National Instruments DAQCARD-700 User Manual

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DAQ

DAQCard™-700 User Manual

Multifunction I/O Devices for the PCMCIA Bus

DAQCard-700 User Manual

December 2001 Edition

Part Number 320676D-01

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For further support information, see the Technical Support Resources appendix. To comment on the documentation, send e-mail to techpubs@ni.com.

Important Information

Warranty

The DAQCard-700 is warranted against defects in materials and workmanship for a period of one year from the date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace equipment that proves to be defective during the warranty period. This warranty includes parts and labor.

The media on which you receive National Instruments software are warranted not to fail to execute programming instructions, due to defects in materials and workmanship, for a period of 90 days from date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace software media that do not execute programming instructions if National Instruments receives notice of such defects during the warranty period. National Instruments does not warrant that the operation of the software shall be uninterrupted or error free.

A Return Material Authorization (RMA) number must be obtained from the factory and clearly marked on the outside of the package before any equipment will be accepted for warranty work. National Instruments will pay the shipping costs of returning to the owner parts which are covered by warranty.

National Instruments believes that the information in this document is accurate. The document has been carefully reviewed for technical accuracy. In the event that technical or typographical errors exist, National Instruments reserves the right to make changes to subsequent editions of this document without prior notice to holders of this edition. The reader should consult National Instruments if errors are suspected. In no event shall National Instruments be liable for any damages arising out of or related to this document or the information contained in it.

XCEPT AS SPECIFIED HEREIN,NATIONAL INSTRUMENTS MAKES NO WARRANTIES, EXPRESS OR IMPLIED, AND SPECIFICALLY DISCLAIMS ANY WARRANTY OF

MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE

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DAMAGES RESULTING FROM LOSS OF DATA

. This limitation of the liability of National Instruments will apply regardless of the form of action, whether in contract or tort, including

THEREOF

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, PROFITS, USE OF PRODUCTS, OR INCIDENTAL OR CONSEQUENTIAL DAMAGES, EVEN IF ADVISED OF THE POSSIBILITY

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Under the copyright laws,this publication may not be reproduced or transmitted in any form, electronic ormechanical, including photocopying, recording, storing in an information retrieval system, or translating, in whole or in part, without the prior written consent of National Instruments Corporation.

Trademarks

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Product and company names mentioned herein are trademarks or trade names of their respective companies.

Patents

For patents covering National Instruments products, refer to the appropriate location: Help»Patents in your software, the on your CD, or

ni.com/patents

WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS

(1) NATIONAL INSTRUMENTS PRODUCTS ARE NOT DESIGNED WITH COMPONENTS AND TESTING FOR A LEVEL OF RELIABILITY SUITABLE FOR USE IN OR IN CONNECTION WITH SURGICAL IMPLANTS OR AS CRITICAL COMPONENTS IN ANY LIFE SUPPORT SYSTEMS WHOSE FAILURE TO PERFORM CAN REASONABLY BE EXPECTED TO CAUSE SIGNIFICANT INJURY TO A HUMAN.

(2) IN ANY APPLICATION, INCLUDING THE ABOVE, RELIABILITY OF OPERATION OF THE SOFTWARE PRODUCTS CAN BE IMPAIRED BY ADVERSE FACTORS, INCLUDING BUT NOT LIMITED TO FLUCTUATIONS IN ELECTRICAL POWER SUPPLY, COMPUTER HARDWARE MALFUNCTIONS, COMPUTER OPERATING SYSTEM SOFTWARE FITNESS, FITNESS OF COMPILERS AND DEVELOPMENT SOFTWARE USED TO DEVELOP AN APPLICATION, INSTALLATION ERRORS, SOFTWARE AND HARDWARE COMPATIBILITY PROBLEMS, MALFUNCTIONS OR FAILURES OF ELECTRONIC MONITORING OR CONTROL DEVICES, TRANSIENT FAILURES OF ELECTRONIC SYSTEMS (HARDWARE AND/OR SOFTWARE), UNANTICIPATED USES OR MISUSES, OR ERRORS ON THE PART OF THE USER OR APPLICATIONS DESIGNER (ADVERSE FACTORS SUCH AS THESE ARE HEREAFTER COLLECTIVELY TERMED “SYSTEM FAILURES”). ANY APPLICATION WHERE A SYSTEM FAILURE WOULD CREATE A RISK OF HARM TO PROPERTY OR PERSONS (INCLUDING THE RISK OF BODILY INJURY AND DEATH) SHOULD NOT BE RELIANT SOLELY UPON ONE FORM OF ELECTRONIC SYSTEM DUE TO THE RISK OF SYSTEM FAILURE. TO AVOID DAMAGE, INJURY, OR DEATH, THE USER OR APPLICATION DESIGNER MUST TAKE REASONABLY PRUDENT STEPS TO PROTECT AGAINST SYSTEM FAILURES, INCLUDING BUT NOT LIMITED TO BACK-UP OR SHUT DOWN MECHANISMS. BECAUSE EACH END-USER SYSTEM IS CUSTOMIZED AND DIFFERS FROM NATIONAL INSTRUMENTS' TESTING PLATFORMS AND BECAUSE A USER OR APPLICATION DESIGNER MAY USE NATIONAL INSTRUMENTS PRODUCTS IN COMBINATION WITH OTHER PRODUCTS IN A MANNER NOT EVALUATED OR CONTEMPLATED BY NATIONAL INSTRUMENTS, THE USER OR APPLICATION DESIGNER IS ULTIMATELY RESPONSIBLE FOR VERIFYING AND VALIDATING THE SUITABILITY OF NATIONAL INSTRUMENTS PRODUCTS WHENEVER NATIONAL INSTRUMENTS PRODUCTS ARE INCORPORATED IN A SYSTEM OR APPLICATION, INCLUDING, WITHOUT LIMITATION, THE APPROPRIATE DESIGN, PROCESS AND SAFETY LEVEL OF SUCH SYSTEM OR APPLICATION.

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patents.txt

file

About This Manual

Conventions ...................................................................................................................vii

National Instruments Documentation ............................................................................viii

Chapter 1 Introduction

About the DAQCard-700...............................................................................................1-1

What You Need to Get Started ......................................................................................1-2

Software Programming Choices ....................................................................................1-2

NI-DAQ...........................................................................................................1-2

National Instruments ADE Software............................................................... 1-3

Custom Cabling .............................................................................................................1-4

Unpacking......................................................................................................................1-5

Safety Information .........................................................................................................1-5

Chapter 2 Installing and Configuring the DAQCard-700

Installing the Software ................................................................................................... 2-1

Installing the Hardware..................................................................................................2-1

Configuring the DAQCard-700 .....................................................................................2-3

Configuring Analog Input ...............................................................................2-3

Analog Input Mode ...........................................................................2-4

Configuring Digital I/O ...................................................................................2-5

Configuring Counters ......................................................................................2-5

Chapter 3 Connecting Signals

I/O Connector ................................................................................................................3-1

Signal Connection Descriptions.....................................................................................3-2

Connecting Analog Input Signals....................................................................3-3

Types of Signal Sources....................................................................3-4

Measurement System Types .............................................................3-4

Input Configurations .........................................................................3-5

Recommended Input Configurations ................................................3-7

Single-Ended Connection Considerations ........................................3-7

Differential Connection Considerations............................................ 3-9

Contents

Connecting Digital I/O Signals ....................................................................... 3-13

Connecting Power ...........................................................................................3-14

Connecting Timers.......................................................................................... 3-15

Chapter 4 Theory of Operation

Functional Overview ..................................................................................................... 4-1

PCMCIA I/O Channel Interface Circuitry .................................................................... 4-3

Analog Input and Data Acquisition Circuitry ............................................................... 4-4

Analog Input Circuitry .................................................................................... 4-5

Data Acquisition Timing Circuitry ................................................................. 4-6

Digital I/O Circuitry ...................................................................................................... 4-8

Timing I/O Circuitry...................................................................................................... 4-9

Appendix A

Data Acquisition Counter and Timing Connections......................... 3-15

General-Purpose Counter and Timing Signal Connections.............. 3-16

Single-Channel Data Acquisition ..................................................... 4-7

Multichannel (Scanned) Data Acquisition ....................................... 4-7

Data Acquisition Rates ..................................................................... 4-7

Specifications

Appendix B Differences between the PC-LPM-16 and the DAQCard-700

Appendix C Common Questions

Appendix D Technical Support Resources

Glossary

Index

DAQCard-700 User Manual vi ni.com

About This Manual

This manual describes the mechanical and electrical aspects of the National

Instruments (NI) DAQCard-700 and contains information concerning its

installation and operation. The DAQCard-700 is a compact, low-cost,

low-power analog input (AI), digital I/O (DIO), and timing I/O (TIO) card

for computers that are equipped with a Type II PCMCIA socket.

Conventions

The following conventions appear in this manual:

<> Angle brackets that contain numbers separated by an ellipsis represent

a range of values associated with a bit or signal name—for example,

DBIO<3..0>.

» The » symbol leads you through nested menu items and dialog box options

to a final action. The sequence File»Page Setup»Options directs you to

pull down the File menu, select the Page Setup item, and select Options

from the last dialog box.

This icon denotes a note, which alerts you to important information.

This icon denotes a caution, which advises you of precautions to take to

avoid injury, data loss, or a system crash. When this symbol is marked on

the product, refer to the Safety Information section of Chapter 1,

Introduction, for precautions to take.

bold Bold text denotes items that you must select or click on in the software,

such as menu items and dialog box options. Bold text also denotes

parameter names.

italic Italic text denotes variables, emphasis, a cross reference, or an introduction

to a key concept. This font also denotes text that is a placeholder for a word

or value that you must supply.

monospace

Text in this font denotes text or characters that you should enter 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, functions, operations,

variables, filenames and extensions, and code excerpts.

About This Manual

PC PC refers to all PC AT series computers with PCI or PXI bus unless

otherwise noted.

PCMCIA PCMCIA is an international standards body and trade association that

promotes the interoperability of PC cards.

Platform

Text in this font denotes a specific platform and indicates that the text following it applies only to that platform.

National Instruments Documentation

The DAQCard-700 User Manual is one piece of the documentation set for the data acquisition (DAQ) system. You could have any of several types of manuals, depending on the hardware and software in the system. Use the manuals you have as follows:

• Hardware documentation—This documentation has detailed information about the DAQ hardware that plugs into or is connected to the computer. Use this documentation for hardware installation and configuration instructions, specification information about the DAQ hardware, and application hints.

• Software documentation—You may have both application software and NI-DAQ documentation. After you set up the hardware, use either the application software documentation or the NI-DAQ documentation to help you write your application. NI application software includes LabVIEW and Measurement Studio. If you have a large, complicated system, it is worthwhile to look through the software documentation before you configure the hardware.

• Accessory installation guides or manuals—If you are using accessory products, read the cable assembly installation guides. They explain how to physically connect the relevant pieces of the system. Consult these guides when you make the connections.

DAQCard-700 User Manual viii ni.com

Introduction

This chapter discusses what you need to get started, optional software, optional equipment, how to unpack the DAQCard-700, and safety information for using the device.

About the DAQCard-700

The DAQCard-700 is a low-cost, low-power AI, DIO, and TIO card for computers equipped with a Type II PCMCIA slot. The card has the following features:

• A 12-bit, successive-approximation A/D converter (ADC) with 16 single-ended or 8 differential analog inputs

• 16 DIO channels: eight lines of TTL-compatible digital input and eight lines of digital output

• Two 16-bit counter/timer channels for TIO

• A MSM82C54 counter/timer integrated circuit, which provides three

integrated counter/timers

• An optional 50-pin I/O connector, which enables you to easily connect all the analog, digital, and timing signals to the card

The DAQCard-700 is fully software configurable and factory calibrated.

The low power consumption of the DAQCard-700 makes the card ideal for portable computers, making remote data acquisition more practical. The card requires very little power when operating and has a standby mode that uses even less power, thus extending the computer battery life.

In addition, the low cost of a system based on the DAQCard-700 makes it ideal for laboratory work. The multiple-channel AI capability is useful in signal analysis and data logging. The 12-bit ADC is suited for high-resolution applications such as chromatography, temperature measurement, and DC voltage measurement. The 16 TTL-compatible DIO lines can be used for switching external devices such as transistors and solid-state relays, for reading the status of external digital logic, and for generating interrupts. The counter/timers can be used to synchronize events, generate pulses, and measure frequency and time.

Chapter 1 Introduction

Detailed specifications of the DAQCard-700 are in Appendix A,

Specifications.

What You Need to Get Started

To set up and use the DAQCard-700, you will need the following:

❑

DAQCard-700

❑

DAQCard-700 I/O cable

❑ DAQCard-700 User Manual

❑

One of the following software packages and documentation:

– LabVIEW

– Measurement Studio

(for Windows or Mac OS)

(for Windows)

❑

NI-DAQ

❑

The computer

(for PC compatibles or Mac OS)

Software Programming Choices

When programming the National Instruments DAQ hardware, you can use NI application development environment (ADE) software or other ADEs. In either case, you use NI-DAQ.

NI-DAQ

NI-DAQ ships with the DAQCard-700 and has an extensive library of functions that you can call from your ADE. These functions allow you to use all the features of the DAQCard-700.

NI-DAQ carries out many of the complex interactions, such as programming interrupts, between the computer and the DAQ hardware. NI-DAQ maintains a consistent software interface among its different versions so that you can change platforms with minimal modifications to your code. Whether you use LabVIEW, Measurement Studio, or other ADEs, your application uses NI-DAQ, as illustrated in Figure 1-1.

DAQCard-700 User Manual 1-2 ni.com

Chapter 1 Introduction

Conventional Programming

Environment

DAQ Hardware

Figure 1-1.

NI-DAQ

Driver Software

The Relationship Between the Programming Environment,

NI-DAQ, and Your Hardware

LabVIEW or

Measurement Studio

Personal

Computer or

Workstation

To download a free copy of the most recent version of NI-DAQ, click Download Software at

ni.com

National Instruments ADE Software

LabVIEW features interactive graphics, a state-of-the-art interface, and a powerful graphical programming language. The LabVIEW Data Acquisition VI Library, a series of virtual instruments (VIs) for using LabVIEW with National Instruments DAQ hardware, is included with LabVIEW.

Measurement Studio, which includes LabWindows/CVI, tools for Visual C++, and tools for Visual Basic, is a development suite that allows you to use ANSI C, Visual C++, and Visual Basic to design your test and measurement software. For C developers, Measurement Studio includes LabWindows/CVI, a fully integrated ANSI C application development environment that features interactive graphics and the LabWindows/CVI Data Acquisition and Easy I/O libraries. For Visual Basic developers,

Chapter 1 Introduction

Custom Cabling

Measurement Studio features a set of ActiveX controls for using National Instruments DAQ hardware. These ActiveX controls provide a high-level programming interface for building virtual instruments. For Visual C++ developers, Measurement Studio offers a set of Visual C++ classes and tools to integrate those classes into Visual C++ applications. The libraries, ActiveX controls, and classes are available with Measurement Studio and NI-DAQ.

Using LabVIEW or Measurement Studio greatly reduces the development time for your data acquisition and control application.

NI offers two cables, the PR-50-50F and the PR-50-50M, and one cable termination accessory, the CB-50, for use with the DAQCard-700. The CB-50 kit includes a terminated, 50-conductor, flat ribbon cable and a connector block. You can attach signal input and output wires to screw terminals on the connector block and therefore to the DAQCard-700 I/O connector.

The CB-50 is useful for the initial prototyping of an application or in situations in which the DAQCard-700 interconnections are frequently changed. After you develop a final field wiring scheme, however, you may want to develop your own cable. This section contains information and guidelines for the design of custom cables.

The PR-50-50M terminates in a 50-pin, male ribbon cable header connector, and the PR-50-50F terminates in a 50-pin, female ribbon cable socket connector. The mating connector for each cable is a 50-position, polarized, ribbon-socket header. For the PR-50-50M, the mating connector has strain relief. NI uses a polarized (keyed) connector for each cable to prevent inadvertent upside-down connections to the DAQCard-700.

The PCMCIA I/O cable connector, like the card connector attached to the card itself, is a custom-designed part. It is only available as part of the PR-50-50 cable assembly.

DAQCard-700 User Manual 1-4 ni.com

Unpacking

Chapter 1 Introduction

TheDAQCard-700isshippedinanantistaticpackagetoprevent electrostatic damage to the device.

Caution

of connectors.

To avoid electrostatic damage to the DAQCard-700, never touch the exposed pins

Because the DAQCard-700 is enclosed in a fully shielded case, no additional electrostatic precautions are necessary.

Remove the DAQCard-700 from the package and inspect the device for loose components or any sign of damage. Notify NI if the DAQCard-700 appears damaged in any way. Do not install a damaged device into your computer.

Store the DAQCard-700 in the antistatic envelope when not in use.

Safety Information

The following section contains important safety information that you must follow when installing and using the product.

Do not operate the product in a manner not specified in this document. Misuse of the product can result in a hazard. You can compromise the safety protection built into the product if the product is damaged in any way. If the product is damaged, return it to NI for repair.

Do not substitute parts or modify the product except as described in this document. Use the product only with the chassis, modules, accessories, and cables specified in the installation instructions. You must have all covers and filler panels installed during operation of the product.

Do not operate the product in an explosive atmosphere or where there may be flammable gases or fumes. Operate the product only at or below the pollution degree stated in Appendix A, Specifications. Pollution is foreign matter in a solid, liquid, or gaseous state that can reduce dielectric strength or surface resistivity. The following is a description of pollution degrees:

• Pollution degree 1 means no pollution or only dry, nonconductive pollution occurs. The pollution has no influence.

Chapter 1 Introduction

• Pollution degree 2 means that only nonconductive pollution occurs in most cases. Occasionally, however, a temporary conductivity caused by condensation must be expected.

• Pollution degree 3 means that conductive pollution occurs, or dry, nonconductive pollution occurs that becomes conductive due to condensation.

Clean the product with a soft nonmetallic brush. Make sure that the product is completely dry and free from contaminants before returning it to service.

Yo u must insulate signal connections for the maximum voltage for which the product is rated. Do not exceed the maximum ratings for the product. Remove power from signal lines before connecting them to or disconnecting them from the product.

Operate this product only at or below the installation category stated in Appendix A, Specifications.

The following is a description of installation categories:

• Installation category I is for measurements performed on circuits not directly connected to MAINS

. This category is a signal level such as voltages on a printed wire board (PWB) on the secondary of an isolation transformer.

Examples of installation category I are measurements on circuits not derived from MAINS and specially protected (internal) MAINS-derived circuits.

• Installation category II is for measurements performed on circuits directly connected to the low-voltage installation. This category refers to local-level distribution such as that provided by a standard wall outlet.

Examples of installation category II are measurements on household appliances, portable tools, and similar equipment.

• Installation category III is for measurements performed in the building installation. This category is a distribution level referring to hardwired equipment that does not rely on standard building insulation.

Examples of installation category III include measurements on distribution circuits and circuit breakers. Other examples of installation category III are wiring including cables, bus-bars,

MAINS is defined as the electricity supply system to which the equipment concerned is designed to be connected either for powering the equipment or for measurement purposes.

DAQCard-700 User Manual 1-6 ni.com

Chapter 1 Introduction

junction boxes, switches, socket outlets in the building/fixed installation, and equipment for industrial use, such as stationary motors with a permanent connection to the building/fixed installation.

• Installation category IV is for measurements performed at the source of the low-voltage (<1,000 V) installation.

Examples of category IV are electric meters, and measurements on primary overcurrent protection devices and ripple-control units.

Below is a diagram of a sample installation.

Installing and Configuring the DAQCard-700

This chapter describes how to install and configure the DAQCard-700.

Installing the Software

Install the ADE, such as LabVIEW or Measurement Studio, according to the instructions on the CD and the release notes. After you have installed the ADE, install NI-DAQ according to the instructions on the CD and the DAQ Quick Start Guide included with the DAQCard-700.

Note

It is important to install NI-DAQ before installing the DAQCard-700 to ensure that

the DAQCard-700 is properly detected.

Installing the Hardware

The following are general installation instructions. Consult the computer user manual or technical reference manual for specific instructions and warnings about installing new devices. Refer to Figure 2-1 when installing the DAQCard-700.

1. Power off the computer.

Note

You must have Card & Socket Services 2.0 or later on the computer.

The DAQCard-700 requires a 32-byte I/O address window and one interrupt level.

2. Insert the DAQCard-700 in any available Type II PC Card slot until the connector is firmly seated. The DAQCard-700 has two connectors—a 68-pin PCMCIA bus connector on one end and a 50-pin I/O connector on the other end.

Note

If the computer supports hot swapping, you may insert or remove the DAQCard-700

at any time, whether the computer is powered on or off.

Chapter 2 Installing and Configuring the DAQCard-700

3. Visually verify the installation by making sure that the DAQCard-700 isfullyinsertedintotheslot.

4. Attach the DAQCard-700 I/O cable.

Note

Be careful not to put strain on the I/O cable when inserting it into and removing it from the DAQCard-700. Always grasp the cable by the connector you are plugging or unplugging. Never pull directly on the I/O cable to unplug it from the DAQCard-700.

5. Plug in and power on the computer.

The DAQCard-700 is now installed. You are now ready to configure the hardware and software and to make the appropriate connections to the I/O connector cable as described in Chapter 3, Connecting Signals.

Figure 2-1 shows an example of a typical configuration.

Portable

Computer

PCMCIA Socket

DAQCard-700

I/O Cable

CB-50

I/O Signals

Figure 2-1. A Typical Configuration for the DAQCard-700

DAQCard-700 User Manual 2-2 ni.com

Configuring the DAQCard-700

Because of the standard NI architecture for data acquisition, the DAQCard-700 is completely software configurable.

Data acquisition-related configuration, which you must perform, includes settings such as AI coupling and range. You can modify these settings using NI-DAQ or application-level software, such as LabVIEW and Measurement Studio.

To configure the device in Measurement & Automation Explorer (MAX), refer to the DAQ Quick Start Guide or to the NI-DAQ Function Reference Help file.

Configuring Analog Input

At startup, the DAQCard-700 defaults to the following configuration:

• Referenced single-ended (RSE) input mode

• ±10 V AI range

Table 2-1 lists the available AI configurations for the DAQCard-700 and shows the default settings.

Chapter 2 Installing and Configuring the DAQCard-700

Table 2-1.

Parameter Configuration

Analog Input Polarity Bipolar—±10 V (default setting)

Analog Input Mode RSE (default setting)

The AI circuitry is software configurable.

Caution

any of the maximum signal ratings on the DAQCard-700 can result in damage to the DAQCard-700. NI is not liable for any injuries or damage resulting from incorrect signal connections.

Connections, including power signals to ground and vice versa, that exceed

Analog I/O Settings

Bipolar—±5 V Bipolar—±2.5 V

Differential (DIFF)

Chapter 2 Installing and Configuring the DAQCard-700

Analog Input Mode

The DAQCard-700 has two input modes: RSE and DIFF. RSE input mode provides 16 channels. DIFF input mode provides eight channels. Table 2-2 describes these modes.

Table 2-2. Analog Input Modes for the DAQCard-700

Analog Input

Modes

RSE Referenced single-ended mode provides

DIFF Differential mode provides eight differential inputs

Description

16 single-ended inputs referenced to analog ground (default setting).

with the positive (+) input of the instrumentation amplifier tied to channels 0, 1, 2, 3, 4, 5, 6, or 7 and thenegative(–) input tied to channels 8, 9, 10, 11, 12, 13, 14, or 15, respectively, thus choosing channel pairs (0, 8), (1, 9), (2, 10), (3, 11), (4, 12), (5, 13), (6, 14), or (7, 15).

While reading the following paragraphs, you may find it helpful to refer to the Connecting Analog Input Signals section of Chapter 3, Connecting

Signals, which contains diagrams showing the signal paths for the

two modes. These two modes are software-selectable.

RSE Input Mode (16 Channels, Default Setting)

RSE input mode means that all input signals are referenced to a common ground point that is also tied to the DAQCard-700 AI ground. The RSE configuration is useful for measuring floating signal sources. See the Types

of Signal Sources section of Chapter 3, Connecting Signals,formore

information. With this input configuration, the DAQCard-700 can monitor 16 different AI channels.

Considerations for using the RSE input mode are discussed in Chapter 3,

Connecting Signals. Notice that in this mode, the return path of the signal

is analog ground at the connector through the AIGND pin.

DAQCard-700 User Manual 2-4 ni.com

DIFF Input Mode (Eight Channels)

DIFF input mode means that each input signal has its own reference, and the difference between each signal and itsreference is measured. The signal and its reference are each assigned an input channel.

Considerations for using DIFF input mode are discussed in Chapter 3,

Connecting Signals. Notice that the signal return path is through the

negative terminal of the instrumentation amplifier and through channel 8, 9, 10, 11, 12, 13, 14, or 15, depending on which channel pair you select.

Configuring Digital I/O

The DAQCard-700 always uses one 8-bit digital output port and one 8-bit digital input port.

Configuring Counters

You can use the MSM82C54 for general-purpose applications, such as pulse and square wave generation, event counting, and pulse-width, time-lapse, and frequency measurements. For information about configuring the MSM82C54, refer to the Connecting Timers section of Chapter 3, Connecting Signals.

Chapter 2 Installing and Configuring the DAQCard-700

Connecting Signals

This chapter describes the DAQCard-700 I/O connector signals and typical cable setups.

I/O Connector

Figure 3-1 shows the pin assignments for the DAQCard-700 I/O connector. This connector is attached to the ribbon cable that extends from the PCMCIA slot when the card is installed and the cable is connected.

Caution

any of the maximum signal ratings on the DAQCard-700 can result in damage to the DAQCard-700. NI is not liable for any injuries or damage resulting from incorrect signal connections.

Connections, including power signals to ground and vice versa, that exceed

Chapter 3 Connecting Signals

AIGND

ACH0 ACH1 ACH2 ACH3 ACH4 ACH5 ACH6 ACH7

DGND

NC DIN1 DIN3 DIN5 DIN7

DOUT1 DOUT3 DOUT5 DOUT7

EXTINT*

OUT0 OUT1

CLK1

GATE2

+5 V

11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49

1 3 5 7 9

4 6

8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50

AIGND ACH8 ACH9 ACH10 ACH11 ACH12 ACH13 ACH14 ACH15 NC DIN0 DIN2 DIN4 DIN6 DOUT0 DOUT2 DOUT4 DOUT6 OUT1* EXTCONV* GATE0 GATE1 OUT2 CLK2 DGND

Figure 3-1. DAQCard-700 I/O Connector Pin Assignments

Signal Connection Descriptions

Pin Signal Name Direction Description

1–2 AIGND — Analog Input Ground—These pins are connected to the

AI ground signal.

3–18 ACH<0..15> Input Analog Input Channels 0 through 15—These channels are

available in single-ended mode.

19 DGND — Digital Ground—This pin is connected to the digital ground

signal.

20–21 NC — Not Connected—These pins are not connected.

22–29 DIN<0..7> Input Input Digital Data Lines 0 through 7—DIN7 is the MSB

DAQCard-700 User Manual 3-2 ni.com

(most significant bit), DIN0 the LSB (least significant bit).

Chapter 3 Connecting Signals

Pin Signal Name Direction Description

30–37 DOUT<0..7> Output Output Digital Data Lines 0 through 7—DOUT7 is the MSB,

DOUT0 the LSB.

38 OUT1* Output Counter 1 Output—This pin is the inversion of counter 1

output.

39 EXTINT* Input External Interrupt—This pin is used for input of the external

interrupt signal.

40 EXTCONV* Input External Control—This pin is used for input of the external

control signal to trigger A/D conversions.

41 OUT0 Output Counter 0 Output—This pin is the output of counter 0.

42 GATE0 Input Counter 0 Gate Input—This pin is the gate input for counter 0.

43 OUT1 Output Counter 1 Output—This pin is the output of counter 1.

44 GATE1 Input Counter 1 Gate Input—This pin is the gate input for counter 1.

45 CLK1 Input Counter 1 Clock Input—This pin is the clock input for

46 OUT2 Output Counter 2 Output—This pin is the output of counter 2.

47 GATE2 Input Counter 2 Gate Input—This pin is the gate input for counter 2.

48 CLK2 Input Counter 2 Clock Input—This pin is the clock input for

49 +5 V Output +5 Volts—This pin provides +5 VDC. The +5 V supply is

50 DGND — Digital Ground—This pin is connected to the digital ground

* Indicates that the signal is active low.

counter 1.

counter 2.

fused at 1 A, which is the maximum current available.

signal.

The connector pins can be grouped into AI signal pins, DIO signal pins, and TIO signal pins. Signal connection guidelines for each of these groups are included in the following pages.

Connecting Analog Input Signals

Pins 1 through 18 are AI signal pins for the ADC. Pins 1 and 2, named AIGND, are an analog common signal. You can use these pins for a general analog power ground tie to the DAQCard-700. Pins 3 through 18 are the ACH<0..15> signal pins. These pins are tied to the AI channels of the DAQCard-700 through 4.7 kΩ series resistors. These resistors limit the input current to the multiplexer. Refer to Appendix A, Specifications,for input ranges and maximum ratings for the analog inputs, ACH<0..15>.

Chapter 3 Connecting Signals

Caution

input voltage rating may damage the DAQCard-700 card and the computer. NI is not liable for any damage resulting from such signal connections.

Exceeding the input signal range distorts input signals. Exceeding the maximum

Types of Signal Sources

When configuring the input mode of the DAQCard-700 and making signal connections, first determine whether the signal source and the measurement system are floating or ground referenced. The two signal source types are described as follows, and the types of measurement systems are described in later sections.

Ground-Referenced Signal Sources

A ground-referenced signal source is one that is connected to the building system ground. Nonisolated outputs of instruments and devices that plug into the building power system fall into this category.

The difference in ground potential between two instruments connected to the same building power system is typically between 1 and 100 mV but can be much higher if power-distribution circuits are improperly connected. The connection instructions described later in this chapter for grounded signal sources are designed to eliminate this ground potential difference from the measured signal.

Floating Signal Sources

A floating, or nonreferenced, signal source is one that is not connected in any way to the building ground system and has instead an isolated ground-reference point. Some examples of floating signal sources are outputs of transformers, thermocouples, battery-powered devices, optical isolator outputs, and isolation amplifiers. The ground reference of a floating signal must be tied to the DAQCard-700 AI ground to establish a local or onboard reference for the signal. Otherwise, the measured input signal varies or appears to float. An instrument or device that provides an isolated output falls into the floating signal source category.

Measurement System Types

In addition to determining the signal source type, you must also determine whether the measurement system is ground-referenced or floating. These two measurement system types are described below. Depending on the power connection, a portable computer can represent either a ground-referenced or floating measurement system. If a portable computer is entirely battery powered, it is a floating system. If it is operated from an

DAQCard-700 User Manual 3-4 ni.com

Chapter 3 Connecting Signals

AC/DC wall adapter, it may be ground referenced, depending on the connection. You should determine from the computer documentation whether any of the power connections are tied to the building power system ground.

Ground-Referenced Measurement System

A ground-referenced measurement system is one that is connected in some way to the building system ground. Instruments that plug into the building power system fall into this category.

Floating Measurement System

A floating, or nonreferenced, measurement system is one that is not connected in any way to the building ground system but rather has an isolated ground-reference point. Some examples of floating measurement systems are battery-powered instruments, instruments powered with a nonground-referenced power adapter, and instruments with differential inputs. A floating measurement system will float to the level of the signals being measured.

Input Configurations

To measure different types of input signals, you can configure the DAQCard-700 for one of two input modes—DIFF or RSE. These two modes can be implemented by changing the configuration of the instrumentation amplifier onboard the DAQCard-700. Figure 3-2 shows a diagram of the DAQCard-700 instrumentation amplifier.

Figure 3-2.

DAQCard-700 Instrumentation Amplifier

Instrumentation Amplifier

V=[V

– V

Measured Voltage

] GAIN

Chapter 3 Connecting Signals

The DAQCard-700 instrumentation amplifier applies common-mode voltage rejection and presents a high-input impedance to the AI signals connected to the DAQCard-700. Signals are routed to the positive and negative inputs of the instrumentation amplifier through input multiplexers on the DAQCard-700. The instrumentation amplifier converts two input signals to a signal that is the difference between the two input signals multiplied by the gain setting of the amplifier. The amplifier output voltage is referenced to the DAQCard-700 ground. The DAQCard-700 ADC measures this output voltage when it performs A/D conversions.

Single-Ended Mode (RSE)

Although the instrumentation amplifier on the DAQCard-700 is actually bypassed in RSE input mode, the effect of this mode is the same as if signals connected to ACH<0..15> were routed to the positive terminal of the instrumentation amplifier and the negative terminal of the instrumentation amplifier were connected to the analog ground reference of the DAQCard-700. Thus, the voltage measured by the DAQCard-700 in RSE input mode is the difference between an input signal and the DAQCard-700 analog ground reference.

Differential Mode (DIFF)

In DIFF input mode, signals connected to ACH<0..7> are routed to the positive input of the instrumentation amplifier, and signals connected to ACH<8..15> are routed to the negative input of the instrumentation amplifier. Thus, the voltage measured by the DAQCard-700 in DIFF input mode is the difference between two of the input signals.

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Chapter 3 Connecting Signals

Recommended Input Configurations

The following sections discuss the use of RSE and DIFF measurements and considerations for measuring both floating and ground-referenced signal sources. Table 3-1 summarizes the recommended input configurations for both signal source types.

Table 3-1. Recommended Input Configurations for Ground-Referenced and Floating Measurement Systems

Recommended Input

System Type Type of Signal

Configurations

Ground-referenced system, such as a desktop computer

Floating system, such as a battery-powered computer

Ground referenced (nonisolated outputs, plug-in instruments)

Floating (batteries, thermocouples, isolated outputs)

Ground referenced (nonisolated outputs, plug-in instruments)

Floating (batteries, thermocouples, isolated outputs)

DIFF with bias resistors

DIFF

RSE

Single-Ended Connection Considerations

Single-ended connections are those in which all DAQCard-700 AI signals are referenced to one common ground. The input signals are tied to the positive input of an operational amplifier that is referenced to the common ground point.

When the DAQCard-700 is configured for RSE input mode, 16 AI channels are available. You can use single-ended input connections when the following criteria are met by all input signals:

• Input signals are high level (greater than 1 V).

• Leads connecting the signals to the DAQCard-700 are less than 15 ft.

• All input signals share a common reference signal (at the source).

If any of the preceding criteria are not met, use the DIFF input mode.

The RSE input mode is referenced, but you can use this mode for nonreferenced signal sources. In addition, if the computer using the

Chapter 3 Connecting Signals

DAQCard-700 is not ground referenced, you can use this mode for ground-referenced signal sources.

Figure 3-3 shows how to connect a signal source to a DAQCard-700 in RSE input mode. When you connect grounded signal sources to a DAQCard-700 in a ground-referenced computer, carefully observe the polarity to avoid shorting the signal source output. A laptop operating from a battery is not grounded. A laptop powered from an AC/DC adapter may or may not be grounded.

Signal

Source

I/O Connector

1, 2

AIGND

ACH<0..15>

Input Multiplexer

Operational

Amplifier

Measured

Voltage

DAQCard-700

Figure 3-3. Single-Ended Analog Input Signal Connections

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Chapter 3 Connecting Signals

Differential Connection Considerations

Differential connections are those in which each DAQCard-700 AI signal has its own reference signal or signal return path. These connections are available when the DAQCard-700 is configured in the DIFF mode. Each input signal is tied to the positive input of the instrumentation amplifier, and its reference signal, or return, is tied to the negative input of the instrumentation amplifier.

When the DAQCard-700 is configured for DIFF input mode, each signal uses two of the multiplexer inputs—one for the signal and one for its reference signal. Therefore, only eight AI channels are available when using DIFF input mode. DIFF input mode should be used when any of the following conditions are present:

• Input signals are low-level (less than 1 V).

• Leads connecting signals to the DAQCard-700 are greater than 15 ft.

• Any of the input signals requires a separate ground reference point or

return signal.

• The signal leads travel through noisy environments.

Differential signal connections reduce noise pickup and increase common-mode noise rejection. With these connections, input signals can float within the common-mode limits of the input instrumentation amplifier.

Chapter 3 Connecting Signals

Grounded-

Referenced

Signal

Source

Differential Connections for Grounded Signal Sources

Figure 3-4 shows how to connect a ground-referenced signal source to a DAQCard-700 card configured for DIFF input.

ACH<0..7>

Instrumentation

Amplifier

Common-Mode

Noise,

Ground

Potential,

and so on

I/O Connector

ACH<8..15>

Input Multiplexers

1,2

AIGND

DAQCard-700 Device in DIFF Configuration

Measured

Voltage

Figure 3-4. Differential Input Connections for Grounded Signal Sources

With this type of connection, the instrumentation amplifier rejects both the common-mode noise in the signal and the ground potential difference between the signal source and the DAQCard-700 ground (shown as V

Figure 3-4).

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Chapter 3 Connecting Signals

Differential Connections for Floating Signal Sources

Figure 3-5 shows how to connect a floating signal source to a DAQCard-700 configured for DIFF input mode. Configuration instructions are included in the Input Configurations section.

ACH<0..7>

Floating

Signal

Source

Bias

Current

Return

Paths

I/O Connector

ACH<8..15>

Input Multiplexers

1, 2

DAQCard-700 Device in DIFF Configuration

Figure 3-5.

Differential Input Connections for Floating Sources

AIGND

Instrumentation

Amplifier

Measured

Voltage

The 100 kΩ resistors shown in Figure 3-5 create a return path to ground for the bias currents of the instrumentation amplifier. If a return path is not provided, the instrumentation amplifier bias currents cause stray capacitances, resulting in uncontrollable drift and possible saturation in the amplifier. Typically, values from 10 kΩ to 100 kΩ are used.

Chapter 3 Connecting Signals

A resistor from each input to ground, as shown in Figure 3-5, provides bias current return paths for an AC-coupled input signal. This solution, although necessary for AC-coupled signals, lowers the input impedance of the AI channel. In addition, the input offset current of the instrumentation amplifier contributes a DC offset voltage at the input. The amplifier has a maximum input offset current of ±0.75 nA and a typical offset current drift of ±1.5 pA/°C.

Multiplied by the 100 kΩ resistor, this current contributes a maximum offset voltage of 75 µV and a typical offset voltage drift of 150 nV/°Catthe input. Thus, the offset is unlikely to be more than one LSB, so it can usually be ignored.

If the input signal is DC coupled, only the resistor connecting the negative signal input to ground is needed. This connection does not lower the input impedance of the AI channel.

Common-Mode Signal Rejection Considerations

Figures 3-4 and 3-5 show connections for signal sources that are already referenced to some ground point with respect to the DAQCard-700. In these cases, the instrumentation amplifier can reject any voltage due to ground potential differences between the signal source and the DAQCard-700. In addition, with DIFF input connections, the instrumentation amplifier can reject common-mode noise pickup in the leads connecting the signal sources to the DAQCard-700.

The common-mode input range of the DAQCard-700 instrumentation amplifier is defined as the magnitude of the greatest common-mode signal that can be rejected. The DAQCard-700 can reject common-mode input signalssolongasV

and V

–

are both in the range ±9.5 V.

The common-mode input range for the DAQCard-700 depends on the size

of the differential input signal (V

diff

–

– V

). The formula for the

permissible common-mode input range is as follows:

cm-max

=±(9.5V– V

diff

/2)

Thus, for a differential voltage as large as 10 V, the largest common-mode voltage that can be rejected is ±4.5 V. However, if the differential signal is

2.5 V, ±8.25 V common-mode voltage can be rejected.

DAQCard-700 User Manual 3-12 ni.com

The common-mode voltage is measured with respect to the DAQCard-700 ground and can be calculated by the following formula:

where V

is the signal at the positive input of the instrumentation

amplifier and V amplifier.

If the input signal common-mode range exceeds the maximum value (computed above) with respect to the DAQCard-700 ground, limit the amount of floating that occurs between the signal ground and the DAQCard-700 ground.

Connecting Digital I/O Signals

Pins 22 through 37 of the I/O connector are DIO signal pins. Pins 22 through 29 are digital input pins. Pins 30 through 37 are digital output pins. Pins 19 and 50 are digital ground pins.

Refer to Appendix A, Specifications, for more information about the specifications and ratings for the DIO lines.

Chapter 3 Connecting Signals

cm-actual

–

is the signal at the negative input of the instrumentation

=(V

–

)/2

Figure 3-6 shows an example of connections to the digital input and output ports. Digital input applications include receiving TTL signals and sensing external device states such as the switch in Figure 3-6. Digital output applications include sending TTL signals and driving external devices, such as the LED shown in Figure 3-6.

Chapter 3 Connecting Signals

22 DIN0

+5 V

LED

Connecting Power

TTL Signal

29 DIN7

+5 V

DGND

30 DOUT0

I/O Connector

DAQCard-700

Digital

Input

Por t

Digital

Output

Por t

Figure 3-6. Digital I/O Signal Connections

Pin 49 of the I/O connector sends +5 V from the PCMCIA I/O channel power supply. This pin is referenced to DGND and can be used to power external digital circuitry that draws up to 1 A. Pin 49 is connected to a 1 A resettable fuse on the card. The actual current available from this signal may be less than 1 A, depending on the computer. Notice also that any current drawn from this line adds to the power requirements from the computer.

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Chapter 3 Connecting Signals

Caution

Connections, including power signals to ground and vice versa, that exceed any of the maximum signal ratings on the DAQCard-700 can result in damage to the DAQCard-700 card. NI is not liable for any injuries or damage resulting from incorrect signal connections

Connecting Timers

Pins 38 through 48 of the I/O connector are connections for TIO signals. The DAQCard-700 TIO uses an MSM82C54 counter/timer integrated circuit. All three integrated counter/timers of the MSM82C54 are available at the I/O connector. One of these counters, counter 0, is used for DAQ timing. Pin 40 carries an external signal, EXTCONV*, that can be used for DAQ timing in place of counter 0 of the MSM82C54. This signal is explained in the Data Acquisition Counter and Timing Connections section. Pins 38 and 41 through 48 carry general-purpose timing signals from the MSM82C54. These signals are explained under the

General-Purpose Counter and Timing Signal Connections section.

Data Acquisition Counter and Timing Connections

Counter 0 on the MSM82C54 is used as a sample-interval counter in timed A/D conversions. In addition to counter 0, you can use pin 40, EXTCONV*, to externally time conversions. Figure 3-7 shows the timing requirements for the EXTCONV* input. An A/D conversion is initiated by a rising edge on the EXTCONV*. The data from this conversion is latched into the FIFO memory within 10 µs. The EXTCONV* input is a TTL-compatible signal.

EXTCONV*

int

A/D Conversion Starts Here

Figure 3-7. EXTCONV* Signal Timing

200 ns Minimum

Notice that EXTCONV* only causes conversions to occur; you cannot use it as a monitor to detect conversions caused by the onboard sample-interval timer.

Chapter 3 Connecting Signals

General-Purpose Counter and Timing Signal Connections

The general-purpose timing signals include the GATE, CLK, and OUT signals for the three integrated counter/timers, except CLK of counter 0 is not available on the I/O connector. You can use the counter/timers for general-purpose applications such as pulse and square wave generation, event counting, and pulse-width, time-lapse, and frequency measurement. For these applications, CLK and GATE signals are sent to the counters, and the counters are programmed for various operations. The only exceptions are counter 0, which has an internal 1 MHz clock, and counter 1, which can also be configured to use this clock.

The MSM82C54 is described briefly in the Timing I/O Circuitry section of Chapter 4, Theory of Operation.

To perform pulse and square wave generation, program a counter to generate a timing signal at its OUT output pin.

To count events, program a counter to count rising or falling edges applied to any of the MSM82C54 CLK inputs. You can then read the counter value to determine the number of edges that have occurred. You can gate counter operation on and off during event counting. Figure 3-8 shows connections for a typical event-counting operation in which a switch is used to gate the counter on and off.

DAQCard-700 User Manual 3-16 ni.com

+5 V

Chapter 3 Connecting Signals

CLK

OUT

Signal

Source

Switch

I/O Connector

Use level gating to measure pulse width. Apply the pulse to be measured to the counter GATE input. Load the counter with the known count and program the counter to count down while the signal at the GATE input is high. The pulse width equals the counter difference (loaded value minus read value) multiplied by the CLK period.

To measure time lapse, program a counter to be edge gated. Apply an edge to the counter GATE input to start the counter. Program the counter to start counting after receiving a low-to-high edge. The time lapse since receiving the edge equals the counter value difference (loaded value minus the read value) multiplied by the CLK period.

19 DGND

Figure 3-8.

GATE

Counter

DAQCard-700

Event-Counting Application with External Switch Gating

Chapter 3 Connecting Signals

Signal

Source

To measure frequency, program a counter to be level gated and count the number of falling edges in a signal applied to a CLK input. The gate signal you applied to the counter GATE input is of a known duration. In this case, program the counter to count falling edges at the CLK input while the gate is applied. The frequency of the input signal then equals the count value divided by the gate period. Figure 3-9 shows the connections for a frequency measurement application. You could also use a second counter to generate the gate signal in this application.

+5 V

CLK

OUT

GATE

Gate

Source

Counter

19 DGND

I/O Connector

DAQCard-700

Figure 3-9. Frequency Measurement Application

The GATE, CLK, and OUT signals for counters 1 and 2 are available at the I/O connector. In addition, the GATE and CLK pins are pulled up to +5 V through a 100 kΩ resistor.

DAQCard-700 User Manual 3-18 ni.com

CLK

GATE

Chapter 3 Connecting Signals

Figure 3-10 shows the timing requirements for the GATE and CLK input signals and the timing specifications for the OUT output signals of the MSM82C54.

sc pwh pwl

gsu gh

gwh gwl

OUT

outg

clock period

pwh

clock high level

pwl

clock low level

gsu

gate setup time

gate hold time

gwh

gate high level

gwl

gate low level

outc

output delay from clock

outg

output delay from gate

100 ns min

30 ns min

50 ns min

40 ns min

50 ns min

100 ns max

outc

Figure 3-10. General-Purpose Timing Signals

The GATEand OUT signals in Figure 3-10 are referenced to the rising edge of the CLK signal.

Refer to Appendix A, Specifications, for more information about the MSM82C54 DIO specifications.

Theory of Operation

This chapter includes an overview of the DAQCard-700 and explains the operation of each functional unit making up the DAQCard-700.

Functional Overview

The block diagram in Figure 4-1 shows a functional overview of the DAQCard-700.

Chapter 4 Theory of Operation

Instrumentation

Amplifier

Mux1 Dual

(8-Channel

Scanning

Input

Single-

Ended)

Counter

–

Input Mux2

(4-Channel)

Buffer

12-Bit

Sampling

ADC

512-Word

FIFO

PCMCIA

I/O Channel

Interface

I/O Connector

GATE<0..2>

CLK<1..2>

OUT<0..2>

From A/D FIFO

+12 V

OUT0EXTCONV*

MSM82C54

Digital

I/O

DC-DC

Converter

A/D Timing

To Analog CircuitTo Analog Circuit

1 A Resettable Fuse

Figure 4-1. DAQCard-700 Block Diagram

Interrupt Interface

PCMCIA I/O Channel

+5 V+5 V

The following are the major components making up the DAQCard-700:

• PCMCIA I/O channel interface circuitry

• AI circuitry

DAQCard-700 User Manual 4-2 ni.com

• DIO circuitry

• TIO circuitry

DAQ functions can be executed by using the AI circuitry and some of the TIO circuitry. The internal data and control buses interconnect the components. The theory of operation for each of these components is explained in the remainder of this chapter. The theory of operation for the DAQ circuitry is included with the discussion of the AI circuitry.

PCMCIA I/O Channel Interface Circuitry

The PCMCIA I/O channel interface circuitry consists of an address bus, a data bus, interrupt lines, and several control and support signals. The components making up the DAQCard-700 PCMCIA I/O channel interface circuitry are shown in Figure 4-2.

Address Decoder

Chapter 4 Theory of Operation

Address Bus

Timing

Read and Write Signals

Card

Information

Structure

Internal Data Bus

PCMCIA

Control

Registers

Interrupt Requests

Figure 4-2.

PCMCIA I/O Interface Circuitry Block Diagram

Interface

Data

Buffers

Interrupt

Control

Control Lines

Data Bus

PCMCIA I/O Channel

IRQ

Chapter 4 Theory of Operation

When you first insert the card, the system examines information stored in the DAQCard-700 Card Information Structure (CIS). This data is used to configure the card for the system in which it is used. When the system has assigned the card to a section of memory, it updates the PCMCIA control registers and initializes the card.

The rest of the circuitry consists of address decoders, data buffers, I/O channel interface timing control circuitry, and interrupt control circuitry. The circuitry monitor uses CE1* (controlled by the PCMCIA Card and Socket Services Software) as the card enable signal, and uses lines <A0..A4> plus timing signals to generate the onboard register select signals and read/write signals. The data buffers control the direction of data transfer on the bidirectional data lines based on whether the transfer is a read or write. The interrupt control circuitry routes any enabled interrupts to the IREQ* line, which is routed to an available interrupt request line by the system motherboard. The DAQCard-700 generates interrupts in three different situations:

• When a prescribed number of A/D conversions can be read from FIFO

• When an active low-level signal is detected on the EXTINT* line

• When a rising-edge signal is detected on counter 2 output

Each one of these interrupts is individually enabled and cleared.

Analog Input and Data Acquisition Circuitry

The DAQCard-700 has 16 AI channels with 12-bit A/D conversion. Using the timing circuitry, the DAQCard-700 can automatically time multiple A/D conversions. Figure 4-3 shows a block diagram of the AI and DAQ circuitry.

DAQCard-700 User Manual 4-4 ni.com

Mux1 Dual

(8-Channel

Single-

Ended)

I/O Connector

Scanning

Counter

Input

Instrumentation

Amplifier

Input

Mux2

(4-Channel)

Buffer

12-Bit

Sampling

ADC

A/D Timing

A/D

Data

OUT0

512-Word

FIFO,

Sign

Extension

MSM82C54

Chapter 4 Theory of Operation

1612

PCMCIA

Data

I/O Channel

Interface

A/D RD

Interrupt

Interface

PCMCIA I/O Channel

EXTCONV*

Analog Input Circuitry

The AI circuitry consists of an input multiplexer, a software-selectable gain stage, and a 12-bit sampling ADC. The 12-bit output is sign-extended to 16 bits, then stored in a FIFO memory that is 512 words deep.

The input multiplexer stage is made up of two CMOS AI multiplexers. In single-ended mode, the input multiplexers switch between 16 AI channels (channels 0 through 15). In DIFF input mode, one of the input multiplexers switches between eight differential pairs (channels 0 and 8, 1 and 9, and so on). With the input multiplexer stage, input overvoltage protection of ±30Visavailable,poweredonoroff.

The DAQCard-700 uses a 12-bit successive-approximation ADC. Software-selectable gains of 1, 0.5, and 0.25 for the input signal combined with the ADC fixed input range of ± 10 V yield three useful AI signal ranges. These ranges are ±10 V, ± 5 V, and ± 2.5 V.

When an A/D conversion is complete, the ADC clocks the result into the A/D FIFO. The A/D FIFO is 16 bits wide and 512 words deep. This FIFO

CLK0

1MHz

Figure 4-3. Analog Input and DAQ Circuitry Block Diagram

Chapter 4 Theory of Operation

serves as a buffer to the ADC and has two benefits. First, when an A/D conversion is complete, the value is saved in the A/D FIFO for later reading, and the ADC is free to start a new conversion. Secondly, the A/D FIFO can collect up to 512 A/D conversion values before any information is lost, thus giving the software some extra time (512 times the sample interval) to catch up with the hardware. If more than 512 values are stored in the A/D FIFO without the A/D FIFO being read from, an error condition called A/D FIFO overflow occurs and A/D conversion information is lost.

The A/D FIFO generates a signal that indicates when it contains A/D conversion data. The state of this signal can be read from the Status Register.

The output from the ADC is a two’s complement number ranging from –2,048 to 2,047. The output from the 12-bit ADC is always sign-extended to 16 bits by the card circuitry so that data values read from the FIFO are 16 bits wide.

Data Acquisition Timing Circuitry

A DAQ operation refers to the process of obtaining a series of successive A/D conversions at a carefully timed interval called the sample interval. The DAQ timing circuitry consists of various clocks and timing signals that perform this timing. The DAQCard-700 can perform two types of data acquisition: single-channel data acquisition and multichannel (scanned) data acquisition. Scanned data acquisition uses a counter to automatically switch between AI channels during data acquisition. The scan interval is equal to the number of channels multiplied by the sample interval.

DAQ timing consists of signals that initiate a DAQ operation and generate scanning clocks. Sources for these signals are supplied mainly by timers on the DAQCard-700 card. One of the three counters of the MSM82C54 is reserved for this purpose.

An A/D conversion can be initiated internally during data acquisition by a low-to-high transition on the counter 0 output (OUT0) of the MSM82C54, or externally by a low-to-high transition on EXTCONV* input.

The sample-interval timer is a 16-bit down counter that uses the onboard 1 MHz clock to generate sample intervals from 2 µs to 65,535 µs(Referto the Timing I/O Circuitry section). Each time the sample-interval timer reaches zero, it generates a pulse and reloads with the programmed sample-interval count. This operation continues until the counter is reprogrammed.

DAQCard-700 User Manual 4-6 ni.com

Chapter 4 Theory of Operation

Notice that only counter 0 is required for DAQ operations. The software must track the number of conversions that have occurred and turn off counter 0 after the required number of conversions has been obtained.

Single-Channel Data Acquisition

During single-channel data acquisition, a control register is set to select the analog input channel before data acquisition is initiated. This multiplexer setting remains constant during the entire data acquisition process; therefore, all A/D conversion data is read from a single channel.

Multichannel (Scanned) Data Acquisition

Multichannel data acquisition is performed by enabling scanning during data acquisition. Multichannel scanning is controlled by a scan counter.

For scanning operations, the scan counter decrements from the highest numbered channel(selected by the user) through channel 0 and then repeats the sequence. For RSE input mode, therefore, any number of channels from 2 to 16 can be scanned. For DIFF input mode, any number of channels from 2 to 8 can be scanned. Notice that the same AI range is used for all channels in the scan sequence.

Data Acquisition Rates

The maximum data acquisition rate (number of samples per second) is determined by the conversion period of the ADC plus the acquisition time of its track-and-hold stage. During multichannel scanning, the data acquisition rate is further limited by the settling time of the input multiplexers and operational amplifier. After the input multiplexers are switched, the amplifier must be able to settle to the new input signal value to within 12-bit accuracy before an A/D conversion is performed, or 12-bit accuracy cannot be achieved.

If the chosen data acquisition rate does not allow the specified settling time, the analog input circuitry may not perform at 12-bit accuracy. Furthermore, if the maximum data acquisition rate is exceeded, A/D conversions may be lost. The maximum data acquisition rate and settling time specifications at various input ranges are listed in Appendix A, Specifications.

Chapter 4 Theory of Operation

These settling time specifications assume that voltage levels on all the channels included in the scan sequence are within range and are driven by low-impedance sources. Signal levels outside the ranges on the channels included in the scan sequence adversely affect the input settling time. Similarly, greater settling time may be required for channels driven by high-impedance signal sources.

Digital I/O Circuitry

The DAQCard-700 has 16 TTL-compatible DIO lines. DIN<0..7> are digital input lines, and DOUT<0..7> are digital output lines. These lines are monitored, or driven, by the Digital Input Register and the Digital Output Register, respectively. Reading the Digital Input Register returns the current state of DIN<0..7>. Writing the Digital Output Register drives the new value onto DOUT<0..7>. An external device may drive the EXTINT* signal to indicate readiness for data transfer. Figure 4-4 shows a diagram of this circuitry.

DIN<0..7>

DOUT<0..7>

I/O Connector

EXTINT*

Figure 4-4. Digital I/O Circuitry Block Diagram

DAQCard-700 User Manual 4-8 ni.com

Digital

Input

Digital

Output

Status Register

Interrupt

Interface

I/O RD

I/O WR

PCMCIA I/O Channel

Timing I/O Circuitry

The DAQCard-700 uses an MSM82C54 counter/timer integrated circuit for DAQ timing and general-purpose TIO functions. Three counters of the MSM82C54 are available for general use, but Counter 0 is also used internally for DAQ timing. Figure 4-5 shows a block diagram of both groups of TIO circuitry.

A/D Conversion Logic

Chapter 4 Theory of Operation

OUT0

GATE0

1-MHz

Clock

CLK1

OUT1

I/O Connector

OUT1*

CLK2

GATE2

OUT2

Interrupt

Interface

OUT0

GATE0

CLK0

Input

Mux

CLK1

GATE1

OUT1

CLK2

GATE2

OUT2

MSM82C54 Counter/Timer

CTR RD/WR

PCMCIA I/O Channel

Data

Figure 4-5. Timing I/O Circuitry Block Diagram

Chapter 4 Theory of Operation

The MSM82C54 contains three independent 16-bit counter/timers and one 8-bit mode register. As shown in Figure 4-5, counter 0 can be used for DAQ timing, and counters 1 and 2 are free for general use. Counter 0 is free for general use when EXTCONV* is being used to time the AI circuitry or when the DAQ circuitry is not in use.

The MSM82C54 counter 0 uses a 1 MHz clock generated from the onboard oscillator. The timebases for counters 1 and 2 can be supplied externally through the 50-pin I/O connector. In addition, counter 1 can optionally use the same onboard 1 MHz clock that is used for DAQ timing, which facilitates synchronous operations. The counters in the MSM82C54 can be diagrammed as shown in Figure 4-6.

CLK

Counter

GATE

Figure 4-6. Counter Block Diagram

OUT

Each counter has a clock input pin, a gate input pin, and an output pin labeled CLK, GATE, and OUT, respectively. The MSM82C54 counters are numbered zero through two, and their GATE, CLK, and OUT pins are labeled GATE N,CLKN,andOUTN,whereN is the counter number.

DAQCard-700 User Manual 4-10 ni.com

Specifications

This appendix lists the specifications of the DAQCard-700. These specifications are typical at 25 °C unless otherwise noted. The operating temperature range is 0 to 70 °C.

Analog Input

Input Characteristics

Number of channels ............................... 16 single-ended or 8 differential,

Type of ADC.......................................... Successive approximation

Resolution .............................................. 12 bits, worst-case code range

software-selectable

–2024 to +2023 (due to software calibration)

Max sampling rate.................................. 100 kS/s

Input signal ranges ................................. ±10 V, ±5 V, ±2.5 V;

software-selectable

Input coupling ........................................ DC

Max working voltage

(signal + common mode) ....................... Each input should remain within

±9.5 V of AIGND (in DIFF mode)

Overvoltage protection........................... ±30 V powered on,

± 30 V powered off

Inputs protected...................................... ACH<0..15>

FIFO buffer size ..................................... 512 samples

Data transfers ......................................... Interrupts, programmed I/O

Please refer to the Dynamic Characteristics section for maximum scan rates with stated accuracy.

Appendix A Specifications

Transfer Characteristics

Relative accuracy....................................±1 LSB typ, ±1.5 LSB max

DNL ........................................................±0.5 LSB typ, ±1 LSB max

No missing codes....................................12 bits, guaranteed

Offset error

After software calibration................±1 LSB

Before software calibration .............±2 LSB typ, ±9 LSB max

Gain error (relative to calibration reference)

After software calibration................±0.036% max

Before software calibration .............±0.07% of reading typ,

±0.4% max

Amplifier Characteristics

Input impedance .....................................1 GΩ in parallel with 40 pF

CMRR (all input ranges) ........................–72 dB, DC to 60 Hz

Dynamic Characteristics

Settling time ±0.024% accuracy

(±1 LSB) for full-scale step....................25 µs max at ±10 V, ±5 V

10 µsat±2.5V(RSE)

System noise ...........................................0.5 LSB

at ±5 V range

rms

Stability

Recommended warm-up time.................15 min

Onboard calibration reference

Level................................................3.0 V (±0.2 mV)

Temperature coefficient...................60 ppm/°Cmax

Digital I/O

Number of channels................................8 input and 8 output

Compatibility ..........................................TTL-compatible

DAQCard-700 User Manual A-2 ni.com

Appendix A Specifications

Maximum votage input rating................ +5.5 V with respect to DGND

–5.5 V with respect to DGND

Digital logic levels

Level Min Max

Input low voltage 0V 0.8 V

Input high voltage 2V 5V

Input low current (Vin=0V) — –50 µA

Input high current (Vin=5V) — 1 µA

Timing I/O

Output low voltage (I

Output high voltage (I

=4mA) — 0.4 V

out

=4mA) 3.7 V —

out

Number of channels ............................... 3 counter/timers

(1 dedicated to analog input)

Resolution .............................................. 16 bits

Compatibility ......................................... TTL, gate and source pulled

high with 100 kΩ resistors

Maximum voltage input rating............... –0.5to+5.0Vwithrespectto

DGND

Digital logic levels for MSM82C54

Level Min Max

Input low voltage — +0.8 V

Input high voltage — +2.2 V

Input load current — ±10.0A

Output low voltage — +0.40 V

Output high voltage +3.0 V —

Output source current — ±2.5mA

Output sink current — ±2.5 mA

Appendix A Specifications

Bus Interface

Power Requirement

Note

These power usage figures do not include the power used by external devices that

you have connected to the fused supply present on the I/O connector.

Base clocks available..............................1 MHz

Base clock accuracy................................±0.01%

Max source frequency.............................10 MHz

Min source pulse duration ......................50 ns

Min gate pulse duration ..........................50 ns

Data transfers..........................................Programmed I/O

Type ........................................................slave

+5 VDC (±5%) .......................................100 mA in operational mode

70 mA in power-down mode

Physical

PC Card type...........................................Type II

I/O connector ..........................................50-pin male

Maximum Working Voltage

Maximum working voltage refers to the signal voltage plus the common-mode voltage.

Channel-to-earth .....................................30 VAC or 60 VDC, installation

category I

Channel-to-channel.................................30 VAC or 60 VDC, installation

category I

Environmental

Operating temperature ............................0 to 70 °C

Storage temperature................................–55 to 150 °C

DAQCard-700 User Manual A-4 ni.com

Humidity ................................................ 5 to 90% RH, noncondensing

Maximum altitude ..................................2000 meters

Pollution degree (indoor use only)......... 2

Safety

The DAQCard-700 meets the requirements of the following standards for safety and electrical equipment for measurement, control, and laboratory use:

• EN 61010-1:1993/A2:1995, IEC 61010-1:1990/A2:1995

• UL 3111-1:1994

• CAN/CSA c22.2 no. 1010.1:1992/A2:1997

Electromagnetic Compatibility

CE, C-Tick, and FCC Part 15 (Class A) Compliant

Electrical emissions................................ EN 55011 Class A at 10 m

Appendix A Specifications

FCC Part 15A above 1 GHz

Electrical immunity................................ Evaluated to EN 61326:1997/

A1:1998, Table 1

Note

For full EMC compliance, you must operate this device with shielded cabling. In addition, all covers and filler panels must be installed. Refer to the Declaration of Conformity (DoC) for this product for any additional regulatory compliance information. To obtain the DoC for this product, click Declaration of Conformity at

ni.com/hardref.nsf/

appropriate product family, followed by your product, and a link to the DoC appears in Adobe Acrobat format. Click the Acrobat icon to download or read the DoC.

. This Web site lists the DoCs by product family. Select the

Differences between the PC-LPM-16 and the DAQCard-700

This appendix contains a summary of differences between the PC-LPM-16 and the DAQCard-700 that may be relevant to you if you are a current PC-LPM-16 user.

The DAQCard-700 is compatible with the PC-LPM-16. Software developed for the PC-LPM-16 using NI-DAQ or LabWindows routines, as well as LabVIEW VIs for the PC-LPM-16, typically works with the DAQCard-700 without modification. The following table summarizes the significant differences.

Table B-1. Functionality Differences Between the PC-LPM-16 and the DAQCard-700

Functionality PC-LPM-16 DAQCard-700

FIFO read Two 8-bit words One 16-bit word

FIFO buffer size 16 samples 512 samples

Maximum sample rate 50 kS/s 100 kS/s

Supply voltages at I/O connector +5 V, +12 V, –12 V +5 V

Maximum input voltage rating ±45V ±30V

ADC calibration Hardware calibration Software calibration

Timer chip MSM82C53 MSM82C54*

Maximum timer source frequency 8MHz 10 MHz

Input modes Single ended Single ended or differential

Input ranges ±5 V, ±2.5 V, 0–10 V, 0–5V,

jumper selectable

* The MSM82C54 timer used in the DAQCard-700 is compatible with the MSM82C53.

±10V,±5V,±2.5V, software-selectable

Common Questions

This appendix contains a list of common questions and answers relating to the operation of the DAQCard-700. The questions are grouped according to the type of information requested.

Installing and Configuring the DAQCard-700

Which NI documentation should I read first to get started using NI-DAQ?

Refer to the Configuring the DAQCard-700 section of Chapter 2, Installing

and Configuring the DAQCard-700, for this information.

What version of NI-DAQ must I have to program the DAQCard-700?

The DAQCard-700 is supported by NI-DAQ for Windows versions 6.9.x and earlier. You may also use the DAQCard-700 with NI-DAQ for Mac OS version 6.6.x or version 4.9.4 or earlier.

What is the best way to test the DAQCard without having to program the DAQCard?

If you are using Windows, MAX has a Test Panel option that is available by clicking Devices and Interfaces and then clicking the device. The Test Panels are excellent tools for performing simple functional tests of the DAQCard, such as analog input, digital I/O, and counter/timer tests. If you are using Mac OS, the NI-DAQ Configuration Utility provides the same functionality.

Operating the DAQCard-700

When using the DAQCard in differential analog input mode, I have connected a differential input signal, but my readings are random and drift rapidly. What’swrong?

Check the ground-reference connections. The signal may be referenced to a level that is considered floating with reference to the DAQCard ground reference. Even if you are in DIFF input mode, the signal must still be

Appendix C Common Questions

referenced to the same ground level as the DAQCard reference. There are various methods of achieving the same ground level while maintaining a high CMRR. These methods are outlined in Chapter 3, Connecting Signals.

I want to use NI-DAQ to program the DAQCard-700. How can I determine which NI-DAQ functions support the DAQCard?

If you are using NI-DAQ 6.7 or later, refer to the NI-DAQ Function Reference Help.ClickNI-DAQ Functions»Listed by Hardware Product

for a complete list of functions supported by the DAQCard-700. If you are using NI-DAQ 6.6 or earlier, refer to Appendix C, NI-DAQ Function Support,oftheNI-DAQ Function Reference Manual for PC Compatibles.

I wish to register-level program the DAQCard-700. Where can I find the information that I need to accomplish this task?

Register-level programming is not recommended for most users. Even experienced register-level programmers will find that using the NI-DAQ, LabVIEW, or Measurement Studio ADE is as easy and as flexible as register-level programming and can save weeks of development time. However, if you choose to register-level program, you can download the DAQCard-700 Register-Level Programmer Manual from

ni.com/manuals

DAQCard-700 User Manual C-2 ni.com

Technical Support Resources

Web Support

NI Web support is your first stop for help in solving installation, configuration, and application problems and questions. Online problem-solving and diagnostic resources include frequently asked questions, knowledge bases, product-specific troubleshooting wizards, manuals, drivers, software updates, and more. Web support is available through the Technical Support section of

NI Developer Zone

ni.com

The NI Developer Zone at building measurement and automation systems. At the NI Developer Zone, you can easily access the latest example programs, system configurators, tutorials, technical news, as well as a community of developers ready to share their own techniques.

Customer Education

NI provides a number of alternatives to satisfy your training needs, from self-paced tutorials, videos, and interactive CDs to instructor-led hands-on courses at locations around the world. Visit the Customer Education section of

ni.com

registration.

System Integration

If you have time constraints, limited in-house technical resources, or other dilemmas, you may prefer to employ consulting or system integration services. You can rely on the expertise available through our worldwide network of Alliance Program members. To find out more about our Alliance system integration solutions, visit the System Integration section of

ni.com

ni.com/zone

for online course schedules, syllabi, training centers, and class

is the essential resource for

Appendix D Technical Support Resources

Worldwide Support

NI has offices located around the world to help address your support needs. You can access our branch office Web sites from the Worldwide Offices section of information, support phone numbers, e-mail addresses, and current events.

If you have searched the technical support resources on our Web site and still cannot find the answers you need, contact your local office or NI corporate. Phone numbers for our worldwide offices are listed at the front of this manual.

ni.com

. Branch office Web sites provide up-to-date contact

DAQCard-700 User Manual D-2 ni.com

Glossary

Prefix Meaning Value

p- pico- 10

n- nano- 10

µ- micro- 10

m- milli- 10

k- kilo- 10

M- mega- 10

G- giga- 10

Numbers/Symbols

° degrees

Ω ohms

% percent

–12

–9

– 6

–3

± plus or minus

+5 V +5 VDC source signal

A amperes

AC alternating current

ACH analog input channel signal

ActiveX controls a special form of Automation Object. ActiveX Controls are similar to

Visual Basic custom controls (VBXs), but their architecture is based on OLE; ActiveX Controls can be freely plugged into any OLE-enabled development tool, application, or Web browser

A/D analog-to-digital

ADC A/D converter

Glossary

ADE application development environment such as LabVIEW,

LabWindows/CVI, BridgeVIEW, Visual Basic, C, and C++

AI analog input

AIGND analog input ground signal

ANSI American National Standards Institute

AWG American Wire Gauge

bipolar a signal range that includes both positive and negative values

(for example, –5Vto+5V)

bit one binary digit, either 0 or 1

buffer temporary storage for acquired or generated data (software)

byte eight related bits

CCelsius

CE card enable signal

CIS card information structure

CLK clock input signal

CMOS complementary metallic oxide semiconductor

CMRR common-mode rejection ratio

COM communications port

counter/timer a circuit that counts external pulses or clock pulses (timing)

CPU central processing unit

D/A digital-to-analog

DAQ data acquisition

dB decibel

DAQCard-700 User Manual G-2 ni.com

Glossary

DC direct current

DGND digital ground signal

DIFF differential configuration

DIN digital input signal

DIO digital input/output

DOS disk operating system

DOUT digital output signal

drivers/driver software software that controls a specific hardware device such as a DAQ device

EEPROM erasable programmable read-only memory—ROM that can be erased

(usually by ultraviolet light exposure) and reprogrammed

EXTCONV external control signal to trigger A/D conversions

EXTINT external interrupt signal

Ffarads

FIFO first-in-first-out

ft feet

GATE gate input signal

gh gate hold time

gsu gate setup time

gwh gate high level

gwl gate low level

Hz hertz

Glossary

I/O input/output

in. inches

interrupt a computer signal indicating that the CPU should suspend its current

task to service a designated activity

out

output source current, at V

output sink current, at V

output current

IREQ interrupt request

KB kilobytes

LabVIEW a graphical programming language

LED light-emitting diode

LSB least significant bit

max maximum

MAX Measurement and Automation Explorer—a controlled centralized

configuration environment that allows you to configure your National Instruments DAQ device

MB megabytes of memory

MSB mostsignificantbit

mux multiplexer—a switching device with multiple inputs that sequentially

connects each of its inputs to its output, typically at high speeds, in order to measure several signals with a single analog input channel

DAQCard-700 User Manual G-4 ni.com

Glossary

NC not connected (signal)

NI National Instruments

NI-DAQ National Instruments driver software for DAQ hardware

OUT output signal

outc output delay from clock

outg output delay from gate

PC Card a credit-card-sized expansion card that fits in a PCMCIA slot often

referred to as a PCMCIA card

PCMCIA Personal Computer Memory Card International Association

pwh clock high level

pwl clock low level

RAM random-access memory

RH relative humidity

rms root mean square

ROM read-only memory

RSE referenced single-ended mode—all measurements are made with

respect to a common reference measurement system or a ground; also called a grounded measurement system

S samples

s seconds

Glossary

sample interval amount of time between samples

sc clock period

scan interval the number of channels multiplied by the sample interval

settling time the amount of time required for a voltage to reach its final value within

specified limits

TIO timing input/output

trigger any event that causes or starts some form of data capture

TTL transistor-transistor logic

two’s complement given a number x expressedinbase2withn digits to the left of the radix

point, the (base 2) number 2n - x

unipolar a signal range that is always positive (for example, 0 to +10 V)

V volts

VDC volts, direct current

diff

VI virtual instrument

DAQCard-700 User Manual G-6 ni.com

common-mode noise

differential input signal

volts, input high

volts, input low

volts in

volts, output high

volts, output low

signal source

Index

Symbols

+5 V signal, 3-3

ACH<0..15> signal, 3-2 AIGND signal, 3-2 analog input

specifications, A-1

analog input circuitry

block diagram, 4-5 theory of operation, 4-5

analog input configuration

analog input modes, 2-4 default settings (table), 2-3 DIFF input

configuration, 2-5

definition (table), 2-4 exceeding maximum ratings (caution), 2-3 RSE input

configuration, 2-4

definition (table), 2-4

analog input signal connections

differential (DIFF) connections

common-mode signal rejection

considerations, 3-12 floating signal sources, 3-11 grounded signal sources, 3-10

differential input mode, 3-6 exceeding maximum input rating

(caution), 3-4 floating measurement system, 3-5 floating signal sources, 3-4 ground-referenced measurement

system, 3-5 ground-referenced signal sources, 3-4 input configurations, 3-5

instrumentation amplifier, 3-5 pins for analog input, 3-3 recommended input configurations, 3-7 single-ended connection s, 3-7 single-ended input mode, 3-6 types of measurement systems, 3-4 types of signal sources, 3-4

bus interface, A-4

cabling, 1-4 CLK, OUT, and GATE signals for

general-purpose timing, 3-16 CLK1 signal, 3-3 CLK2 signal, 3-3 common-mode signal rejection

considerations, 3-12 configuration

analog I/O

analog input modes, 2-4 default settings (table), 2-3 DIFF input, 2-5 exceeding maximum ratings

(caution), 2-3

RSE input, 2-4 counter/timers, 2-5 digital I/O, 2-5 input configurations

differential input mode, 3-6

instrumentation amplifier, 3-6

recommended input configurations

(table), 3-7

single-ended input mode, 3-6

Index

PC Card, C-1

typical configuration (figure), 2-2 conventions used in the manual, vii counter/timers

National Instruments DAQCARD-700 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

DAQCard™-700 User Manual

Support

Worldwide Technical Support and Product Information

National Instruments Corporate Headquarters

Worldwide Offices

Important Information

Warranty

Copyright

Trademarks

Patents

WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS

Contents

About This Manual

Conventions

National Instruments Documentation

About the DAQCard-700

What You Need to Get Started

NI-DAQ

Software Programming Choices

National Instruments ADE Software

Custom Cabling

Unpacking

Safety Information

Installing the Software

Installing the Hardware

Figure 2-1. A Typical Configuration for the DAQCard-700

Configuring the DAQCard-700

Configuring Analog Input

Analog Input Mode

Table 2-2. Analog Input Modes for the DAQCard-700

Configuring Digital I/O

Configuring Counters

I/O Connector

Figure 3-1. DAQCard-700 I/O Connector Pin Assignments

Signal Connection Descriptions

Connecting Analog Input Signals

Types of Signal Sources

Measurement System Types

Input Configurations

Recommended Input Configurations

Table 3-1. Recommended Input Configurations for Ground-Referenced and Floating Measurement Systems

Single-Ended Connection Considerations

Figure 3-3. Single-Ended Analog Input Signal Connections

Differential Connection Considerations

Figure 3-4. Differential Input Connections for Grounded Signal Sources

Connecting Digital I/O Signals

Connecting Power

Figure 3-6. Digital I/O Signal Connections

Connecting Timers

Data Acquisition Counter and Timing Connections

Figure 3-7. EXTCONV* Signal Timing

General-Purpose Counter and Timing Signal Connections

Figure 3-9. Frequency Measurement Application

Figure 3-10. General-Purpose Timing Signals

Functional Overview

Figure 4-1. DAQCard-700 Block Diagram

PCMCIA I/O Channel Interface Circuitry

Analog Input and Data Acquisition Circuitry

Analog Input Circuitry

Figure 4-3. Analog Input and DAQ Circuitry Block Diagram

Data Acquisition Timing Circuitry

Single-Channel Data Acquisition

Multichannel (Scanned) Data Acquisition

Data Acquisition Rates

Digital I/O Circuitry

Figure 4-4. Digital I/O Circuitry Block Diagram

Timing I/O Circuitry

Figure 4-5. Timing I/O Circuitry Block Diagram

Figure 4-6. Counter Block Diagram

Table B-1. Functionality Differences Between the PC-LPM-16 and the DAQCard-700

Glossary

Numbers/Symbols

Index

Symbols