National Instruments NI 6115, NI 6120 User Manual

DAQ

NI 6115/6120 User Manual

Multifunction I/O Devices for
PCI/PXI/CompactPCI Bus Computers

NI 6115/6120 User Manual

August 2002 Edition

Part Number 322812B-01

Support

Worldwide Technical Support and Product Information

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For further support information, see the Technical Support and Professional Services appendix. To comment on
the documentation, send email to [e-mail].

© 2001–2002 National Instruments Corporation. All rights reserved.

Important Information

Warranty

The NI PCI-6115, NI PXI-6115, NI PCI-6120, and NI PXI-6120 devices are 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.

E

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. CUSTOMER’S RIGHT TO RECOVER DAMAGES CAUSED BY FAULT OR NEGLIGENCE ON THE PART OF

N

ATIONAL INSTRUMENTS SHALL BE LIMITED TO THE AMOUNT THERETOFORE PAID BY THE CUSTO MER. NATIONAL INSTRUMENTS WILL NOT BE LIA BLE FOR
DAMAGES RESULTIN G FROM LOSS OF DATA, PROFITS, USE OF PRODUCTS, OR INCIDENTAL OR CONSEQUENTIAL DAMAGES, EVEN IF ADVISED OF THE POSSIBILITY
THEREOF. This limitation of the liability of National Instruments will apply regardless of the form of action, whether in contract or tort, including

negligence. Any action against National Instruments must be brought within one year after the cause of action accrues. National Instruments
shall not be liable for any delay in performance due to causes beyond its reasonable control. The warranty provided herein does not cover
damages, defects, malfunctions, or service failures caused by owner’s failure to follow the National Instruments installation, operation, or
maintenance instructions; owner’s modification of the product; owner’s abuse, misuse, or negligent acts; and power failure or surges, fire,
flood, accident, actions of third parties, or other events outside reasonable control.

Copyright

Under the copyright laws, this publication may not be reproduced or transmitted in any form, electronic or mechanical, 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

CVI™, DAQ-STC™, LabVIEW™, Measurement Studio™, MITE™, MXI™, National Instruments™, NI™, ni.com™, NI-DAQ™, NI Developer

™

, and RTSI™ are trademarks of National Instruments Corporation.

Zone

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 patents.txt file
on your CD, or

ni.com/paten ts.

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 COMPONENT S 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 FIT NESS, 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.

Compliance

FCC/Canada Radio Frequency Interference Compliance

Determining FCC Class

The Federal Communications Commission (FCC) has rules to protect wireless communications from interference. The FCC
places digital electronics into two classes. These classes are known as Class A (for use in industrial-commercial locations only)
or Class B (for use in residential or commercial locations). Depending on where it is operated, this product could be subject to
restrictions in the FCC rules. (In Canada, the Department of Communications (DOC), of Industry Canada, regulates wireless
interference in much the same way.)

Digital electronics emit weak signals during normal operation that can affect radio, television, or other wireless products. By
examining the product you purchased, you can determine the FCC Class and therefore which of the two FCC/DOC Warnings
apply in the following sections. (Some products may not be labeled at all for FCC; if so, the reader should then assume these are
Class A devices.)

FCC Class A products only display a simple warning statement of one paragraph in length regarding interference and undesired
operation. Most of our products are FCC Class A. The FCC rules have restrictions regarding the locations where FCC Class A
products can be operated.

FCC Class B products display either a FCC ID code, starting with the letters EXN,
or the FCC Class B compliance mark that appears as shown here on the right.

Consult the FCC Web site at

FCC/DOC Warnings

This equipment generates and uses radio frequency energy and, if not installed and used in strict accordance with the instructions
in this manual and the CE Mark Declaration of Conformity*, may cause interference to radio and television reception.
Classification requirements are the same for the Federal Communications Commission (FCC) and the Canadian Department
of Communications (DOC).

Changes or modifications not expressly approved by National Instruments could void the user’s authority to operate the
equipment under the FCC Rules.

http://www.fcc.gov for more information.

Class A

Federal Communications Commission

This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to part 15 of the FCC
Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated
in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and
used in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this
equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct
the interference at his own expense.

Canadian Department of Communications

This Class A digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations.

Cet appareil numérique de la classe A respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.

Class B

Federal Communications Commission

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the
FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation.
This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the
instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not
occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can
be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of
the following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and receiver.

• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.

• Consult the dealer or an experienced radio/TV technician for help.

Canadian Department of Communications

This Class B digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations.

Cet appareil numérique de la classe B respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.

Compliance to EU Directives

Readers in the European Union (EU) must refer to the Manufacturer’s Declaration of Conformity (DoC) for information*
pertaining to the CE Mark compliance scheme. The Manufacturer includes a DoC for most every hardware product except for
those bought for OEMs, if also available from an original manufacturer that also markets in the EU, or where compliance is not
required as for electrically benign apparatus or cables.

To obtain the DoC for this product, click Declaration of Conformity at
by product family. Select the 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.

* The CE Mark Declaration of Conformity will contain important supplementary information and instructions for the user or

installer.

ni.com/hardref.nsf/. This Web site lists the DoCs

Contents

About This Manual

Conventions ...................................................................................................................xi

National Instruments Documentation ............................................................................xii

Related Documentation..................................................................................................xiii

Chapter 1
Introduction

About the NI 6115/6120 ...............................................................................................1-1

Using PXI with CompactPCI.........................................................................................1-2

What You Need to Get Started ......................................................................................1-3

Software Programming Choices ....................................................................................1-4

NI-DAQ...........................................................................................................1-4

National Instruments ADE Software...............................................................1-5

Optional Equipment.......................................................................................................1-6

Custom Cabling .............................................................................................................1-6

Unpacking......................................................................................................................1-7

Safety Information .........................................................................................................1-8

Chapter 2
Installing and Configuring the NI 6115/6120

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

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

Configuring the Device..................................................................................................2-3

Chapter 3
Hardware Overview

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

Input Mode ......................................................................................................3-2

Input Polarity and Input Range........................................................................3-3

Considerations for Selecting Input Ranges.......................................3-4

Input Coupling.................................................................................................3-4

Analog Output................................................................................................................3-5

Analog Trigger...............................................................................................................3-5

Antialiasing Filters.........................................................................................................3-8

Phase-Locked Loop Circuit ...........................................................................................3-9

Correlated Digital I/O ....................................................................................................3-10

© National Instruments Corporation vii NI 6115/6120 User Manual

Contents

Timing Signal Routing .................................................................................................. 3-10

Programmable Function Inputs....................................................................... 3-12

Device and RTSI Clocks................................................................................. 3-12

RTSI Triggers ................................................................................................. 3-12

Chapter 4
Connecting Signals

I/O Connector ................................................................................................................ 4-1

I/O Connector Signal Descriptions .................................................................4-3

Types of Signal Sources................................................................................................ 4-7

Floating Signal Sources .................................................................................. 4-7

Ground-Referenced Signal Sources................................................................ 4-8

Connecting Analog Input Signals.................................................................................. 4-8

Connections for Ground-Referenced Signal Sources ..................................... 4-9

Connections for Nonreferenced or Floating Signal Sources........................... 4-11

Common-Mode Signal Rejection Considerations........................................... 4-12

Working Voltage Range................................................................................................ 4-13

Connecting Analog Output Signals............................................................................... 4-14

Connecting Digital I/O Signals ..................................................................................... 4-15

Correlating DIO Signal Connections............................................................................. 4-16

Power Connections........................................................................................................4-18

Connecting Timing Signals ........................................................................................... 4-18

Programmable Function Input Connections ................................................... 4-20

DAQ Timing Connections .............................................................................. 4-20

Waveform Generation Timing Connections................................................... 4-29

General-Purpose Timing Signal Connections................................................. 4-32

TRIG1 Signal.................................................................................... 4-21

TRIG2 Signal.................................................................................... 4-22

STARTSCAN Signal........................................................................ 4-24

CONVERT* Signal .......................................................................... 4-26

AIGATE Signal ................................................................................ 4-27

SISOURCE Signal............................................................................ 4-27

SCANCLK Signal ............................................................................ 4-28

EXTSTROBE* Signal...................................................................... 4-29

WFTRIG Signal................................................................................ 4-29

UPDATE* Signal ............................................................................. 4-30

UISOURCE Signal ........................................................................... 4-31

GPCTR0_SOURCE Signal .............................................................. 4-32

GPCTR0_GATE Signal ................................................................... 4-33

GPCTR0_OUT Signal...................................................................... 4-34

GPCTR0_UP_DOWN Signal........................................................... 4-35

GPCTR1_SOURCE Signal .............................................................. 4-35

GPCTR1_GATE Signal ................................................................... 4-36

NI 6115/6120 User Manual viii ni.com

GPCTR1_OUT Signal ......................................................................4-36

GPCTR1_UP_DOWN Signal ...........................................................4-37

FREQ_OUT Signal ...........................................................................4-38

Field Wiring Considerations..........................................................................................4-39

Chapter 5
Calibration

Loading Stored Calibration Constants...........................................................................5-1

Self-Calibration..............................................................................................................5-2

External Calibration.......................................................................................................5-2

Appendix A
Specifications

Appendix B
Common Questions

Appendix C
Technical Support and Professional Services

Contents

Glossary

Index

© National Instruments Corporation ix NI 6115/6120 User Manual

About This Manual

This manual describes the electrical and mechanical aspects of the
NI 6115/6120 and contains information concerning its operation
and programming.

The NI 6115/6120 family includes the following devices:

• NI PCI-6115

• NI PXI-6115

• NI PCI-6120

• NI PXI-6120

The NI 6115/6120 is a high-performance multifunction analog, digital, and
timing I/O data acquisition (DAQ) device for PXI and PCI bus computers.
Supported functions include analog input (AI), analog output (AO),
digital I/O (DIO), and timing I/O (TIO).

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,
DIO<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.

♦ The ♦ symbol indicates that the following text applies only to a specific

product, a specific operating system, or a specific software version.

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.

© National Instruments Corporation xi NI 6115/6120 User Manual

About This Manual

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 and hardware labels.

CompactPCI CompactPCI refers to the core specification defined by the PCI Industrial

Computer Manufacturer’s Group (PICMG).

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 Monospace text 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.

NI 6115/6120 This phrase refers to any device in the NI 6115/6120 family.

PCI Peripheral Component Interconnect—PCI is a high-performance

expansion bus architecture originally developed by Intel to replace ISA
and EISA.

Platform Text in this font denotes a specific platform and indicates that the text

following it applies only to that platform.

PXI A rugged, open system for modular instrumentation based on CompactPCI,

with special mechanical, electrical, and software features. The PXI bus
standard was originally developed by National Instruments in 1997, and is
now managed by the PXI bus Systems Alliance.

National Instruments Documentation

The NI 6115/6120 User Manual is one piece of the documentation set for
the DAQ system. You could have any of several types of documentation
depending on the hardware and software in the system. Use the
documentation you have as follows:

• DAQ Quick Start Guide—This guide describes how to install the DAQ
software and hardware, and confirm that the DAQ device is operating
properly. When using this guide, refer to the pinout diagram for the
NI 6110/6111. The pinouts for the NI 6110/6111 and the NI 6115/6120
are identical.

NI 6115/6120 User Manual xii ni.com

• DAQ 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. NI application software includes
LabVIEW and Measurement Studio. After you set up the hardware
system, use either your application software documentation or the
NI-DAQ documentation to help you write your application. 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 terminal block and cable assembly installation
guides. They explain how to physically connect the relevant pieces
of the system. Consult these guides when you are making the
connections.

Related Documentation

The following documents contain information you may find helpful:

• DAQ Quick Start Guide, located at

• DAQ-STC Technical Reference Manual, located at ni.com/manuals

• NI Developer Zone tutorial, Field Wiring and Noise Considerations
for Analog Signals, located at

• NI-DAQ User Manual for PC Compatibles, located at

ni.com/manuals

• NI-DAQ Function Reference Help. You can access this help file by
clicking Start»Programs»National Instruments»NI-DAQ»
NI-DAQ Help.

• PCI Local Bus Specification Revision 2.2

• PICMG 2.0 R3.0, CompactPCI Core Specification

• PXI Specification Revision 2.0, available from

About This Manual

ni.com/manuals

ni.com/zone

www.pxisa.org

© National Instruments Corporation xiii NI 6115/6120 User Manual

Introduction

This chapter describes the NI 6115/6120, lists what you need to get started,
describes the optional software and optional equipment, and explains how
to unpack the device.

About the NI 6115/6120

Thank you for buying an NI 6115/6120. The NI 6115/6120 is a Plug and
Play multifunction analog, digital, and timing I/O device for PXI and PCI
bus computers. The NI 6115 features a 12-bit A/D converter (ADC) per
channel with four simultaneously sampling analog inputs, and two 12-bit
D/A converters (DACs) with voltage outputs. The NI 6120 features a 16-bit
ADC per input channel and 16-bit DACs for output. Each device features
eight lines of TTL-compatible correlated DIO, and two 24-bit
counter/timers for TIO.

The NI 6115/6120 is a DAQ device for PXI or the PCI bus. The device
is software configured and calibrated, and completely switchless and
jumperless. This feature is made possible by the NI MITE bus interface
chip that connects the device to the PXI or PCI I/O bus. The MITE
implements the PCI Local Bus Specification so that you can configure
all the interrupts and base memory addresses with software.

1

The NI 6115/6120 uses the NI data acquisition system timing controller
(DAQ-STC) for time-related functions. The DAQ-STC consists of three
timing groups that control AI, AO, and general-purpose counter/timer
functions. These groups include a total of seven 24-bit and three 16-bit
counters and a maximum timing resolution of 50 ns. The DAQ-STC makes
possible such applications as buffered pulse generation and equivalent time
sampling.

The NI 6115/6120 uses the Real-Time System Integration (RTSI) bus to
easily synchronize several measurement devices to a common trigger or
timing event. The RTSI bus allows synchronization of the measurements.
The RTSI bus consists of the RTSI bus interface and a ribbon cable to route
timing and trigger signals between as many as five DAQ devices in the
computer. If you are using the NI PXI-6115/6120 in a PXI chassis, RTSI
lines, known as the PXI trigger bus, are part of the backplane. Therefore,

© National Instruments Corporation 1-1 NI 6115/6120 User Manual

Chapter 1 Introduction

you do not need the RTSI cable for system triggering and timing on the
PXI. In addition, a phase-locked loop (PLL) circuit accomplishes the
synchronization of multiple NI PXI-6115/6120 devices or other PXI
devices which support PLL synchronization by allowing these devices to
all lock to the same reference clock present on the PXI backplane. Refer to
the Phase-Locked Loop Circuit section of Chapter 3, Hardware Overview,
for more information.

Detailed specifications of the NI 6115/6120 are in Appendix A,

Specifications.

Using PXI with CompactPCI

The ability to use PXI-compatible products with standard CompactPCI
products is an important feature of PXI Specification Revision 2.0. If you
use a PXI-compatible plug-in device in a standard CompactPCI chassis,
you are unable to use PXI-specific functions, but you can still use the basic
plug-in device functions. For example, the RTSI interface on the
NI PXI-6115/6120 is available in a PXI chassis, but not in a CompactPCI
chassis.

The CompactPCI specification permits vendors to develop sub-buses that
coexist with the basic PCI interface on the CompactPCI bus. Compatible
operation is not guaranteed between CompactPCI devices with different
sub-buses nor between CompactPCI devices with sub-buses and PXI
devices. The standard implementation for CompactPCI does not include
these sub-buses. The NI PXI-6115/6120 works in any standard
CompactPCI chassis adhering to PICMG CompactPCI 2.0 R3.0.

PXI-specific features are implemented on the J2 connector of the
CompactPCI bus. Table 1-1 lists the J2 pins used by the NI PXI-6115/6120.
The PXI device is compatible with any CompactPCI chassis with a sub-bus
that does not drive these lines. Even if the sub-bus is capable of driving
these lines, the PXI device is still compatible as long as those pins on the
sub-bus are disabled by default and are never enabled.

Caution Damage can result if these lines are driven by the sub-bus.

NI 6115/6120 User Manual 1-2 ni.com

Table 1-1. NI PXI-6115/6120 J2 Pin Assignment

NI PXI-6115/6120 Signal PXI Pin Name

RTSI<0..5> PXI Trigger<0..5> B16, A16, A17,

RTSI 6 Star D17

RTSI Clock PXI Trigger 7 E16

Reserved LBL<0..12> C20, E20, A19,

Reserved LBR<0..12> A21, C21, D21,

What You Need to Get Started

To set up and use the NI 6115/6120, you need the following:

Chapter 1 Introduction

PXI J2 Pin

Number

A18, B18, C18

C19

E21, A20, B20,
E15, A3, C3, D3,
E3, A2, B2

❑ A computer or a PXI/CompactPCI chassis and controller

(hereafter referred to as the computer)

❑ At least one of the following devices:

– NI PCI-6115

– NI PXI-6115

– NI PCI-6120

– NI PXI-6120

❑ NI 6115/6120 User Manual

❑ NI-DAQ for PC compatibles

❑ (Optional) One of the following software packages and

documentation:

– LabVIEW (Windows)

– Measurement Studio (Windows)

– VI Logger (Windows)

© National Instruments Corporation 1-3 NI 6115/6120 User Manual

Chapter 1 Introduction

Software Programming Choices

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

NI-DAQ

NI-DAQ, which shipped with the NI 6115/6120, has an extensive library of
functions that you can call from the ADE. These functions allow you to use
all the features of the device.

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 the code. Whether you are using LabVIEW, LabWindows
Measurement Studio, VI Logger, or other ADEs, your application uses
NI-DAQ, as illustrated in Figure 1-1.

™

/CVI™,

NI 6115/6120 User Manual 1-4 ni.com

Chapter 1 Introduction

Conventional

Programming Environment

NI-DAQ

Driver Software

DAQ

Hardware

Figure 1-1. The Relationship Among the Programming Environment,

NI-DAQ, and the Hardware

LabVIEW,

LabWindows/CVI,

Measurement Studio,

or VI Logger

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 for using LabVIEW
with National Instruments DAQ hardware, is included with LabVIEW.

LabWindows/CVI is a complete ANSI C ADE that features an interactive
user interface, code generation tools, and the LabWindows/CVI Data
Acquisition and Easy I/O libraries.

Measurement Studio, which includes tools for Visual C++ and tools for
Visual Basic, is a development suite that allows you to design test and
measurement applications. For Visual Basic developers, Measurement
Studio features a set of ActiveX controls for using National Instruments

© National Instruments Corporation 1-5 NI 6115/6120 User Manual

Chapter 1 Introduction

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

VI Logger is an easy-to-use yet flexible tool specifically designed for data
logging applications. Using dialog windows, you can configure data
logging tasks to easily acquire, log, view, and share your data. VI Logger
does not require any programming; it is a stand-alone, configuration-based
software program.

Using LabVIEW, LabWindows/CVI, Measurement Studio, or VI Logger
greatly reduces the development time for your data acquisition and control
application.

Optional Equipment

NI offers a variety of products to use with the NI 6115/6120, including
cables, connector blocks, and other accessories, as follows:

• Shielded cables and cable assemblies

• Connector blocks, shielded 50- and 68-pin screw terminals

• RTSI bus cables (PCI only)

• Low channel-count signal conditioning modules, devices, and
accessories, including conditioning for strain gauges, resistance
temperature detectors, and relays

For more specific information about these products, refer to the NI catalog
at

ni.com/catalog.

Custom Cabling

NI offers cables and accessories to help you prototype your application or
to use if you frequently change device interconnections.

If you want to develop your own cable, however, adhere to the following
guidelines for best results:

• For AI signals, use shielded twisted-pair wires for each AI pair for
differential inputs. Tie the shield for each signal pair to the ground
reference at the source.

NI 6115/6120 User Manual 1-6 ni.com

Unpacking

Caution Never touch the exposed pins of connectors.

Chapter 1 Introduction

• Route the analog lines separately from the digital lines.

• When using a cable shield, use separate shields for the analog and
digital halves of the cable. Failure to do so results in noise coupling
into the analog signals from transient digital signals.

Mating connectors and a backshell kit for making custom 68-pin cables are
available from NI.

The parts in the following list are recommended for connectors that mate to
the I/O connector on the device:

• Honda 68-position, solder cup, female connector

• Honda backshell

The NI 6115/6120 is shipped in an antistatic package to prevent
electrostatic damage to the device. Electrostatic discharge (ESD) can
damage several components on the device.

To avoid such damage when handling the device, take the following
precautions:

• Ground yourself using a grounding strap or by holding a grounded
object.

• Touch the antistatic package to a metal part of the computer chassis
before removing the device from the package.

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

Store the NI 6115/6120 in the antistatic envelope when not in use.

© National Instruments Corporation 1-7 NI 6115/6120 User Manual

Chapter 1 Introduction

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 National Instruments 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.

• 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.

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.

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

NI 6115/6120 User Manual 1-8 ni.com

Chapter 1 Introduction

The following is a description of installation categories:

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

1

. 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, 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 Installation Category IV are electric meters, and
measurements on primary overcurrent protection devices and
ripple-control units.

1

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.

© National Instruments Corporation 1-9 NI 6115/6120 User Manual

Chapter 1 Introduction

Below is a diagram of a sample installation.

NI 6115/6120 User Manual 1-10 ni.com

Installing and Configuring the
NI 6115/6120

This chapter explains how to install and configure the NI 6115/6120.

Installing the Software

Before you install the NI 6115/6120, complete the following steps to install
the software:

1. Install the ADE, such as LabVIEW or Measurement Studio, according
to the instructions on the CD and the release notes.

2. Install NI-DAQ according to the instructions on the CD and the

DAQ Quick Start Guide included with the device. When using the
DAQ Quick Start Guide, refer to the pinout for the NI 6110/6111,

which is identical to the pinout for the NI 6115/6120.

Note It is important to install NI-DAQ before installing the NI 6115/6120 to ensure that

the device is properly detected.

2

Installing the Hardware

You can install the NI 6115/6120 in any available expansion slot in the
computer. However, to achieve best noise performance, leave as much
room as possible between the NI 6115/6120 and other devices and
hardware.

The following are general installation instructions, so consult the computer
user manual or technical reference manual for specific instructions and
warnings.

♦ NI PXI-6115/6120

1. Power off and unplug the computer.

2. Choose an unused PXI slot in the system. For maximum performance,
the NI PXI-6115/6120 has an onboard DMA controller that you can
use only if the device is installed in a slot that supports bus arbitration,

© National Instruments Corporation 2-1 NI 6115/6120 User Manual

Chapter 2 Installing and Configuring the NI 6115/6120

or bus master devices. NI recommends installing the
NI PXI-6115/6120 in such a slot.

Note The PXI specification requires all slots to support bus master devices, but the

CompactPCI specification does not. If you install in a CompactPCI non-master slot, you
must disable the onboard DMA controller using software.

3. Make sure there are no lighted LEDs on the chassis. If any are lit, wait
until they go out before continuing the installation.

4. Remove the filler panel for the slot you have chosen.

5. Ground yourself using a grounding strap or by touching a grounded
object. Follow the ESD protection precautions described in the

Unpacking section of Chapter 1, Introduction.

6. Remove the rubber front panel screw protectors.

7. Insert the NI PXI-6115/6120 into a 5 V PXI slot. Use the
injector/ejector handle to fully insert the device into the chassis.

8. Screw the front panel of the NI PXI-6115/6120 to the front
panel-mounting rail of the system.

9. Visually verify the installation. Make sure the device is not touching
other devices or components and is fully inserted in the slot.

10. Plug in and power on the computer.

The NI PXI-6115/6120 is now installed. You are now ready to configure
the hardware and software.

♦ NI PCI-6115/6120

1. Power off and unplug the computer.

2. Remove the cover.

3. Make sure there are no lighted LEDs on the motherboard. If any are lit,
wait until they go out before continuing the installation.

4. Remove the expansion slot cover on the back panel of the computer.

5. Ground yourself using a grounding strap or by touching a grounded
object. Follow the ESD protection precautions described in the

Unpacking section of Chapter 1, Introduction.

6. Insert the NI PCI-6115/6120 into a PCI system slot. Gently rock the
device to ease it into place. It may be a tight fit, but do not force the
device into place.

7. Screw the mounting bracket of the device to the back panel rail of the
computer.

NI 6115/6120 User Manual 2-2 ni.com

8. Replace the cover.

9. Plug in and power on the computer.

The NI PCI-6115/6120 is now installed. You are now ready to configure the
hardware and software.

Configuring the Device

Because of the NI standard architecture for data acquisition and the PCI bus
specification, the NI 6115/6120 is completely software-configurable. Two
types of configuration are performed on the NI 6115/6120: bus-related and
data acquisition-related configuration.

The NI PCI-6115/6120 is fully compatible with the industry-standard
PCI Local Bus Specification Revision 2.2. This compatibility allows the
PCI system to automatically perform all bus-related configurations with no
user interaction. Bus-related configuration includes setting the device base
memory address and interrupt channel.

The NI PXI-6115/6120 is fully compatible with the industry-standard PXI
Specification Revision 2.0. This allows the PXI/CompactPCI system to
automatically perform all bus-related configurations with no user
interaction. Bus-related configuration includes setting the device base
memory address and interrupt channel.

Chapter 2 Installing and Configuring the NI 6115/6120

Data acquisition-related configuration, which you must perform, includes
such settings as analog input coupling and range, and others. 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 either the DAQ Quick Start Guide or to the NI-DAQ User Manual
for PC Compatibles at
installation and troubleshooting instructions, refer to

ni.com/support/daq.

© National Instruments Corporation 2-3 NI 6115/6120 User Manual

ni.com/manuals. For operating system-specific

Hardware Overview

This chapter presents an overview of the hardware functions on the
NI 6115/6120. Figures 3-1 and 3-2 provide block diagrams for the NI 6115
and NI 6120, respectively.

3

CH0+

AI CH0

Mux

CH0–

CH1+

AI CH1

Mux

CH1–

CH2+

AI CH2

Mux

CH2–

CH3+

AI CH3

Mux

CH3–

Calibration

Mux

Trigger

Trigger Level

DACs

Digital I/O (8)

PFI / Trigger

Timing

DIO
MUX

DAC0

DAC1

I/O Connector

+

CH0
Amplifier
–

+

CH1
Amplifier
–

+

CH2
Amplifier
–

+

CH3
Amplifier
–

2

STC Digital I/O (8)

FPGA Digital I/O (8)

Data (12)

Calibration

Analog
Trigger

Circuitry

DACs

Anti-

Aliasing

Filter

Anti-

Aliasing

Filter

Anti-

Aliasing

Filter

Anti-

Aliasing

Filter

DAC

FIFO

Trigger

Counter/

Timing I/O

Digital I/O

CH0

12-Bit

ADC

CH1

12-Bit

ADC

CH2

12-Bit

ADC

CH3

12-Bit

ADC

Analog Input

Timing/Control

DAQ - STC

Analog Output
Timing/Control

AO Control

Data (32)

CH0

12

12

12

12

Latch

CH1

Latch

CH2

Latch

CH3

Latch

Data (16)

Data (16)

Data (16)

Data (16)

AI Control

DMA/IRQ

Bus

Interface

RTSI Bus

Interface

IRQ
DMA

ADC
FIFO

Data (32)

Analog

Input

Control

DAQ-STC

Bus

Interface

Analog
Output
Control

Generic

Bus

Interface

EEPROM

EEPROM

Control

FPGA

Control

Control

PCI

Mini

Bus

MITE

Interface

Address/Data

DMA

Interface

DIO

FIFO

I/O

DIO

Bus

Interface

PXI/PCI Bus

RTSI Bus

Figure 3-1. NI 6115 Block Diagram

© National Instruments Corporation 3-1 NI 6115/6120 User Manual

Chapter 3 Hardware Overview

CH0+

AI CH0

Mux

CH0–

CH1+

AI CH1

Mux

CH1–

CH2+

AI CH2

Mux

CH2–

CH3+

AI CH3

Mux

CH3–

Calibration

Mux

Trigger

Trigger Level

DACs

Digital I/O (8)

PFI / Trigger

Timing

DIO

MUX

DAC0

DAC1

I/O Connector

+

CH0
Amplifier

–

+

CH1
Amplifier

–

+

CH2
Amplifier

–

+

CH3
Amplifier

–

2

STC Digital I/O (8)

FPGA Digital I/O (8)

Data (16)

Calibration

Analog
Trigger

Circuitry

DACs

Anti-

Aliasing

Filter

Anti-

Aliasing

Filter

Anti-

Aliasing

Filter

Anti-

Aliasing

Filter

DAC
FIFO

Trigger

Counter/

Timing I/O

Digital I/O

CH0

16-Bit

ADC

CH1

16-Bit

ADC

CH2

16-Bit

ADC

CH3

16-Bit

ADC

Analog Input

Timing/Control

DAQ - STC

Analog Output
Timing/Control

AO Control

Data (32)

16

CH0

Data (16)

Latch

CH1

16

16

16

Latch

CH2

Latch

CH3

Latch

Data (16)

Data (16)

Data (16)

AI Control

IRQ

ADC
FIFO

Data (32)

Generic

Bus

Interface

EEPROM

Mini

MITE

PCI
Bus

Interface

Control

Address/Data

DMA

DMA/IRQ

Bus

Interface

RTSI Bus

Interface

Analog

Input

Control

DAQ-STC

Bus

Interface

Analog
Output

Control

EEPROM

Control

FPGA

DIO

Control

DMA

Interface

DIO

FIFO

I/O

Bus

Interface

PXI/PCI Bus

RTSI Bus

Figure 3-2. NI 6120 Block Diagram

Analog Input

The following sections describe in detail each AI category.

Input Mode

The NI 6115/6120 supports only differential (DIFF) input mode. For more
information about DIFF input, refer to the Connecting Analog Input

Signals section of Chapter 4, Connecting Signals, which contains diagrams

showing the signal paths for DIFF input mode.

Note The inputs are differential only in the sense that the ground loops are broken.

The negative input is not intended to carry signals of interest, rather it provides a DC
reference point for the positive input, which may be different than ground.

NI 6115/6120 User Manual 3-2 ni.com

Input Polarity and Input Range

The NI 6115/6120 has bipolar inputs only. Bipolar input means that the
midpoint of the input voltage range is centered at zero volts.

You can independently configure each channel for a different input voltage
range.

The software-programmable gain on this device increases its overall
flexibility by matching the input signal ranges to those that the ADC can
accommodate. It has ranges of ±42 V, ±20 V, ±10 V, ±5 V, ±2 V, ±1 V,
±500 mV, and ±200 mV and is suited for a wide variety of signal levels.
By choosing the optimal gain setting, you can maximize usage of the
dynamic range of the ADC, which effectively increases input signal
resolution. Table 3-1 shows the overall input range and precision according
to the gain used.

Caution The NI 6115/6120 is not designed for input voltages greater than ±42 VDC.

Input voltages greater than ±42 VDC can damage the NI 6115/6120, any device connected
to it, and the host computer. Overvoltage can also cause an electric shock hazard for the
operator. NI is not liable for damage or injury resulting from such misuse.

Chapter 3 Hardware Overview

© National Instruments Corporation 3-3 NI 6115/6120 User Manual

Chapter 3 Hardware Overview

Table 3-1. Input Range and Measurement Precision

Precision

Input Range

–50 to +50 V

2

–20 to +20 V
–10 to +10 V

–5 to +5 V
–2 to +2 V

–1 to +1V
–500 to +500 mV
–200 to +200 mV

1

The value of 1 least significant bit (LSB) of the ADC; that is, the voltage increment

corresponding to a change of one count in the ADC count.

2

Do not exceed ±42 VDC maximum.

Note: Refer to Appendix A, Specifications, for absolute maximum ratings.

6115 (12-Bit) 6120 (16-Bit)

24.4 mV

9.77 mV

4.88 mV

2.44 mV

977 µV
488 µV
244 µV

97.7 µV

1

1.53 mV

610 µV
305 µV
153 µV

61.0 µV

30.5 µV

15.3 µV

6.10 µV

Considerations for Selecting Input Ranges

The range you select depends on the expected range of the incoming signal.
A large input range can accommodate a large signal variation but reduces
the voltage resolution. Choosing a smaller input range improves the voltage
resolution but may result in the input signal going out of range. For best
results, match the input range as closely as possible to the expected range
of the input signal.

Input Coupling

You can configure the NI 6115/6120 for either AC or DC input coupling
on a per channel basis. Use AC coupling when the AC signal contains a
large DC component. If you enable AC coupling, you remove the large DC
offset for the input amplifier and amplify only the AC component. This
configuration effectively uses the dynamic range of the ADC.

The input impedance for the programmable gain instrumentation amplifier
(PGIA) channels is 1 MΩ for ranges ≤ ±10 V and 10 kΩ for
ranges > ±10 V. This configuration provides an AC-coupled corner
frequency of 2.34 Hz for ranges ≤ ±10 V and 234 Hz for ranges > ±10 V.

NI 6115/6120 User Manual 3-4 ni.com

Analog Output

Note The AO channels do not have analog or digital filtering hardware and do produce

images in the frequency domain related to the update rate.

Analog Trigger

Chapter 3 Hardware Overview

The NI 6115/6120 supplies two channels of AO voltage at the I/O
connector. The range is fixed at bipolar ±10 V.

The AO channels on the NI 6115 contain 12-bit DACs that are capable of
4 MS/s for one channel or 2.5 MS/s for each of two channels. The NI 6120
DACs are 16-bit, and they have the same AO capabilities as the NI 6115.
Refer to Appendix A, Specifications, for more detailed information about
the AO capabilities of the NI 6115/6120.

The NI 6115/6120 includes high-density memory modules allowing for
long waveform generations.

In addition to supporting internal software triggering and external digital
triggering to initiate a DAQ sequence, these devices also support analog
hardware triggering. You can configure the analog trigger circuitry to
accept either a direct analog input from the PFI0/TRIG1 pin on the
I/O connector or a post-gain signal from the output of the PGIA on any of
the channels, as shown in Figure 3-3. The trigger-level range for the direct
analog channel is ±10 V with a resolution of 78 mV for the NI 6115 and

4.88 mV for the NI 6120. The input impedance for the direct analog
channel is 10 kΩ. When this direct analog channel is configured for AC
coupling, the corner frequency is 159 Hz.

The range for the post-PGIA trigger from a selected channel is the
full-scale range of the selected channel with a resolution of that range
divided by 256 for the NI 6115 and 4,096 for the NI 6120.

Two trigger reference signals, lowValue and highValue, can then be
independently set to achieve advanced triggering modes. Refer to
Figures 3-3 through 3-8 for illustrations of these modes.

Note The PFI0/TRIG1 pin is an analog input when configured as an analog trigger.

Therefore, it is susceptible to crosstalk from adjacent pins, which can result in false
triggering when the pin is left unconnected. To avoid false triggering, make sure the
PFI0/TRIG1 pin is connected to a low-impedance signal source (less than 1 kΩ source
impedance) if you plan to enable this input using software.

© National Instruments Corporation 3-5 NI 6115/6120 User Manual

Chapter 3 Hardware Overview

Analog

Input

CH0

Analog

Input

CH1

Analog

Input

CH2

Analog

Input

CH3

+

PGIA

–

+

PGIA

–

+

PGIA

–

+

PGIA

–

PFI0/TRIG1

ADC

ADC

ADC

ADC

AC Couple

Digital Data

Mux

10 k

highValue

Analog
Trigger

Circuit

lowValue

Trigger

DAC

DAQ-STC

Trigger

DAC

Figure 3-3. Analog Trigger Block Diagram for the NI 6115/6120

In below-low-level analog triggering mode, the trigger is generated when
the signal value is less than lowValue, as shown in Figure 3-4. HighValue
is unused.

lowValue

Trigger

Figure 3-4. Below-Low-Level Analog Triggering Mode

In above-high-level analog triggering mode, the trigger is generated when
the signal value is greater than highValue, as shown in Figure 3-5.
LowValue is unused.

NI 6115/6120 User Manual 3-6 ni.com