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1. e 132 pin quad flat pack 0 8 um CMOS It can work as a microprocessor or as a microcomputer boot loader easily selective by the state of MCB MP pin These two modes use different kind of memory maps Special memory locations are used by the loader 4 1 TI TMS320 Family The Texas Instruments TMS320 family of digital signal processors is designed to support a wide range of high speed and numeric intensive DSP applications These 16 32 bit DSP s combine the flexibility of high speed controller with the numerical capability of an array processor The TMS320 family contains microprocessor capable of executing very high throughput as a result of comprehensive efficient and easily programmed instruction set and highly pipelined architecture 21 22 TS320C31 Analog to Xd Digital DSP Converter Digital to Ch 0 Memory Analog 128k words Converter Ch 1 Figure 4 1 TMS320C31 Architecture 4 2 The Delanco Spry Board The DSP system used for this project was the Dalanco Spry Data Acquisition and Signal Processing Board Model 310B The DSP board has a Texas Instruments TMS320C31 DSP chip running at 50MHz a 12 bit DAC a 14bit ADC with a four channel multiplexer and 128k words of memory The memory on the DSP board is dual ported i e it is accessible at any time to the DSP as well as to the PC via the bus interface The ADC and the DAC are however accessible only to the DSP Any data from the ADC and to the DAC must pass thr
2. However when the size of sequence is power of 2 Neo Formes 172 9 s Implementation of DFT becomes quite faster and is referred to as Fast Fourier Transform LabVIEW gives us two types of FFTs Real FFT and Complex FFT 3 6 Using LabVIEW for Our System We discussed the development of the LabVIEW front Panel of Hysteresis testing program in chapter 2 let us continue with the same example LabVIEW s Front Panel Design Toolbox gave us the different Controls and Indicators these could have been connected to the icon thus providing capability of our Hysteresis test VI to serve as a subVI to other VIs However we chose not to do so our icon just depicts graphically a hysteresis plot The Block diagram of the hysteresis VI is shown in Figure 3 2 and 3 3 Basically we have made a case structure which decides which block diagram will lt a FEON Figure 3 2 The Block diagram of the case true Hysteresis be executed on the bases of the true false condition of the control connected to it Execute Download button In case of false condition we execute a batch file which downloads our desired DSP program into the DSP memory In the case of true control signal the other block diagram is executed The case true block diagram mainly runs the CIN VI which executes the code for Hysteresis test available in Appendix B and discussed later The sampling rate and desired operation voltage are handed over to the CIN to be transferred to DSP and the
3. istas EHP suu LabVIEW GQ Tera Te i 5505 af FS Hysterice fn Snagit 32 lr Hysteri 9 1252PM Figure A 3 The Block diagram of the case true Hysteresis gt Hysterises vi Diagram Fie Edt Operate Project Windows Help F9 SL Peal 3s Tet Application Font 5 2 21 69 1 ee ta n lis stert EHP stans Laview lreeTem ls oos Pi Ef Hysterises vi E Hysterise tn Seg FETI Figure A 4 The Block diagram of the case false Hysteresis P Iv _tan vi Diagram Fie Edt Operate Project Windows Hep 00 0 0 0 00 0 0 00 0 00 Pa T3ptAppication Font 2 2 tee C Astun EEJHP Status Bc LabVIEW gres Term i 5005 Pif Breni tij Snagit 32 E rni 1 03PM Figure A 5 The Block diagram of the case true range of displacement gt lv ran vi Diagram Fie Edt Operate Project Windows Heip TaptAppicaton Font S zl fi Command com c range bat Exec ca W Stort EHP stats Labview Gy tera Tem Ms oos Pi Bn ES roni Sng s SET Figure A 6 The Block diagram of the case false range of displacement gt Iv_it_vi Diagram Eje Edt Qperate Project Windows Heb ere ELA Stat EHP Status Bre Tem i Sos Pr Lamiew tvi srv foro 1 17PM Figure A 7 The Block diagram of the case true Resonance Frequency gt Iv if vi Diagram Eie Edt Qperate Project Windows Help Aa Ian AppicatonFo Jesi SS ta False PI
4. Au nT u nT u nT T u nT u n 1 T we use this to get q aa Au n 1 T T audnT S q y nT This is called the incremental form of the controller A drawback of incremental controller is that it cannot be used for P or PD controllers 6 5 1 The Front Panel The front panel of the PI control VI is displayed in Figure 6 5 and consists of following e Control input for sampling rate e Control input for reference setpoint e Control input for the Proportional gain KP e Control input for the integral gain KI e Binary control button for the download execution selection gt lv piv d E f H ad i zT f j JT Figure 6 5 The Front Panel of the Proportional Integral program e Control input for bias e Display for the value of y n e Display for the value of u n e Graph of the data received by the DSP y n We can give integer values to the control input for the sampling rate this value is written to the CIN The control for inputs for KI KP bias and reference accept floating point values for the data to be sent to the DSP the value has the precision of two decimal places the display is also configured to display only two decimal places The binary button select whether we want to download the DSP program to interface with the DSP block VI into the DSP or we want to execute the program in the DSP The data which is most current is displayed as the y n and u n on the screen
5. The objective of this thesis is to present the application of LabVIEW as a graphical User interface GUI for the Digital Signal Processor The LabVIEW version 5 was aged to carry out G language implementation of user interface Code Interface Nodes CIN s were used to exchange necessary data with the DSP The DSP programming was carried out in C language 1 2 TI TMS320C31 DSP The TI TM S320 family of Digital signal Processors combines the flexibility of high speed controller with the numerical capability of an array processor Thus an impressive and economical alternative to VLSI and multichip bit slice processors for signal processing TM5320 family offers both Fixed point and Floating point DSP generations The Calanco SPRY mode 3 2 data acquisition and signa processing board was used as the housing of the DSP This board provides us with two D A converters and four A D converters The relationship is expressed in Fig 1 1 1 3 LabVIEW LabVIEW is a program development environment it is different from other program development environments for it uses graphical programming language rather than text base language LabVIEW is a general purpose programming system with extensive libraries of functions for any programming task LabVIEW includes libraries for data acquisition GPIB and serial instrument control data analysis data presentation and data storage LabVIEW Figure 1 1 The Block diagram representation of our system
6. int32 numDims MgErr err bogusError array 75 Start the DSP program execution mEIEEE I mmrImiImrrzmmmrmmmrummzcmzmII nz0 Put the DSP to go inp 0x306 Actual Data Acquisition is carried out t ttt EEE EEEE EEEN numDims 1 This is a one dimensional n 2047 The length or no of elements of array if err NumericArrayResize fD numDims UHandle amp DSP Input n goto out Input array is adjusted if err NumericArrayResize fD numDims UHandle amp DSP_Output n page value address 8 2 goto out Output Array is adjusted DSP Input dimSize n Input array DSP_Output gt dimSize n Output array check 0 while check 1 The logic to set the sampling rate outp 0x306 PAGE VALUE set the outpw 0x302 Timer_Address Sets outpw 0x300 50000000 Sanpling Rate sets the sampling rate outp 0x306 PAGE VALUE 76 outpw 0x302 Voltage_Address outpw 0x300 voltage outp 0x306 PAGE VALUE outpw 0x302 Check Address Check address is set check inpw 0x300 wait for the DSP to finish its work endwhile for i20 1 2047 i 1 Signal sent by the DSP is stored in Array DSP Input outp 0x306 PAGE VALUE outpw 0x302 ADDRESSI i ui6_bit inpw 0x300 Sign u1l6_bit amp 0x0800 ui2_bit ui _bit amp Ox07ff if sign 0 DSP_Input gt argili float64 u12 bit 409 0 e
7. Acquisition is carried out e REPERI aE s2222222z22zz2zz2zz2mB5e s 2 numDims 1 n24095 if err NumericArrayResize fD numDims UHandle amp DSP Input n goto out DSP_Input gt dimSize n check 0 while check 1 The logic to set the sampling rate SSsereSsesssasseesaesseaeeaSessses e outp 0x306 PAGE VALUE outpw 0x302 Timer Address outpw 0x300 50000000 Sampling_Rate outp 0x306 PAGE_VALUE outpw 0x302 Check_Address check inpw 0x300 endwhile for i 0 i lt n i Signal sent by the DSP outp 0x306 PAGE VALUE outpw 0x302 ADDRESSI i ui6_bit inpw 0x300 sign ui6_bit amp 0x0800 u12 bitzui6 bit amp Ox07ff if sign 0 i 84 DSP_Input gt argi i float64 u12 bit 409 0 endif else ul6_bit ul6_bit u16 bitzui16 bit 1 u12 bitzui16 bit amp OxOfff DSP Input argi i float64 ui2 bit 409 0 if DSP Input argi i lt 5 0 DSP Input argi i s 5 0 endelse endfor Check is reset to 0 outp 0x306 PAGE VALUE outpw 0x302 Check Address outpw 0x300 0 Halt the DSP program execution inp 0x307 return noErr out return err end CIN 85 B 5 The PI Control CIN CIN source file for PI control The DSP is set to go then the Sampling time reference KI KP and Bias are wriiten to the DSP the DSP then writes out this value
8. DSP address 0x01387 The check flag is checked repeatedly until it is set by the DSP marking the complete execution of the experiment It is important to note that CIN allows non LabVIEW programs to run in the Windows 95 environment Once the DSP confirms that the necessary data has been acquired the CIN reads the data input to the DSP from the address 0x01388 onwards and the DSP output from address 0x02788 onwards After necessary data scaling and manipu lations the data is stored in the structures to be passed on to LabVIEW The check flag is rest to 0 and the DSP is halted to stop further execution of the program as CIN ends its execution 44 It is important to note that the execution of this VI depends very heavily on the sampling rate selected and care needs to be exercised to select a sampling rate which will not allow the dynamics of the system to be wrongly interpreted 6 2 4 The DSP Program The DSP program of the hysteresis experiment adjusts the sampling rate of the system to the desired rate passed by the CIN then it calculates the output signal it needs to send out at that particular instant which depends on the position of the position counter i It is important to note that the program generates a triangular waveform which goes from 0 to maximum then back through zero to minimum and then again through 0 to maximum desired voltage level The sampling rate has to be slow enough to simulate DC voltage levels for the system rat
9. Diagram secarei nea gi vases I eem d ee 54 D 5 3 The TN ao once e Ex Ga ae My eRe ea ae A 8 54 6 04 The DSP Program Sume ba ree Lane ge See ee eee eas 55 CONCLUSION z 4 uei w bebe Rak hosts eke wee heres E 56 fl DINCTING c o piston eh ot BEE Aare een OR hea ae Ra dices 58 1 2 PI Completely Programmed in LabVIEW 005 60 7 3 Drawing a Circle with PZT 2 0 ee ee ee 62 APPENDIX A THE BLOCK DIAGRAMS 64 APPENDIX D CHE COINS sx deter ered ee ah aus he es anaes 71 APPENDIX C THE DSP PROGRAMS ix LIST OF FIGURES Figure Page 1 1 The Block diagram representation of our system 0 6 2 2 1 The Block diagram of data flow llle 6 3 1 Block Diagram depicting LabVIEW VI structure 10 3 2 The Block diagram of the case true Hysteresis 04 14 3 3 The Block diagram of the case false Hysteresis lies 15 3 4 The Block diagram of the input output llle 19 41 TM5320C3 Architecl re aues eR ER e ORARE E Ep a 22 AD Synchronization to T OLI a scd canes m doc CELA CK DEP CR RU 28 4 3 Successive Read and Write Events 0 000 pee eee eee 29 5 1 The Block diagram of our plant co bead bee ee ee Rey a 34 6 1 The Front Panel of the DSP Block 0 38 6 2 The Front Panel of the Hysteresis program 5 41 06 3 The Front Panel of the PZT Range zm REC n Peas 45 6 4 The Front Panel of
10. LabVIEW programs are called virtual instruments VIs These VIs are similar to the conventional programing language programs A VI consists of three inter linked items the interactive user interface Front Panel a dataflow diagram Block Diagram that basically is the G language source code and an icon to connect the program to other high level VI programs The icon works like a graphics parameter list to provide connection and data exchange between VI programs LabVIEW adheres to and promotes the modular programming concept Thus we can develop an hierarchy of VIs and subVIs which each perform a task leading to the end result This makes debugging easier as we can execute each subVI by itself These subVIs can also be used as a library and recalled and included in other VIs which need similar functions 3 G is easy to use graphical data flow programming language on which LabVIEW is based Scientific calculations process monitoring and control test and measurement and a wide variety of applications can be developed in G 1 4 Organization of Thesis Chapter 2 of this thesis discusses the Graphical User Interface programing and concepts involved in such a task Chapter 3 discusses the LabVIEW development environment and the functions used for our purposes It explains mainly the different VIs in LabVIEW which were used in our development of the GUI for DSP and also some relevant discussion on the CIN programming environment Chapter
11. and respect for Dr Timothy N Chang who not only served as my research supervisor providing valuable and countless resources insight and intuition but also constantly gave me support encouragement and reassurance Special thanks to Dr Marshal Kuo and Dr Dao Chuan douglas Hung for actively participating in my committee Special thanks to Xuemei Sun Vincent Pappano Robin Nikfar Hamid Ghods Bhaskar Dani and many graduate students in the NJIT Electrical and Computer Engineering department Finally I would like to thank the NIST ATP Grant number 70NANB5H1092 for Precision Optoelectronics Assemply for extending financial support for this thesis and also the NJIT for their financial support vi TABLE OF CONTENTS Chapter Page I INTRODUC HON moanne ein ant Wh SMe oe Redd e Se es WW Ae A 1 D ODECE soe ake ae eee ee anes oe ee ae eG dag ae 1 gt M TMSU DOR 9 24 Shane coe he oe nares Eae ES RES 1 TS Ha UID TP IRE 1 iA Organization of Thesis 64 blur RUE VR ERU ES 3 2 GRAPHICAL USER INTERFACE 0 0 cece ee eee 4 2 1 Life Cycle of Software Development 0 0 0 0000s 4 2 2 GUI Development s cce Spade ROC Secs Aca S ar CS BOS 4 2 3 GUI Implementatie esen ia decree wes ee os Seep i ek aa EG 5 2d Our GM Stra e Hun ete x pin kk de dow ada haa ee or hee ew 6 2 4 1 An Example of Our GUI ois cst hn ELO 4 RA 7 B LABVIEW gs ce tp Ged aac Beda at qa rit OR ctc dd un e ge ai did 9 9 WG Programmes cca ee eet potu
12. arrays of data to the LabVIEW which are stored in DSP input and DSP output arrays These arrays are then combined together to form a cluster of two dimensional data which is then passed on to the XY graph another two dimensional array is formed which is then passed on to subVI write to spreadsheet This subVI asks the user the name of the spreadsheet format data storage field This operation can be cancelled or completed by the user by a file saving dialog box 43 Incase of the case false input from the download execute button the block diagram shown in the Figure A 4 in appendix A is executed This calls the batch file hyst bat which compiles and downloads the DSP program to interface with the LabVIEW Hysteresis VI 6 2 3 The CIN The CIN creates two handles for the arrays of data which will be transferred between the CIN and LabVIEW It accepts two pointers one for sampling rate and another for the desired maximum voltage level An important thing to note is the Numeri cArrayResize function and its not so user friendly interface Caution needs to be exercised with this function since it causes LabVIEW to crash if not properly handled This function configures the data structure which will transfer data back to LabVIEW The DSP is put into execution mode to perform the experiment The CIN calculates the hexadecimal value to be transferred to the DSP in order to get the desired sampling rate as writes the result of these calculations to the
13. as well as the u n is plotted so as to facilitate in the tuning of the PI controller 54 This VI can be run only be put into repetitive runs from the control toolbar on LabVIEW Care should be taken in using the VI as a subVI since we will need to DL the DSP program into the DSP This VI is written so as to support and provide capabilities for the user to develop his own experiments which use the DSP to read and write one channel each and perform a PI control 6 5 2 The Block Diagram The block diagram shows that the Sampling rate is written as it is to the CIN The CIN has six Input Output terminals accepting the Reference KI KP Bias and the iteration number i All data except the sampling rate and the iteration number are scaled by a factor of 100 to give two decimal places accuracy It has two outputs one for y n other for u n The data sent by the DSP is available at the output only terminal and is already properly scaled to give the voltage read by the DSP y n data is only displayed in the digital format to give a form of feedback as to the output DSP is giving and the u n is not only displayed but also plotted to display the actual performance of the PI controller The Block diagram is shown in Figure A 10 Incase of the case false input from the download execute button the block diagram shown in the Figure A 11 in appendix A is executed This calls the batch file pi bat which compiles and downloads the DSP program to interface wit
14. be sent to the DSP on address 0x1388 After doing that the CIN waits for the DSP to actually send this data out to the D A and read data from the A D When the check flag is set the CIN reads the data value from the DSP address 0x01389 and ends its execution after resetting the check flag 40 6 1 4 The DSP Program The DSP program to interface with the DSP block VI is available in Appendix C The DSP program first checks if it is running the DSP at the desired sampling rate then it manipulates and write the data at the address 0x01388 to the D A Then reads and stores the data from A D to the address 0x01389 and sets the check flag 6 2 Hysteresis with Dither Hysteresis is defined by Webster s Seventh new collegiate Dictionary as A retardation of the effect when the forces acting upon a body are changed as if for viscosity or internal friction esp a lagging in the values of resulting magnetization in a magnetic material as iron due to a changing magnetizing force hys ter et ic adj Hysteresis represent the history dependence of physical systems If something is moved and when released springs back to its original position if it does not relocate itself exactly on its original position it is exhibiting hysteresis The term most commonly associated with the magnetic materials However hysteresis occurs in a lot of other systems like bending of fork if pressed to hard etc Hysteresis loops happen when we repeatedly wiggle the s
15. can be run only once or can be put into repetitive runs from the control toolbar on LabVIEW Care should be taken in using the VI as a subVI since we will 39 need to DL the DSP program into the DSP This Vl is written so as to support and provide capabilities for the user to develop his own experiments which use the DSP to read and write one channel each 6 1 2 The Block Diagram The block diagram shows that the Sampling rate is written as it is to the CIN the Data to be sent to the DSP is however scaled as the DSP uses value 409 for outputing 1 volt through the D A This called value is provided to the CIN The CIN can be seen to have two I O terminals and one output only terminal The data sent by the DSP is available at the output only terminal and is already properly scaled to give the voltage read by the DSP This whole logic is enclosed in a case true box and the case value is decided by the download execute button Please refer to Appendix A for the Figure A 1 which shows the case true block diagram Incase of the case false input from the download execute button the block diagram shown in the Figure A 2 in appendix A is executed This calls the batch file dsp bat which compiles and downloads the DSP program to interface with the LabVIEW DSP block VI 6 1 3 The CIN The CIN source code is available in the Appendix B The CIN takes the sampling rate and writes it down to the DSP memory address 0x01387 Then it writes down the data to
16. numDims defines dimensions of array Function NumericArrayResize is used to resize the data handle This function also accounts for alignment issues It does not set the array dimension field The usage is 17 Table 3 1 Constants for the typecode argument in NumericArrayResize function Constant Function B Data is an y ofaguel 80H integers iW Data is an array of signed 16 bit integers JL Data is an array of signed 22 bit integers B Data is an array of unsigned Pii integers aW Data is an array of uneigned 16bit integers ul Date is an array of unsigned 31 bit integers Data is an array of single precision 32 bit numbers D Data is an array of double precision 32 bit numbers fX Data is an array of extended precision 32 bit numbers cS Pata is ar array of sirg e precisior corr plex rumbers D Data is an array of double precision complex numbers eX Data is an array of extended precision complex numbers MgErr NumericArrayResize int32 typecode int32 numDims Uhandle dataHP int32 totalNewSize The variable typecode describes the data type for the array that we want to resize The header file extcode h has defined constants for this argument shown in Table 3 1 The variable numDims describes the number of dimensions in the data structure to which the handle refers Thus if the handle
17. simple hysteresis curve by more than 70 by using LabVIEW to directly supervise the DSP operation during the process of data acquisition set the experiment setpoints collect the data from DSP and then carrying out the necessary analysis and displaying and storing the data if desired This also improved the end result in the form of our X Y graph as we were able to get better resolution and overall a smoother graphical representation of our results Similar time savings were achieved for all experiments The normal course of carrying out an experiment was to use two or more software platforms to individually perform each and every task of experiment at different stages Now all the user has to do is press a button The most important issue was of performance LabVIEW software provides us with an excellent tool called the performance profiler It gives an interactive tabular display of time and memory usage of our application Our main concern was time and the rate of data exchange Table 7 1 Profiles of VI programs Longest 26 441 11 248 27 689 Range of Displacement 26 496 27 183 8 832 85474 87 713 9497 27 718 38009 13 859 56 57 Front Panel Plant Figure 7 1 The Block diagram of data flow The Table 7 shows profile of test results of running the VI s for 10 times Important thing to remember is that the Range of displacement and the PI are real time VI s and therefore their exac
18. 16 bitzul16 bit 1 73 u12 bitzui6 bit amp OxOfff Stores 2 s complement value Data sent by DSPz float64 u12 bit 409 0 if Data sent by DSP lt 5 0 Data sent by DSP 5 0 endelse The Logic to reset the check ZEIXZALXEXIXXZZZAAXLZZLZILZLXXZAZ outp 0x306 PAGE VALUE set the page value outpw 0x302 Check Address Check address is set outpw 0x300 0 return noErr B 2 The Hysteresis CIN CIN source file for the hysteresis measurement The DSP is set to go then the Sampling time and the desired voltage range are selected and PC waits for the DSP to finish and then loads all data into the LabView arrays Hinclude extcode h Hinclude lt stdio h gt include lt math h gt Hinclude lt conio h gt typedefs typedef struct int32 dimSize float64 argi i TD1 typedef TD1 TD1Hdl CIN MgErr CINRun int32 Sampling Rate TDiHdl DSP Input TDiHdl DSP Output int32 voltage CIN MgErr CINRun int32 Sampling Rate TD1Hdl DSP Input TDi1Hdl DSP Qutput int32 voltage ENTER YOUR CODE HERE All variables used in this function are declared ZTIIZZXEZLZIAZZLZINLZIIXZLZIZLZIZZILZLIZLZAZZINXZIIEZEIXXZEIZZLZLZLZIZLI int sign ui6 bit ui12 bit y16_bit y12_bit i n Data handling with signed numbers int PAGE_VALUE 0x0 ADDRESSI 0x1388 ADDRESSO 0x2788 Timer_Address 0x01387 int check Check_Address 0x1386 Voltage Address 0x1385
19. 4 discusses the TI TMS320 family of the DSPs and the Delanco SPRY rode 310 board we kave used to perform our tasks Chapter 5 discusses the plant used for our work We used PZTs as our test subject for the application Experiments to carry out studying of the PZT behaviour were implemented using the LabVIEW and DSP working in tandem Four exper iments were mainly implemented to study the hysteresis characteristics of the PZT To find out the range of displacement of the PZT leading to a measure of the scale of PZT displacement to applied voltage The plant used for our testing is also included in this chapter Chapter 6 discusses the actual implementation of the experiments It covers discussions on considerations for the front panel design the Block diagram programming the Code Interface Node programing and the DSP programs Finally in chapter 7 the conclusion of this work along with future directions for research are provided CHAPTER 2 GRAPHICAL USER INTERFACE 2 1 Life Cycle of Software Development The software development life cycle approach has evolved over the years to a structured approach from a waterfall model The structured development may include survey analysis design implementation acceptance test quality assurance user documentation final installation and interactions between these activities Survey includes feasibility study and the study of the possible approaches towards solving the issue The System analysi
20. 8 National Instruments G programming Reference Manual Jan 1998 National Instruments LabVIEW Function and VI Reference Manual Jan 1998 R M Evan Iwanowski In R Cooper editor Resonance Oscillations in Mechanical Systems Elsevier Scientific publishing company New York 1976 98
21. Besrseserssenssssssssss outp 0x306 PAGE_VALUE outpw 0x302 bias_address outpw 0x300 Bias outp 0x306 PAGE VALUE outpw 0x302 Check Address check inpw 0x300 endwhile The Logic to read the Signal going from DSP a outp 0x306 PAGE VALUE outpw 0x302 ADDRESSI 80 ui6_bit inpw 0x300 sign ui6 bit amp 0x0800 u12 bitzui6 bit amp Ox0T7ff if sign 0 Incoming_Signal float64 uL2_bit 409 0 endif else ul6_bit ul6_bit ui16 bitzul16 bit 1 ui2 bitzui16 bit amp OxOfff Incoming Signal float64 u12 bit 409 0 if Incoming Signal lt 5 0 Incoming Signals 5 0 endelse The Logic to read the Signal coming to DSP sS SSS SSS SS SS SSS SS SSS SSS SS SS SS SS SSSI SS TTT outp 0x306 PAGE_VALUE outpw 0x302 ADDRESSD y16_bit inpw 0x300 signzy16 bit amp 0x0800 yi2_bit yi6_bit amp Ox07ff if sign 0 Qutgoing Signals float64 yi2_bit 409 0 endif else yi6_bit y16_bit yi6 bitzy16 bit i y12 bitzyi6 bit amp OxOfff Qutgoing Signal float64 y12_bit 409 0 if Outgoing Signal lt 5 0 81 Qutgoing Signal 5 0 endelse The Logic to read the range of movement ee ee ae ee ee oe ee ee we we we we ee oe SS SS SSS SSS SS SSS SSS SS SS SS ST SS SS SS SS SS SS outp 0x306 PAGE VALUE outpw 0x302 Range Address y16 bitzinpw 0x300 Sign y16_bit amp 0x0800 yi2_bit yi6
22. Copyright Warning amp Restrictions The copyright law of the United States Title 17 United States Code governs the making of photocopies or other reproductions of copyrighted material Under certain conditions specified in the law libraries and archives are authorized to furnish a photocopy or other reproduction One of these specified conditions is that the photocopy or reproduction is not to be used for any purpose other than private study scholarship or research If a user makes a request for or later uses a photocopy or reproduction for purposes in excess of fair use that user may be liable for copyright infringement This institution reserves the right to refuse to accept a copying order if in its judgment fulfillment of the order would involve violation of copyright law Please Note The author retains the copyright while the New Jersey Institute of Technology reserves the right to distribute this thesis or dissertation Printing note If you do not wish to print this page then select Pages from first page to last page on the print dialog screen New Jersey s Science amp Technology University The Van Houten library has removed some of the personal information and all signatures from the approval page and biographical sketches of theses and dissertations in order to protect the identity of NJIT graduates and faculty ABSTRACT GRAPHICAL USER INTERFACE FOR THE DSP USING TEXAS INSTRUME
23. Dap Rage de Segue d dod 9 3 2 Code Interface Nodes iua er id e ot f een Roo fta 10 dia Graphis ae web wi Te AAA UE bed ose abd ane buo Pol o uod 12 Dido EXC Fonton cow dresses aid ws Ward a hr dU RR ad ar pb er 12 go Past Fournier Translorrios 3 acee tele SR RC DDR CRAS OR 12 3 6 Using LabVIEW for Our System eee eee 13 3 6 1 The CIN for Our Example seen 16 4 TEXAS INSTRUMENTS TMS320C31 DSP 21 CL OTITMSS2U Family vozesubeobe sm v uiu ace En PE relied aae 21 4 2 The Delanco Spry Board llle ee ee 22 4 3 The TMS320C31 Digital Signal Processor 0004 23 4 mitia atoi cue RR REL ENS bx pua ats 24 vii Chapter Page Hoy AAC sage cou eae eee Ge cade go ee eo on 26 AO NDC Uae uu se E ox NS ie CES Se oh ee Flee Seaweed 27 4 7 Sampling Rate Determination 002 eee eee eee 28 4 8 Runtime Sampling Rate Determination ceres 29 4 9 Data Exchange between the PC and the DSP Card 30 5 PRE PUANTCPLL boit dos Drei Ced ro eld oet reo deed 31 5 1 PZT Ceramics Manufacturing Process 0 0002 eee 31 5 2 Advantages of Piezoelectric Positioning Systems 32 5 3 Displacement of Piezo Actuators llle 33 5 4 Considerations for PZT Usage 0 6 0 cc eee ee wee eee ew ans 33 5 4 1 Mechanical Considerations 0 2000 ee eee 33 5 4 2 Electrical Considerations 0 00 00 eee eee eee 34 5 4 3 T
24. EDIRE manie outp 0x306 PAGE VALUE outpw 0x302 Check Address outpw 0x300 0 return noErr endmain APPENDIX C THE DSP PROGRAMS C 1 DSP Program for the DSP Block Program define TIMPERO 0x186A include D3i10BI0 H void main int input_pointer output_pointer check output int timer_pointer desired_rate timer_pointer int 0x1387 timer_pointer TIMPERO desired_rate timer_pointer input_pointer int 0x1388 output_pointer int 0x1389 check int 0x1386 InitDsp while 1 if timer pointer desired rate int p7 p7 int CTRL p7 0x28 timer_pointer p7 0x20 TIMGBOSTART desired rate timer pointer if output_pointer gt 2047 1 output pointer 65535 output pointer 1 output pointer output pointer 1 if output_pointer lt 2047 output pointer output pointer amp 0x0000ffff input_pointer ReadAdc 0 output output_pointer WriteDAC output 0 check 1 end while end main 89 90 C 2 The Hysteresis Program define TIMPERO 0x7a12 include D310BI0 H void main 1 int input pointer output pointer int timer pointer desired rate int i check voltage output timer pointerz int 0x1387 check int 0x1386 voltage int 0x1385 timer_pointer TIMPERO desired_rate timer_pointer input_pointer int 0x1388 output_pointer int 0x2788 InitDsp WriteDAC 0 0 WriteDAC 0 1 check 0 v
25. LEEAELAXEAXAXLEEAELITZ int sign u16 bit ui12 bit Data handling with signed numbers int PAGE_VALUE 0x0 ADDRESSI 0x1388 ADDRESSO 0x1389 Timer _Address 0x01387 int check Check_Address 0x1386 Start the DSP program execution SSS SS S255 5555255555555 5 55 inp 0x306 while check 1 71 72 The logic to set the sampling rate SS SSS SS SSS SSS SSS SSS SV SSS STS SSS TTT outp 0x306 PAGE VALUE set the page value outpw 0x302 Timer Address Sets address 0x1387 outpw 0x300 50000000 Sampling Rate 8 2 The logic to send the Output z22zzzzzzzzzzzzzzzzzzzzzmzmz outp 0x306 PAGE VALUE set the page value outpw 0x302 ADDRESSO Sets address 0x1389 outpw 0x300 var2 sets the bias for sine wave The logic to check if DSP is ready CE outp 0x306 PAGE_VALUE set the page value outpw 0x302 Check Address Check address is set check inpw 0x300 wait for the DSP to finish its work endwhile The Logic to read the Signal from DSP tt tS outp 0x306 PAGE VALUE set the page value outpw 0x302 ADDRESSI Sets address ADDRESSI 0x1388 ui6 bit inpw 0x300 read 16 bits sign ui6 bit amp 0x0800 ul2_bit ul6_bit amp Ox07ff if sign 0 Data_sent_by_DSP float64 ui2_bit 409 0 if Data sent by DSP gt 5 0 Data sent by DSPs 5 0 endif else ui6 bitz ui6 bit desired negative output voltage 0 5 ui
26. NTS TMS320C31 AND LABVIEW by Tahir Nazir Digital Signal Processors DSP s have become very popular due to their ease of operation economic value adaptability and availability However the devel opment environments for the DSP are still the archaic Assembly and C language programming It is tedious error prone and time consuming to develop and use DSP applications using these compared to Graphical User Interface development tools if available In the modern age programming is very heavily done in object oriented graphical languages like the Visual C and Visual Basic Windows also gives a good graphical user interface LABVIEW with its readily availab e ensemble of good analysis programming and development libraries and engineering tools was a good candidate G programming also gives ease of operation and relative economy in programming time along with good capabilities for hardware interfacing We have used Code Interface Node programmed in C language act as a bridge between the LabVIEW and DSP and then carrying out the analysis in the LabVIEW and using the DSP for collecting of data The complete DSP control and monitoring is carried out by the LabVIEW along with acquisition of data collected by the DSP The real world interface and analog to digital conversion is carried out by the DSP and LabVIEW is used to analyze and present the data in a more user friendly and graphical manner The Use of LabVIEW has significantly reduced the time re
27. P 0 01 KI dbls KI 0 01 yn yn 1 KP_dbl KI dbl Ts en KP_dbl en 1 if yn gt 4 997 ynz4 997 if yn lt 4 997 ynz 4 997 4 9976 yn bias 409 0 endwhile endmain 97 output pointers int 2047 0 if output pointer gt 2047 output pointer 2046 if output pointer lt 2047 output pointer 2040 WriteDAC output pointer en izen yn_i yn check 1 10 Lb 12 13 REFERENCES Texas instruments TMS320C31 Addendum to the TMS320C8x User s Guide 1990 Texas instruments TMS320C8x User s Guide 1990 Texas instruments TMS320 Floating point DSP optimizing C Compiler 1995 Dalanco Spry 89 Westland Ave Rochester NY TM5320 Floating point DSP optimizing C Compiler 1995 Geoff Lee Object Oriented GUI Application Development Prentice Hall Englewood Cliffs NJ 1993 Mark A Krasnoselski Aleksei V Pokrovski Systems with Hysteresis Springer Verlag NY 1989 Karl J Astrom Bjorn Wittenmark Computer Controlled Systems Theory And Design Prentice Hall Upper Saddle River NJ 1997 Tian Hong Control of Smart Structure using adaptive dither Masters Thesis Department of Electrical and Computer Engineering New Jersey Institute of Technology Newark NJ 1994 http www lassp cornell edu sethna hyteresis WhatIsHysteresis html What is Hysteresis 12 22 98 National Instruments LabVIEW User Manual Jan 199
28. P is 32 bits while the conversion result is 12 bits The necessary sign extension is performed internally and the user does not need to perform any such extension To read from more than one channel multiple calls to Read Adc are necessary Since the ADC on the card has four channels legal values for channel are from 0 to 3 If the voltage at the ADC input is to be calculated then the ADC output is simply multiplied by the scaling factor 5 2047 The function begins by writing the channel and the default gain of unity to the latch Once the latch is set the function waits for the conversion to be triggered by the TCLKO pin toggling This pin is the output of the Timer 0 28 Figure 4 2 Synchronization to TCLK Whenever the count is complete the pin goes high stays high for a clock period and then goes low This event is used for triggering the ADC in hardware This also is used to synchronize the software to a time source The timer runs off the DSP clock in the timer mode and its accuracy is determined by the DSP clock which is very good This is the source of timing in all the control programs written with this library 4 7 Sampling Rate Determination To use the above function calls include the file d310bio h at the start of the program It is necessary to define the sampling rate for the system This is done by defining tne constant TIMPERO The functions WriteDAC and ReadAdc both wait for the falling edge of the TCLK signal in t
29. PI control in first mode vi Diagram BEI Fie Edt Opete Project Windows Help Ler xm P ul 3p Application Fon e Roa tee 5 ait Until Next ms Multiple 3 Lt a e Eum i 3 pet KI Ts en 3 gt ec PEDE DIU REN OT EPA e nro E WAStart EHP Status Window LabVIEW ES Pt contiolin fest mo E3 PI control in firs An Snagit 32 g sse Figure 7 5 Block Diagram of PI control system completely programmed in LabVIEW MM SEY TTT TTT Seer dH P E A Figure 7 6 The Two PI control system 7 3 Drawing a Circle with PZT The use of PI control was enhanced to control two axis of the PZT structure also instead of single layered PZT we used a four layered PZT stack to draw a circle The PZT is driven by two sine waves with a 7 2 radian phase difference as in Figure 7 6 This was achieved by giving the PI controllers the sine waves as a reference The PZT was driven thus to move in a manner as to draw circles We were successful in drawing circles from 25 nano meters to almost 11 25 um However beyond this range the capacitive sensors ADC DAC and our software started to saturate and the circular motion of PZT could not be monitored properly A circle of 3 0 jim is shown in Figure 7 7 The GUI was developed to be easy to use aesthetically pleasing and accurate The experiments performed were found to give satisfactory results With extens
30. PU consists of an ALU a 32 bit barrel shifter a 32 bit multiplier Auxiliary Register Arithmetic Units ARAU s and several registers in it The multiplier performs full 32 bit multiplications in just one cycle and is capable of operation in parallel with the other components of the CPU The Arithmetic and Logic Unit ALU performs single cycle operations on 32 bit integer and 40 point floating point data The Auxiliary Register Arithmetic Units ARAU 0 and 1 generate memory addresses in one cycle for the fast generation of memory addresses in the various addressing modes The CPU also includes 28 registers in a multiport register file tightly coupled to the CPU These are used to store operands right in the CPU so that they are available for the instructions without any access delay The on chip RAM blocks 0 and 1 are each 1K x 32 bits and the ROM is 4K x 32 bits Each on chip memory block can support two memory accesses in a single cycle The instruction cache is 64 24 x 32 bits i e 64 words large and maximizes the system throughput by caching the repeatedly accessed code The cache uses the Least Recently Used LRU strategy for updating the cache memory from the main memory The TMS320C31 has a full duplex bi directional serial port The port can transfer data in 1 2 3 or 4 bytes per word The port can also be programmed in a synchronous mode where continuous transfers can be done transmitting many words of data without new synchroniz
31. Start EHP Status Bl tera Tem vs oos P LabVIEW Biss lS icio fn Snagi 32 9 1 19 PM Figure A 8 The Block diagram of the case false Resonance Frequency gt Iv_ vi Diagram Fite Edt Operate _ Windows ae e Puri eke n ves EHP sine Gy teva em BBvsv0s P Lavi Br Er tf vi D fjnSnagi v3 m 1 19PM UH 119PM Figure A 9 The Second Block diagram of the case true Resonance Frequency gt gt Iv_pi vi Diagram File Edt Operae Project Windows Help 3 ter A al I ode Interface Node as 1i Enl a BBL ena a e P ass JHP Staus rea tern soos P Lavi Bis t n Snagv32 Bran eR Figure A 10 The Block diagram of the case true Proportional Integral Control gt Iv pi vi Diagram 70 APPENDIX B THE CINS B 1 The DSP Block CIN CIN source file the DSP block The DSP is set to go then the Sampling time and the desired signal are written to the DSP DSP then writes out this value to the outside world reads a value which is then wrote back to LAbView include extcode h include lt stdio h gt include lt math h gt include lt conio h gt CIN MgErr CINRun int32 Sampling Rate int32 var2 float64 Data sent by DSP CIN MgErr CINRun int32 Sampling Rate int32 var2 float64 Data sent by DSP ENTER YOUR CODE HERE All variables used in this function are declared LDIZZIZLZIZIZLZIZLAZNZIIZDILAZELZLTALZLLZAXIL
32. ZIILIZXIEI II I I outp 0x306 PAGE VALUE outpw 0x302 KI address outpw 0x300 KI The logic to set the Bias ELLELE outp 0x306 PAGE_VALUE outpw 0x302 Bias address outpw 0x300 Bias The logic to set the KP ktt tt tpi tee eee outp 0x306 PAGE VALUE outpw 0x302 KP address outpw 0x300 KP 87 The Check is read LLELLE outp 0x306 PAGE VALUE outpw 0x302 Check Address check inpw 0x309 endwhile The Logic to read the Signal going from DSP SSS SSS SS SSS SSS SSS STS TS SSS SSS SS STS STS SS SS SST T outp 0x306 PAGE VALUE outpw 0x302 ADDRESSI ui6_bit inpw 0x300 Sign ui6_bit amp 0x0800 ul2_bit ui6_bit amp Ox07ff if sign 0 Un float64 ui2 bit 409 0 endif else ul6_bit u16_bit ul6_bit ui6_bit 1 u12 bitzui16 bit OxOfff Un float64 ui2 bit 409 0 if Un 5 0 Un 5 0 endelse The Logic to read Signal coming to DSP ti ta iiit tatti outp 0x306 PAGE VALUE outpw 0x302 ADDRESSO y16 bitzinpw 0x300 signzyi16 bit amp 0x0800 yi2 bitzy16 bit amp Ox07ff if sign 0 88 1 Yn float64 yli12 bit 409 0 endif else 1 y16 bits y16 bit y16 bitzyi16 bit i yi2 bitzyi16 bit OxOfff Yn float64 y12 bit 409 0 if Yn lt 5 0 Y n 5 0 endelse The Logic to reset the check TmIEIEDGELISiEGEIRSRIDIEILDIDIEILDIRIDIEIRI
33. _bit amp Ox0T7ff if sign 0 Range float64 y12_bit 2 5 100 0 endif else yi6_bit y16_bit yi6_bit y16_bit 1 y12 bitzy16 bit amp OxOfff Range float64 yi12 bit 2 5 100 0 if Range lt 12 5 Ranges 12 5 endelse The Logic to reset the check T ZIATIIENEZLZLZZZIIXIAXIEIIZIZXIEZXLIEII outp 0x306 PAGE VALUE outpw 0x302 Check Address outpw 0x300 0 return noErr 82 B 4 The Resonance Frequency Calculation CIN CIN source file for the resonant frequency measurement The DSP is set to go then the Sampling time is selected and PC waits for the DSP to finish and then loads all data into the LabView arrays include extcode h include lt stdio h gt include lt math h gt include lt conio h gt typedefs typedef struct int32 dimSize float64 argil i TD1 typedef TD1 TD1Hd1 CIN MgErr CINRun int32 Sampling Rate TD1Hdl DSP Input CIN MgErr CINRun int32 Sampling Rate TD1Hdl DSP Input ENTER YOUR CODE HERE All variables used in this function are declared SSS SSS SSS SSS SS SSS SSS SS SSS LS SSS SSS SSS SSS SS SSS SS int sign ul6_bit ul2_bit i n int PAGE_VALUE 0x0 ADDRESSI 0x1388 Timer_Address 0x01387 int check Check Addressz0x1386 int32 numDims MgErr err bogusError Start the DSP program execution n 0 Put the DSP to go 8 2 83 inp 0x306 Actual Data
34. am define TIMPERO 0x138 include D310BI0 H tinclude lt math h gt Hdefine PI 3 14159265358979 void main All variables are declared TIENEEZIEII ESI E EZEEIE mIIDEmm i int input pointer output pointer int timer pointer desired rate int check int bias KP KI reference double Ts ref KP dbl KI dbl double un yn yn 1 en en 1 All pointers are addressed ZEmEIEI XxImmIm mmmImecI mz Izumz biass int 0x138a timer_pointer int 0x1387 check int 0x1386 input pointerz int 0x1388 output pointer int 0x1389 KP int Oxi38b KI int 0x138c reference int 0x138d All pointers are initialized SSS SSS SSS SSS SS SS SSS SS SSS SSS timer pointer TIMPERO desired rate timer pointer check 0 bias 0 KP 20 KI21000 reference 100 en 1 20 yn_1 0 96 InitDsp WriteDAC 0 0 WriteDAC 0 1 while 1 if timer_pointer desired_rate X int p7 p7 int CTRL p7 0x28 timer pointer p7 0x20 TIMGBOSTART desired rate z timer pointer endif Ts timer pointer 3125000 0 if reference gt 2047 reference 65535 reference 1 reference reference 1 if reference lt 2047 reference reference amp Ox0000ffTF ref double 0 01 reference input_pointer ReadAdc 0 un 5 0 2047 0 input_pointer en ref un KP dbls K
35. ation pulses The TMS320C31 supports integer and floating point data Integer data types supported are 16 bit 32bit both signed and unsigned The floating point data types are short single precision and extended precision The use of floating point operations to manipulate data is of great advantage as the operation can be performed in a single cycle while freeing the user of the burden of implementing libraries to perform floating point operations The TMS320C31 has a 32 bit timer counter that can be used for various purposes It can be driven off an internal clock i e used as a timer or an external signal may be used to drive the timer thus acting as a event counter It can also generate an interrupt to the CPU The timer in the Dalanco Spry board is used to trigger the conversions of the ADC The TCLK pin is toggled to trigger the conversion The ADC performs the conversion and then sends the converted data to the TMS320C31 serial port Once the data is received the serial port may be read to retrieve the data 4 4 Initialization The Dalanco Board needs initialization at startup The ADC connects to the serial port on the DSP So the serial port and timer must be set up and also the latch on the Dalanco Spry Board must be set up For this the nitDSP function is implemented The function call prototype is void InitDSP void 25 Table 4 2 Word Format for the ADC Latch bs b2 i bo go mi mo The function b
36. bit integer type This header also defines some constants and types whose definitions may conflict with the definitions of the systems header files The names of the CIN routines are defined in the header file with words CIN MgErr it defines the word CIN as either Pascal or nothing depencing on the platform On PC the standarc C calling conventions are used The MgrErr data type is a LabVIEW data type that corresponds to a set of error codes that the manager routines return In our CIN the stdio h math h and conio h header files are also included to use the specific commands used in the CIN source code The Type TD1 is also defined as a handle which consists of an integer variable dimSize defining the number of elements in the array and arg the actual memory storage of the data elements These elements can each be accessed by argi i where i is the element number in array LabVIEW passes two pointers Sampling_Rate and voltage and reads two handles DSP Input and DSP Output from the CIN The main body of the CIN starts with defining the variables which will be used by the CIN program to exchange and manipulate the data between LabVIEW and DSP The defined variables also include the addresses in the DSP memory which the program will access These addresses are defined in Hex format The DSP is put to go or program execution mode by reading from port 0x306 It is important to note that the memory is shared between the DSP and the PC The variable
37. ceived If the Most Significant Bit MSB is one the data is negative otherwise it is considered to be positive 3 Data is then moved into u12_bit or y12 b t by masking and copying only 12 bits of data 4 If the sign is positive i e sign is 0 then the data is directly scaled and stored as the selected element 20 5 If the sign is negative then 2 s complement of data is calculated scaled and stored in the selected element Once all the data is recovered from the DSP the check flag is reset to value of zero and the DSP is halted by reading from address 0x307 Once all these steps are completed the CIN transfers the control of execution back to LabVIEW which then receives the data from CIN and displays and queries about the saving of the data CHAPTER 4 TEXAS INSTRUMENTS TMS320C31 DSP The TMS320C31 is one of the Texas instruments floating point DSP family member The TMS320C31 is a low cost 32 bit DSP that offers the advantage of easy to use floating point processor TMS320C31 features are identical to those of TMS320C30 device except that the TMS320C31 uses a subset of the TMS320C30 standard peripheral and memory interfaces It maintains the TMS320C30s performance while providing the cost advantages associated with 132 pin plastic quad flat packaging Some key features of TMS320C31 are as follows e Flexible boot program loader e One serial port to support 8 16 24 32 bit transfers e One 32 bit data bus 24 bit address
38. ctions to use the handle properly 12 3 3 Graphs There are three types of graphs supported by LabVIEW e XY Graph e Waveform graph e Intensity graph There are two type of charts supported by LabVIEW e Waveform Chart e Intensity Chart Each of these graphs and charts accept data of several types We can customize the appearance of the graph like putting grids background and graph colors label and line type etc We can also scale our graph to display the scaled data The intensity graph chart displays three dimensional data in two dimensions 3 4 Exec Function It is a special function in the communications block and runs an executable file 3 5 Fast Fourier Transform Fast Fourier Transform is used to give frequency domain representation of data LabVIEW uses the Discrete Fourier Transform DFT For a sampling frequency of f Hz then the time interval between the samples is At where 13 The sample signals are denoted by z 0 lt i lt N 1 When the DFT is given by N 1 X 2 V g e i2rikiN i 0 for amp 50 1 2 ices N 1 is applied to these N samples the resulting output X k 0 lt N 1 is the frequency domain representation of z X has frequency spacing of 1 AF gas Af is known as the frequency resolution To increase the resolution we can increase the number of samples or decrease the sampling frequency Direct implementation of DFT requires N complex operations for N samples
39. d back from A D 6 1 4 The Front Panel The front panel of the DSP block is displayed in Figure 6 1 and consists of four componen s e Control input for sampling rate e Control input for Data to be sent to DSP e Binary control button for operation during the run execution e The display for the data sent by DSP We can give integer values to the control input for the sampling rate this value is written to the CIN The control for input Data sent to DSP accepts floating point 37 MU Figure 6 1 The Front Panel of the DSP Block values for the data or the voltage level which is to be sent to the DSP the value is in volts and has the precision of two decimal places the display is also configured to display only upto two decimal places The binary button select whether we want to download the DSP program to interface with the DSP block VI into the DSP or we want to execute the program in the DSP This is done for convenience as well as better utility of the system The user is responsible to ensure that the proper interfacing program is in the DSP before executing the DSP block It is recommended that we should always download once before we actually start the program The block is configured to download the DSP program when opened and the user has to switch to execute mode before he can start using the DSP block VI The value read by the DSP is also displayed as voltage with two decimal point precision on the front panel This VI
40. d out at the slowest possible speed The sampling rate has to be given in integer form Voltage input 46 control is provided to accept voltage with accuracy of two decimal places The binary button can select whether we are going to Download the program into the DSP or we are going to execute the program in the DSP It is important to note a few things here e The display of the data on the two waveform charts consumes a lot of resources as well as time causing this particular VI to be excruciatingly slow The display will become garbled and not easily understandable at relatively higher frequenc es The fastest acceptable frequency cannot be ascertained as it depends heavily on the applications running under windows and the system hardware being used The higher sampling rate can cause the DSP and the display to get asynchronized and the realtime effect can be lost Once the sine wave cycle has completed the PZT has passed through the maximum and minimum levels of its displacement the range of PZT displacement can be read from the display Range Figure 6 3 shows the Front Panel This Vl is a stand alone VI and cannot be connected to other VI s as a sub VI It has to be run on the continuous run mode in the LabVIEW because we need to run CIN each time we need new data and also necessary to keep the realtime operation going 6 3 2 The Block Diagram The block diagram shown as Figure A 5 writes the sampling rate without an
41. e code to form executable CIN LabVIEW calls the CIN as another of its functions passing parameters to the node and accepting the data provided by the node CIN are geared for use with code or specific uses which can be accomplished more easily using the conventional programming language 11 CINs execute synchronously meaning all other LabVIEW functions are disabled However LabVIEW monitors the keyboard menus and may allow other applications to execute depending on the operating system CIN object code takes control of the processes that LabVIEW ignores keyboard events menu clicks and other diagrams A CIN appears as an icon with input and output terminals The terminals are associated with data in the Node source code and block diagram LabVIEW calls the code and passes the specified data The interface for CINs and external subroutines supports a variety of compilers Using CIN involves following steps e Pace the CIN on block diagram e Create the necessary input output connections Create a C source code Compile the source code e Link the code to CIN LabVIEW passes data by reference to the CIN LabVIEW passes numeric data types to CINs by passing a pointer to the data as an argument LabVIEW stores Boolean in memory as 16 bit integers and passes them same as numeric Cluster is passed by passing a pointer to a structure containing the elements of the cluster LabVIEW passes array by handle LabVIEW also provides some fun
42. egins by setting up a few pointers The latch in the Dalanco Spry Board contains the ADC channel number and the gain for the programmable gain amplifier PGA This latch is set up as a default to set the ADC channel to 0 and a unity gain for the programmable gain amplifier These are just the defaults by accessing the latch before each conversion the user can set the gain for the PGA as well as set the channel The function ReadAdc takes care of the function of setting the channel Tne word format for tne LACCH VAL word is shown in Cable 4 2 The bits g and go set the gain of the programmable gain amplifier PGA while the bits m and mo set the channel for the ADC multiplexer The PGA gain is set by the value of the word gi9o i e 002 110 012 1045 102 10019 and 112 100039 The ADC channel gets set to the value of the word mimo i e 002 0 5 015 lio 102 210 and 11 310 The other bits in the LATCH VAL are don t cares Following this the function now sets up the DSP chip registers itself The registers set up are the Timer registers and the Serial port control registers In the C31 these are memory mapped To do this a pointer is set up to the register area which in the C31 is at 80800015 and the values are written to the registers This sets up the DSP to ADC communication on the serial port The Read Adc and WriteDAC functions can now be called to perform analog I O as desired 26 4 5 DAC Usage T
43. emperature Effects 2 00 605 oe ee e ee SN 35 5o Out Planb vao ane dre dos CD Y eoe SU RR afe a Baw ad Sa 35 6 IMPLEMENTATION cupa exceeded gale NO SCR ORO deat Sava ele pe RN 37 Bl Tbe DSF Boce Lu gore D extr Ce Cede cent GM Re dos cca etat oss 37 5 ll The Front Panel cs 6433 900943 doy dur vC ACE ee PX PATE 3T 5 L2 The Block Diagral uade deeem exe E edo RUN 39 NS MES NT OD M rc Aree aa er eo EC 39 p 1 4 The DSP Program est be bse pe ee eR RA EE 40 6 2 Hysteresis with Dither ous os RE beg X ee ae a el 40 DAT The Front Panel 2 6 2 4 0 ie eee de REL d SES 40 0 2 2 The Block Diagram 25 ed wha yt ace A ie 42 D 2 de Pie OIIN ns cou dug he enue cuter on Eno eo dd cere fex et iles d 43 0 2 4 The DSP Program 2 2 ue aie OR m oe e v dns 44 6 3 Range of PZT Displacement 2 xo ku e RR EE RE 44 God The Front Panel 221454449 Pes tte ed ACE 44 Chapter Page 0 9 2 The block Diagram dune rri eee RA EO E Reg 46 93 9 The CIC asd Bice he c det eds md Noa e eaa 4T 634 The DSP Programi xx 64 ha See XE was des 4T 6 4 Resonant Frequency Determination llle 48 GAT PhecEront Panel secs aceto mou o ATER OR SE e as 49 64 2 The Block Diagram eges ed eso vee ee keen A 50 Dd ThE CIN ui osos eu 20 eee hte CP hos n dU obs inae ao 51 644 The DSP Program 549929499 Res base te Sea kes SE 51 6 5 PI Control Application 0 0 0 ee ee ee 51 6 5 1 The Front Panel 22 nere Ree nd heh eed Rae oov 52 5 5 2 The Block
44. esponse exhibits hysteresis type of nonlinearity This hysteresis loop has more of a ovular shape than the classical hysteresis shape A dither is a high frequency signal introduced into a nonlinear system in order to linearize its performance By sweeping back and forth quickly across domain of a 59 Y axis without Dither Y axis with small Dither Displacement Displacement 1 2 3 3 2 1 0 0 Voltage Voltage Y axis with medium Dither Y axis with large Dither Displacement 2 1 0 Voltage Figure 7 3 Dithering in the Y axis of Plant nonlinear element a dither sort of averages the nonlinearity This averaging action can reduce the nonlinearity in the system We calculated the dither by selecting the frequency of the most prominent resonance mode and dividing it by the bandwidth required for a 3 dB drop This gave us the Q factor Then depending on this Q factor we calculated the approximate voltage to introduce different magnitude dithers into our system We used iae for 1um small 5um medium and 10um large dithering signal Dither has the effect of attenuating the harmonic components of the funda mental waveform applied to it The effects of the dithering on the harmonics were checked using the VI for Resonant Frequency response A sine wave of 1 volt amplitude was applied and the harmonics introduced by the nonlinearity of the PZT were attenuated using the dithering One of the results of dithering is shown
45. f operations as much as possible between different layers of application 2 3 GUI Implementation System is decomposed for implementation There can be different approaches of decomposition like e Functional decomposition Data flow decomposition Entity relationship decomposition e Object oriented decomposition Tne subsystems based on any of the decomposition models are all inter connected in some fashion These interactions influence the runtime dynamics of the system Each of the decomposition may employ more than one interfacing mechanism Some of the basic interfacing mechanisms worth mentioning are e Sequential procedural call e Message passing e Event Responses A GUI application consumes extensive graphical resources The performance depends on the following e Windows Windows 95 LabVIEW Figure 2 1 The Block diagram of data flow e mouse pointer e cons and Bitmaps e Colors e Fonts and Text strings e Graphic drawing primitives 2 4 Our GUI Structure We used LabVIEW version 5 running on a Windows 95 operating system The attached Figure 2 1 represents the data flow for our GUI software Windows 95 was selected as an operating system to run the LabVIEW meaning the monitor keyboard mouse timing of operations and all operating system components are commanded and controlled by Windows 95 LabVIEW hands over all it needs to display at monitor to Windows 95 and receives all keyboard and mouse instr
46. g and writing to the DSP needs some explaining 1 Page Value is written at port 0x306 this operation is carried out by using the outp command This needs to be carried out specifically every time we wish to read or write to the shared memory as DSP also is accessing this memory and the page Value keeps changing automatically 2 The Address of the memory location is written to the port 0x302 the command outpw is used 3 The actual data is writen to or read from the address 0x300 we have used the outpw and inpw commands to read and write the data Once the DSP has completed its execution of routines to perform the test and acquired the necessary data it tells CIN to read the data by giving a value of 1 to the check flag The CIN then moves on to the for loop in which the collected data is read from the DSP The data is read as 16 bit unsigned integer by the inpw command This raw data needs to be manipulated in order to extract the actual data which 19 Amplifier sensor Figure 3 4 The Block diagram of the input output was stored by the DSP in its memory location The DSP stores the data in 32 bit memory locations The process of decoding the read data is 1 The data is stored in the memory locations u16_bit or y16_b2t depending on where it goes y is the output from the sensor and u the input to the amplifier The whole flow is expressed more elaborately by the Figure 3 4 2 First we find out the sign of the data re
47. h the LabVIEW PI control VI 6 5 3 The CIN The CIN accepts the data from the LabVIEW and passes it to the DSP then it waits for the DSP to signal via check flag that it has actually carried out one sampling of I O data Then the y n and u n are read from the DSP and transferred back to LabVIEW and the check flag is reset for another operation to be repeated 55 6 5 4 The DSP Program The DSP program accepts bias at address 0x0138a sampling time at address 0x01387 check flag at address 0x01386 u n is handled at address 0x01388 and y n is handled at address 0x01389 KP at address 0x0138b KI at address 0x0138c and the reference at address 0x0138d The sampling time T is calculated The error e n is calculated as difference between the reference and the feedback from plant KP and Ki are scaled and then the output for the plant is calculated as y n y n 1 KP KIT e n KPe n 1 then y n is scaled to stay within bounded limits and the values of y n and e n are recorded as y n 1 and e n 1 for the next sampling Finally the check flag is set to inform the CIN that the DSP has completed the task assigned CHAPTER 7 CONCLUSION The goal of our work is to simplify and improve the speed of the experiment Developing a Graphical user interface using DSP for data acquisition and control applications and the interface for data display and analysis We were able to reduce the experiment duration for carrying out a
48. he C31 DSP A sequence RWWRR synchronizes up as shown in Figure 4 2 This means that the sampling rate is determined by the value loaded into the Timer 0 of the C31 Also since these functions wait for the falling edge all the reads and writes get synchronized to these falling edges The Figure 4 2 shows an arbitrary sequence of reads and writes as it would get executed The function InitDSP puts TIMPERO into the Timer 0 count register The constant must be defined before the file d310bio h is included so that the default value is not picked up The value of TIMPERO is calculated from SystemClock SampleRate Trg PERO numcalls 8 29 M RI R2 Wl W W3 W4 Figure 4 3 Successive Read and Write Events where System Clock 50M Hz The factor numcalls is the total number of calls to the functions ReadAdc and WriteDAC in one execution of the control loop This is to account for the fact that both functions wait for the falling edge of TCLK So for example if TCLK has a frequency of 1kHz and if the control loop has one ReadAdc and one WriteDAC then the loop will run 500 times per second The functions WriteDAC and WriteDACS must be distinguished with care as illustrated in Figure 4 3 The writes W1 and W2 are made using WriteDAC The writes W3 and W4 are mace with the function WriteDACS Owing to the arcnitecture of the board such paired writes may be made but paired reads are not possible The functions thus isolate the user from the u
49. he output to the analog channels is written via the DAC The function call for this is WriteDAC The C prototype for this is int WriteDAC int value int channel This outputs the value to the DAC channel specified Since the DAC has two channels legal values for channel are 0 and 1 The value passed may be in the range 2047 If the value is greater than 2047 it is clamped off to 2047 and if less than 2047 is also restricted to 2047 This clamping is done by the function WriteDAC and need not be performed by the user This is to avoid problems associated with roll over If the value is greater than 2047 then it cannot be properly expressed in 12 bits and leads to wrong interpretation of the value Thus if a value of 4096 1s output to the DAC with an intended output value of 10V it gets clamped to 5V only since the DAC output is restricted to 5V Similar clamping occurs on tne negative side The function WriteDAC retains the value output to the DAC channel 0 and channel 1 For this reason the declaration for channel value is prefixed with static The reason for maintaining the last value is that actually every time the DAC value is updated both the DAC values are to be written In C it is made to appear as if each DAC is written to separately While this is more convenient to use it means that the function WriteDAC must know the value of the other DAC previously written If this value is not stored then when one DAC is wri
50. her than a triangular waveform in practice a sampling rate of 50 samples per second was found to be a good selection The DSP program writes the calculated value out in array starting from address 0x02788 and then copies the value from A D converter to the array at address 0x01388 onwards One the complete route for the hysteresis is completed the DSP program sets the check counter thus informing the CIN that it has completed the data acquisition for the desired experiment 6 3 Range of PZT Displacement 6 3 1 The Front Panel The range of the PZT plants displacement is measured by giving very low frequency sine wave input to the DSP and reading the maximum and minimum voltage levels and scaled to displacement Therefore we have the following on the front panel e Control input for desired frequency of sine wave e Control input for sampling rate i gt dv ran vi Figure 6 3 The Front Panel of the PZT Range e Control input for Voltage level to be used during the experiment e Control input for bias level to be used during the experiment e Binary control button for operation during the run execution e The Waveform Chart to display the signal written by the DSP Incoming Signal e The Waveform Chart to display the signal coming back to the DSP Outgoing Signal e The Calculated range We can give frequencies with an accuracy of two decimal places the fractional Hz capability is necessary since the experiment needs to be carrie
51. ial 31 32 5 2 Advantages of Piezoelectric Positioning Systems The advantages of piezoelectric positioning systems are e Unlimited Resolution A piezoelectric actuator PZT can produce extremely fine position changes down to the subnanometer range The smallest change in the operating voltages are converted into smooth movements Motion is not influenced by striction friction or threshold voltages e large Force Generation PZTs can generate forces in levels of 10 000 N e Fast Expansion PZT offers fastest response time acceleration rates of more than 10 000 g s can be obtained e No Magnetic Fields The PZT is related to electric fields and don t produce any magnetic fields or interact with any magnetic field e Low Power Consumption The PZT consumes energy only during the motion static operation even under heavy loads does not consume power e No Wear And Tear PZT does not have any moving parts which will wear and tear and need routine maintenance It therefore can give satisfactory performance over a long duration of time without any replacement e Vacuum and Clean Room Compatible PZT does not need to be lubricated and does not wear or abrase thus is suitable for vacuum and clean room applications 33 e Operation at Cryogenic Temperatures The Piezo effect is based on electric fields and functions down to almost zero Kelvin with reduced specifications 5 3 Displacement of Piezo Actuat
52. if timer_pointer desired_rate 92 93 int p7 p7 int CTRL p7 0x28 timer_pointer p7 0x20 TIMGBOSTART desired rate timer pointer endif Ts timer pointer 3125000 0 theta double 2 PI frequency 100 0 n Ts l input pointer int voltage 409 100 sin theta bias 409 100 ntt if theta 2 PI n 0 WriteDAC input_pointer 0 output_pointer ReadAdc 0 if theta gt PI 2 k output pointer gt max max output_pointer if theta gt 3 PI 2 amp amp output pointer min min output pointer if max min gt 0 range max min 100 409 check 1 endwhile endmain 94 C 4 The Program for Resonance Frequency define TIMPERO 0x7a12 include D310BIO H void main 1 int input pointer int timer pointer desired rate int i check timer pointerz int 0x1387 check int 0x1386 timer pointer TIMPERO desired rate timer pointer input pointers int 0x1388 InitDspO WriteDAC 0 0 WriteDAC 0 1 checkz0 while 1 for 1 0 i lt 5000 i if timer_pointer desired rate 1 int p7 p7 int CTRL p7 0x28 2 timer pointer p7 0x20 TIMGBOSTART desired rate timer pointer endif input_pointer ReadAdc 0 WriteDAC 0 0 input pointer t endfor check 1 endwhile end main 95 C 5 The Proportional Integral Control Progr
53. in Figure 6 4 60 Table 7 2 Effects of Dithering on Harmonics Frequency 0 0064 Hz 0 192 Hz 0 256 Hz 43 dB These results in Table 7 1 point to the fact that we need a bigger dithering amplitude to completely attenuate the harmonics on the other hand bigger dithering also causes a lot of additional oscillations to be introduced into the system The ideal amplitude of the dither cannot be ascertained 7 2 PI Completely Programmed in LabVIEW A complete PI control algorithm was implemented in the LabVIEW using the DSP Block VI as a subVI to implement a single loop PI control The maximum operating frequency was 1000 samples per second the PI algorithm was developed with a built in one sample delay The DSP Block gave us the values of the Un and Yn which were stored in the shift registers Thus using the yn 1 yn 2 en 1 and en 2 to implement the discretized PI control completely in the LabVIEW The Block diagram is available in Figure 7 5 The usual Sampling rate Operation contrl KI KP Yn Un and a chart diplaying the current status were implemente din the front panel as in Figure 7 4 bi PI control in first mode_vi Ele Edt Operate Project Windows Help IS T T3ptAppication Font ox 3s 21 gt ETE FE al WAStart EHP Status Window Labview ES Pt control in firs E PI controlin fest mo a n Snagit 32 gj sso Figure 7 4 The PI control system completely programmed in LabVIEW P
54. is set and from this sampling rate information the sampling time T is calculated The 0 1s then calculated as follows 6 2m f t 2n fn 1 This theta is then used to calculate the sine waveform and the sine wave is multiplied with the desired voltage and the bias is added before it is sent out to the 48 plant The number n is incremented each time until the 0 reaches a value of 2 7 then n is reset since sin2dr sinl The range is calculated as the difference between maximum and the minimum voltage sensed by the PZT displacement sensor scaled and then written to the address 6 4 Resonant Frequency Determination The conditions of dynamic stability instability are commonly expressed in mechanics of vibrations in terms of frequency relationships and the related mechanical phenomenon is called resonance Systems with constant coefficients in their DE s have most generally the frequency relationship of form v p q w where v is the excitation frequency w is one of the natural frequencies and p and q are usually small relatively prime numbers The motion of the system in the vicinity of v are resonance oscillations with amplitude a of one mode corresponding to the natural frequency w The frequency v is called the critical frequency For the systems whose governing DEs of motions have periodic coefficients the frequency relationships are of the following form v 1 p wi wj and for nonlinear systems k
55. ive data exchanging and data conversions during the data transactions and also the use Iv pi2 vi RS Senses Se Ss See of 12 bit capability of the DAC ADC we were able to perform operations with 95 accuracy in the worst case scenarios The future of the work can span more experiments to be incorporated in the system The improvement of the graphic display experiments developing and imple menting the experiments using the DSP Block which do not need any code to be written in the DSP Incorporating other control algorithms Studying and further improving the dithering technique for the PZT Improving the performance of the interface to higher frequencies of data exchange APPENDIX A THE BLOCK DIAGRAMS 64 dsp block vi Diagram De EA Opewde Dopo Windows Hep 5 0 0 5 0l aln Data sent by DSP bee ECSCM HU ER a Start EEJHP Status LabVIEW Beso block vi Byte tem ie 5205 P ES dep bloc fn Snagit 32 1210 Figure A 1 The Block diagram of the case true DSP Block 4 gt dsp block vi Diagram File Edt Operate Project Windows Hep m aes muU HEART Command com c dsp bat listen EHP Status Lave E dp biockvi Bl Tora Tem lbs Dos P E dsp bioc tanSnagit 32 TOES Figure A 2 The Block diagram of the case false DSP Block Hystetises vi Diagram F e Edt Operate Project Windows Hep Seen SSE
56. n the DSP gives the check flag the values for input are read and the check flag is reset Finally the DSP is halted before the CIN is finished 6 4 4 The DSP Program The DSP checks and keeps the sampling rate to the desired sampling rate as given by the CIN Then it collects data from the input and once all required data is accumulated the DSP sets the check flag 6 5 PI Control Application PID controllers are the most widely used practical controllers The textbook version can be described by equation de t dt iske F J EEN where e is the error difference between command signals u the setpoint and process measured output y K is the gain or proportional gain of the controller T the integration reset time and T the derivative time A pure derivative cannot be implemented because it will give a very large amplification of measurement noise With this perception only a PI controller was implemented in our case 52 The controller can be discretized using any of the standard methods such as Tustin s approximation or ramp equivalance Tutsin s approximation gives a behaviour such that the pole goes to 1 as T4 goes to zero The control signal is given as u nT P nT I nT D nT It has the advantage that all three terms can be calculated separately The incremental algorithm is obtained by rewriting the control algorithm such that its output is the increment of the control signal Au can be calculated as
57. ndif else i u16 bitz ui16 bit u16 bitzui6 bit 41 u12 bitzu16 bit OxOfff DSP Input argi i 2 float64 u12 bit 409 0 if DSP Input argi i l lt 5 0 DSP_Input gt argi i 5 0 endelse Signal sent to the DSP by the sensor is store in Array DSP_Output outp 0x306 PAGE VALUE outpw 0x302 ADDRESSD i 77 y16_bit inpw 0x300 Sign y16_bit amp 0x0800 yi2_bit y16_bit amp OxOTff if sign 0 DSP_Output gt argi il float64 yi2 bit 409 0 endif else i yl6 bit z y16 bit desired negative output voltage 0 5 yi6 bitzyi16 bit 41 y12 bitzyi6 bit amp OxOfff KDSP Output argi i float64 y12 bit 409 0 if DSP_Output gt argi i lt 5 0 DSP_Output gt argili_ 5 0 endelse endfor Check is reset to 0 outp 0x306 PAGE VALUE outpw 0x302 Check Address outpw 0x300 0 Halt the DSP program execution mImmmmEmirzmImmImcmmmezI zmecimmzcI m inp 0x307 return noErr out return err end CIN 78 B 3 The Displacement Measurement CIN CIN source file for the PZT movement range measurement The DSP is set to go then the Sampling time and the desired signal are written to the DSP the DSP then writes out this value to the outside world reads a value which is displayed on the chart it also calculates and transfers the range of the readings include extcode h include lt stdio h g
58. ned to allow multilayer stack of PZTs also to make it easy to test them individually We usec individua PZT s to gather information about there performance and then made a four layer PZT plant to do our PI control experiment The PZT is excited by using a 1 100 ratio DC amplifier to amplify the DSP outputs of 5V The displacement sensing of the PZT behaviour is carried out by using a capacitive sensor The gain of the capacitive sensor is 0 4 The capacitive sensor is excited by a separate power supply of 5 volt DC and gives the deflection in the 36 range of apprx 12Vdc Our range of expected sensing is well within the capabilities of the capacitive sensor The whole system is capable of working at 5 volt for communicating with the Delanco Spry 310 board The board then transfers the data onwards to LabVIEW for further processing CHAPTER 6 IMPLEMENTATION 6 1 The DSP Block The DSP block of the is a VI which can be run at its own as well as connected to other VIs as a subVI It has an icon which allows it to be connected to three inputs and give one output The required inputs are e Sampling rate and integer input e Download Execute selection a binary selector input e Input the data value that has to be written to the DSP and e Output the data returned to the LabVIEW by the DSP When this is run at its own its front panel can be used to give and read the status of the DSP what we are writing to D A and what is being rea
59. nnecessary details of the board architecture but reflect the restrictions that the architecture imposes on the operations to be performed The sampling rate may also be set dynamically as explained in the following section 4 8 Runtime Sampling Rate Determination As explained in the previous section the sampling rate is determined by the count in the Timer 0 Period Register of the C31 This value is set up by InitDSP but it can also be altered within the program if the need arises For this the memory mapped Timer Period Register must be altered This can be done very simply as follows int period period int 0x8008028 period TIMER PERIOD DESIRED 30 This changes the rate at which TCLKO pulses and sets the rate for the reads and writes Note that if this is to be done repeatedly e g to generate a rectangular wave duty cycle not 50 at the output of the DAC then for good accuracy it would be necessary to start and stop the timer while this is done and also to synchronize the modifications with TCLK itself 4 9 Data Exchange between the PC and the DSP Card The data exchange between the DSP card and the host PC is accomplished by calling the functions in the user library provided by the card manufacturer For more detailed information consult the users guide for the card CHAPTER 5 THE PLANT PZT Piezoelectricity means pressure electricity Pierre and Jacques Curies discovered it in the 1880 s It is the propert
60. o save the data in the form of a spreadsheet file The Front panel of the system is displayed in Figure 6 1 In addition to these developed graphical interfaces LabVIEW also gives the user some commands like the run continuous run stop and pause buttons The user can also change the screen as to personal needs CHAPTER 3 LABVIEW 3 1 G Programming G is the programming language of LabVIEW G is a general purpose programming language with extensive libraries of functions for any programming task G includes libraries for data acquisition GPIB and serial communications data analysis data presentation and data storage Conventional program debugging tools are also included so we can set break points animate the execution to see the data processing and passage as well as single step through the program to trap exact locations of errors and for easier debugging However G differs from other languages in that it has graphical interface with the user rather than a text based interface G programs are called Virtual instruments due to their appearance and performance as imitating instruments VI are similar to functions of other programming languages A VI consists of three parts the user interface for human users the icon connections for embedding the VI as a subVI and its source code in the form of a wired Block Diagram This relationship is further elaborated in Figure 3 1 With these features G makes use of the concept of modular prog
61. o download the 42 DSP program to interface with the DSP block VI into the DSP or we want to execute the program in the DSP The user is responsible to ensure that the proper interfacing program is in the DSP before executing the Hysteresis VI It is recommended that program should always be download once before we actually start The block is configured to download the DSP program when opened and the user has to switch to execute mode before he can start using the VI Once the DSP has carried out the exper mer and kad the data rarsferred to the LabVIEW tke data is plotted or the XY graph and the user is a asked if data needs to be saved The arrays of both the DSP input and DSP output are also available in the displays for these purposes This VI can be run only once or can be put into repetitive runs from the control toolbar on LabVIEW This VI cannot be used as a subVI but only as an independent VI The execution time depends not only on the systems performance but also on the sampling rate being used 6 2 20 The Block Diagram Once again the block diagram as shown in Figure A 3 consists of a true false case selection controlled by the Download Execute button The true case block diagram shows the sampling rate is directly transferred to the CIN while the voltage is scaled by a factor of 409 0 and then transferred to the CIN The voltage has accuracy of two decimal places as it is transferred to the CIN The CIN in this case writes back two
62. ol toolbar on LabVIEW The modes of frequency display are prominent high amplitude peaks which stand out in the frequency domain display Single sided FFT is carried out and the results are plotted for a sampling of 8192 data points 6 4 2 The Block Diagram The block diagram shows that the Sampling rate is written as it is to the CIN The CIN has one output only terminal The data sent by the DSP is available at the output only terminal and is already properly scaled to give the voltage read by the DSP This data is collected by LabVIEW in the form of an array and then the FFT operation is performed as well as this data is displayed in the time domain data display screen The array size is determined and then the single sided data for frequency domain display is extracted Then this data which is in real and imaginary parts is processed for amplitude and phase calculation by the complex to polar VI The resulting data is divided by 2 if nonzero and then a cluster is formed 51 which is given to the frequency domain display graph Figures A 7 A 9 show the Block diagrams Incase of the case false input from the download execute button the block diagram shown in the Figure A 8 in appendix A is executed This calls the batch file range bat which compiles and downloads the DSP program to interface with the LabVIEW DSP block VI 6 4 3 The CIN The CIN puts the DSP in execute mode and then writes the desired sampling rate to the DSP Whe
63. oltage 1 2047 5 while 1 for i 0 i lt 2047 i if timer_pointer desired_rate int p7 p7 int CTRL p7 0x28 timer pointer p7 0x20 TIMGBOSTART desired rate timer pointer endif if 14410 input_pointer i Going upto 1 volt if 15409 i lt 1227 input_pointer input_pointer 1 1 if i gt 1226 amp amp i lt 2047 input_pointer input_pointer 1 1 output int input_pointer voltage 409 WriteDAC output 0 output_pointer ReadAdc 0 input_pointer output_pointer if i 2046 1 input pointer int 0x1388 output pointerz int 0x2788 endif endfor check 1 endwhile 91 C 3 The Displacement Calculation Program define TIMPERO 0x138 include D310BIO H ftinclude lt math h gt tdefine PI 3 14159265358979 void main X int input pointer output pointer int timer pointer desired rate int check range max min n int frequency bias voltage double theta Ts frequency int 0x138b bias int 0x138c voltage int 0x138d timer_pointer int 0x1387 check int 0x1386 range int 0x138a input_pointer int 0x1388 output_pointer int 0x1389 timer pointer TIMPERO desired rate timer pointer InitDsp WriteDAC 0 0 WriteDAC 0 1 check 0 range 0 frequency 5 bias 0 voltage 1 WriteDAC 0 0 max 0 min max n 0 while 1
64. ors Open loop Piezo actuators exhibit hysteresis like magnetic devices this can be eliminated by closing the loop Hysteresis is based on crystalline polarization effects and molecular friction The absolute displacement generated by an open loop PZT depends on the applied electric field and the piezo gain Piezo gain is effected by the electric field piezo its deflection depends on its previous operating conditions Hysteresis is typically of the order of 10 to 15 of the command motion 5 4 Considerations for PZT Usage 5 4 1 Mechanical Considerations Every time the PZT drive voltage changes the piezo element changes its dimensions if not blocked Due to the inertia of the PZT mass plus any additional mass a rapid change will generate a force acting on the PZT The maximum force is approximated as Paz RS krAL Maximum force available to accelerate the PZT where AL maximum displacement without external force and kr PZT actuator stiffness Tensile forces must be compensated to prevent damaging the PZT Sinusoidal operation with frequency f and the amplitude AL 2 peak forces can be expressed as Pus 4rmesslAL 2 f 34 PZT plant Amplifier LabVIEW Capacitive Sensor TM5320C31 Figure 5 1 The Block diagram of our plant Fayn is the dynamic force mess effective mass AL peak to peak displacement and f the frequency in Hz 5 4 2 Electrical Considerations When operated far below resonan
65. ough the C31 The DAC is capable of outputting at a maximum rate of 140kHz The ADC has a maximum conversion rate of 300kHz The voltage ranges for the ADC and the DAC are 5V A block diagram of the Dalanco Spry Data Acquisition and Signal Processing Board Model 310B is shown in Fig 4 1 The DSP can be programmed in C as well as Assembly and the DSP Development system is completely compatible with the Texas Instruments Optimizing C compiler for the TMS320C31 It was however necessary to create a couple of libraries so that all the coding could be done in C with the user completely insulated from the architecture of the board The DSP application board also has a programmable gain amplifier that 23 Table 4 1 TMS320C31 Characteristics Cycle time for single cycle execution Floating point processing speed 50 MF LOPS struction execution rate 25MIPS gives a software programmable gain ranging from 1 to 1000 facilitating the handling of signals with small amplitudes The gain to be used is output to the latch along with the channel number 4 3 The TMS320C31 Digital Signal Processor The TMS320C31 is a floating point 32 bit DSP from Texas Instruments Its key specifications are listed in Table 4 1 The TMS320C31 has besides the CPU a DMA controller an instruction cache RAM ROM Serial port Timers etc all integrated onto the chip This translates into very high performance for the user The TMSC320C31 C
66. ov krwr rcl which is a linear combination of v and natural frequency w where k is a positive integer and k are integer Practical steps in solving the problems of resonance oscillations are gt hespec vi Set up DEs of motion Obtain and normalize temporal DEs of motion Apply asymptotic representations of solutions Solve DEs for phase and amplitudes Determine stable unstable regions e Discuss effects of various system and external excitation on resonance modes of resonance oscillations 6 4 1 The Front Panel The front panel of the resonance frequency determination is displayed in Figure 6 4 and consists of four items 50 e Control input for sampling rate e Binary control button for operation during the run execution e The graph displaying the data gathered in time domain e The display data gathered in the frequency domain We can give integer values to the control input for the sampling rate this value is written to the CIN The binary button select whether we want to download the DSP program to interface with the DSP block VI into the DSP or we want to execute the program in the DSP It is recommended that we should always download once before we actually start the program The block is configured to download the DSP program when opened and the user has to switch to execute mode before he can start using the DSP block VI This VI can be run only once or can be put into repetitive runs from the contr
67. quired to carry out a simple test by eliminating the need to use different platforms to develop and execute the DSP program and then collect data and finally to analyze the data GRAPHICAL USER INTERFACE FOR THE DSP USING TEXAS INSTRUMENTS TMS320C31 AND LABVIEW by Tahir Nazir A Thesis Submitted to the Faculty of New Jersey Institute of Technology in Partial Fulfillment of the Requirements for the Degree of Master of Science in Electrical Engineering Department of Electrical and Computer Engineering May 1999 APPROVAL PAGE GRAPHICAL USER INTERFACE FOR THE DSP USING TEXAS INSTRUMENTS TMS320C31 AND LABVIEW Tahir Nazir Dr Timothy N Chang Thesis Advisor Date Associate Professor of Electrical Engineering NJIT Dr Marshall Kuo Committee Member Date Professor of Electrical and Computer Engineering NJIT Dr Dao Chuan Douglas Hung Committee Member Date Associate Professor of Computer amp Information Science NJIT BIOGRAPHICAL SKETCH Author Tahir Nazir Degree Master of Science in Electrical Engineering Date May 1999 Undergraduate and Graduate Education e Master of Science in Electrical Engineering New Jersey Institute of Technology Newark NJ 1999 e Bachelor of Science in Electrical Engineering University of Engineering and Technology Lahore Pakistan 1991 Major Electrical Engineering lv To my family friends and teachers ACKNOWLEDGMENT I would like to express my deepest appreciation
68. r GUI interfaces with the user The survey part of our development life cycle is that we need an experiment to determine the hysteresis characteristics of a plant Study and analysis of our problem reveals that we would like to control the sampling rate of the DSP while performing the experiment and thus put an integer sampling rate control on our screen We would also like to control the applied voltage range for which the DSP will perform the Hysteresis test Our DSP can deliver upto 5 volts hence a floating point control for voltage is also placed on the screen We also determine to give the operator the capability to Download the program of DSP into its memory or to execute the program already in the DSP memory We also need some feedback to be given to the user and display the results Two forms of displaying the results are selected e Graphically e As data displays Graphically the data of the test is displayed in the form of an XY graph displaying the relationship between the output vo_tage anc the displacement of the system Output voltage is used for X axis and displacement for Y axis In addition the array of data received by the LabVIEW is also displayed in the form of two array displays so the exact value of the graph points can be read directly from these data displays It is also realized that the user might need to save the test results as a reference for a later date therefore the program also asks the user if he wishes t
69. ramming Distributing the tasks into subVIs which collectively perform the desired task in the block diagram program of the main VI We can also print our program documentation directly from the LabVIEW We can print the active window as well as a complete set of documentation The print documentation feature offers us a number of printing options and also a number of printing destinations Another unique feature provided by the LabVIEW is the performance profiler tool This tool informs us where our application is spending time and the memory it is using This information is invaluable to identify the hotspots of our application 9 10 Front Panel Block Diagram Figure 3 1 Block Diagram depicting LabVIEW VI structure and to optimize our program This feature informs us the total time spent by our VI the time spent by our subVIs number of runs for the VI average amount of time spent by the VI Shortest and the longest time spent by our VI Time spent on executing the block diagram time spent on updating the front panel interfaces time spent in drawing the front panel of the VI Memory information is provided for average bytes used minimum bytes used maximum bytes used average maximum and minimum memory blocks used by our VI 3 2 Code Interface Nodes A Code Interface Node CIN is a block diagram node associated with a section of source code written in a conventional text based programming language We compile and link th
70. refers to a two dimensional array you pass a value of 2 for numDims The variable dataHP of ertcode h defined type UHandle is a pointer to the Handle we want to resize The variable totalNewSize gives the NumericArrayResize the new number of elements to which the the handle should refer For a unidimensional array of 5 elements we pass 5 For a two dimensional array of two rows by three columns we pass 6 Caution and care needs to be taken in the use of NumericArrayResize function because LabVIEW allocates memory array for the CIN and in case of 18 any misalignment or differences in the way data is handled and manipulated by LabVIEW or CIN can cause LabVIEW to cause system fault and be shutdown by Windows We have used this in an if statement to terminate the CIN program execution in case the NumerizArrayResize function returns an error Once we have used NumericArrayResize function to allocate memory both in CIN and LabVIEW for our array of data we can define dimSize for our handle It is important to note that this is not done by the NumericArrayResize function Now we have defined and declared all the data and memory allocations and we can concentrate on actually acquiring the data from the DSP We first wait for the DSP to complete its task this waiting is controlled by the while loop During this waiting period we write the Sampling rate and desired voltage data to the DSP and read the status of the check flag The process of readin
71. s has the purpose of providing guidelines as to user and user activities To develop user profiles the analysis looks at the users frequency of operation computer skills and general capabilities as to the system Software design activity consists of decomposing the system into smaller easily manageable sub systems For GUI applications acopting a dialog incependent software would require partitioning the system into GUI and application functional core subsystem The subsystems can then be developed separately Implementation activity involves actual coding and integration of the subsystems into a complete functional system Testing can be started once the complete system has been implemented A test plan is developed with a set of exercises for the system to perform These exercises verify that the system performs to the desired specifications and requirements 2 2 GUI Development User role is very dominant in the success of the GUI systems We prioritize classes identify concurrent classes and prioritize the task scenarios in the task model We consider the system level design for error prevention and recovery behaviour The results of analysis activities may need revision with time based on new findings Task 4 model is revised to verify that the new finding don t need redesign of the task model We then map our user interface to style specific GUI designs We identify common interaction models We attempt to retain the similarity o
72. t include lt math h gt include lt conio h gt CIN MgErr CINRun int32 Sampling_Rate int32 Frequency int32 Voltage int32 Bias float64 Incoming Signal float64 Outgoing Signal float64 Range CIN MgErr CINRun int32 Sampling_ Rate int32 Frequency int32 Voltage int32 Bias float64 Incoming Signal float64 Dutgoing Signal float64 Range All variables used in this function are declared SSS SSS SS SSS SSS SS TSS SSS SSS SSS SSS SSS ST TV SS SST SS SSS SS int sign ul6_bit u12 bit y16 bit y12 bit Data handling with signed numbers int PAGE_VALUE 0x0 ADDRESSI 0x1388 ADDRESSO 0x1389 Timer_Address 0x01387 int check Check_Adcress 0x 1386 Range_Address 0x138a int freq_address 0x1i38b bias_address 0x138c Voltage_address 0x138d Start the DSP program execution SSS SSS SSS SS 5555252555255 0 inp 0x306 Check if the DSP is done Rate x8 2 79 SSS SSS SSS SS SS SS SS SS SS SS SS while check 1 The logic to set the frequency SSS SSS 5522552252522 E55 outp 0x306 PAGE VALUE outpw 0x302 freq address outpw 0x300 Frequency The logic to set the sampling rate outp 0x306 PAGE VALUE outpw 0x302 Timer Address outpw 0x300 50000000 Sampling The logic to set the Voltage SE tiii itiiti iii outp 0x306 PAGE VALUE outpw 0x302 Voltage_address outpw 0x300 Voltage The logic to set the Bias E
73. t frequency PZT behaves like a capacitor where displacement is proportional to the charge PZT actuator stacks are assembled with thin wafers of electroactive ceramic material electrically connected in parallel A measure of stack capacitance can be made by C rz nEoE33 d n is the number of layers o dielectric constant in vacuum 33 relative dielectric constant A area of electrodes surface and d distance between electrodes Every change in the charge or displacement needs a current i 35 _dQ _ dU dt dt Where i is current U is voltage C capacitance and Q charge For static operation only leakage current has to be supplied The high internal resistance limits leakage current to low micro or submicro amp ranges 5 4 3 Temperature Effects Thermal stability of the PZT ceramics is better than most other materials It is characterized by the coefficient of thermal expansion these coefficients are dependent on the temperature PZTs work inside a range of temperatures Even down to 0 degree Kelvin However the magnitude of piezo gain is dependent on the temperature Near room temperature it is very stable 5 5 Our Plant The Block diagram in Figure 5 1 shows our plants components Our plant consists of a like structure with 1 inch square in center and four squares one on each of four sides The target to measure the movement is mounted in the center of the structure The structure is mounted on a base such desig
74. t number of execution may have varied We were able to achieve an average data exchange rate of 15 K during exper iments which did not require the data to be displayed on the screen until all analysis was completely carried out The displaying specially of the graphs and charts is a very time consuming process and thus the real time display applications like Range measurement and PI control have significantly slower data exchange rates However the exact data exchange rate cannot be ascertained for these applications since it varies very drastically as Windows 95 allocates time of execution for each program The data flow in our systems is shown as a block diagram in Figure 7 1 All lines indicate the bidirectional flow of data Each exchange of data is carried out in a certain amount of time The data on the Front panel is transferred to the memory 58 X axis without Dither X axis with small Dither 15 5 Displacement eo Displacement 10 3 2 1 0 1 2 3 Voitage Voltage X axis with medium Dither X axis with large Dither 15 10 E j amp a E 9 0 a oO Voltage Voltage Figure 7 2 Dithering in the X axis of Plant location of the data in Block diagram then block diagrams data is exchanged with CIN in the form of pointers and handles and the data exchange between the DSP and CIN is actual I O just like it is in case of the DSP and the plant 7 1 Dithering It is well known that the PZT voltage displacement r
75. the Resonance Frequency Ls 49 6 5 The Front Panel of the Proportional Integral program 93 7 1 The Block diagram of data flow llle 57 1 2 Di thering in the X axis of Plantu ues as e RA dae el 58 too Dithermguan the Y axis of Plabl osos va oer boa o earned weed 59 7 4 The PI control system completely programmed in LabVIEW 61 7 5 Block Diagram of PI control system completely programmed in LabVIEW 61 7 6 The Two PI control systetH 02s basses po A IR eR m des a Ble ERAS 62 7 7 The output from PZT as a circle tac cna E Se woe oe eae 63 A 1 The Block diagram of the case true DSP Block 65 A 2 The Block diagram of the case false DSP Block 65 Figure Page A 3 The Block diagram of the case true Hysteresis 0 66 A 4 The Block diagram of the case false Hysteresis lll 66 A 5 The Block diagram of the case true range of displacement 67 A 6 The Block diagram of the case false range of displacement 67 A 7 The Block diagram of the case true Resonance Frequency 68 A 8 The Block diagram of the case false Resonance Frequency 68 A 9 The Second Block diagram of the case true Resonance Frequency 69 A 10 The Block diagram of the case true Proportional Integral Control 69 A 11 The Block diagram of the case false Proportional Integral Control 70 xi CHAPTER 1 INTRODUCTION 1 1 Objective
76. to the outside world reads a value which is displayed on the chart it also calculates controls the plant with PI algorithm include extcode h include lt stdio h gt include lt math h gt include lt conio h gt CIN MgErr CINRun int32 Sampling_Rate int32 Reference int32 KI int32 KP int32 Bias int32 in float64 Yn float64 Un CIN MgErr CINRun int32 Sampling_Rate int32 Reference int32 KI int32 KP int32 Bias int32 in float64 Yn float64 Un ENTER YOUR CODE HERE All variables used in this function are declared Zf I I tiii 2i i i2i2i tit i it tip int sign u16 bit ul2_bit yi6_bit y12_bit int PAGE_VALUE 0x0 ADDRESSI 0x1388 ADDRESSO 0x1389 Timer_Address 0x01387 int check Check_Address 0x1386 Reference_Address 0x138d int Kl_address 0x138c KP_address 0x138b Bias_address 0x138a Start the DSP program execution SSS SSS SSS SSS SSS SSS SS SS SS SS ST SSS SS if in lt 2 8 2 86 inp 0x306 Check if the DSP is done IZLZZZZLZZEIXILEIIEIEmEmmmImmE while check 1 1 The logic to set the Reference NIIZILZILILIEXILIIILIE IEIIEmmmImEITmL outp 0x306 PAGE VALUE outpw 0x302 Reference Address outpw 0x300 Reference The logic to set the sampling rate ttti tittie EEEE outp 0x306 PAGE VALUE outpw 0x302 Timer Address outpw 0x300 50000000 Sampling Rate The logic to set the KI mEIZIIZXIZILZ
77. tten the other DAC output will be trashed Clearly this would be unacceptable and this is overcome by storing the previously output values So actually the function WrzteD AC always updates both the DACs and effectively makes it appear as if only one DAC is updated every time The value for the DAC channel 1 must be put into the upper 16 bits i e right justified in the upper 16 bit word This shifting is done and then the values for the two channels are O R ed together and then output via the serial port Obviously if 27 both the converters are to be updated then it is more efficient to do so in one call and for this another function call WriteDAC S is available This function call updates both the DAC channels in one call The prototype for this function is int WriteDACS int valueO int value1 The channels 0 and 1 are updated with the values valuel and value2 This is more efficient if both the converters are to be updated For instance in our work the controller writes both the servo commands by calling this function two calls to WriteDAC are not used 4 6 ADC Usage To input analog values from the ADC the function ReadAdc is called The prototype for this function is int ReadAdc int channel This reads the value from the ADC for the voltage applied on the specified channel The function returns values ranging from 2048 to 2047 for voltages ranging from 5V to 5V The integer data type int on the C31 DS
78. uctions from Windows 95 The systems functionality is decomposed between LabVIEW CIN and DSP The DSP mainly interfaces to the physical plant through DACs and ADCs it collects and performs some data manipulations and stores the data in the memory locations The CIN accesses these memory locations directly using the C language commands outp outpw inp and inpw which write or read data from the ports as specified in these commands The format for these commands is outp Address Value variable inp Address The output commands writes the data of the variable in position Value at the address in the Address position The input commands need a variable in which the read value from the Address is to be stored LabVIEW exchanges tne data with the CIN by references and as handles and then processes and displays the data after further analysis or manipulation Windows 95 is not a realtime operating system and thus applications running on this operating system cannot be real time The Windows 95 allocates time slots to each function active at a particular instant of time The next time slot can be awarded at any instant without relationship to the applications previous time slot Meaning that the same routine might run for a few milliseconds in one second or not at all during a whole second Depending on the priorities decided by Windows 95 operating system 2 4 1 An Example of Our GUI As an example let us discuss the development of one of ou
79. values read by DSP are passed back by the CIN to the Block diagram in the form of arrays These arrays are joined to form a cluster of data to be passed on to the Graph as well as passed on to the Spreadsheet file saving VI It is important to note that these wires are color coded by LabVIEW to express the type of the data flow in these wires i Hysterises vi Diagram Figure 3 3 The Block diagram of the case false Hysteresis The diagram should be read left to right The junction of two or more wires executes when all data required is available to the input of the junction Example is the multiplication symbol executes only when both multiplicants are available at its input terminal The graphic symbols for the different indicators and controls also show the type of data in abbreviation e g 132 for 32 bit integer and DBL for double precision floating point variables etc The Block Diagram screen of LabVIEW also gives the user some additional debugging tools like the single step show each execution and complete the execution button on the top control panel of the screen The run continuous run stop and pause buttons are also available to the user This allows us to check the data flow and the execution sequence of our block diagram for troubleshooting purposes 16 3 6 The CIN for Our Example LabVIEW provides us with a header file extcode h that contains typedefs associating LabVIEWs own unambiguous data types like int 6 for 16
80. y manip ulation to the CIN however the Frequency Voltage and Bias levels are scaled by a multiplying factor of 100 before being passed to the CIN The CIN consists of 47 four integer input output terminals and three floating point output terminals The data coming from the CIN is already scaled and is displayed as it is on the charts and in the range data display This whole block is in a case true selection of the download execute button Incase of the case false input from the download execute button the block diagram shown in the Figure A 6 in appendix A is executed This calls the batch file range bat which compiles and downloads the DSP program to interface with the LabVIEW Range VI 6 3 3 The CIN The CIN puts the DSP in execute mode and then writes the desired frequency sampling rate voltage and bias level to the DSP then when the DSP gives the check flag the new values for both input and output charts are read and the range as determined by our algorithm in the DSP is also read after which the check flag is reset It is imperative to notice once again that this experiment is supposed to run at slower speeds 6 3 4 The DSP Program The JSP program accepts tne samp ing rate at acaress 0x07387 frequency at adcress 0x0138b bias at address 0x0138c voltage at address 0x0138d and gives the range at address 0x0138a input to the plant at address 0x01388 and output from the plant at address 0x01389 The desired sampling rate
81. y of certain crystals like Quartz Rochell salt barium titanate and many others that when subjected to pressure these crystals exhibit charges on their surfaces The charges are proportional to the pressure and appear only when pressure is present Conversely when electric potential is applied to these materials the dimensions of these crystals change These materials are also called smart materials These crystals are being considered as actuators in micropositioning appli cations and precision control systems 5 1 PZT Ceramics Manufacturing Process The manufacturing process of PZT starts with mixing and milling of raw materials The milled mixture is then heated to 7596 of the sintering temperature The polycrys tallaine calcinated powder is ball milled once again Granulation with binder is carried out to improve processing properties After shaping and pressing the ceramics is heated to 750 to burn out the binder The next phase is sintering at temperatures as high as 1250 C to 1350 C The ceramic block is then finished into the desired shape and tolerance All processes especially the sintering and heating need to be controlled to very tight tolerances The smallest change effects the properties and quality of the PZT The direction of polarization is established during the poling process by a strong electrical field applied between two electrodes For actuator applications the piezo properties along the poling axis are most essent
82. ystem back and forth Some systems can be looped repeatedly and exhibit same or very slightly modified hysteresis others may not allow us to repeat the experiment We can pulsate the PZT as much as we like with care of not doing it too fast but we cannot bend and return the fork Another important factor is the speed of the repetitions if this is done very quickly the system may not exhibit its true dynamics If it is done too slowly then the drifting of the system as is the case with PZT may play a role 6 2 1 The Front Panel The front panel of the DSP block is displayed in Figure 6 2 and consists of six components ystenses vi Figure 6 2 The Front Panel of the Hysteresis program Control input for sampling rate Control input for Voltage level to be used during the experiment Binary control button for operation during the run execution The XY graph display for plotting the hysteresis loop The data display for the DSP input The data display for the DSP output We can give integer values to the control input for the sampling rate this value is written to the CIN The control for Voltage level accepts floating point values for the data or the voltage level which is to be sent to the DSP the value is in volts and has the precision of two decimal places the display is also configured to display only upto two decimal places The binary button select whether we want t

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