FACULTY OF AUTOMATION AND COMPUTER SCIENCE. Eng. Silviu-Corneliu FOLEA. PhD THESIS

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1 FACULTY OF AUTOMATION AND COMPUTER SCIENCE Eng. Silviu-Corneliu FOLEA PhD THESIS DEVELOPMENT OF EMBEDDED SYSTEMS FOR INTEGRATION WITH GRAPHICAL PROGRAMMING ABSTRACT THESIS ADVISOR: Prof. dr. Eng. Tiberiu COLOŞI

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3 Eng. Silviu-Corneliu FOLEA Technical University of Cluj-Napoca Faculty of Automation and Computer Science Cluj-Napoca, Bariţiu 26 Street, Romania Tel: Development of Embedded Systems for Integration with Graphical Programming PhD Student: eng. Silviu-Corneliu FOLEA Thesis advisor: Prof. dr. eng. Tiberiu COLOŞI 1. Contents Foreword...2 List of abbreviations...7 Introduction...10 Part I...12 Chapter 1. Embedded systems in process control applications Definition of acquisition interface concept Embedded system types SBC cards CompactPCI standard PC/104 standard PLC LabVIEW virtual instrumentation environment Virtual instrument definition LabVIEW integration state of the art Architecture of real time virtual instrumentation LabVIEW Real Time environment New solutions. LabVIEW on embedded systems Data acquisition system through Ethernet HUB Ethernet for data nodes management and radio data acquisition Flexible data acquisition system...29 Chapter 2. Digital control structures and interface specific mathematics Classification of digital control structures Direct digital control structure Supervised control structure Hierarchical multi layered control structure Hierarchical multi leveled control structure Distributed control structure Future of digital control Mathematics for specialized interfaces Discretization methods Mathematical models

4 PhD Thesis - Development of Embedded Systems for Integration with Graphical Programming Performance criteria Primary signal processing methods Measurement pre-filtering Numerical control algorithms Other aspects of digital control Part II Chapter 3. Data acquisition system over Ethernet The problem Current solution analysis Evaluation of current solution Requirements or optimal solution specification The optimal solution General structure of the system The novelty of proposed solution Design exceptions Specifications and achieved performances LabVIEW integration method for this platform Future development AT91FR4081 processor based module, with analog and digital interface Hardware description Motivation for using ecos operating system AT91FR4081 processor programming module with AT89S8252 microcontroller LabVIEW Matchbox, concept Generic module based on AT91FR4081 processor for interfacing with analog and digital input/output cards, with serial SPI interface Application example, temperature control. LabVIEW implementation Choosing the application Block diagram of the control system Temperature measurement using LM35 integrated sensor Front panel of the application and block diagram Performance, experimental results Conclusion Chapter 4. HUB Ethernet for data nodes management The problem Current solution analysis Evaluation of current solution Requirements or optimal solution specification The optimal solution General structure of the system The novelty of proposed solution Design exceptions Specifications and achieved performances LabVIEW RT integration method for this platform integral Future development HUB Ethernet, data node based on CS89712 processor Hardware description Alternative solution based on MachZ processor, 486DX 133 MHz How to install Linux operating system on ARM Analog and digital input/outputs based on AduC824 microcontroller

5 Module with 2 analog inputs for thermocouples, analog output and DIO Module with voltage analog input, analog output, timer/counter and DIO Module with 2 analog inputs for PT100 and DIO Module with 4 digital open collector outputs 24V, 100mA and DIO Module with voltage analog input and 4 DIO Radio communication architecture and protocol Radio communication modules Radio transceiver Lynx TR-916-SC Radio transceiver TR MaxStream, radio module with frequency hopping Radio protocol proposal The monitoring application for radio acquisition module. LabVIEW implementation Choosing the application Configuring the application Front panel of the application and block diagram Performances, experimental results Conclusion...98 Chapter 5. Flexible data acquisition system The problem Analysis of existing solutions Evaluation of existing solutions Requirements or optimal solution specification The optimal solution General structure of the system Specifications and performances Design exceptions The novelty of proposed solution Future development Access point and data node based on PXA250 processor Hardware architecture of the Wireless DAQ microsystem Software architecture of the Wireless DAQ microsystem PCMCIA slot extension possibilities Data acquisition module based on C8051F124 microcontroller Choosing the application Performances, experimental results Conclusion Temperature and 2 axis acceleration measurement module with AT91FR40162 processor Hardware architecture of LabVIEW Stamp microsystem Software architecture of LabVIEW Stamp microsystem Loading a VI into LabVIEW Stamp Runtime communication Applications. Acceleration and temperature monitoring Performances, experimental results Conclusion Access point and data node based on PXA255 processor Extension solution for 2 CF slots and one MMS Compact Flash data acquisition interface

6 PhD Thesis - Development of Embedded Systems for Integration with Graphical Programming 5.6. The modular microsystem AT91FR40162 processor based module Power and battery charger module Dual serial RS232 module Analog and digital input/output module MMC extension module Bluetooth communication module Debug module with LEDs Breadboard module Extension solution. Other applicable modules Power consumption LabVIEW Embedded integration solution for this platform Applications. LabVIEW Embedded and LVRT implementation Choosing the applications Acceleration and vibration measurement with the modular microsystem MP3 file player with the modular microsystem MP3 file player with the PDA and DAQCF acquisition card Miniature car control through Bluetooth with the modular microsystem Distributed acquisition with modular microsystems Generating signals with a PDA and DAQCF acquisition card Data acquisition with PXA255 based microsystem and DAQCF Performances, experimental results Conclusion Chapter 6. Contribution of the author and future research paths Original contribution of the author Other achievements during the research Future research paths Development tendencies of digital computation and data acquisition systems integrators Selective Bibliography LabVIEW on Small Target Modular Embedded System Contents Keywords Thesis outline RESUME List of most significant work and brevets Keywords Embedded systems, virtual instrumentation, LabVIEW graphical programming environment, analog and digital data acquisition, analog to digital and digital to analog converter, operating systems, microcontrollers, microprocessors, SDRAM and flash memory, 4

7 wireless Ethernet, Bluetooth, IrDA, distributed systems, modularization, portables, low power consumption, MEMS. 3. Thesis outline The main objectives of the thesis are: study of the embedded systems and methods for programming them directly from a graphical environment, particularly from LabVIEW, design and implementation of embedded systems, as well as integration of applications written for personal computers into these microsystems. Achieving these targets, more than theoretically, implies support from the companies involved in virtual instrumentation software development. In this case the support came from National Instruments USA, and therefore the virtual instrumentation environment was LabVIEW. The systems designed in this work are specialized interfaces for analog and digital data acquisition, input/output, data processors, with support for direct LabVIEW programming. These interfaces have the following features: - direct programming and control from LabVIEW; o program development in LabVIEW (Virtual Instruments - VIs); o program upload from the PC directly to the embedded system; o visualization of data from the embedded system on the VI's front panel on the PC, given that the application runs on the embedded system; o use of analysis functions from LabVIEW; - modular systems, allowing a wide range of configurations, without the need of redesigning the interfaces, only by reuse of the existing modules; o implementation of hardware level configurable equipment, enabling the user to connect the modules so that the result gets as close as possible to the requirements; o Design based on newest integrated circuit technology, enabling production of prototypes; o reconfigurable; o interchangeable; - Highest possible computational power on processing modules; - wide range of communication types: RS232/RS485 serial communication, wired Ethernet, radio modems, wireless b Ethernet or Bluetooth, IrDA; o comparison of several communication media based on the results obtained from their use; o analysis of required resources for each of the communication types; - low power consumption; - mobility, battery powered for long periods; - comparative analysis of methods for porting a graphical programming environment from the PC to microsystems (non-pc); - low cost devices, with prices as low as a classical controller, adaptor or communication module. All embedded systems presented in chapters 3, 4 and 5 were designed by the author: schematics were designed in OrCAD, component lists and product codes were gathered for buying the components, PCB layouts were designed based on specifications, Gerber and Centroid files were generated for making the PCB and mounting the components, test programs were written and debug was made on the faulty circuits. 5

8 PhD Thesis - Development of Embedded Systems for Integration with Graphical Programming Resulted microsystems and software are object of five USA patents; the author is member on two of them. The thesis has two parts and has six chapters, as follows: The first part of the thesis is a bibliographical study. It is comprised in Chapters 1 and 2 and represents an overview of acquisition interfaces and embedded systems. Chapter 1 presents a survey of embedded systems like: SBC, CompactPCI, PC104, PLC, VXI and PXI special computers. A short definition of the virtual instrument is given, as well as a short presentation of LabVIEW virtual instrumentation environment and the current levels of LabVIEW integration are indicated. The chapter also comprises a short presentation of LabVIEW Real Time and its applications as a point for comparison to nowadays utilization due to the solutions given in this thesis. Chapter 2 gives a classification of typical implementable digital control structures: direct, supervised, hierarchical with multiple layers, hierarchical with multiple levels, distributed, structures that can be implemented successfully using the embedded systems presented in this work, a future for digital control. This chapter also contains a set of specialized interfaces mathematical formalisms like: discretisation methods, primary signal processing methods, filtration of measured variable, digital control algorithms and other aspects of digital control. Most of these formalisms were used in applications' development. Research results on LabVIEW programmable embedded systems are comprised in Chapters 3, 4 and 5. Target applications that require such interfaces are: autonomous mobile robots, portable measurement devices, portable medical devices, autonomous weather stations, satellite communication devices, military systems, supervisory and control systems. Chapter 3 presents the Ethernet Data Acquisition System (EDAS). This is a microsystem with high computational power for its category, allowing long distance monitoring and local control of real systems (Figure 1). This application was presented at NI- Week 2002 (Technical International Conference that takes place in Austin, Texas, under supervision of National Instruments USA). Figure 1. General structure of EDAS system 6

9 EDAS systems are Ethernet enabled data acquisition cards designed for real process monitoring (Figure 2. a). Due to its ecos real time operating system, EDAS can not only run monitoring tasks but also local control loops with parameters adjustable through Ethernet connection. The system has TCP/IP connection, runs ecos real time operating system ensuring quick, parallel and prioritized execution. The reduced dimensions allow easy integration into complex systems. Can LabVIEW run on a microcontroller? was answered positively and a solution was given. The most straightforward methods to achieve this target is to change the way code is generated from the LabVIEW diagrams and the way it is run on the microcontroller. The solution presented starts from the LabVIEW LabVIEW Real Time (LVRT) pair and reduces the size of LVRT maintaining as much as possible from the original functionality. The result was cod named Matchbox. By choosing the most powerful microcontroller available on the market at that time, target achievement was surely successful. Resulted prototype is an SBC based on the ARM7TDMI core, with prices around $100, processor running at 32 MHz, 136kB of RAM and 1MB of FLASH, wide enough for storing the main part of ecos operating system V1.02 and TCP/IP stack. Figure 2. Top view of EDAS card (a) and SPI interface enabled EDAS card (b) In case of direct connection with a computer (for avoiding collisions on the network) the system can achieve dedicated DAQ Card performances. Possible connections to the system are an RS232 serial interface and the 10Base-T Ethernet, while the system can be reprogrammed using JTAG interface. Power consumption is as low as 500mW. This value is around 10 times lower than the values recorded for other systems capable of acquisition, data processing and transfer through Ethernet network. Compared to a PC, the equivalent of this system would be a 20MHz 386 processor based PC. Future development of this microsystem has been done and presented in Chapter 3. The new version is based on the first version but has no DAQ part. Instead, it has two high speed serial peripheral interfaces (SPI) see Figure 2. b. This version allows users to connect their own, custom built, acquisition modules. A didactic heating microsystem was built to demonstrate the performances of the new interface and the LabVIEW programming concept. Later on this didactic microsystem was 7

10 PhD Thesis - Development of Embedded Systems for Integration with Graphical Programming multiplied and at this time it is used in the teaching process, on Automation Equipment application section, at Technical University of Cluj-Napoca, Automation Department. Chapter 4 presents the Ethernet HUB for data nodes management. One of the main advantages of this microsystem is the flexibility. It allows application loading through Ethernet and flash writing, running this application at next startup. This application was presented at NI-Week The data acquisition system obtained by connecting the Ethernet HUB with radio enabled dedicated modules has very high computational power in its category and allows remote monitoring, signal analysis and local control loop for real-life systems. It has higher performances than the EDAS presented in Chapter 3 due to higher computational power and analog/digital input/output configuration flexibility. The device is TCP/IP ready and hosts a Linux operating system. Figure 3 presents one possible application including the Ethernet HUB and several radio enabled acquisition modules. The user controls everything from LabVIEW running on the PC. Commands are transferred to the LVRT running Ethernet HUB, which dispatches commands to through radio to the modules. Figure 3. General structure of the radio acquisition system Nowadays, the ARM with Linux platforms running LabVIEW Real Time can be distributed as access points in the acquisition network. This is possible due to the recent development of the LabVIEW ARM code generator and to the new compilers available and the LVRT protocol. This microsystem allows data acquisition in hardly accessible sites, where cables cannot be placed and is battery powered - autonomous. The results obtained in this project allowed: - Understanding problems related to distributed radio architectures; - Extensive experience in the field of high performance, low cost and low power microcontrollers; - Building custom environment for testing radio protocols; - Understanding plug and play requirements for radio devices; - Determining minimum requirements for battery powered devices. Resulted system can achieve, as well as EDAS, similar performances with a standard acquisition card installed into the PC, but only if the acquisition module is integrated into the HUB through serial interface (not radio). The prototype is a single board computer (SBC) based on the ARM7TDMI core, with prices around $150, 74MHz processor, 16MB RAM and 4MB flash, wide enough for storing 8

11 Linux operating system and LVRT. Five acquisition modules were developed based on ADuC824 microcontroller, with radio communication interfaces (Figure 4). Connections to the system are possible through serial RS232 and 10Base-T interfaces. The systems can be programmed through JTAG interface. The Ethernet HUB interface is a microsystem with personal computer characteristics from the hardware point of view as well as from the software point of view: operating system, flash file system, applications. Figure 4. Top view of the HUB and radio enabled acquisition module; LabVIEW panel for detecting and configuring modules The 2W power consumption is much lower than any other system capable of acquiring, processing and transferring data through Ethernet and radio. Compared to a PC, this interface is the equivalent of a 100MHz Pentium I system. Chapter 5, Flexible data acquisition system presents several embedded systems: - PXA250 processor module with data acquisition; - tiniest microsystem running Matchbox: LabVIEW Stamp; - PXA250 processor module and DAQCF data acquisition; - modular microsystem running LabVIEW Embedded. One of the major advantages of these microsystems is the possibility of changing their functionality by simply writing another application into them, through cable or wireless connection (Ethernet b, Bluetooth and IR). The application is written into flash memory and loaded on next startup. These applications were shown at NI-Week Also, the modular microsystem was part of an evaluation program. These microsystems have high computational power in their category, which allows them to perform remote monitoring, processing and real-life systems' control with higher performances than the systems presented in Chapters 3 and 4. Due to modularization, they achieve higher computational power and a wider range and combination of analog, digital or communication inputs and outputs. As in the case of the previous systems, performances are similar to a data acquisition board, but they can act as autonomous entities. 9

12 PhD Thesis - Development of Embedded Systems for Integration with Graphical Programming Most of them are TCP/IP enabled and run ecos or Linux operating systems. Input/output operations are supported by LabVIEW Embedded. They allow data acquisition from hardly accessible areas, are autonomous due to battery power and they are relatively low cost devices. The PXA255 processor based microsystem is the equivalent of an SBC, has 400 MHz processor, 32 MB SDRAM and 8 MB of FLASH and together with the DAQCF data acquisition card is priced around $300. The microsystem runs LVRT on Linux operating system (Figure 5.). Figure 5. Access point/data node with PXA255 processor The AT91FR40192 processor based modular microsystem is the equivalent of an SBC with data acquisition card, is priced around $200, has 68MHz processor, 256kB SRAM and 2MB FLASH and runs LabVIEW applications in ecos environment. These performances are gathered in 470 components placed in 4 cubic centimeters (Figure 6.). Figure 6. The modular microsystem, overview, applications Possible connections to the microsystems are serial: RS232, IrDA, Bluetooth and Ethernet b wireless, while programming can be done through JTAG interface. 10

13 Compared to other functionally similar data acquisition systems the power consumption was strongly reduced, achieving a range of 50mW...1.2W. Also computational power has been increased. This system has even higher performances that the systems presented in Chapters 3 and 4, systems that were already more performant than the existing equivalents. New horizons open through this modular microsystem for creating an open standards community able to change ideas and achievements regarding custom extension cards and associated drivers. To demonstrate the performance of these microsystems seven applications have been developed; they were considered to be the most significant. Each of these applications emphasize certain characteristic of the platform: - Acceleration and vibration measurement with the modular microsystem; - MP3 file player with the modular microsystem; - MP3 file player with PDA and DAQCF acquisition card; - Bluetooth miniature car control with the modular microsystem; - Distributed acquisition from several modular microsystems: o main VI runs on a PC; o main VI runs on the PXA255 based system and display is done on the PC; - Signal generator based on the DAQCF acquisition card: o the VI that generates the waveform runs on PDA; o the VI that generates the waveform runs on the PXA255 based system; - Data acquisition with the PXA255 based system and DAQCF card. 4. RESUME Personal information a)date of birth: 1972 august 20; b)address: , Cluj-Napoca, Meteor street, no. 6, bl. OZ2, ap.21; c)married. Education 1995 Technical University of Cluj-Napoca, Faculty of Automation, M.Sc. in Control Engineering; Technical University of Cluj-Napoca, Faculty of Automation, Postgraduate in Modern Techniques in Automatic Control ; Since 1996 PhD student in Control Engineering. Professional experience until junior assistant, Technical University of Cluj-Napoca, Faculty of Automation and Computer Science, Automation Department; until assistant, Technical University of Cluj-Napoca, Faculty of Automation and Computer Science, Automation Department; Since lecturer Technical University of Cluj-Napoca, Faculty of Automation and Computer Science, Automation Department. Teaching experience Digital Circuits laboratories, 2-nd year, Automation; Digital Automation Equipments course, 2-nd year, IT College; Electric and Electronic Automation Equipments laboratories, 3-rd year, Automation; 11

14 PhD Thesis - Development of Embedded Systems for Integration with Graphical Programming Digital Automation Equipments laboratories 2-nd year, IT College. Research experience Design and development of embedded systems with microcontrollers and microprocessors; Data acquisition radio networks: Ethernet , Bluetooth, Zigbee ; Digital control of industrial processes; Since August 2000 co-worker in development of embedded systems and acquisition interfaces for National Instruments USA. Foreign languages -English. Publications 2 books and 21 scientific papers published in journals or national and international conferences. Brevets and inventions 2 patents applied in USA. 5. List of most significant work and patents Patents homologated in a foreign developed country Crt. Author, title brevet-award, country No. 1. United States Patent Application DEPLOYMENT AND EXECUTION OF A GRAPHICAL PROGRAM ON AN EMBEDDED DEVICE FROM A PDA, By: Marius Ghercioiu, Horea Hedeşiu, Silviu Folea, Graţian I. Crişan, Ciprian Ceteraş, Ioan Monoses 2. United States Patent Application MODULAR COMPACT SENSOR INTERFACE, By: Marius Ghercioiu, Horea Hedeşiu, Silviu Folea, Graţian I. Crişan, Ciprian Ceteraş, Ioan Monoses Papers regarding the subject of PhD thesis published in journals or conference proceedings, a. Unique or first author Title Authors Pg. No. S. Folea, I. Naşcu, C. Vlasin Crt. No. 1. Ethernet Data Acquisition System 2. LabVIEW on Small Target S. Folea, M. Ghercioiu, H. Hedeşiu, C. Graţian, C. Ceteraş, I. Monoses Presentation location 6 AQTR THETA 14, 2004 IEEE-TTTC International Conference on Automation, Quality and Testing, Robotics May 13 15, 2004, Cluj- Napoca, Romania, Tome II, pag AQTR THETA 14, 2004 IEEE-TTTC International Conference on Automation, Quality and Testing, Robotics May 13 15, 2004, Cluj- Napoca, Romania, Tome II, pag

15 Crt. No. Title Authors Pg. No. Presentation location 3. Low Cost Data Acquisition S. Folea, I. Naşcu, C. Vlasin 6 A&QT-R 2002 (THETA 13) 2002 IEEE-TTTC International Conference on Automation, Quality and Testing, Robotics May 23 25, 2002, Cluj- Napoca, Romania 4. Paperless Recording System 5. Microcontroller-based digital recorder Crt. No. 6. Mobile Monitoring Technologies Applied to Electromechanical Systems S. Folea, I. Naşcu 6 International Conference on Quality, Automation and Robotics, Cluj-Napoca, May 2000, Proceedings, Tome I, pag. 257 S. Folea, I. Naşcu, C. Ceteraş b. Co-author Title Authors Pg. No. Hedeşiu, H.C. Folea, S. Chindriş, G. 7. Modular Embedded System M. Ghercioiu, S. Folea, H. Hedeşiu, C. Ceteraş, C. Graţian, I. Monoses 8. PID Auto-tuning algorithm for processes without time delay 9. Digital Recorder Using Serial Printer I. Naşcu, R. De Keyser, S. Folea, C. Vlasin I. Naşcu, S. Folea, C. Ceteraş 10. Adaptive generalized predictive I. Naşcu, T. Coloşi, control. The basic algorithm and S. Folea a simulation study 11. Distributed control system based on low-cost infrastructure and open source software. 12. Practical aspects in the implementation of adaptive controllers. Pole placement and predictive approach. 13. Adaptive generalized predictive control. I. Naşcu, S. Folea, C. Ceteraş I. Naşcu, P. Raica, S. Folea I. Naşcu, T. Coloşi, S. Folea 14. Ultrasonic range finding sensor Ghe. Lazea, E. Lupu, S. Folea 15. Adaptive control of a steam superheater 4 EMES 99, Engineering of modern electric systems, Oradea, May 1999, Analele Universităţii din Oradea, Fascicola Electrotehnică, pag. 46 Presentation location 4 Proceedings of the 12th National Conference of Electrical Drives CNAE '2004, Cluj- Napoca, Romania, published in Acta Electrotehnica, vol. 44, no. 3, 2004, pp AQTR THETA 14, 2004 IEEE-TTTC International Conference on Automation, Quality and Testing, Robotics May 13 15, 2004, Cluj-Napoca, Romania, Tome II, pag AQTR THETA 14, 2004 IEEE-TTTC International Conference on Automation, Quality and Testing, Robotics May 13 15, 2004, Cluj-Napoca, Romania, Tome I, pag International Conference on Quality, Automation and Robotics, Cluj-Napoca, May 2000, Proceedings, Tome I, pag th International Conference on Optimization of Electrical and Electronic Equipment, Brasov, May 2000, Proceedings, pag ICCoS Identification and Control of Complex Systems Workshop, Ghent University, May ICCoS Identification and Control of Complex Systems Workshop, Ghent University, May EMES 99, Engineering of modern electric systems, Oradea, May 1999, Analele Universităţii din Oradea, Fascicola Electrotehnică, pag International Conference on Automation and Quality Control A&Q 98, Cluj-Napoca, May 1998, Vol.A, pag. A337 I. Naşcu, S. Folea 6 International Conference on Automation and Quality Control A&Q 98. Cluj-Napoca, May 1998, Vol.A, pag.a87. 13