National Instruments 320571-01 User Manual

™

NI-DSP

Software Reference Manual

for LabVIEW

Digital Signal Processing Software for the PC

December 1993 Edition

Part Number 320571-01

for Windows

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About This Manual.................................................................................................................... xi

Assumption of Previous Knowledge ........................................................................................................ xi

Organization of This Manual.................................................................................................................... xi

Conventions Used in This Manual............................................................................................................ xii

Related Documentation ............................................................................................................................ xiv

Additional Software.................................................................................................................................. xiv

NI-DAQ for DOS/Windows/LabWindows ................................................................................ xiv

Developer Toolkit ...................................................................................................................... xv

Compatible Hardware............................................................................................................................... xv

Customer Communication ........................................................................................................................ xv

Part 1 Getting Started with NI-DSP

Product Overview ..................................................................................................................................... 1-1

The NI-DSP Software............................................................................................................................... 1-1

What Your Distribution Diskettes Should Contain.................................................................... 1-2

Installing NI-DSP for LabVIEW for Windows ........................................................................................ 1-2

Board Configuration ................................................................................................................................. 1-3

Installation on an ISA (or AT) Bus Computer ........................................................................... 1-3

Installation on an EISA Bus Computer ...................................................................................... 1-3

........................................................................................ 1-1

Part 2 Introduction to the NI-DSP Analysis VIs

Using the NI-DSP VIs in LabVIEW ........................................................................................................ 1-1

AT-DSP2200 Software Overview ............................................................................................................ 1-1

Memory Management and Data Transfer................................................................................................. 1-2

Special Features of the NI-DSP Analysis VIs .......................................................................................... 1-5

Hints for Improving the Execution Speed on the DSP Board.................................................... 1-7

An Example of Using NI-DSP Analysis VIs............................................................................................ 1-8

Part 3 NI-DSP Function Reference

Chapter 1 NI-DSP Analysis VI Reference Overview

The NI-DSP Analysis VI Overview ......................................................................................................... 1-1

Analysis VI Organization ......................................................................................................................... 1-3

Accessing the NI-DSP Analysis VIs ........................................................................................................ 1-3

About the Fast Fourier Transform (FFT).................................................................................................. 1-4

About Filtering.......................................................................................................................................... 1-5

About Windowing .................................................................................................................................... 1-6

............................................................................... 1-1

.................................................... 1-1

Chapter 2 NI-DSP Analysis VI Reference

Copy Mem(DSP to DSP).......................................................................................................................... 2-1

Copy Mem(DSP to LV)............................................................................................................................ 2-2

Copy Mem(LV to DSP)............................................................................................................................ 2-3

........................................................................................................ 2-1

Contents

DSP Absolute............................................................................................................................................ 2-4

DSP Add ................................................................................................................................................... 2-5

DSP Allocate Memory.............................................................................................................................. 2-6

DSP Blackman Window........................................................................................................................... 2-7

DSP Blackman Harris Window ................................................................................................................ 2-8

DSP Butterworth Coefficients .................................................................................................................. 2-9

DSP Chebyshev Coefficients.................................................................................................................... 2-10

DSP Clip ................................................................................................................................................... 2-11

DSP Complex FFT.................................................................................................................................... 2-12

DSP Convolution ...................................................................................................................................... 2-13

DSP Correlation........................................................................................................................................ 2-14

DSP Cross Power...................................................................................................................................... 2-15

DSP Custom.............................................................................................................................................. 2-16

DSP Decimate........................................................................................................................................... 2-17

DSP Deconvolution .................................................................................................................................. 2-18

DSP Derivative ......................................................................................................................................... 2-19

DSP Divide ............................................................................................................................................... 2-20

DSP Elliptic Coefficients.......................................................................................................................... 2-21

DSP Equi-Ripple Bandpass ...................................................................................................................... 2-23

DSP Equi-Ripple Bandstop ...................................................................................................................... 2-25

DSP Equi-Ripple HighPass ...................................................................................................................... 2-27

DSP Equi-Ripple LowPass....................................................................................................................... 2-29

DSP Exact Blackman Window................................................................................................................. 2-30

DSP Exponential Window ........................................................................................................................ 2-31

DSP FHT .................................................................................................................................................. 2-32

DSP Flat Top Window.............................................................................................................................. 2-33

DSP Force Window .................................................................................................................................. 2-34

DSP Free Memory .................................................................................................................................... 2-34

DSP Gaussian White Noise ...................................................................................................................... 2-35

DSP General Cosine Window .................................................................................................................. 2-36

DSP Hamming Window ........................................................................................................................... 2-37

DSP Handle to Address ............................................................................................................................ 2-38

DSP Hanning Window.............................................................................................................................. 2-39

DSP IIR Filter........................................................................................................................................... 2-40

DSP Impulse Pattern................................................................................................................................. 2-42

DSP Impulse Train Pattern ....................................................................................................................... 2-43

DSP Index Memory .................................................................................................................................. 2-44

DSP Init Memory...................................................................................................................................... 2-45

DSP Integral.............................................................................................................................................. 2-46

DSP Inv Chebyshev Coeff........................................................................................................................ 2-47

DSP Inverse FFT ...................................................................................................................................... 2-48

DSP Inverse FHT...................................................................................................................................... 2-49

DSP Kaiser-Bessel Window..................................................................................................................... 2-50

DSP Linear Evaluation ............................................................................................................................. 2-51

DSP Load.................................................................................................................................................. 2-51

DSP Log.................................................................................................................................................... 2-52

DSP Max & Min....................................................................................................................................... 2-53

DSP Median Filter .................................................................................................................................... 2-54

DSP Multiply ............................................................................................................................................ 2-55

DSP Parks-McClellan............................................................................................................................... 2-56

DSP Polar to Rectangular ......................................................................................................................... 2-59

DSP Polynomial Evaluation ..................................................................................................................... 2-60

DSP Power Spectrum................................................................................................................................ 2-61

DSP Product.............................................................................................................................................. 2-61

DSP Pulse Pattern..................................................................................................................................... 2-62

DSP Ramp Pattern .................................................................................................................................... 2-63

DSP Random Pattern ................................................................................................................................ 2-64

DSP Rectangular to Polar ......................................................................................................................... 2-65

NI-DSP SRM for LabVIEW for Windows vi © National Instruments Corporation

Contents

DSP ReFFT............................................................................................................................................... 2-66

DSP Reset ................................................................................................................................................. 2-66

DSP Reverse ............................................................................................................................................. 2-67

DSP Sawtooth Pattern............................................................................................................................... 2-68

DSP Set..................................................................................................................................................... 2-69

DSP Shift .................................................................................................................................................. 2-69

DSP Sinc Pattern....................................................................................................................................... 2-70

DSP Sine Pattern....................................................................................................................................... 2-71

DSP Square Pattern................................................................................................................................... 2-72

DSP Square Root ...................................................................................................................................... 2-73

DSP Sort ................................................................................................................................................... 2-74

DSP Start .................................................................................................................................................. 2-75

DSP Subset ............................................................................................................................................... 2-75

DSP Subtract............................................................................................................................................. 2-76

DSP Sum................................................................................................................................................... 2-76

DSP TimeOut............................................................................................................................................ 2-77

DSP Triangle Pattern ................................................................................................................................ 2-78

DSP Triangular Train................................................................................................................................ 2-80

DSP Triangular Window .......................................................................................................................... 2-81

DSP Uniform White Noise ....................................................................................................................... 2-82

DSP Unwrap Phase................................................................................................................................... 2-83

DSP Zero Padder ...................................................................................................................................... 2-84

Part 4 NI-DSP Interface Utilities

Chapter 1 Introduction to the NI-DSP Interface Utilities

Overview of the NI-DSP Interface Utilities.............................................................................................. 1-1

Installing the NI-DSP Interface Utilities .................................................................................................. 1-2

Using the NI-DSP Interface Utilities ........................................................................................................ 1-2

Chapter 2 Getting Started with the NI-DSP Interface Utilities

Creating Your Custom NI-DSP Library................................................................................................... 2-1

1. Create Your Source Code of C Functions............................................................................. 2-1

GMaxMin.c Example.................................................................................................. 2-1

Guidelines for the Custom Functions .......................................................................... 2-2

DSP Board Memory Management............................................................................... 2-3

2. Compile and/or Assemble Source Code................................................................................ 2-4

3. Add Your Object Filenames to a Linker File (ifile).............................................................. 2-4

4. Add Your New Function Names to a Library Function List File.......................................... 2-4

Customizing the DSP Library by Deleting Functions ................................................. 2-5

5. Run the Build Dispatch Application to Generate an Assembly Dispatch File...................... 2-6

6. Compile, Assemble, and Link Your Custom Library............................................................ 2-7

Creating Your LabVIEW Interface .......................................................................................................... 2-8

1. Bundle All of the Input Parameters to Arrays....................................................................... 2-8

2. Call the Custom VI................................................................................................................ 2-10

3. Index the Output Arrays to Obtain the Results ..................................................................... 2-10

Executing the Custom Function from LabVIEW ..................................................................................... 2-12

.................................................................... 1-1

....................................................... 2-1

Chapter 3 DSP Board Function Overview

Data Acquisition Functions ...................................................................................................................... 3-3

...................................................................................................... 3-1

Contents

Chapter 4 Using the DMA VIs

DSP DMA Copy(DSP to LV)................................................................................................................... 4-3

DSP DMA Copy(LV to DSP)................................................................................................................... 4-4

Appendix A

.................................................................................................................................. 4-1

Error Codes

Error Conditions........................................................................................................................................ A-1

.......................................................................................................................................... A-1

Appendix B Customer Communication

............................................................................................... B-1

Glossary........................................................................................................................................... Glossary-1

Index.......................................................................................................................................................... Index-1

NI-DSP SRM for LabVIEW for Windows viii © National Instruments Corporation

Contents

Figures

Part 1

Figure 1-1. Development Paths with the NI-DSP Software............................................................................. 1-1

Part 2

Figure 1-1. Communication between the PC and the DSP Board .................................................................... 1-1

Figure 1-2. DSP Handle Cluster ....................................................................................................................... 1-3

Figure 1-3. The Hexadecimal Encoding of a Typical DSP Handle.................................................................. 1-3

Figure 1-4. Front Panel–An Example of How to Allocate a DSP Handle Cluster........................................... 1-4

Figure 1-5. Block Diagram–An Example of How to Allocate a DSP Handle Cluster..................................... 1-4

Figure 1-6. DSP Add VI ................................................................................................................................... 1-5

Figure 1-7. The error in/error out Cluster...................................................................................................... 1-5

Figure 1-8. An Example That Does Not Use error in/error out for Sequencing VIs .................................... 1-6

Figure 1-9. An Example of Using the error in/error out Cluster for Sequential VI Execution..................... 1-7

Figure 1-10. Front Panel–An Example of Using NI-DSP Analysis VIs ............................................................ 1-8

Figure 1-11. Block Diagram–An Example of Using NI-DSP Analysis VIs ...................................................... 1-8

Part 3

Figure 1-1. Choosing DSP2200 from the Functions Menu .............................................................................. 1-4

Figure 1-2. Spectral Leakage Demonstrated Using Convolution..................................................................... 1-7

Part 4

Figure 1-1. NI-DSP for DOS Directory Structure ............................................................................................ 1-1

Figure 1-2. Interface Layers to Onboard Functions.......................................................................................... 1-2

Figure 2-1. Linker File NIDSPLNK................................................................................................................. 2-4

Figure 2-2. Library Function List File NIDSP.fnc ........................................................................................... 2-4

Figure 2-3. Typical Section of NIDSP.fnc ....................................................................................................... 2-5

Figure 2-4. Signals Group Section in dspfncs.h ............................................................................................... 2-6

Figure 2-5. Signals Group Section in dispatch.s............................................................................................... 2-6

Figure 2-6. How to Bundle Parameters in LabVIEW to Call gmaxmin.c ........................................................ 2-9

Figure 2-7. How to Connect to Custom VI to Call gmaxmin.c........................................................................ 2-10

Figure 2-8. Block Diagram–How to Index the Output Arrays of the Custom VI ............................................ 2-11

Figure 2-9. Block Diagram–Using the Custom VI to Call gmaxmin.c on theDSP Board from LabVIEW..... 2-11

Figure 2-10. Front Panel–Using the Custom VI to Call gmaxmin.c on theDSP Board from LabVIEW........... 2-12

Contents

Tables

Part 1

Table 1-1. Subdirectories Created by SETUP................................................................................................. 1-2

Part 3

Table 1-1. The NI-DSP Analysis VI Groups .................................................................................................. 1-1

Part 4

Table 2-1. Files Required to Build the Custom DSP Library Example .......................................................... 2-7

Appendix A

Table A-1. NI-DSP Analysis Library Error Codes .......................................................................................... A-1

NI-DSP SRM for LabVIEW for Windows x © National Instruments Corporation

About This Manual

The NI-DSP Software Reference Manual for LabVIEW for Windows explains how to use the NI-DSP software package for the LabVIEW for Windows environment. The NI-DSP software package contains the NI-DSP Analysis VIs, which are high-level digital signal processing (DSP) VIs that call the functions that execute on the AT-DSP2200 plug-in board for IBM AT bus and compatible computers. This manual describes how to use the NI-DSP Analysis VIs to develop applications in LabVIEW using the AT-DSP2200 board.

The NI-DSP software package also contains the NI-DSP Interface Utilities. The NI-DSP Interface Utilities are a set of tools and examples that help you customize your NI-DSP Analysis VIs and the DSP Library, which is resident on the board. This manual contains step-by-step instructions and useful examples to help the LabVIEW developer add custom algorithms to the NI-DSP Analysis VIs using the NI-DSP Interface Utilities.

Assumption of Previous Knowledge

The material in this manual is for users who are familiar with LabVIEW and the IBM family of computers and compatible computers.

Organization of This Manual

This manual is divided into four parts.

• Part 1, Getting Started with NI-DSP, contains a brief product overview, information about the NI-DSP for LabVIEW for Windows package, and the procedure for installing the software.

• Part 2, Introduction to the NI-DSP Analysis VIs, describes how to use the NI-DSP Analysis VIs in your LabVIEW applications. This part also describes how to manage memory on the DSP board from your LabVIEW application, and how to transfer data between your LabVIEW application and the NI-DSP functions on the board. This part contains general guidelines for developing NI-DSP applications within LabVIEW.

• Part 3, NI-DSP Function Reference, is intended as a reference for users familiar with Part 2. Part 3 is organized as follows:

- Chapter 1, NI-DSP Analysis VI Reference Overview, contains an overview of the NI-DSP Analysis VIs and

includes a list of the VIs. This chapter describes how the NI-DSP Analysis VIs are organized, and how to access them.

- Chapter 2, NI-DSP Analysis VI Reference, contains a brief explanation of each NI-DSP Analysis VI. The

VIs are arranged alphabetically.

• Part 4, NI-DSP Interface Utilities, explains how to customize the NI-DSP Analysis Library on the board and to create and run interfaces in LabVIEW to your custom library functions. Part 4 is organized as follows:

- Chapter 1, Introduction to the NI-DSP Interface Utilities, contains an overview of the NI-DSP Interface

Utilities, installation instructions, and explains how to use the NI-DSP Interface Utilities.

- Chapter 2, Getting Started with the NI-DSP Interface Utilities, contains a step-by-step example for building

a custom DSP Library, creating a LabVIEW interface to a custom function, and executing the custom function from the LabVIEW environment. The chapter demonstrates this concept with an example of how to add a custom function.

About This Manual

- Chapter 3, DSP Board Function Overview, contains an overview of the prototypes of the C-callable

NI-DSP Analysis functions on the DSP board that you can use in your custom programs.

- Chapter 4, Using the DMA VIs, describes two special VIs that transfer data between the host computer and

the DSP board without interfering with the DSP board.

• Appendix A, Error Codes, contains a list of the error codes returned by the NI-DSP Analysis VIs and the corresponding error messages.

• Appendix B, Customer Communication, contains forms you can use to request help from National Instruments or to comment on our products and manuals.

• The Glossary contains an alphabetical list and description of terms used in this manual, including abbreviations, acronyms, metric prefixes, mnemonics, and symbols.

• The Index alphabetically lists topics covered in this manual, including the page where the topic can be found.

Conventions Used in This Manual

The following conventions are used in this manual: <> Angle brackets enclose the name of a key on the keyboard–for example, <enter>. bold Bold text denotes menus, command names, parameters, function panel items, error

messages, and warnings. DSP board DSP board refers to the AT-DSP2200. DSP Handle DSP Handle refers to a 32-bit long integer code that constitutes an indirect reference to a

buffer of memory in the memory space of an AT-DSP2200 board. The code contains

information about the slot number of the board on which that buffer is allocated. DSP Handle Cluster DSP Handle Cluster refers to a cluster that constitutes two fields–a DSP Handle and a

32-bit size that indicates the number of elements the DSP Handle holds. DSP Library DSP Library refers to a common object file format (COFF) that constitutes NI-DSP

software that resides and runs on the AT-DSP2200 board. The DSP Library consists of

the Kernel, memory management routines, execution control routines, data

communication routines, interrupt handling routines, data acquisition routines and a set of

analysis functions. <enter> Key names are in lowercase letters. Interface Library Interface Library refers to the part of the NI-DSP software that resides on the PC and is

linked with your application in order to communicate data to and from the DSP board.

The Interface Library communicates with the DSP board using the driver. italic Italic text denotes emphasis, a cross reference, or an introduction to a key concept.

italic monospace

Italic text in this font denotes that you must supply the appropriate words or values in the

place of these items.

NI-DSP SRM for LabVIEW for Windows xii © National Instruments Corporation

About This Manual

LabVIEW Data Types Each VI description includes a data type picture for each control and indicator, as

illustrated in the following table:

Control Indicator Data Type

Boolean String Signed 16-bit integer

Array of signed 16-bit integers Signed 32-bit integer Array of signed 32-bit integers 32-bit floating-point number; by default,

floating-point numbers are double precision Array of 32-bit floating-point numbers

Path DSP Handle Cluster

Array of DSP Handle Clusters

Error Cluster

monospace Text in this font denotes text or characters that are to be literally input from the keyboard,

sections of code, programming examples, and syntax examples. This font is also used for

the proper names of disk drives, paths, directories, programs, subprograms, subroutines,

device names, array names, structures, variables, filenames, and extensions, and for

statements and comments taken from program code. NI-DAQ NI-DAQ is used throughout this manual to refer to the NI-DAQ software for

DOS/Windows/LabWindows unless otherwise noted. NI-DSP NI-DSP is used throughout this manual to refer to the NI-DSP software for LabVIEW for

Windows unless otherwise noted. PC PC refers to the IBM PC AT and compatible computers, and to EISA personal computers. WE DSP32C tools WE DSP32C tools is used throughout this manual to refer to the AT&T WE DSP32C

Developer Toolkit. Abbreviations, acronyms, metric prefixes, mnemonics, symbols, and terms are listed in the Glossary.

About This Manual

Additional Software

Additional DSP board software includes NI-DAQ for DOS/Windows/LabWindows and the Developer Toolkit.

NI-DAQ for DOS/Windows/LabWindows

Your AT-DSP2200 is shipped with the NI-DAQ for DOS/Windows/LabWindows software. NI-DAQ has a library of functions that can be called from your application programming environment. These functions include routines for analog input (A/D conversion), buffered data acquisition (high-speed A/D conversion), analog output (D/A conversion), waveform generation, digital I/O, counter/timer, SCXI, RTSI, and self-calibration. NI-DAQ maintains a consistent software interface among its different versions so you can switch between platforms with minimal modifications to your code. NI-DAQ comes with language interfaces for Professional BASIC, Turbo Pascal, Turbo C, Turbo C++, Borland C++, Microsoft C for DOS; and Visual Basic, Pascal, Microsoft C with SDK, and Borland C++ for Windows. NI-DAQ for DOS/Windows/LabWindows software is on high-density 5.25 in. and

3.5 in. diskettes. You can use the DSP board in conjunction with the National Instruments AT Series data acquisition boards and software to create a complete solution for integrated data acquisition and data analysis applications.

NI-DSP SRM for LabVIEW for Windows xiv © National Instruments Corporation

About This Manual

Developer Toolkit

The Developer Toolkit, an optional software package that you can purchase separately from National Instruments, is required for building custom libraries with the NI-DSP Interface Utilities. The Developer Toolkit contains an AT&T C compiler, assembler, linker, and documentation. With these tools, you can program AT Series DSP boards directly, using theboard flexibility to custom tailor the DSP Library. The C compiler optimizes WE DSP32C code and generates assembly language code that can be assembled and linked into a run-time module. When a run-time module is completed, use the download tools and the debugger to load, debug, and execute the code, set parameters, and report results. The Developer Toolkit also includes the WE DSP32C Support Software Library User Manual and the WE DSP32 and WE DSP32C Language Compiler Library Reference Manual.

Compatible Hardware

You can use DSP boards in conjunction with the National Instruments AT Series data acquisition boards. In particular, the National Instruments AT-DSP2200 is a high-performance, DSP board with high-accuracy audio frequency (DC to 51.2 kHz) analog input/output for the PC. The AT-DSP2200 gives the PC a dedicated high-speed numerical computation engine that can perform scientific calculations faster than the general-purpose 80x86 microprocessor on the PC.

Customer Communication

National Instruments wants to receive your comments on our products and manuals. We are interested in the applications you develop with our products, and we want to help if you have problems with them. To make it easy for you to contact us, this manual contains comment and configuration forms for you to complete. These forms are in Appendix B, Customer Communication, at the end of this manual.

Part 1 Getting Started with NI-DSP

This part contains a brief product overview, information about the NI-DSP for LabVIEW for Windows package, and the procedure for installing the software.

Product Overview

The NI-DSP software package comes with a set of LabVIEW VIs that invoke the digital signal processing (DSP) board-resident high-performance functions that efficiently process large blocks of numerical data and perform numerically intensive computations. The NI-DSP Analysis VIs include numerical analysis, signal generation, DSP, windowing, digital filtering, and memory management that are suitable for simulation, modeling, and sophisticated data processing.

You can use NI-DSP to develop programs in the LabVIEW for Windows environment. This software comes with the NI-DSP Interface Utilities so you can customize the DSP Library by adding functions to or deleting functions from the Analysis Library on the DSP board and/or add interfaces to these custom functions in LabVIEW.

Figure 1-1 shows the development path for NI-DSP in the LabVIEW environment.

NI-DSP for

The LabVIEW

for Windows

Development

Environment

AT&T

Development

Environment

and T ools

(Optional)

Figure 1-1. Development Paths with the NI-DSP Software

LabVIEW

for Windows

Interface

Utilities

The NI-DSP Software

The NI-DSP software consists of the NI-DSP for LabVIEW for Windows diskettes.

User

Application

The NI-DSP software contains a Warranty Registration Form. Please fill out this form and return it to National Instruments. The Warranty Registration Form entitles you to receive product upgrades and technical support.

NI-DSP SRM for LabVIEW for Windows 1-1 Part 1: Getting Started with NI-DSP

Getting Started with NI-DSP Part 1

What Your Distribution Diskettes Should Contain

The NI-DSP software package contains the NI-DSP for LabVIEW for Windows Disks (for licensed LabVIEW for Windows users). If your kit is missing any of these components, contact National Instruments.

Installing NI-DSP for LabVIEW for Windows

Note: NI-DSP for LabVIEW for Windows is intended for use with the standard LabVIEW for Windows software.

You must install LabVIEW for Windows before installing NI-DSP. You must install the Data Acquisition Library of LabVIEW to run the NI-DSP software.

Before beginning the software installation, make backup copies of the NI-DSP for LabVIEW for Windows distribution disks. Copy each disk onto a correctly labeled backup disk and store the original distribution disks in a safe place.

You can install NI-DSP for LabVIEW for Windows from the DOS prompt, the Windows File Manager, or with the Run... command from the File menu of the Program Manager.

1. Insert Disk 1 into the disk drive and run the SETUP.EXE program on Disk 1 using one of the following three

methods.

• From the DOS prompt, type X: \SETUP (where X is the proper drive designation).

• From Windows, select Run... from the File menu of the Program Manager. A dialog box appears. Type

X: \SETUP (where X is the proper drive designation).

• From Windows, launch the File Manager. Click on the drive icon that contains Disk 1. Find SETUP.EXE in the list of files on that disk and double-click on it.

2. The installer gives you the option of performing a full installation or a custom installation. Unless you do not have sufficient disk space (approximately 4 megabytes), National Instruments recommends that you perform a full installation. After you choose an installation, follow the instructions that appear on the screen.

After calling SETUP, the appropriate directories are created and the needed files are copied to your hard drive. SETUP can also install the NI-DSP Interface Utilities, discussed in Part 4, NI-DSP Interface Utilities, of this manual. If you choose Full Installation, SETUP does the following things:

1. SETUP creates a subdirectory called DSP2200 of the vi.lib subdirectory of the LabVIEW directory. SETUP decompresses the NI-DSP Analysis VIs (as LabVIEW .LLB files) in the DSP2200 directory.

2. SETUP copies DSP.DLL to your windows directory.

3. SETUP creates the subdirectories shown in Table 1-1 under the directory you specified during setup. These subdirectories make up the NI-DSP Interface Utilities.

4. SETUP creates a subdirectory called DSP2200 of the EXAMPLES subdirectory of the LabVIEW directory. SETUP copies all of the NI-DSP VI examples there.

Table 1-1. Subdirectories Created by SETUP

Subdirectory Name Description

C:\NIDSP\LIB Library files for linking with stand-alone programs C:\NIDSP\DISPATCH The Dispatch utility and related files C:\NIDSP\EXAMPLES Contains source code for the examples

Part 1: Getting Started with NI-DSP 1-2 NI-DSP SRM for LabVIEW for Windows

Part 1 Getting Started with NI-DSP

NIDSP is the name you specify during setup. The SETUP program prompts you for information including the drive letter and directory in which you have

installed the standard LabVIEW package. The program also verifies that your hard disk has enough space to hold the NI-DSP for LabVIEW for Windows files.

If you choose Custom Installation, SETUP installs only the files you specify.

Board Configuration

There are several board configuration parameters that must be established before an NI-DSP application can execute properly. These parameters are the board ID number, the board subtype, the base address, the interrupt level, the DMA channel, and the pathname of the DSP Library files. These parameters are established differently depending on whether you are installing the AT-DSP2200 in an ISA (or AT) bus computer or an EISA bus computer.

Installation on an ISA (or AT) Bus Computer

A configuration utility is supplied with the LabVIEW data acquisition software for establishing all the configuration parameters on ISA bus computers. This utility, called WDAQCONF.EXE, saves the configuration parameters in a file named WDAQCONF.CFG. Use the WDAQCONF utility to assign a board ID number to your AT-DSP2200, to choose the memory subtype (either 64 Kwords or ≥128 Kwords), to set the base address, interrupt level, and DMA channel, and to specify the pathname of the DSP Library file.

Two DSP Library files are supplied with your NI-DSP software–LV2200S.OUT and LV2200.OUT. LV2200S.OUT is intended for use with the 64 Kword version of the AT-DSP2200. LV2200.OUT is intended for use with any other version of the board. With the WDAQCONF utility, you can enter a complete path that will include the DSP Library file name. If you enter complete pathnames, you can configure the NI-DSP software to automatically load custom versions of the DSP Library files.

If you installed the Data Acquisition Library of LabVIEW, you can find WDAQCONF.EXE of your LabVIEW directory. From Windows, you run WDAQCONF.EXE by double-clicking on its icon.

Installation on an EISA Bus Computer

Installing the AT-DSP2200 board on an EISA bus computer involves two different configuration utilities.

• A system configuration utility is supplied with your computer by your computer vendor. This utility, along with the !NIC1100.CFG EISA configuration file installed by the LabVIEW SETUP program, is used to assign a slot number to the AT-DSP2200, to choose the memory subtype (either 64 Kwords or ≥128 Kwords), and to set the base address, interrupt level, and DMA channel.

There are typically two methods for running your EISA system configuration utility.

1. Boot from the diskette containing the utility and place a copy of the !NIC1100.CFG file on this diskette.

2. Run the utility from a directory on your hard disk and place a copy of the !NIC1100.CFG file in this

directory. The EISA system configuration utility is typically named CF.EXE.

• You must use the WDAQCONF utility to enter the DSP Library file pathname. You can only do this after completing the EISA system configuration. Refer to the information concerning the establishment of this pathname in the previous section titled, Installation on an ISA (or AT) Bus Computer.

Before using NI-DSP, you must run WDAQCONF.EXE to configure your DSP board. For more information about board configuration, refer to Chapter 1, Introduction and Configuration, of the

LabVIEW Data Acquisition VI Reference Manual.

NI-DSP SRM for LabVIEW for Windows 1-3 Part 1: Getting Started with NI-DSP

Part 2 Introduction to the NI-DSP Analysis VIs

This part describes how to use the NI-DSP Analysis VIs in your LabVIEW applications. This part also describes how to manage memory on the DSP board from your LabVIEW application, and how to transfer data between your LabVIEW application and the NI-DSP functions on the board. This part contains general guidelines for developing NI-DSP applications within LabVIEW.

Using the NI-DSP VIs in LabVIEW

LabVIEW users use the NI-DSP Analysis VIs as if they were any other standard VIs, as described in the LabVIEW User Manual. Notice, however, that the NI-DSP Analysis VIs run analysis code on the DSP board rather than on the

host CPU. One of the major features includes the memory management and data transfer VIs, which are discussed in detail in the section titled Memory Management and Data Transfer later in this chapter.

AT-DSP2200 Software Overview

The AT-DSP2200 board, working in conjunction with your personal computer, is a powerful numeric processor for high-speed analysis of data arrays. The NI-DSP for LabVIEW for Windows software includes a number of utilities and low-level memory management and data transfer VIs that facilitate communication between the DSP board and the host computer. Figure 1-1 is a block diagram of the software utilities and libraries that control the AT-DSP2200. The DSP Library and the low-level memory management and data transfer functions reside and execute on the board. You can customize the DSP Library to optimize performance, as described in Part 4, Chapter 2, Getting Started with the NI-DSP Interface Utilities, of this manual. Your application programs and the Interface Library, however, reside on the host PC.

User

Application

in LabVIEW

Interface

(CIN)

PC AT-DSP2200

Interface

Library

(DSP.DLL)

Figure 1-1. Communication between the PC and the DSP Board

AT or EISA Bus

DSP Software

Onboard Kernel,

DSP Board

Memory Management, Data Transfer

Functions

DSP Library

DSP Hardware

CPU

Onboard Memory

NI-DSP SRM for LabVIEW for Windows 1-1 Part 2: Introduction to the NI-DSP Analysis VIs

Introduction to the NI-DSP Analysis VIs Part 2

The AT-DSP2200 can process large amounts of data, separately and distinctly from the host PC processor. The board consists not only of a signal processing chip, but also memory where data that the board processes must reside. The AT-DSP2200 does not have access to memory locations on the host PC. Therefore, you must download all data from your application programs to DSP board memory before processing it.

The Interface Library, DSP.DLL, and the Code Interface Node (CIN) interface, which reside on the PC, serve as a bridge between your application programs in LabVIEW and the DSP software running on the board. When you call an NI-DSP Analysis VI, the VI passes the parameters to the CIN first, which then passes the parameters to the Interface Library, DSP.DLL. The Interface Library determines what type of parameters are being passed, decides how to set up the data in DSP board memory, and then calls the actual functions that will run on the board.

When a function on the DSP board processes data, it assumes the data is resident in DSP board memory. Because transferring data between the PC and the DSP board slows down processing, none of the NI-DSP Analysis VIs transfer data back and forth internally except the data transferring VIs. The NI-DSP Analysis VIs process the data buffers that are already on the board and leave the results on the board.

If the data buffer you want to process using the DSP board is in PC memory, you must copy the data to the DSP board before you call a function on the DSP board to process the data. To see the results, you must then copy the data back to the PC. Several special NI-DSP Analysis VIs perform these transfers. For scalars, the NI-DSP Analysis VIs automatically perform the transfer for you.

The representation of data buffers in the NI-DSP Analysis VIs is not the normal LabVIEW data array representation because the data buffers indicate the data location on the DSP board instead of the PC address. A special structure, called a DSP Handle Cluster, represents the data buffer on the DSP board from LabVIEW. The DSP Handle Cluster is a coded DSP board memory address that indicates where the data buffer is on the DSP board. You must call the DSP Allocate Memory VI to obtain a valid DSP Handle Cluster. Several VIs can manage the memory on the DSP board. You can allocate and deallocate memory on the DSP board using these VIs. The next section, Memory Management and Data Transfer, discusses the VIs used to allocate memory and transfer data buffers to and from the DSP board.

Memory Management and Data Transfer

This section describes how to manage memory on the DSP board from your LabVIEW application and how to transfer data between your LabVIEW application and the DSP board.

The NI-DSP for LabVIEW package contains a set of VIs that manage memory space on the DSP board and help improve data transfers between the DSP board and your application. There are VIs for allocating memory buffers on the DSP board, for indexing into previously allocated buffers, for deallocating buffers and for copying data between DSP and LabVIEW. The following VIs, described in greater detail in Part 3 of Chapter 2, NI-DSP Analysis VI Reference, handle memory management on the DSP board and data transfers between the DSP board and your LabVIEW application:

• Copy Mem[DSP to DSP]

• Copy Mem[DSP to LV]

• Copy Mem[LV to DSP]

• DSP Allocate Memory

• DSP Free Memory

• DSP Index Memory

• DSP Init Memory

Part 2: Introduction to the NI-DSP Analysis VIs 1-2 NI-DSP SRM for LabVIEW for Windows

Part 2 Introduction to the NI-DSP Analysis VIs

The DSP Allocate Memory VI allocates memory buffers on the DSP board and returns a DSP Handle Cluster, which has two fields that uniquely describe this buffer–a DSP Handle and a size.

Figure 1-2. DSP Handle Cluster

DSP Handle is a 32-bit integer containing information that indicates the board on which the allocated buffer resides, and an index into an onboard Memory Look Up Table (MLUT) that holds the actual DSP address of the buffer that this handle represents. Figure 1-3 shows how a DSP Handle is encoded. The size field holds the number of elements in this buffer. An element can be 4 bytes (for 32-bit floating-point data or long integer data) or 2 bytes (for 16-bit integer data) depending on the bytes per element selector used in the DSP Allocate Memory VI.

X XXX 3 0 04

Figure 1-3. The Hexadecimal Encoding of a Typical DSP Handle

The first four hexadecimal numbers (upper 16 bits) of the DSP Handle, shown in Figure 1-3, are a special value. The interface code for a particular function that your application calls decodes these four hexadecimal numbers to determine if the argument is a valid DSP Handle.

Notes: Do not change the value of a DSP Handle Cluster. Keep in mind that a DSP Handle Cluster is just an entry

of a table that indicates where the data buffer is on the DSP board. If you want to operate on part of the data in that buffer, use the DSP Index Memory VI or the DSP Subset VI to obtain a new DSP Handle Cluster to hold the part of the data. Then operate on the new DSP Handle Cluster.

}

Board Number of

Special Code

Owner DSP Board

}

Index into the

MLUT of the

Owner DSP Board

The Memory Look-Up Table (MLUT) has only 128 entries. You can allocate only a total of 128 different DSP Handle Clusters. Although you might have physical memory on the DSP board, you will get an error message for not having enough memory if you already have 128 DSP Handle Clusters in use. Free the DSP Handle Clusters that are not in use. The DSP Init Memory VI will free all DSP Handle Clusters on the specified DSP board.

NI-DSP SRM for LabVIEW for Windows 1-3 Part 2: Introduction to the NI-DSP Analysis VIs

Introduction to the NI-DSP Analysis VIs Part 2

Figures 1-4 and 1-5 show how to allocate a DSP Handle Cluster of 2,048 4-byte-long elements on board 3. The board number on which the buffer is allocated is important for determining the ownership of the buffer. When making a VI call, the same DSP board on which the function is to execute must own all of the DSP Handle Clusters or an error code is returned. Only the DSP Allocate Memory VI and few other VIs that do not have DSP Handle Clusters as input parameters have a board slot parameter. VIs that have DSP Handle Clusters as input parameters obtain the board slot information from their own DSP Handle Clusters. All of the DSP Handle Clusters should have the same slot information, because the DSP VIs assume that all are executing on the same DSP board.

Figure 1-4. Front Panel–An Example of How to Allocate a DSP Handle Cluster

Figure 1-5. Block Diagram–An Example of How to Allocate a DSP Handle Cluster

For all of the NI-DSP Analysis VIs, the array data type is DSP Handle Cluster. Before you call any of these VIs, call the DSP Allocate Memory VI to obtain a valid DSP Handle Cluster, which you then use as a reference to your data buffer. The Analysis VIs assume that the data is already on the board and stores the results on the board. If you want to copy data between the PC and the DSP board, use either the Copy Mem(LV to DSP) VI or the Copy Mem(DSP to LV) VI to copy data back and forth.

If you use the DSP Allocate Memory VI in your program, use the DSP Free Memory VI to free buffers allocated when you do not need them any more. The board holds these allocations in memory even after your application has completed or you exit LabVIEW unless you execute the DSP Init Memory VI or reload the DSP Library. Thus, it is important to free all buffers your application allocated before you exit the application or you may run out of memory on the board.

Part 2: Introduction to the NI-DSP Analysis VIs 1-4 NI-DSP SRM for LabVIEW for Windows

Part 2 Introduction to the NI-DSP Analysis VIs

Special Features of the NI-DSP Analysis VIs

This section describes the special features of the NI-DSP Analysis VIs that make them different from other LabVIEW VIs.

• DSP Handle Cluster in/out. The way you specify the output data buffers for NI-DSP Analysis VIs is different

from the way you would specify output data buffers for other LabVIEW VIs. DSP Handle Clusters also represent all the output data buffers in the NI-DSP Analysis VIs. To use valid DSP Handle Clusters for the NI-DSP VI output data buffers, you must use the DSP Allocate Memory VI to obtain the DSP Handle Clusters before you use them. Supply all of the output DSP Handle Clusters as inputs to tell the DSP board where the output buffers are. Every output DSP Handle Cluster is identical to the corresponding input DSP Handle Cluster. The two DSP Handle Clusters are internally connected. The output is an indicator. The input is a control. For example, in the DSP Add VI, shown in Figure 1-6, Z is the DSP Handle Cluster that indicates where to store the results. You use Z in to connect to a valid DSP Handle Cluster that you previously allocated. Z in tells the DSP board where the results will be stored. Z out is the location where the results have already been stored. Because Z in and Z out are the same DSP Handle Cluster, you need to free only one of them when you want to deallocate their DSP board buffer.

Figure 1-6. DSP Add VI

All of the controls and indicators in the NI-DSP Analysis VIs follow the Z in, Z out naming convention and work in the same way as previously described in the example, except for the error in/error out cluster.

• Error Handling. All of the NI-DSP Analysis VIs have an error input and an error output for managing and reporting errors. The error in/error out cluster used by the NI-DSP VIs and many other high-level I/O operations is a cluster containing a Boolean indicating whether the data should be treated as an error, a 32-bit error code, and a descriptive string that usually contains the name of the source of the error. The error in/error out cluster is shown in Figure 1-7.

Figure 1-7. The error in/error out Cluster

NI-DSP SRM for LabVIEW for Windows 1-5 Part 2: Introduction to the NI-DSP Analysis VIs

Introduction to the NI-DSP Analysis VIs Part 2

The error in/error out cluster contains the following elements:

The boolean value is true if an error occurred, false if no error occurred.

code is the error code. source is the source of the error. If an error occurs during execution, the VI sets source to the name

of the VI that produced the error.

Every VI checks error in first. If there is an error, the VI does not execute any DSP code but simply passes the contents of error in to the error out cluster. If there is no error, the VI executes. One advantage of this error in/error out design is that you can connect several I/O operations together so that, if an error occurs, subsequent VIs do not perform undesired actions. DSP Free Memory will execute even if an error occurs. This ensures that allocated buffers are freed even if an error occurred.

Another advantage of this error in/error out design is that you can establish the order of a set of operations, even if there is no other data flow between the operations. Connecting the error out of the first VI to the error in of the second VI establishes data flow and therefore execution order. You could do the same thing with a Sequence structure, but with the error in/error out design, you can establish the order with all of the operations at the top level of the block diagram. For example, in Figure 1-8, you allocate DSP Handle Clusters X and Y as inputs, and you want to free X and Y after the DSP Add VI has been executed. If you simply connect X to the DSP Free Memory VI as shown in Figure 1-8, there is no sequential order between the DSP Add VI and the DSP Free Memory VI. If the DSP Free Memory VI executes first, the DSP Add VI will receive an invalid handle because that DSP Handle Cluster was deallocated.

Figure 1-8. An Example That Does Not Use error in/error out

for Sequencing VIs

If you connect the VIs as shown Figure 1-9 instead, you ensure that the DSP Add VI executes before the DSP Free Memory VI.

Part 2: Introduction to the NI-DSP Analysis VIs 1-6 NI-DSP SRM for LabVIEW for Windows

Part 2 Introduction to the NI-DSP Analysis VIs

error out of the Copy Mem(LV to DSP) VI is connected to the error in of the DSP Free Memory VI

error out of the DSP Add VI is connected to the error in of the Copy Mem(LV to DSP) VI

Figure 1-9. An Example of Using the error in/error out Cluster for Sequential VI Execution

For more information about the error in/error out cluster, refer to Chapter 2, Error Handler VIs, in the LabVIEW

Utility VI Reference Manual.

Hints for Improving the Execution Speed on the DSP Board

Check each of the following things to maximize your DSP board performance:

• Allocate as many of the DSP Handle Clusters as you can before you operate on the data. Keep all data on the DSP board until you finish all of the processing. Reduce the number of data transfers between the DSP board and the PC as much as possible. The functions that run on the DSP board are very fast, but transferring data between the DSP board and the PC and memory allocation slows the total processing performance.

• Use the error in/error out cluster for sequencing VI execution. Be sure all of your VIs run in the correct sequence. Use the error in/error out cluster to propagate the errors. If an error occurs, you can tell where the error happens. You can use the LabVIEW error handler VIs in the Utility option of the Functions menu to obtain pop-up error messages. Refer to the LabVIEW Utility VI Reference Manual for more information about these VIs.

• Many analysis routines on the DSP board can be performed in place; that is, the input and output array can be the same array. This is very important to remember when you are processing large amounts of data. Large 32-bit floating-point arrays consume a lot of memory. If the results you want do not require that you keep the original array or an intermediate array of data, perform analysis operations in place whenever possible. For example, use the same DSP Handle Cluster for the input and output data buffers in your diagram in LabVIEW. This will save your DSP board memory.

• Several intermediate-level data acquisition VIs work with DSP Handle Clusters. These VIs can acquire data and leave it on the board. You can use the NI-DSP Analysis VIs to operate on this data and then copy the processed results back to the PC. In this way, you dramatically reduce the data transfer overhead between the PC and the DSP board, and improve the overall performance. For more information about these data acquisition VIs, refer to the LabVIEW Data Acquisition VI Reference Manual. An example that shows you how to use a DSP Handle Cluster to acquire data and process this data on the DSP board can be found in the DSP2200 subdirectory of the EXAMPLES subdirectory of your LabVIEW directory.

NI-DSP SRM for LabVIEW for Windows 1-7 Part 2: Introduction to the NI-DSP Analysis VIs

Introduction to the NI-DSP Analysis VIs Part 2

An Example of Using NI-DSP Analysis VIs

Figures 1-10 and 1-11 show the front panel and block diagram, respectively, of an example using NI-DSP Analysis VIs.

Figure 1-10. Front Panel–An Example of Using NI-DSP Analysis VIs

Figure 1-11. Block Diagram–An Example of Using NI-DSP Analysis VIs

Part 2: Introduction to the NI-DSP Analysis VIs 1-8 NI-DSP SRM for LabVIEW for Windows

Part 2 Introduction to the NI-DSP Analysis VIs

This example shows you how to obtain the power spectrum of a sine wave signal. First, generate a sine wave that you want to analyze using the LabVIEW Analysis VIs, then use the Copy Mem(LV to DSP) VI to copy the data of this sine signal to the DSP board. Before you copy the data, you must call the DSP Allocate Memory VI to allocate a DSP Handle Cluster that reserves a data buffer on the DSP board. Connect this DSP Handle Cluster to the destination in terminal of the Copy Mem(LV to DSP) VI to indicate where the data will be stored on the DSP board. After the data is copied to the DSP board, call the DSP Power Spectrum VI to perform a power spectrum on the data. After you finish the analysis, the results are stored in the data buffer indicated by the DSP Handle Cluster you previously allocated. If you want to see the results, call the Copy Mem(DSP to LV) VI to copy data back to LabVIEW. Figure 1-10 shows the power spectrum of a sine wave. The last step is to call the DSP Free Memory VI to free the DSP Handle Cluster that you allocated. This example connects all of the error out clusters of the previous VIs to the error in clusters of the subsequent VIs to establish the proper sequence and to pass through an error, should it occur, without executing the rest of the VIs.

NI-DSP SRM for LabVIEW for Windows 1-9 Part 2: Introduction to the NI-DSP Analysis VIs

Chapter 1 NI-DSP Analysis VI Reference Overview

This chapter contains an overview of the NI-DSP Analysis VIs and includes a list of the VIs. This chapter describes how the NI-DSP Analysis VIs are organized and how to access them.

The NI-DSP Analysis VI Overview

The NI-DSP Analysis VIs are a set of high-performance VIs that efficiently process large blocks of numerical data and perform numerically intensive computations. The NI-DSP Analysis VIs include numerical analysis, signal generation, digital signal processing, digital filtering, and windowing operations that are suitable for simulation, modeling, and sophisticated data processing.

The NI-DSP Analysis VIs are presented in alphabetical order in Chapter 2, NI-DSP Analysis VI Reference. Table 1-1 lists these VIs by group.

Table 1-1. The NI-DSP Analysis VI Groups

Signal Generation

DSP Sine Pattern DSP Pulse Pattern DSP Impulse Pattern DSP Impulse Train Pattern DSP Ramp Pattern DSP Sinc Pattern DSP Square Pattern DSP Triangle Pattern DSP Triangular Train DSP Sawtooth Pattern DSP Uniform White Noise DSP Random Pattern DSP Gaussian White Noise

Frequency Domain

DSP ReFFT DSP Complex FFT DSP Inverse FFT DSP Power Spectrum DSP Cross Power DSP FHT DSP Inverse FHT DSP Zero Padder

Time Domain

DSP Convolution DSP Deconvolution DSP Correlation DSP Decimate DSP Derivative DSP Integral

(continues)

NI-DSP SRM for LabVIEW for Windows 1-1 Part 3: NI-DSP Function Reference

NI-DSP Analysis VI Reference Overview Chapter 1

Table 1-1. The NI-DSP Analysis VI Groups (Continued)

Filters

DSP Butterworth Coefficients DSP Chebyshev Coefficients DSP Inverse Chebyshev Coeff DSP Elliptic Coefficients DSP IIR Filter DSP Equi-Ripple LowPass DSP Equi-Ripple HighPass DSP Equi-Ripple BandPass DSP Equi-Ripple BandStop DSP Parks-McClellan DSP Median Filter

Windows

DSP Blackman Window DSP Exact Blackman Window DSP Blackman Harris Window DSP Hanning Window DSP Hamming Window DSP Flat Top Window DSP General Cosine Window DSP Exponential Window DSP Force Window DSP Kaiser-Bessel Window DSP Triangular Window

Array Functions

DSP Add DSP Subtract DSP Multiply DSP Divide DSP Absolute DSP Square Root DSP Product DSP Sum DSP Log DSP Clip DSP Reverse DSP Shift DSP Sort DSP Linear Evaluation DSP Max & Min DSP Polynomial Evaluation DSP Subset DSP Set DSP Unwrap DSP Polar to Rectangular DSP Rectangular to Polar

Memory Management

DSP Allocate Memory Copy Mem(LV to DSP) Copy Mem(DSP to LV) Copy Mem(DSP to DSP) DSP Free Memory DSP Index Memory DSP Init Memory

Part 3: NI-DSP Function Reference 1-2 NI-DSP SRM for LabVIEW for Windows

Chapter 1 NI-DSP Analysis VI Reference Overview

Table 1-1. The NI-DSP Analysis VI Groups (Continued)

Utility Functions

DSP Reset DSP Load DSP Start DSP Timeout DSP Custom DSP DMA Copy(DSP to LV) DSP DMA Copy(LV to DSP) DSP Handle to Address

Analysis VI Organization

After installation, the NI-DSP Analysis VIs reside in the following VI library files (LabVIEW .LLB files) within the DSP2200 option:

• Signal Generation contains VIs that generate digital patterns.

• Frequency Domain contains VIs that perform frequency domain transformations, frequency domain analysis, and other transforms such as the Hartley transform.

• Time Domain contains VIs that perform direct time series analysis of signals.

• Filters contains VIs that perform IIR and FIR filtering functions.

• Windows contains VIs that perform smoothing windowing.

• Array contains VIs that perform arithmetic operations on arrays.

• Memory Management contains VIs to perform allocating, indexing, copying, and freeing memory on the AT-DSP2200 board.

• Utility contains VIs for controlling the operation of the AT-DSP2200 board.

After installation, the eight analysis VI libraries appear in the Functions menu in the order shown in the preceding list under the DSP2200 option. You can reorganize the folders and the VIs to suit your needs and applications.

Accessing the NI-DSP Analysis VIs

To access the analysis VIs from the block diagram window, choose DSP2200 from the Functions menu as shown in Figure 1-1, proceed through the hierarchical menus, and select the VI you want. The icon corresponding to that VI appears in the block diagram and is ready to be wired.

NI-DSP SRM for LabVIEW for Windows 1-3 Part 3: NI-DSP Function Reference

+ 127 hidden pages

National Instruments 320571-01 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Contents

Figures

Tables

About This Manual

Assumption of Previous Knowledge

Organization of This Manual

Conventions Used in This Manual

Related Documentation

Additional Software

NI-DAQ for DOS/Windows/LabWindows

Developer Toolkit

Compatible Hardware

Customer Communication

Part 1 Getting Started with NI-DSP

Product Overview

Figure 1-1. Development Paths with the NI-DSP Software

The NI-DSP Software

What Your Distribution Diskettes Should Contain

Installing NI-DSP for LabVIEW for Windows

Table 1-1. Subdirectories Created by SETUP

Board Configuration

Installation on an ISA (or AT) Bus Computer

Installation on an EISA Bus Computer

Part 2 Introduction to the NI-DSP Analysis VIs

Using the NI-DSP VIs in LabVIEW

AT-DSP2200 Software Overview

Figure 1-1. Communication between the PC and the DSP Board

Memory Management and Data Transfer

Figure 1-2. DSP Handle Cluster

Figure 1-3. The Hexadecimal Encoding of a Typical DSP Handle

Figure 1-4. Front Panel–An Example of How to Allocate a DSP Handle Cluster

Figure 1-5. Block Diagram–An Example of How to Allocate a DSP Handle Cluster

Special Features of the NI-DSP Analysis VIs

Figure 1-6. DSP Add VI

Figure 1-7. The error in/error out Cluster

Figure 1-8. An Example That Does Not Use error in/error out

Figure 1-9. An Example of Using the error in/error out Cluster for Sequential VI Execution

Hints for Improving the Execution Speed on the DSP Board

An Example of Using NI-DSP Analysis VIs

Figure 1-10. Front Panel–An Example of Using NI-DSP Analysis VIs

Figure 1-11. Block Diagram–An Example of Using NI-DSP Analysis VIs

Chapter 1 NI-DSP Analysis VI Reference Overview

The NI-DSP Analysis VI Overview

Table 1-1. The NI-DSP Analysis VI Groups

Analysis VI Organization

Accessing the NI-DSP Analysis VIs