a normal fashion without any user programming. Advanced users can solder the JTAG port onto the board and, using a JTAG interface cable, download new code, thus making the board and robot an experimental platform. The book and accompanying robot (with controller) will be an excellent educational device, and would not have been possible with the full-functioned yet inexpensive MSP430 family of microcontrollers.

29. 29 Wireless Research

30. 30 Research Overview  Adaptive Antennas  Performance analysis  Optimization strategies  UL band data communication  Exploit current RF devices  IEEE 802.11  Bluetooth  IEEE 802.15.4  Optimizing AP Location  Bandwidth Tradeoffs range vs. data rate vs. reliability  DSSS Detection  Synchronization  Multi User Detection (MUD) Wireless Environment  UL Band Coexistence  Analysis Methodology  Mitigation Techniques  Optimizing Network(s) Performance

31. 31 Application Design Considerations Enabling Application with UL Band Wireless Device Wireless Design Solutions Wireless Standards Application Requirements Implementation Environment Coexistence Issues

32. 32 Coexistence Summary  Method for Evaluating & Understanding Coexistence  Bluetooth & 802.11b  Arbitrary  Communication Network  RF Scenario  Identify Scenarios Where Coexistence is Impacted  Methods for Mitigating  Site Specific Analysis  Straight Forward Extension to Evaluate other WPANs & WLANs

33. 33 Embedded Wireless Research Test Bed IEEE 802.15.4 (Zigbee) is an open specification for short-range radio technology that enables wireless data communication between devices. The 802.15.4 standard was created to further reduce power consumption from typical Bluetooth devices. 802.15.4 devices have a maximum of 20 kbits per second in the 868 MHz frequency band and 250 kbits per second in the 2.4 MHz frequency band. Faculty are building competencies in 802.15.4 for use in an array of applications, including wireless sensor networks. Applications include wireless transmission of sensed data in geological, environmental, or mechanical precision measurement systems.

34. 34 Embedded Wireless Research Test Bed First deliverable item for this research is an embedded wireless communications test bed that can be used for future research activities.

35. 35 Material Borrowed for this Presentation These slides, pictures, etc. have come from many sources, too numerous to list fully, but including: Jim Turley (www.jimturley.com) Alex Dean (NCSU ECE 306 notes) Embedded Systems Programming Magazine (www.embedded.com) David Stepner, Integrated Systems, Inc. Mitsubishi/Renesas Electronic Engineering Times

36. 36 Contact Information James M. Conrad Associate Professor Dept. of Electrical and Computer Engineering UNC-Charlotte 9201 University City Boulevard Charlotte, NC 28223, USA jmconrad@uncc.edu* http://www.ece.uncc.edu/~jmconrad Phone: +1-704-687-2535 Fax: +1-704-687-2352 * Preferred method of contact