National Instruments 7340 PCI User Manual

Motion Control

National Instruments 7340 User Manual

NI 7340 User Manual

November 2003 Edition

Part Number 370838A-01

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For further support information, refer to the Technical Support and Professional Services appendix. To comment
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© 2003 National Instruments Corporation. All rights reserved.

Important Information

Warranty

The National Instruments 7340 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 WAR RANTY OF

E

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 CUSTOMER. NATIONAL INSTRUMENTS WILL NOT BE LIABLE FOR
DAMAGES RESULTING FROM LOSS OF DATA, PROFITS, USE OF PRODUCTS, OR INCIDENTAL OR CONSEQUENTIAL DAMAGES, EVEN IF ADVISED OF THE POSS IBILITY
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™, IMAQ™, LabVIEW™, Measurement Studio™, National Instruments™, NI™, ni.com™, NI-Motion™, and RTSI™ are trademarks of
National Instruments Corporation.

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/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
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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). All National Instruments (NI) products are FCC Class A products.

Depending on where it is operated, this Class A 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.

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

Consult the FCC Web site at www.fcc.gov for more information.

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 marking 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 NI could void the user's authority to operate the equipment under the FCC
Rules.

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 is required to correct the interference
at their 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.

Compliance to EU Directives

Users in the European Union (EU) should refer to the Declaration of Conformity (DoC) for information pertaining to the CE
marking. Refer to the Declaration of Conformity (DoC) for this product for any additional regulatory compliance information.
To obtain the DoC for this product, visit ni.com/hardref.nsf, search by model number or product line, and click the appropriate
link in the Certification column.

* The CE marking Declaration of Conformity contains important supplementary information and instructions for the user or

installer.

Contents

About This Manual

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

Related Documentation..................................................................................................viii

Chapter 1
Introduction

About the 7340 Controller .............................................................................................1-1

Features............................................................................................................1-1

Hardware .........................................................................................................1-1

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

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

Software Programming Choices ....................................................................................1-3

National Instruments Application Software ..................................................................1-3

Optional Equipment.......................................................................................................1-3

Motion I/O Connections ................................................................................................1-4

Chapter 2
Configuration and Installation

Software Installation ......................................................................................................2-1

Controller Configuration................................................................................................2-1

Safety Information .........................................................................................................2-1

Hardware Installation.....................................................................................................2-4

Chapter 3
Hardware Overview

User Connectors.............................................................................................................3-3

Chapter 4
Functional Overview

Dual Processor Architecture ..........................................................................................4-1

Embedded Real-Time Operating System (RTOS) ..........................................4-2

Trajectory Generators......................................................................................4-2

Analog Feedback.............................................................................................4-2

Flash Memory..................................................................................................4-3

Axes and Motion Resources ..........................................................................................4-3

Axes.................................................................................................................4-3

Motion Resources............................................................................................4-4

© National Instruments Corporation v NI 7340 User Manual

Contents

Onboard Programs and Buffers..................................................................................... 4-5

Host Communications ................................................................................................... 4-5

Chapter 5
Signal Connections

Motion I/O Connector ................................................................................................... 5-1

Motion Axis Signals........................................................................................ 5-4

Limit and Home Inputs ................................................................................... 5-5

Encoder Signals............................................................................................... 5-7

Trigger Inputs, Shutdown Input, and Breakpoint Outputs .............................. 5-10

Analog Inputs.................................................................................................. 5-12

Other Motion I/O Connection ......................................................................... 5-14

Digital I/O Connector .................................................................................................... 5-15

PWM Features................................................................................................. 5-16

RTSI Connector............................................................................................................. 5-16

RTSI Signal Considerations............................................................................ 5-17

Wiring Concerns............................................................................... 5-6

Limit and Home Input Circuit .......................................................... 5-6

Encoder <1..4> Phase A/Phase B ..................................................... 5-7

Encoder <1..4> Index ....................................................................... 5-8

Wiring Concerns............................................................................... 5-9

Encoder Input Circuit ....................................................................... 5-9

Wiring Concerns............................................................................... 5-11

Trigger Input, Shutdown Input, and Breakpoint Output Circuits ..... 5-11

Wiring Concerns............................................................................... 5-13

Appendix A
Specifications

Appendix B
Cable Connector Descriptions

Appendix C
Technical Support and Professional Services

Glossary

Index

NI 7340 User Manual vi ni.com

About This Manual

This manual describes the electrical and mechanical aspects of the
PXI/PCI-7340 and contains information about how to operate and program
the device.

The 7340 is designed for PXI, Compact PCI, and PCI bus computers

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.

bold Bold text denotes items that you must select or click 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.

© National Instruments Corporation vii NI 7340 User Manual

About This Manual

Related Documentation

The following documents contain information you might find helpful as
you read this manual:

• NI-Motion User Manual

• NI-Motion C Reference Help

• NI-Motion VI Reference Help

NI 7340 User Manual viii ni.com

Introduction

This chapter includes information about the features of the PXI/PCI-7340
controller and information about operating the device.

About the 7340 Controller

The 7340 controller features advanced motion control with easy-to-use
software tools and add-on motion VI libraries for use with LabVIEW.

Features

The 7340 is a combination servo and stepper motor controller for PXI,
Compact PCI, and PCI bus computers. The 7340 provides fully
programmable motion control for up to four independent or coordinated
axes of motion, with dedicated motion I/O for limit and home switches and
additional I/O for general-purpose functions.

You can use the 7340 to perform arbitrary and complex motion trajectories
using stepper motors or servo devices.

1

Servo axes can control servo motors, servo hydraulics, servo valves, and
other servo devices. Servo axes always operate in closed-loop mode. These
axes use quadrature encoders or analog inputs for position and velocity
feedback and provide analog command outputs with an industry-standard
range of ±10 V.

Stepper axes can operate in open or closed-loop mode. In closed-loop
mode, they use quadrature encoders or analog inputs for position and
velocity feedback (closed-loop only), and provide step/direction or
clockwise (CW) /counter-clockwise (CCW) digital command outputs.
All stepper axes support full, half, and microstepping applications.

Hardware

The 7340 uses an advanced dual-processor architecture that uses a 32-bit
CPU, combined with a digital signal processor (DSP) and custom field
programmable gate arrays (FPGAs), making the controller a
high-performance device. The first-in-first-out (FIFO) bus interface and

© National Instruments Corporation 1-1 NI 7340 User Manual

Chapter 1 Introduction

RTSI

powerful function set provide high-speed communications while
off-loading complex motion functions from the host PC for optimum
command throughput and system performance.

With the 7340, you can use full onboard programming to execute up to
10 simultaneous motion programs.

The 7340 features motion profiles that are controlled with enhanced

PID/PIVff servo updates. Each axis has motion I/O for end-of-travel limit

and home switch inputs, breakpoint output, trigger input, and encoder
feedback. Refer to Appendix A, Specifications, for information about the
feedback rates. The 7340 also has non-dedicated user I/O including 32 bits
of digital I/O and four analog inputs for ±10 V signals, joystick inputs, or
monitoring of analog sensors. Additionally, the 7340 analog inputs can
provide feedback for loop closure.

The 7340 supports the National Instruments Real-Time System Integration
(RTSI) bus. The RTSI bus provides high-speed connectivity between
National Instruments products, including image acquisition (IMAQ) and
data acquisition (DAQ) products. Using the RTSI bus, you can easily
synchronize several functions to a common trigger or timing event across
multiple motion, IMAQ, or DAQ devices.

What You Need to Get Started

To set up and use the 7340 controller, you must have the following items:

❑ NI PXI-7340 or PCI-7340 motion controller

❑ This manual

❑ NI-Motion 6.1 or later driver software and documentation

❑ One of the following software packages and documentation:

– LabVIEW 6.0 or later

™

– LabWindows

– Measurement Studio

–C/C++

– Microsoft Visual Basic

❑ A computer with an available PXI or PCI slot

NI 7340 User Manual 1-2 ni.com

/CVI

™

Software Programming Choices

NI-Motion is a simple but powerful high-level application programming
interface (API) that makes programming the 7340 easy. All setup and
motion control functions are easily executed by calling into a
dynamically-linked library (DLL). You can call these libraries from C,
Microsoft Visual Basic, and other high-level languages. Full function sets
are available for LabVIEW, LabWindows/CVI, and other
industry-standard software programs.

National Instruments Application Software

LabVIEW is based on the graphical programming language, G, and
features interactive graphics and a state-of-the-art user interface. In
LabVIEW, you can create 32-bit compiled programs and stand-alone
executables for custom automation, data acquisition, test, measurement,
and control solutions. National Instruments offers the NI-Motion driver
software support for LabVIEW, which includes a series of virtual
instruments (VIs) for using LabVIEW with National Instruments motion
control hardware. The NI-Motion VI library implements the NI-Motion
API and a powerful set of demo functions; example programs; and fully
operational, high-level application routines.

Chapter 1 Introduction

ANSI C-based LabWindows/CVI also features interactive graphics and a
state-of-the-art user interface. Using LabWindows/CVI, you can generate
C code for custom data acquisition, test, and measurement and automation
solutions. NI-Motion includes a series of sample programs for using
LabWindows/CVI with National Instruments motion control hardware.

Optional Equipment

National Instruments offers a variety of products for use with the
7340 controller, including the following accessories:

• Cables and cable assemblies for motion and digital I/O

• Universal Motion Interface (UMI) wiring connectivity blocks with
integrated motion signal conditioning and motion inhibit functionality

• Stepper and servo motor compatible drive amplifier units with
integrated power supply and wiring connectivity

• Connector blocks and shielded and unshielded 68-pin screw terminal
wiring aids

© National Instruments Corporation 1-3 NI 7340 User Manual

Chapter 1 Introduction

For more specific information about these products, refer to the
National Instruments catalog, the National Instruments Web site at

ni.com, or call your National Instruments sales representative.

Motion I/O Connections

The external motion and digital I/O connectors on the 7340 are
high-density, 68-pin female VHDCI connectors.

For custom cables, use the AMP mating connector (part number
787801-1).

NI 7340 User Manual 1-4 ni.com

Configuration and Installation

This chapter describes how to configure and install the PXI/PCI-7340.

Software Installation

Before installing the 7340, install the NI-Motion driver software. Refer to
the Getting Started with NI Motion Control manual, which is included with
the controller, for specific installation instructions.

Note If you do not install the NI-Motion driver software before attempting to use the

7340, the system does not recognize the 7340 and you are unable to configure or use the
device.

Controller Configuration

Because motion I/O-related configuration of the 7340 is performed entirely
with software, it is not necessary to set jumpers for motion I/O
configuration.

2

The PXI-7340 and PCI-7340 controllers are fully compatible with the
industry standard PXI Specification, Revision 2.0 and the PCI Local Bus
Specification, Revision 2.2, respectively. This compatibility allows the PXI
or PCI system to automatically perform all bus-related configuration and
requires no user interaction. It is not necessary to configure jumpers for
bus-related configuration, including setting the device base memory and
interrupt channel.

Safety Information

Caution The following paragraphs contain important safety information you must follow

when installing and operating the 7340 and all devices connecting to the 7340.

Do not operate the device in a manner not specified in the documentation.
Misuse of the device may result in a hazard and may compromise the safety
protection built into the device. If the device is damaged, turn it off and do

© National Instruments Corporation 2-1 NI 7340 User Manual

Chapter 2 Configuration and Installation

not use it until service-trained personnel can check its safety. If necessary,
return the device to National Instruments for repair.

Keep away from live circuits. Do not remove equipment covers or shields
unless you are trained to do so. If signal wires are connected to the device,
hazardous voltages can exist even when the equipment is turned off. To
avoid a shock hazard, do not perform procedures involving cover or shield
removal unless you are qualified to do so. Disconnect all field power prior
to removing covers or shields.

If the device is rated for use with hazardous voltages (>30 V
or 60 V

), it may require a safety earth-ground connection wire. Refer to

dc

, 42.4 Vpk,

rms

the device specifications for maximum voltage ratings.

Because of the danger of introducing additional hazards, do not install
unauthorized parts or modify the device. Use the device only with the
chassis, modules, accessories, and cables specified in the installation
instructions. All covers and filler panels must be installed while operating
the device.

Do not operate the device in an explosive atmosphere or where flammable
gases or fumes may be present. Operate the device only at or below the
pollution degree stated in the specifications. Pollution consists of any
foreign matter—solid, liquid, or gas—that may reduce dielectric strength
or surface resistivity. Pollution degrees are listed below.

• Pollution Degree 1—No pollution or only dry, nonconductive
pollution occurs. The pollution has no effect.

• Pollution Degree 2—Normally only nonconductive pollution occurs.
Occasionally, nonconductive pollution becomes conductive because of
condensation.

• Pollution Degree 3—Conductive pollution or dry, nonconductive
pollution occurs. Nonconductive pollution becomes conductive
because of condensation.

Note The 7340 is intended for indoor use only.

Clean the device and accessories by brushing off light dust with a soft,
nonmetallic brush. Remove other contaminants with a stiff, nonmetallic
brush. The unit must be completely dry and free from contaminants before
returning it to service.

Yo u must insulate signal connections for the maximum voltage for which
the device is rated. Do not exceed the maximum ratings for the device.

NI 7340 User Manual 2-2 ni.com

Chapter 2 Configuration and Installation

Remove power from signal lines before connection to or disconnection
from the device.

Caution National Instruments measurement products may be classified as either

Installation Category I or II. Operate products at or below the Installation Category level
specified in the hardware specifications.

1

Installation Category
voltages

2

and transient stresses (overvoltage) from the circuit to which they

: Measurement circuits are subjected to working

are connected during measurement or test. Installation Category establishes
standardized impulse withstand voltage levels that commonly occur in
electrical distribution systems. The following is a description of Installation
(Measurement

3

) Categories:

• Installation Category I is for measurements performed on circuits not
directly connected to the electrical distribution system referred to as
MAINS

4

voltage. This category is for measurements of voltages from
specially protected secondary circuits. Such voltage measurements
include signal levels, special equipment, limited-energy parts of
equipment, circuits powered by regulated low-voltage sources, and
electronics.

• Installation Category II is for measurements performed on circuits
directly connected to the electrical distribution system. This category
refers to local-level electrical distribution, such as that provided by a
standard wall outlet (e.g., 115 V for U.S. or 230 V for Europe).
Examples of Installation Category II are measurements performed on
household appliances, portable tools, and similar products.

• Installation Category III is for measurements performed in the building
installation at the distribution level. This category refers to
measurements on hard-wired equipment such as equipment in fixed
installations, distribution boards, and circuit breakers. Other examples
are wiring, including cables, bus-bars, junction boxes, switches,
socket-outlets in the fixed installation, and stationary motors with
permanent connections to fixed installations.

• Installation Category IV is for measurements performed at the primary
electrical supply installation (<1,000 V). Examples include electricity

1

Installation Categories as defined in electrical safety standard IEC 61010-1.

2

Working voltage is the highest rms value of an AC or DC voltage that can occur across any particular insulation.

3

Installation Category is also referred to as Measurement Category.

4

MAINS is defined as the (hazardous live) electrical supply system to which equipment is designed to be connected for the
purpose of powering the equipment. Suitably rated measuring circuits may be connected to the MAINS for measuring
purposes.

© National Instruments Corporation 2-3 NI 7340 User Manual

Chapter 2 Configuration and Installation

meters and measurements on primary overcurrent protection devices
and on ripple control units.

Hardware Installation

Install the 7340 in any open compatible expansion slot in the PXI or PCI
system. Appendix A, Specifications, lists the typical power required for
each controller.

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

Caution The 7340 is a sensitive electronic device shipped in an antistatic bag. Open only

at an approved workstation and observe precautions for handling electrostatic-sensitive
devices.

Note When adding or removing a controller from a Windows 2000/NT/XP system, you

must be logged on with administrator-level access. After you have restarted the system, you
may need to refresh Measurement & Automation Explorer (MAX) to view the new
controller.

♦ PXI-7340

1. Power off and unplug the chassis.

Caution To protect yourself and the computer from electrical hazards, the computer must

remain unplugged until the installation is complete.

2. Choose an unused +3.3 V or +5 V peripheral slot and remove the filler
panel.

3. Touch a metal part on the chassis to discharge any static electricity that
might be on your clothes or body. Static electricity can damage the
controller.

4. Insert the PXI controller into the chosen slot. Use the injector/ejector
handle to fully inject the device into place.

5. Screw the front panel of the PXI controller to the front panel mounting
rails of the chassis.

6. Visually verify the installation.

7. Plug in and power on the chassis.

NI 7340 User Manual 2-4 ni.com

Chapter 2 Configuration and Installation

♦ PCI-7340

1. Power off and unplug the computer.

Caution To protect yourself and the computer from electrical hazards, the computer must

remain unplugged until the installation is complete.

2. Remove the cover to expose access to the PCI expansion slots.

3. Choose an unused 5 V PCI slot, and remove the corresponding
expansion slot cover on the back panel of the computer.

4. Touch a metal part on the computer case to discharge any static
electricity that might be on your clothes or body before handling the
controller. Static electricity can damage the controller.

5. Gently rock the controller into the slot. The connection may be tight,
but do not force the controller into place.

6. If required, screw the mounting bracket of the controller to the back
panel rail of the computer.

7. Replace the cover.

8. Plug in and power on the computer.

© National Instruments Corporation 2-5 NI 7340 User Manual

Hardware Overview

This chapter presents an overview of the PXI/PCI-7340 hardware
functionality.

Figures 3-1 and 3-3 show the PXI-7340 and PCI-7340 parts locator
diagrams, respectively.

5

3

1

4

23

1 Serial Number Label
2DSP
3CPU

Note

The PXI-7340 assembly number is located on the back of the PXI module.

© National Instruments Corporation 3-1 NI 7340 User Manual

4 68-Pin Digital I/O Connector
5 68-Pin Motion I/O Connector

Figure 3-1. PXI-7340 Parts Locator Diagram

Chapter 3 Hardware Overview

1 2 3

1 Identification Number Used in Australia
2 Symbol Indicating FFC Compliance

9 10

8

7

3 Symbol to Alert User to Read the Manual

Figure 3-2. Symbols on the Back of the PXI-7340

ASSY186307D-01

NI PCI-7340

6

1

2

3

4

5

1 RTSI Connector
2 Serial Number Label
3 Symbol to Alert User to Read the Manual
4 Symbol Indicating FFC Compliance
5 Identification Number Used in Australia

6 Assembly Number Label
7 68-Pin Digital I/O Connector
8 68-Pin Motion I/O Connector
9CPU
10 DSP

Figure 3-3. PCI-7340 Parts Locator Diagram

NI 7340 User Manual 3-2 ni.com

User Connectors

The 68-pin motion I/O connector provides all the signals for four axes of
closed-loop motion control, including encoder feedback, limit and home
inputs, breakpoint outputs, trigger inputs, digital-to-analog (DAC), and
analog-to-digital (ADC) converter signals. Refer to Chapter 5, Signal

Connections, for details about the signals in the motion I/O connector.

The 68-pin digital I/O connector provides 32 bits of user-configurable
digital I/O. Refer to Chapter 5, Signal Connections, for details about the
signals in the digital I/O connector.

The PCI-7340 RTSI connector provides up to eight triggers to facilitate
synchronization between multiple National Instruments products. The
PXI-7340 RTSI-enabled connection provides up to eight triggers and one
PXI star trigger to facilitate synchronization between multiple National
Instruments PXI-enabled products. Typical applications of the RTSI bus
include triggering an image acquisition or DAQ measurement based on
motion events, or capturing current motion positions based on events
external to the motion controller. You also can use the RTSI bus for general
hardware-based communication between RTSI devices.

Chapter 3 Hardware Overview

The RTSI bus also can be used for general-purpose I/O. Refer to Chapter 5,

Signal Connections, for details about RTSI connector signals.

© National Instruments Corporation 3-3 NI 7340 User Manual

Functional Overview

This chapter provides an overview of motion control algorithms and the
PXI/PCI-7340 controller.

Dual Processor Architecture

With the 7340, you can perform up to four axes of simultaneous,
coordinated motion control in a preemptive, multitasking, real-time
environment.

An advanced dual-processor architecture that uses a 32-bit CPU combined
with a digital signal processor (DSP) and custom FPGAs give the 7340
high-performance capabilities. The FIFO bus interface and powerful
function set provide high-speed communications while off-loading
complex motion functions from the host PC for optimized system
performance.

The 7340 uses the DSP for all closed-loop control, including position
tracking, PID control closed-loop computation, and motion trajectory
generation. The DSP chip is supported by custom FPGAs that perform the
high-speed encoder interfacing, position capture and breakpoint functions,
motion I/O processing, and stepper pulse generation for hard real-time
functionality.

4

The embedded, multitasking real-time CPU handles host communications,
command processing, multi-axis interpolation, onboard program
execution, error handling, general-purpose digital I/O, and overall motion
system integration functions.

© National Instruments Corporation 4-1 NI 7340 User Manual

Chapter 4 Functional Overview

Embedded Real-Time Operating System (RTOS)

The embedded firmware is based on an embedded RTOS kernel and
provides optimum system performance in varying motion applications.
Motion tasks are prioritized. Task execution order depends on the priority
of each task, the state of the entire motion system, I/O or other system
events, and the real-time clock.

The DSP chip is a separate processor that operates independently from
the CPU but is closely synchronized. The 7340 is a true multiprocessing
and multitasking embedded controller.

The advanced architecture of the 7340 enables advanced motion features,
such as enhanced PID functions. Refer to the NI-Motion User Manual for
more information about the features available on the 7340.

Trajectory Generators

The 7340 trajectory generators calculate the instantaneous position
command that controls acceleration and velocity while it moves the axis to
its target position. Depending on how you configure the axis, this command
is then sent to the PID servo loop or stepper pulse generator.

To implement infinite trajectory control, the 7340 has eight trajectory
generators implemented in the DSP chip (two per axis). Each generator
calculates an instantaneous position for each PID update period. While
simple point-to-point moves require only one trajectory generator,
two simultaneous generators are required for blended moves and infinite
trajectory control processing.

Analog Feedback

The 7340 has an 8-channel multiplexed, 12-bit ADC. The converted analog
values are broadcast to both the DSP and CPU through a dedicated internal
high-speed serial bus. The multiplexer provides the high sampling rates
required for feedback loop closure, joystick inputs, or monitoring analog
sensors. Refer to Appendix A, Specifications, for the multiplexer scan rate.
Four of these channels are intended for calibration, leaving the other four
available for analog feedback.

NI 7340 User Manual 4-2 ni.com

Flash Memory

Nonvolatile memory on the 7340 is implemented with flash ROM, which
means that the controllers can electrically erase and reprogram their own
ROM. Because all the 7340 embedded firmware, including the RTOS and
DSP code, is stored in flash memory, you can upgrade the onboard
firmware contents in the field for support and new feature enhancement.

Flash memory also allows objects such as programs and data arrays to be
stored in non-volatile memory. It is possible to save the entire parameter
state of the controller to the flash memory. On the next power cycle, the
controller automatically loads and returns the configuration to these new
saved default values.

The FPGA configuration programs also are stored in the flash ROM.
At power-up, the FPGAs are booted with these programs, which means
that updates to the FPGA programs can be performed in the field.

A flash memory download utility is included with the NI-Motion software
that ships with the controller.

Axes and Motion Resources

Chapter 4 Functional Overview

The 7340 can control up to four axes of motion. The axes can be completely
independent, simultaneously coordinated, or mapped in multidimensional
groups called coordinate spaces. You also can synchronize coordinate
spaces for multi-vector space coordinated motion control.

Axes

At a minimum, an axis consists of a trajectory generator, a PID (for servo
axes) or stepper control block, and at least one output resource—either
a DAC output (for servo axes) or a stepper pulse generator output. Servo
axes must have either an encoder or ADC channel feedback resource.
Closed-loop stepper axes also require a feedback resource, while open-loop
stepper axes do not. Figures 4-1 and 4-2 show these axis configurations.

With the 7340, you can map one or two feedback resources and one or two
output resources to the axis. An axis with its primary output resource
mapped to a stepper output is by definition a stepper axis. An axis with its
primary output resource mapped to a DAC is by definition a servo axis.

© National Instruments Corporation 4-3 NI 7340 User Manual

Chapter 4 Functional Overview

Optional

øA

øB

Index

101100111

32-Bit

Encoder

Interface

0101011101101

PID

Servo

Loop

101100111

11101101100

16-Bit

D/A

Converter

±10 V

Figure 4-1. Servo Axis Resources

Trajectory
Generator

101100111

øA

Index

32-Bit
Encoder
Interface

01011010

Stepper

Control

101100111

010010110

Loop

Stepper

Pulse

Generator

Figure 4-2. Stepper Axis Resources

The 7340 supports axes with secondary output resources, such as DACs for
servo axes or stepper outputs. Defining two output resources is useful when
controlling axes with multiple motors, such as gantry systems in which
two DAC outputs can be configured with different torque limits and/or
offsets.

The 7340 controller also supports secondary feedback resources, called
encoders, for axes defined as servo. Two feedback resources are used when
implementing dual-loop control, such as in backlash compensation,
which reduces the number of encoders available for other axes.

Note Refer to the NI-Motion User Manual for information about configuring axes.

Motion Resources

Encoder, DAC, ADC, and motion I/O resources that are not used by an axis
are available for non-axis or nonmotion-specific applications. You can
directly control an unmapped DAC as a general-purpose analog output
(±10 V). Similarly, you can use any ADC channel to measure
potentiometers or other analog sensors.

NI 7340 User Manual 4-4 ni.com

If an encoder resource is not needed for axis control, you can use it for any
number of other functions, including position or velocity monitoring, as a
digital potentiometer encoder input, or as a master encoder input for
master/slave (electronic gearing) applications.

Each axis also has an associated forward and reverse limit input, a home
input, a high-speed capture trigger input, a breakpoint output, and an inhibit
output. These signals can be used for general-purpose digital I/O when not
being used for their motion-specific purpose.

Onboard Programs and Buffers

The 7340 controller has full onboard programmability capable of executing
up to 10 simultaneous motion programs.

You can execute the NI-Motion function set from onboard programs.
In addition, the onboard programs support basic math and data operation
functions for up to 120 general-purpose variables.

You can store and run onboard programs and buffers from RAM or save
them to flash ROM. The 7340 controller has 64 KB of RAM and 128 KB
of ROM that is divided into two 64 KB sectors for program and buffer
storage. You can store and run programs and buffers from either RAM or
ROM, but you cannot split programs between the two, and you cannot split
programs or buffers between the two 64 KB ROM sectors.

Chapter 4 Functional Overview

Note Refer to the NI-Motion User Manual for detailed information about all of these

onboard programming and buffer features.

Host Communications

The host computer communicates with the controller through a number of
memory port addresses on the host bus. The host bus can be either PXI or
PCI.

The primary bidirectional data transfer port supports FIFO data passing
in both send and readback directions. The 7340 controller has both a
command buffer for incoming commands and a return data buffer (RDB)
for returning data.

© National Instruments Corporation 4-5 NI 7340 User Manual

Chapter 4 Functional Overview

The communications status register (CSR) provides bits for
communications handshaking as well as real-time error reporting and
general status feedback to the host PC. The move complete status (MCS)
register provides instantaneous motion status of all axes.

NI 7340 User Manual 4-6 ni.com

Signal Connections

This chapter describes how to make input and output signal connections
directly to the PXI/PCI-7340 as well as general information about the
associated I/O circuitry.

The 7340 has three connectors that handle all signals to and from the
external motion system.

• 68-pin motion I/O connector

• 68-pin digital I/O connector

• RTSI connector

You can connect to your motion system with cables and accessories,
varying from simple screw terminal blocks to enhanced Universal Motion
Interface (UMI) units and drives.

Note The 7340 does not provide isolation between circuits.

Caution Turn off power to all devices when connecting or disconnecting the

7340 controller motion I/O and auxiliary digital I/O cables. Failure to do so may damage
the controller.

5

Motion I/O Connector

The motion I/O connector contains all of the signals required to control up
to four axes of servo and stepper motion, including the following features:

• Motor command analog and stepper outputs

• Encoder feedback inputs

• Forward, home, and reverse limit inputs

• Breakpoint outputs

• Trigger inputs

• Inhibit outputs

The motion I/O connector also contains four channels of 12-bit A/D inputs
for analog feedback or general-purpose analog input.

© National Instruments Corporation 5-1 NI 7340 User Manual

Chapter 5 Signal Connections

Figure 5-1 shows the pin assignments for the 68-pin motion I/O connector
on the 7340. Table 5-1 includes descriptions for each of the signals. A line
above a signal name indicates that the signal is active-low.

Axis 1 Dir (CCW)

Digital Ground

Digital Ground

Axis 1 Home Switch

Trigger 1

Axis 1 Inhibit

Axis 2 Dir (CCW)

Digital Ground

Digital Ground

Axis 2 Home Switch

Trigger 2

Axis 2 Inhibit

Axis 3 Dir (CCW)

Digital Ground

Digital Ground

Axis 3 Home Switch

Trigger 3

Axis 3 Inhibit

Axis 4 Dir (CCW)

Digital Ground

Digital Ground

Axis 4 Home Switch

Trigger 4

Axis 4 Inhibit

Digital Ground

Breakpoint 1
Breakpoint 3

Digital Ground

Analog Output

Analog Output

Analog Output Ground

Analog Input 1

Analog Input 3

Analog Reference (Output)

135

236

337

438

539

640

741

842

943

10 44

11 45

12 46

13 47

14 48

15 49

16 50

17 51

18 52

19 53

20 54

21 55

22 56

23 57

24 58

25 59

26 60

27 61

28 62

29 63

30 64

31 65

32 66

33 67

34 68

Axis 1 Step (CW)
Axis 1 Encoder Phase A

Axis 1 Encoder Phase B

Axis 1 Encoder Index

Axis 1 Forward Limit Switch

Axis 1 Reverse Limit Switch

Axis 2 Step (CW)

Axis 2 Encoder Phase A

Axis 2 Encoder Phase B
Axis 2 Encoder Index
Axis 2 Forward Limit Switch

Axis 2 Reverse Limit Switch

Axis 3 Step (CW)

Axis 3 Encoder Phase A

Axis 3 Encoder Phase B

Axis 3 Encoder Index

Axis 3 Forward Limit Switch

Axis 3 Reverse Limit Switch

Axis 4 Step (CW)
Axis 4 Encoder Phase A
Axis 4 Encoder Phase B

Axis 4 Encoder Index

Axis 4 Forward Limit Switch

Axis 4 Reverse Limit Switch

Host +5 V

Breakpoint 2

Breakpoint 4

Shutdown

Analog Output
Analog Output

Reserved

Analog Input 2

Analog Input 4

Analog Input Ground

Figure 5-1. 68-Pin Motion I/O Connector Pin Assignment

NI 7340 User Manual 5-2 ni.com

Chapter 5 Signal Connections

Table 5-1 describes the signals on the motion I/O connector.

Table 5-1. Motion I/O Signal Connections

Signal Name Reference Direction Description

Axis <1..4> Dir (CCW) Digital Ground Output Motor direction or

counter-clockwise control

Axis <1..4> Step (CW) Digital Ground Output Motor step or clockwise control

Axis <1..4> Encoder Phase A Digital Ground Input Closed-loop only—phase A encoder

input

Axis <1..4> Encoder Phase B Digital Ground Input Closed-loop only—phase B encoder

input

Axis<1..4> Encoder Index Digital Ground Input Closed-loop only—index encoder

input

Axis <1..4> Home Switch Digital Ground Input Home switch

Axis <1..4> Forward Limit Switch Digital Ground Input Forward/clockwise limit switch

Axis <1..4> Reverse Limit Switch Digital Ground Input Reverse/counter-clockwise limit

switch

Axis <1..4> Inhibit Digital Ground Output Drive inhibit

Trigger <1..4> Digital Ground Input High-speed position capture trigger

Breakpoint <1..4> Digital Ground Output Breakpoint output <1..4>

Host +5 V Digital Ground Output +5 V—host computer +5 V supply

Analog Input Ground — — Reference for analog inputs

Analog Input <1..4> Analog Input Ground Input 12-bit analog input

Analog Output <1..4> Analog Output Ground Output 16-bit analog output

Analog Output Ground — — Reference for analog outputs

Shutdown Digital Ground Input Controlled device shutdown

Analog Reference (output) Analog Input Ground Output +7.5 V—analog reference level

Digital Ground — — Reference for digital I/O

input <1..4>

© National Instruments Corporation 5-3 NI 7340 User Manual

Chapter 5 Signal Connections

Motion Axis Signals

The following signals control the servo amplifier or stepper driver.

• Analog Output <1..4>—These 16-bit DAC outputs are typically
the servo command outputs for each axis. They can drive the
industry-standard ±10 V output, and can be software limited to
any positive or negative voltage range. They also feature
a software-programmable voltage offset.

Although typically used as the command output of an axis control
loop, unused DACs also can function as independent analog outputs
for general-purpose control.

• Analog Output Ground—To help keep digital noise separate from the
analog DAC outputs, there is a separate return connection. Use this
analog ground connection and not Digital Ground (digital I/O
reference) as the reference for the DAC outputs when connecting to
servo amplifiers.

• Axis <1..4> Step (CW) and Dir (CCW)—These open-collector signals
are the stepper command outputs for each axis. The 7340 supports both
major industry standards for stepper command signals: step and
direction, or independent CW and CCW pulse outputs.

The output configuration and signal polarity is software programmable
for compatibility with various third-party drives, as follows:

– When step and direction mode is configured, each commanded

step (or microstep) produces a pulse on the step output. The
direction output signal level indicates the command direction of
motion, either forward or reverse.

– CW and CCW mode produces pulses (steps) on the CW output for

forward-commanded motion and pulses on the CCW output for
reverse-commanded motion.

In either case, you can set the active polarity of both outputs to
active-low (inverting) or active-high (non-inverting). For example,
with step and direction, you can make a logic high correspond to either
forward or reverse direction.

The Step (CW) and Dir (CCW) outputs are driven by high-speed
open-collector TTL buffers that feature 64 mA sink current capability
and built-in 3.3 kΩ pull-up resistors to +5 V.

Caution Do not connect these outputs to anything other than a +5 V circuit. The output

buffers will fail if subjected to voltages in excess of +5.5 V.

NI 7340 User Manual 5-4 ni.com

• Axis <1..4> Inhibit—Use the inhibit output signals to control the

Limit and Home Inputs

The following signals control limit and home inputs.

• Axis <1..4> Forward Limit Input

• Axis <1..4> Home Input

• Axis <1..4> Reverse Limit Input

Chapter 5 Signal Connections

enable/inhibit function of a servo amplifier or stepper driver. When
properly connected and configured, the inhibit function causes the
connected motor to be de-energized and its shaft turns freely. These
open-collector inhibit signals feature 64 mA current sink capability
with built-in 3.3 kΩ pull-up resistors to +5 V, and can directly drive
most driver/amplifier inhibit input circuits.

While the industry standard for inhibits is active-low (inverting), these
outputs have programmable polarity and can be set to active-high
(non-inverting) for increased flexibility and unique drive
compatibility.

Inhibit output signals can be activated automatically upon a shutdown
condition, a Kill Motion command, or any motion error that causes a
kill motion condition, such as following error trip. You also can
directly control the inhibit output signals to enable or disable a driver
or amplifier.

These inputs are typically connected to limit switches located at physical
ends of travel and/or at a specific home position. Limit and home inputs can
be software enabled or disabled at any time. When enabled, an active
transition on a limit or home input causes a full torque halt stop of the
associated motor axis. In addition, an active forward or reverse limit input
impedes future commanded motion in that direction for as long as the
signal is active.

Note By default, limit and home inputs are digitally filtered and must remain active for at

least 1 ms to be recognized. You can use MAX to disable digital filtering for limit and home
inputs. Active signals should remain active to prevent motion from proceeding further into
the limit. Pulsed limit signals stop motion, but they do not prevent further motion in that
direction if another move is started.

The input polarity of these signals is software programmable for active-low
(inverting) or active-high (non-inverting).

© National Instruments Corporation 5-5 NI 7340 User Manual

Chapter 5 Signal Connections

Caution National Instruments recommends using limits for personal safety, as well as to

protect the motion system.

Caution Failure to follow these guidelines may result in motion that stops at, but then

travels through, a limit, potentially damaging the motion system. Miswired limits may
prevent motion from occurring at all.

You can use software disabled limit and home inputs as general-purpose
inputs. You can read the status of these inputs at any time and set and
change their polarity as required.

Limit and home inputs are a per axis enhancement on the 7340 and are not
required for basic motion control. These inputs are part of a system solution
for complete motion control.

Wiring Concerns

For the end of travel limits to function correctly, the forward limit must be
located at the forward or positive end of travel, and the reverse limit at the
negative end of travel.

Keep limit and home switch signals and their ground connections wired
separately from the motor driver/amplifier signal and encoder signal
connections.

Caution Wiring these signals near each other can cause faulty motion system operation

due to signal noise and crosstalk.

Limit and Home Input Circuit

By default, all limit and home inputs are digitally filtered and must be
active for at least 1 ms. You can use MAX to disable digital filtering for
limit and home inputs. Figure 5-2 shows a simplified schematic diagram of
the circuit used by the limit and home switch inputs for input signal
buffering and detection.

NI 7340 User Manual 5-6 ni.com

Vcc

Chapter 5 Signal Connections

From the external
connector limit
and home switch pins

Caution

Excessive input voltages can cause erroneous operation and/or component

failure. Verify that the input voltage is within the specification range.

Encoder Signals

3.3 kΩ

74FCT244

1 kΩ

1/8 W

DGND

Figure 5-2. Limit and Home Input Circuit

To the limit and home
switch circuits

The 7340 offers four channels of single-ended quadrature encoder inputs.
All National Instruments power drives and UMI accessories provide
built-in circuitry that converts differential encoder signals to single-ended
encoder signals. Each channel consists of a Phase A, Phase B, and Index
input, as described in the following sections.

Encoder <1..4> Phase A/Phase B

The encoder inputs provide position and velocity feedback for absolute
and relative positioning of axes in any motion system configuration.

If an encoder resource is not needed for axis control, it is available for other
functions including position or velocity monitoring, digital potentiometer
encoder inputs, or as a master encoder input for master/slave (electronic
gearing) applications.

The encoder channels (Encoder <1..4>) are implemented in an FPGA
and are high performance with extended input frequency response and
advanced features, such as high-speed position capture inputs and
breakpoint outputs.

An encoder input channel converts quadrature signals on Phase A and
Phase B into 32-bit up/down counter values. Quadrature signals are
generated by optical, magnetic, laser, or electronic devices that provide
two signals, Phase A and Phase B, that are 90° out of phase. The leading
phase, A or B, determines the direction of motion. The four transition states

© National Instruments Corporation 5-7 NI 7340 User Manual

Chapter 5 Signal Connections

Tip Determine quadrature counts by multiplying the encoder resolution in encoder lines

by four. The encoder resolution is the number of encoder lines between consecutive
encoder marker or Z-bit indexes. If the encoder does not have an index output, the
resolution is referred to as lines per revolution, or lines per unit of measure, such as inch,
centimeter, millimeter, and so on.

of the relative signal phases provide distinct pulse edges that cause count
up or count down pulses in the direction determined by the leading phase.

A typical encoder with a specification of N (N = number) lines per unit
of measure (revolutions or linear distance) produces 4 × N quadrature
counts per unit of measure. The count is the basic increment of position
in NI-Motion systems.

Encoder <1..4> Index

The Index input is primarily used to establish a reference position. This
function uses the number of counts per revolution or the linear distance to
initiate a search move that locates the index position. When a valid Index
signal transition occurs during a Find Reference routine, the position of the
Index signal is captured accurately. Use this captured position to establish
a reference zero position for absolute position control or any other motion
system position reference required.

The default MAX settings guarantee that the Find Index routine completes
successfully if the encoder generates a high index pulse when phases A
and B are low and the encoder is connected through an NI UMI or drive
accessory. Figure 5-3 shows the default encoder phasing diagram at the
inputs to the controller.

Phase A

Phase B

Index

Figure 5-3. Quadrature Encoder Phasing Diagram

You can set the index reference criteria in MAX to change the pattern of
phases A and B for the index search. You also can set the encoder polarity
for phases A, B, and I in MAX.

NI 7340 User Manual 5-8 ni.com

Chapter 5 Signal Connections

Wiring Concerns

The encoder inputs are connected to quadrature decoder/counter circuits.
It is very important to minimize noise at this interface. Excessive noise on
these encoder input signals may result in loss of counts or extra counts and
erroneous closed-loop motion operation. Verify the encoder connections
before powering up the system.

Caution Wire encoder signals and their ground connections separately from all other

connections. Wiring these signals near the motor drive/amplifier or other signals can cause
positioning errors and faulty operation.

Encoders with differential line driver outputs are strongly recommended
for all applications and must be used if the encoder cable length is longer
than 3.05 m (10 ft). Shielded, 24 AWG wire is the minimum recommended
size for the encoder cable. Cables with twisted pairs and an overall shield
are recommended for optimized noise immunity.

All National Instruments power drives and UMI accessories provide
built-in circuitry that converts differential encoder signals to single-ended
encoder signals.

Caution Unshielded cable can cause noise to corrupt the encoder signals, resulting in lost

counts and reduced motion system accuracy.

Encoder Input Circuit

Figure 5-4 shows a simplified schematic diagram of the circuit used for
the Phase A, Phase B, and Index encoder inputs. Both phases A and B are
required for proper encoder counter operation, and the signals must support
the 90° phase difference within system tolerance. The encoder and Index
signals are conditioned by a software-programmable digital filter inside
the FPGA. The Index signal is optional but highly recommended and
required for initialization functionality with the Find Index function.

© National Instruments Corporation 5-9 NI 7340 User Manual

Chapter 5 Signal Connections

Vcc

3.3 kΩ

From the external
connector
encoder input
pins

74FCT244

1 kΩ

1/8 W

DGND

Figure 5-4. Encoder Input Circuit

To the quadrature
decoder circuit

Trigger Inputs, Shutdown Input, and Breakpoint Outputs

The 7340 offers additional high-performance features in the encoder
FPGA. The encoder channels have high-speed position capture trigger
inputs and breakpoint outputs. These signals are useful for high-speed
synchronization of motion with actuators, sensors, and other parts of the
complete motion system:

• Trigger Input <1..4>—When enabled, an active transition on a
high-speed position capture input causes instantaneous position
capture of the corresponding encoder count value. You can use this
high-speed position capture functionality for applications ranging
from simple position tagging of sensor data to complex camming
systems with advance/retard positioning and registration. An available
7340 position mode is to move an axis Relative to Captured Position.

The polarity of the trigger input is programmable in software as
active-low (inverting) or active-high (non-inverting), rising or falling
edge. You also can use a trigger input as a latching general-purpose
digital input by simply ignoring the captured position.

• Shutdown Input—When enabled in software, the shutdown input
signal can be used to kill all motion by asserting the controller inhibits,
setting the analog outputs to 0 V, and stopping any stepper pulse
generation. To activate shutdown, the signal must transition from a low
to a high state, or rising edge.

• Breakpoint Output <1..4>—A breakpoint output can be programmed
to transition when the associated encoder value equals the breakpoint
position. You can use a breakpoint output to directly control actuators
or as a trigger to synchronize data acquisition or other functions in the
motion control system.

NI 7340 User Manual 5-10 ni.com

Chapter 5 Signal Connections

You can program breakpoints as absolute, modulo, or relative
positions. Breakpoint outputs can be preset to a known state so that the
transition when the breakpoint occurs can be low to high, high to low,
or toggle.

The breakpoint outputs are driven by open-collector TTL buffers that
feature 64 mA sink current capability and built-in 3.3 kΩ pull-up
resistors to +5 V.

You can directly set and reset breakpoint outputs to use them as
general-purpose digital outputs.

Wiring Concerns

Caution Keep trigger input, shutdown input, and breakpoint output signals and their

ground connections wired separately from the motor driver/amplifier signal and encoder
signal connections. Wiring these signals near each other can cause faulty operation.

Caution Excessive input voltages can cause erroneous operation and/or component

failure.

Trigger Input, Shutdown Input, and Breakpoint Output Circuits

Figures 5-5, 5-6, and 5-7 show a simplified schematic diagram of the
circuits used by the trigger inputs, shutdown inputs, and breakpoint outputs
for signal buffering.

Vcc

3.3 kΩ

74FCT244

From the external
connector
trigger pins

© National Instruments Corporation 5-11 NI 7340 User Manual

1 kΩ

1/8 W

DGND

Figure 5-5. Trigger Input Circuit

To the trigger
circuits

Chapter 5 Signal Connections

Vcc

Analog Inputs

3.3 kΩ

From the external
connector
shutdown pin

74FCT244

1 kΩ

1/8 W

DGND

To the shutdown
circuits

Figure 5-6. Shutdown Input Circuit

Vcc

3.3 kΩ

74AS760

To the external
connector
breakpoint pins

From the
breakpoint
circuits

Figure 5-7. Breakpoint Output Circuit

The 7340 has the following ADC input signals:

• Analog Input <1..4>—The 7340 includes an eight-channel
multiplexed, 12-bit ADC capable of measuring ±10 V, ±5 V, 0–10 V,
and 0–5 V inputs. ADC channels 1 through 4 are brought out
externally on the 68-pin motion I/O connector. ADC channels 5
through 8 are connected internally, as shown in Table 5-2. These
signals can be used for ADC test and system diagnostics.

Table 5-2. Internal ADC Channels

ADC Input Signal

5 Filtered +5 V

6 Floating (NC)

7 Analog Reference (7.5 V)

8 Analog Input Ground

NI 7340 User Manual 5-12 ni.com

Chapter 5 Signal Connections

You can configure each ADC channel for motion feedback, simple
A/D conversion, or both.

You can read the digital value of analog voltage on any of the eight
ADC channels of the controller. Table 5-3 shows the range of values
read back and the voltage resolution for each setting. The voltage
resolution is in volts per least significant bit (V/LSB).

Table 5-3. Analog Input Voltage Ranges

Input Range Binary Values Resolution

±10 V –2,048 to 2,047 0.0049 V/LSB

±5 V –2,048 to 2,047 0.0024 V/LSB

0–10 V 0 to 4,095 0.0024 V/LSB

0–5 V 0 to 4,095 0.0012 V/LSB

As indicated in Figure 5-3, when configured as analog feedback, an
analog sensor acts like a limited range absolute position device with a
full-scale position range. You can map any ADC channel as feedback
to any axis.

You can enable and disable individual ADC channels in software.
Disable unused ADC channels for the highest multiplexer scan rate
performance. Properly enabled, the scan rate is high enough to support
analog feedback at the highest PID sample rate.

• Analog Reference—For convenience, 7.5 V (nominal) analog
reference voltage is available. You can use this output as a low-current
supply to sensors that require a stable reference. Refer to Appendix A,

Specifications, for analog reference voltage specifications.

• Analog Input Ground—To help keep digital noise out of the analog
input, a separate return connection is available. Use this reference
ground connection and not Digital Ground (digital I/O reference) or
Analog Output Ground as the reference for the analog inputs.

Wiring Concerns

For proper use of each ADC input channel, the analog signal to be
measured should be connected to the channel input and its ground reference
connected to the Analog Input Ground.

Note The analog reference output is an output signal only and must not connect to an

external reference voltage. Connect the common of the external reference to the Analog
Input Ground pin for proper A/D reference and improved voltage measurement.

© National Instruments Corporation 5-13 NI 7340 User Manual

Chapter 5 Signal Connections

Other Motion I/O Connection

The 7340 provides Host +5 V, which is the internal +5 V supply of the host
computer. It is typically used to detect when the host computer is powered
and to shut down external motion system components when the host
computer is turned off or disconnected from the motion accessory.

Caution The host +5 V signal is limited to <100 mA and should not be used to power any

external devices, except those intended in the host bus monitor circuits on the UMI and
drive products.

NI 7340 User Manual 5-14 ni.com

Digital I/O Connector

All the general-purpose digital I/O lines on the 7340 are available on a
separate 68-pin digital I/O connector. Figure 5-8 shows the pin
assignments for this connector.

Chapter 5 Signal Connections

+5 V

PCLK

Reserved

Reserved

PWM1
Reserved

Reserved

Reserved

PWM2

Port 1:bit 0

Digital Ground

Port 1:bit 3

Port 1:bit 4

Digital Ground

Port 1:bit 7
Port 2:bit 0

Port 2:bit 1

Digital Ground

Digital Ground
Digital Ground

Port 2:bit 6

Port 2:bit 7

Port 3:bit 0

Digital Ground

Port 3:bit 3

Port 3:bit 4

Digital Ground

Port 3:bit 7

Port 4:bit 0

Digital Ground

Port 4:bit 3

Port 4:bit 4

Digital Ground

Port 4:bit 7

135

236

337

438

539

640

741

842

943

10 44

11 45

12 46

13 47

14 48

15 49

16 50

17 51

18 52

19 53

20 54

21 55

22 56

23 57

24 58

25 59

26 60

27 61

28 62

29 63

30 64

31 65

32 66

33 67

34 68

Digital Ground
Digital Ground

Digital Ground

DPull

Digital Ground

Reserved

Digital Ground

Digital Ground

Digital Ground
Port 1:bit 1
Port 1:bit 2

Digital Ground

Port 1:bit 5

Port 1:bit 6

Digital Ground

Digital Ground

Port 2:bit 2

Port 2:bit 3

Port 2:bit 4

Port 2:bit 5
Digital Ground

Digital Ground

Port 3:bit 1

Port 3:bit 2

Digital Ground

Port 3:bit 5

Port 3:bit 6

Digital Ground

Port 4:bit 1
Port 4:bit 2

Digital Ground

Port 4:bit 5

Port 4:bit 6

Digital Ground

Figure 5-8. 68-Pin Digital I/O Connector Pin Assignments

© National Instruments Corporation 5-15 NI 7340 User Manual

Chapter 5 Signal Connections

PWM Features

The 32-bit digital I/O port is configured in hardware as four 8-bit digital I/O
ports. The bits in a port are typically controlled and read with byte-wide
bitmapped commands.

All digital I/O lines have programmable direction and polarity. Each output
circuit can sink and source 24 mA.

The DPull pin controls the state of the input pins at power-up. Connecting
DPull to +5 V or leaving it unconnected configures all pins in all ports for
100 kΩ pull-ups. Connecting DPull to ground configures the ports for
100 kΩ pull-downs.

The 7340 provides two pulse width modulation (PWM) outputs on the
digital I/O connector. The PWM outputs generate periodic waveforms
whose period and duty cycles can be independently controlled through
software commands. The PWM is comparable to a digital representation of
an analog value because the duty cycle is directly proportional to the
expected output value. PWM outputs are typically used for transmitting an
analog value through an optocoupler. A simple lowpass filter turns a PWM
signal back into its corresponding analog value. You have the option to use
the PCLK input instead of the internal source as the clock for the PWM
generators.

Note These signals are configured in software and are in no way associated with the

PID servo control loop. Refer to the NI-Motion User Manual for more information.

RTSI Connector

The physical RTSI bus interface varies depending on the type of 7340
controller.

The PXI-7340 uses the PXI chassis backplane to connect to other
RTSI-capable devices.

The PCI-7340 uses a ribbon cable to connect to other RTSI-capable PCI
devices.

NI 7340 User Manual 5-16 ni.com

RTSI Signal Considerations

The 7340 motion controller allows you to use up to eight RTSI trigger lines
as sources for trigger inputs, or as destinations for breakpoint outputs and
encoder signals. The RTSI trigger lines also can serve as a generic digital
I/O port. The RTSI star trigger line can be used only for a trigger input.
Breakpoint outputs are output-only signals that generate an active-high
pulse of 200 ns duration, as shown in Figure 5-9.

Encoder and Index signals are output-only signals across RTSI that are
the digitally-filtered versions of the raw signals coming into the controller.
If you are using the RTSI bus for trigger inputs or generic digital I/O,
all signals are passed through unaltered.

Chapter 5 Signal Connections

200 ns

Figure 5-9. Breakpoint across RTSI

© National Instruments Corporation 5-17 NI 7340 User Manual

Specifications

This appendix lists the hardware and software performance specifications
for the PXI/PCI-7340. Hardware specifications are typical at 25 °C, unless
otherwise stated.

Servo Performance

PID update rate range............................. 62.5 µs to 5 ms/sample

Maximum PID update rate.............. 62.5 µs/axis

4-axis PID update rate..................... 250 µs total

Multi-axis synchronization .................... <1 update sample

Position accuracy

Encoder feedback............................ ±1 quadrature count

Analog feedback ............................. ±1 LSB

Double-buffered trajectory parameters

Absolute position range .................. ±2

Maximum relative move size.......... ±2

Velocity range................................. 1 to ±20,000,000 counts/s

Acceleration/deceleration

S-Curve time range ......................... 1 to 32,767 samples

Following error range ..................... 1 to 32,767 counts and disabled

Gear ratio ........................................ ±32,767:1 to ±1:32,767

31

counts

31

counts

1

.............. ±512,000,000 counts/s

A

2

Servo control loop modes ......................PID, PIVff, S-Curve, Dual Loop

PID (Kp, Ki, and Kd) gains ............ 0 to 32,767

Integration limit (Ilim) .................... 0 to 32,767

Derivative sample period (Td) ........ 1 to 63 samples

Feedforward (Aff, Vff) gains.......... 0 to 32,767

Velocity feedback (Kv) gain........... 0 to 32,767

1

Assumes a PID update rate of 250 µs and a 2,000-count encoder.

© National Instruments Corporation A-1 NI 7340 User Manual

Appendix A Specifications

Servo command analog outputs

Stepper Performance

Trajectory update rate range ...................62.5 to 500 µs/sample

Multi-axis synchronization .....................<1 update sample

Position accuracy

Voltage range...................................±10 V

Resolution........................................16 bits (0.000305 V/LSB)

Programmable torque (velocity) limits

Positive limit ............................±10 V (–32,768 to +32,767)

Negative limit...........................±10 V (–32,768 to +32,767)

Programmable offset .......................±10 V (–32,768 to +32,767)

Maximum update rate......................62.5 µs/axis

4-axis update rate.............................250 µs total

Open-loop stepper ...........................1 full, half, or microstep

Encoder feedback ............................±1 quadrature count

Analog feedback..............................±1 LSB

Double-buffered trajectory parameters

Position range ..................................±2

Maximum relative move size ..........±2

31

steps

31

steps

Velocity range .................................1 to 4,000,000 steps/s

Acceleration/deceleration

1

...............±512,000,000 counts/s

2

S-Curve time range..........................1 to 32,767 samples

Following error range ......................0 to 32,767 counts

Gear ratio .........................................±32,767:1 to ±1:32,767

Stepper outputs

Maximum pulse rate........................4 MHz (full, half, and microstep)

Minimum pulse width......................120 ns at 4 MHz

Step output mode.............................Step and direction or CW/CCW

1

Assumes a PID update rate of 250 µs and a 2,000-count encoder.

NI 7340 User Manual A-2 ni.com

System Safety

Appendix A Specifications

Voltage range.................................. 0 to 5 V

Output low voltage .................. <0.6 V at 64 mA sink

Output high voltage ................. Open collector with built-in

3.3 kΩ pull-up to +5 V

Polarity............................................ Programmable, active-high

or active-low

Watchdog timer function .......................Resets board to startup state

Watchdog timeout........................... 63 ms

Shutdown input

Voltage range.................................. 0 to 5 V

Input low voltage .....................0.8 V

Input high voltage .................... 2 V

Polarity..................................... Rising edge

Control ............................................ Disable all axes and

command outputs

Motion I/O

Encoder inputs........................................ Quadrature, incremental,

single-ended

Maximum count rate....................... 20 MHz

Minimum pulse width..................... Programmable; depends

on digital filter settings

Voltage range.................................. 0 to 5 V

Input low voltage .....................0.8 V

Input high voltage .................... 2 V

Minimum index pulse width ........... Programmable; depends

on digital filter settings

Forward, reverse, and home inputs

Number of inputs ............................ 12 (3 per axis)

Voltage range.................................. 0 to 5 V

Input low voltage .....................0.8 V

Input high voltage .................... 2 V

Polarity............................................ Programmable, active-high

or active-low

© National Instruments Corporation A-3 NI 7340 User Manual

Appendix A Specifications

Minimum pulse width......................1 ms with filter enabled;

60 ns without filter enabled

Control.............................................Individual enable/disable, stop on

input, prevent motion, Find Home

Trigger inputs

Number of inputs.............................4 (Encoders 1 through 4)

Voltage range...................................0 to 5 V

Input low voltage......................0.8 V

Input high voltage.....................2 V

Polarity ............................................Programmable, active-high

or active-low

Minimum pulse width......................100 ns

Capture latency................................<100 ns

Capture accuracy .............................1 count

Maximum repetitive capture rate.....100 Hz

Breakpoint outputs

Number of outputs...........................4 (Encoders 1 through 4)

Voltage range...................................0 to 5 V

Output low voltage ...................<0.6 V at 64 mA sink

Output high voltage..................Open collector with built-in

3.3 kΩ pull-up to +5 V

Polarity ............................................Programmable, active-high

or active-low

Maximum repetitive

breakpoint rate .................................100 Hz

Inhibit/enable output

Number of outputs...........................4 (1 per-axis)

Voltage range...................................0 to 5 V

Output low voltage ...................<0.6 V at 64 mA sink

Output high voltage..................Open collector with built-in

3.3 kΩ pull-up to +5 V

Polarity ............................................Programmable, active-high

or active-low

Control.............................................MustOn/MustOff or

automatic when axis off

NI 7340 User Manual A-4 ni.com

Appendix A Specifications

Analog inputs

Number of inputs ............................ 8, multiplexed, single ended

Number for user signals........... 4

Number for system diagnostics... 4

Voltage range (programmable) ....... ±10 V, ±5 V, 0–10 V, 0–5 V

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

Input resistance ...............................10 kΩ min

Resolution ....................................... 12 bits, no missing codes

Monotonic....................................... Guaranteed

Multiplexor scan rate ...................... 25 µs/enabled channel

Analog outputs

Number of outputs .......................... 4, single ended

Output coupling .............................. DC

Voltage range.................................. ±10 V

Output current ................................. ±5 mA

Resolution ....................................... 16 bits, no missing codes

Monotonic....................................... Guaranteed

Analog reference output.................. 7.5 V (nominal) @ 5 mA

Digital I/O

Ports .......................................................4, 8-bit ports

Line direction.................................. Individual bit programmable

Inputs

Voltage range.................................. 0 to 5 V

Input low voltage ..................... 0.8 V

Input high voltage.................... 2.0 V

Polarity............................................ Programmable, active-high

or active-low

Outputs

Voltage range.................................. 0 to 5 V

Output low voltage .................. <0.45 V at 24 mA sink

Output high voltage ................. >2.4 V at 24 mA source

Polarity............................................ Programmable, active-high

or active-low

© National Instruments Corporation A-5 NI 7340 User Manual

Appendix A Specifications

PWM outputs

Number of PWM outputs .........2

Maximum PWM frequency......50 kHz

Resolution.................................8-bit

Duty cycle range.......................0 to (255/256)%

Clock sources ...........................Internal or external

RTSI

Trigger lines............................................8

Maximum Power Requirements

+5 V (±3%).............................................1 A

+12 V (±3%)...........................................30 mA

–12 V (±3%) ...........................................30 mA

Power consumption ................................5.7 W

Physical

Dimensions (Not Including Connectors)

PXI-7340 ................................................16 × 10 cm (6.3 × 3.9 in.)

PCI-7340.................................................17.5 × 9.9 cm (6.9 × 3.9 in.)

Connectors

Motion I/O connector .............................68-pin female high-density

VHDCI type

32-bit digital I/O connector ....................68-pin female high-density

VHDCI type

Weight

PXI-7340 ................................................170 g (6 oz)

PCI-7340.................................................113 g (4 oz)

NI 7340 User Manual A-6 ni.com

Maximum Working Voltage

Channel-to-earth..................................... 12 V, Installation Category I

Channel-to-channel ................................22 V, Installation Category I

Caution These values represent the maximum allowable voltage between any accessible

signals on the controller. To determine the acceptable voltage range for a particular signal,
refer to the individual signal specifications.

Environment

Operating temperature............................ 0 to 55 °C

Storage temperature ............................... –20 to 70 °C

Humidity ................................................ 10 to 90% RH, noncondensing

Maximum altitude .................................. 2,000 m

Appendix A Specifications

(signal voltage plus
common-mode voltage)

(signal voltage plus
common-mode voltage)

Pollution Degree .................................... 2

Safety

This product is designed to meet the requirements of the following
standards of safety for electrical equipment for measurement, control,
and laboratory use:

• IEC 61010-1, EN 61010-1

• UL 3111-1, UL 61010B-1

• CAN/CSA C22.2 No. 1010.1

Note For UL and other safety certifications, refer to the product label, or visit

ni.com/hardref.nsf, search by model number or product line, and click the

appropriate link in the Certification column.

© National Instruments Corporation A-7 NI 7340 User Manual

Appendix A Specifications

Electromagnetic Compatibility

Emissions................................................EN 55011 Class A at 10 m

Immunity ................................................EN 61326:1997 + A2:2001,

EMC/EMI ...............................................CE, C-Tick, and FCC Part 15

Note For EMC compliance, you must operate this device with shielded cabling.

CE Compliance

This product meets the essential requirements of applicable European
Directives, as amended for CE marking, as follows:

Low-Voltage Directive (safety)..............73/23/EEC

Electromagnetic Compatibility

Directive (EMC) .....................................89/336/EEC

FCC Part 15A above 1 GHz

Table 1

(Class A) Compliant

Note Refer to the Declaration of Conformity (DoC) for this product for any additional

regulatory compliance information. To obtain the DoC for this product, visit

ni.com/hardref.nsf, search by model number or product line, and click the

appropriate link in the Certification column.

NI 7340 User Manual A-8 ni.com

Cable Connector Descriptions

This appendix describes the connector pinout for the cables that connect
to the PXI/PCI-7340.

Figures B-1 and B-2 show the pin assignments for the stepper and servo
50-pin motion connectors. These connectors are available when you use
the SH68-C68-S shielded cable assembly and the 68M-50F step/servo
bulkhead cable adapter.

B

Axis 1 Dir (CCW)

Digital Ground
Digital Ground

Axis 1 Home Switch

Trigger/Breakpoint 1

Axis 1 Inhibit

Axis 2 Dir (CCW)

Digital Ground

Digital Ground

Axis 2 Home Switch

Trigger/Breakpoint 2

Axis 2 Inhibit

Axis 3 Dir (CCW)

Digital Ground

Digital Ground

Axis 3 Home Switch

Trigger/Breakpoint 3

Axis 3 Inhibit

Axis 4 Dir (CCW)

Digital Ground

Digital Ground

Axis 4 Home Switch

Trigger/Breakpoint 4

Axis 4 Inhibit

Digital Ground

12

34

56

78

910

11 12

13 14

15 16

17 18

19 20

21 22

23 24

25 26

27 28

29 30

31 32

33 34

35 36

37 38

39 40

41 42

43 44

45 46

47 48

49 50

Axis 1 Step (CW)
Axis 1 Encoder Phase A

Axis 1 Encoder Phase B

Axis 1 Encoder Index

Axis 1 Forward Limit Switch

Axis 1 Reverse Limit Switch

Axis 2 Step (CW)

Axis 2 Encoder Phase A
Axis 2 Encoder Phase B

Axis 2 Encoder Index

Axis 2 Forward Limit Switch

Axis 2 Reverse Limit Switch

Axis 3 Step (CW)

Axis 3 Encoder Phase A

Axis 3 Encoder Phase B

Axis 3 Encoder Index

Axis 3 Forward Limit Switch

Axis 3 Reverse Limit Switch

Axis 4 Step (CW)

Axis 4 Encoder Phase A
Axis 4 Encoder Phase B

Axis 4 Encoder Index

Axis 4 Forward Limit Switch

Axis 4 Reverse Limit Switch

Host +5 V

Figure B-1. 50-Pin Stepper Connector Pin Assignment

© National Instruments Corporation B-1 NI 7340 User Manual

Appendix B Cable Connector Descriptions

Analog Output Ground

Digital Ground
Digital Ground

Axis 1 Home Switch

Trigger/Breakpoint 1

Axis 1 Inhibit

Analog Output Ground

Digital Ground

Digital Ground

Axis 2 Home Switch

Trigger/Breakpoint 2

Axis 2 Inhibit

Analog Output Ground

Digital Ground

Digital Ground

Axis 3 Home Switch

Trigger/Breakpoint 3

Axis 3 Inhibit

Analog Output Ground

Digital Ground

Digital Ground

Axis 4 Home Switch

Trigger/Breakpoint 4

Axis 4 Inhibit

Digital Ground

12

34

56

78

910

11 12

13 14

15 16

17 18

19 20

21 22

23 24

25 26

27 28

29 30

31 32

33 34

35 36

37 38

39 40

41 42

43 44

45 46

47 48

49 50

Analog Output 1
Axis 1 Encoder Phase A

Axis 1 Encoder Phase B

Axis 1 Encoder Index

Axis 1 Forward Limit Switch

Axis 1 Reverse Limit Switch

Analog Output 2

Axis 2 Encoder Phase A

Axis 2 Encoder Phase B

Axis 2 Encoder Index

Axis 2 Forward Limit Switch

Axis 2 Reverse Limit Switch

Analog Output 3

Axis 3 Encoder Phase A

Axis 3 Encoder Phase B

Axis 3 Encoder Index

Axis 3 Forward Limit Switch

Axis 3 Reverse Limit Switch

Analog Output 4

Axis 4 Encoder Phase A
Axis 4 Encoder Phase B

Axis 4 Encoder Index

Axis 4 Forward Limit Switch

Axis 4 Reverse Limit Switch

Host +5 V

Figure B-2. 50-Pin Servo Connector Pin Assignment

NI 7340 User Manual B-2 ni.com

Technical Support and
Professional Services

Visit the following sections of the National Instruments Web site at

ni.com for technical support and professional services:

• Support—Online technical support resources include the following:

– Self-Help Resources—For immediate answers and solutions,

visit our extensive library of technical support resources available
in English, Japanese, and Spanish at
resources are available for most products at no cost to registered
users and include software drivers and updates, a KnowledgeBase,
product manuals, step-by-step troubleshooting wizards,
conformity documentation, example code, tutorials and
application notes, instrument drivers, discussion forums,
a measurement glossary, and so on.

– Assisted Support Options—Contact NI engineers and other

measurement and automation professionals by visiting

ni.com/support. Our online system helps you define your

question and connects you to the experts by phone, discussion
forum, or email.

• Training—Visit

and interactive CDs. You also can register for instructor-led, hands-on
courses at locations around the world.

• System Integration—If you have time constraints, limited in-house

technical resources, or other project challenges, NI Alliance Program
members can help. To learn more, call your local NI office or visit

ni.com/alliance.

• Declaration of Conformity (DoC)—A DoC is our claim of

compliance with the Council of the European Communities using
the manufacturer’s declaration of conformity. This system affords
the user protection for electronic compatibility (EMC) and product
safety. You can obtain the DoC for your product by visiting

ni.com/hardref.nsf.

ni.com/training for self-paced tutorials, videos,

C

ni.com/support. These

© National Instruments Corporation C-1 NI 7340 User Manual

Appendix C Technical Support and Professional Services

If you searched ni.com and could not find the answers you need, contact
your local office or NI corporate headquarters. Phone numbers for our
worldwide offices are listed at the front of this manual. You also can visit
the Worldwide Offices section of
office Web sites, which provide up-to-date contact information, support
phone numbers, email addresses, and current events.

ni.com/niglobal to access the branch

NI 7340 User Manual C-2 ni.com

Glossary

Symbol Prefix Value

µ micro 10

m milli 10

Mmega10

Numbers/Symbols

/per

± plus or minus

+ positive of, or plus

– negative of, or minus

+5 V +5 VDC source signal

A

–6

–3

6

A amperes

A/D analog-to-digital

absolute mode treat the target position loaded as position relative to zero (0) while making

a move

absolute position position relative to zero

acceleration/
deceleration

active-high signal is active when its value goes high (1)

active-low signal is active when its value goes low (0)

ADC analog-to-digital converter

© National Instruments Corporation G-1 NI 7340 User Manual

measurement of the change in velocity as a function of time. Acceleration
and deceleration describes the period when velocity is changing from one
value to another.

Glossary

address character code that identifies a specific location (or series of locations)

in memory or on a host PC bus system

amplifier drive that delivers power to operate the motor in response to low level

control signals. In general, the amplifier is designed to operate with a
particular motor type—for example, you cannot use a stepper drive to
operate a DC brush motor

Analog Input <1..4> 12-bit analog ADC input

Analog Output <1..4> 16-bit DAC voltage output

API application programming interface

axis unit that controls a motor or any similar motion or control device

Axis <1..4> Forward
Limit Input

Axis <1..4> Home
Input

Axis <1..4> Inhibit

Axis <1..4> Reverse
Limit Input

axis 1 through 4 forward/clockwise limit switch

axis 1 through 4 home input

axis 1 through 4 inhibit output

axis 1 through 4 reverse/counter-clockwise limit input

B

b bit—one binary digit, either 0 or 1

base address memory address that serves as the starting address for programmable or

I/O bus registers. All other addresses are located by adding to the base
address.

binary number system with a base of 2

buffer temporary storage for acquired or generated data (software)

bus group of conductors that interconnect individual circuitry in a computer.

Typically, a bus is the expansion vehicle to which I/O or other devices are
connected.

NI 7340 User Manual G-2 ni.com

Glossary

byte eight related bits of data, an eight-bit binary number. Also used to denote

the amount of memory required to store one byte of data.

C

CCW counter-clockwise—implies direction of rotation of the motor

closed-loop motion system that uses a feedback device to provide position and velocity

data for status reporting and accurately controlling position and velocity

common reference signal for digital I/O

CPU central processing unit

crosstalk unwanted signal on one channel due to an input on a different channel

CSR Communications Status Register

CW clockwise—implies direction of motor rotation

D

D/A digital-to-analog

DAC Digital-to-Analog Converter

DC direct current

dedicated assigned to a particular function

DGND digital ground signal

digital I/O port group of digital input/output signals

DIP dual inline package

DLL dynamic link library—provides the API for the motion control boards

drivers software that communicates commands to control a specific motion control

board

DSP Digital Signal Processor

© National Instruments Corporation G-3 NI 7340 User Manual

Glossary

E

encoder device that translates mechanical motion into electrical signals; used for

monitoring position or velocity in a closed-loop system

encoder resolution number of encoder lines between consecutive encoder indexes (marker or

Z-bit). If the encoder does not have an index output, the encoder resolution
can be referred to as lines per revolution.

F

f farad

FIFO first in, first out—data buffering technique that functions like a shift register

where the oldest values (first in) come out first

filter parameters indicates the control loop parameter gains (PID gains) for a given axis

filtering type of signal conditioning that filters unwanted signals from the signal

being measured

flash ROM type of electrically reprogrammable read-only memory

following error
trip point

FPGA Field Programmable Gate Array

freewheel condition of a motor when power is de-energized and the motor shaft is free

full-step full-step mode of a stepper motor—for a two phase motor this is done by

difference between the instantaneous commanded trajectory position and
the feedback position

to turn with only frictional forces to impede it

energizing both windings or phases simultaneously

G

Gnd ground

GND ground

NI 7340 User Manual G-4 ni.com

Glossary

H

half-step mode of a stepper motor—for a two phase motor this is done by alternately

energizing two windings and then only one. In half step mode, alternate
steps are strong and weak but there is significant improvement in low-speed
smoothness over the full-step mode.

hex hexadecimal

home switch (input) physical position determined by the mechanical system or designer as the

reference location for system initialization. Frequently, the home position is
also regarded as the zero position in an absolute position frame of reference.

host computer computer into which the motion control board is plugged

I

I/O input/output—the transfer of data to and from a computer system involving

communications channels, operator interface devices, and/or motion
control interfaces

ID identification

in. inches

index marker between consecutive encoder revolutions

inverting polarity of a switch (limit switch, home switch, and so on) in active state.

If these switches are active-low they are said to have inverting polarity.

IRQ interrupt request

K

k kilo—the standard metric prefix for 1,000, or 103, used with units of

measure such as volts, hertz, and meters

K kilo—the prefix for 1,024, or 2

computer memory

10

, used with B in quantifying data or

© National Instruments Corporation G-5 NI 7340 User Manual

Glossary

L

LIFO last in, last out—data buffering technique where the newest values (last in)

come out first

limit switch/
end-of-travel position
(input)

sensors that alert the control electronics that physical end of travel is being
approached and that the motion should stop

M

m meters

MCS Move Complete Status

microstep proportional control of energy in the coils of a Stepper Motor that

allows the motor to move to or stop at locations other than the fixed
magnetic/mechanical pole positions determined by the motor
specifications. This capability facilitates the subdivision of full mechanical
steps on a stepper motor into finer microstep locations that greatly smooth
motor running operation and increase the resolution or number of discrete
positions that a stepper motor can attain in each revolution.

modulo position treat the position as within the range of total quadrature counts per

revolution for an axis

N

noise undesirable electrical signal—noise comes from external sources such as

the AC power line, motors, generators, transformers, fluorescent lights,
soldering irons, CRT displays, computers, electrical storms, welders, radio
transmitters, and internal sources such as semiconductors, resistors, and
capacitors. Noise corrupts signals you are trying to send or receive.

noninverting polarity of a switch (limit switch, home switch, and so on) in active state.

If these switches are active-high, they are said to have non-inverting
polarity.

NI 7340 User Manual G-6 ni.com

Glossary

O

open-loop refers to a motion control system where no external sensors (feedback

devices) are used to provide position or velocity correction signals

P

PCI Peripheral Component Interconnect—a high-performance expansion bus

architecture originally developed by Intel to replace ISA and EISA. It is
achieving widespread acceptance as a standard for PCs and workstations;
it offers a theoretical maximum transfer rate of 132 MB/s.

PID proportional-integral-derivative control loop

PIVff proportional-integral-velocity feed forward

port (1) a communications connection on a computer or a remote controller;

(2) a digital port, which consists of eight lines of digital input and/or output

position breakpoint position breakpoint for an encoder can be set in absolute or relative

quadrature counts. When the encoder reaches a position breakpoint,
the associated breakpoint output immediately transitions.

power cycling turning the host computer off and then back on, which causes a reset of

the motion control board

PWM Pulse Width Modulation—a method of controlling the average current in

a motor phase winding by varying the on-time (duty cycle) of transistor
switches

PXI PCI eXtensions for Instrumentation

Q

quadrature counts encoder line resolution times four

R

RAM random-access memory

relative breakpoint sets the position breakpoint for an encoder in relative quadrature counts

© National Instruments Corporation G-7 NI 7340 User Manual

Glossary

relative position destination or target position for motion specified with respect to the

current location regardless of its value

relative position mode position relative to current position

ribbon cable flat cable in which the conductors are side by side

RPM revolutions per minute—units for velocity

RPSPS or RPS/S revolutions per second squared—units for acceleration and deceleration

RTR Ready to Receive

S

s seconds

servo specifies an axis that controls a servo motor

stepper specifies an axis that controls a stepper motor

stepper <1..4>
Dir (CCW)

stepper <1..4>
Step (CW)

direction output or counter-clockwise direction control

stepper pulse output or clockwise direction control

T

toggle changing state from high to low, back to high, and so on

torque force tending to produce rotation

trapezoidal profile typical motion trajectory, where a motor accelerates up to the programmed

velocity using the programmed acceleration, traverses at the programmed
velocity, then decelerates at the programmed acceleration to the target
position

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

TTL transistor-transistor logic

NI 7340 User Manual G-8 ni.com

V

Vvolts

Glossary

V

CC

velocity mode move the axis continuously at the specified velocity

positive voltage supply

W

watchdog timer task that shuts down (resets) the motion control board if any serious

error occurs

word standard number of bits that a processor or memory manipulates at

one time, typically 8-, 16-, or 32-bit

© National Instruments Corporation G-9 NI 7340 User Manual

Index

Numerics

68-pin

digital I/O connector, 3-3
motion I/O connector, 3-3

7340

analog feedback, 4-2
axes, 4-3
breakpoint outputs, 5-10
configuring, 2-1
embedded operating system, 4-2
encoder signals, 5-7
features, 1-1
flash memory, 4-3
general-purpose digital I/O lines, 5-15
hardware, 1-1

architecture, 4-1
home inputs, 5-5
input and output signal connections, 5-1
installing software, 2-1
introduction, 1-1
limit inputs, 5-5
motion

I/O connections, 1-4

I/O connector, 5-1

resources, 4-4
National Instruments application

software, 1-3
overview, 3-1
pulse width modulation (PWM)

outputs, 5-16
shutdown input, 5-10
software programming choices, 1-3
trajectory generators, 4-2
trigger inputs, 5-10
user connectors, 3-3
using RTSI, 1-2

A

Analog Input <1..4>, 5-12
Analog Input Ground, 5-13
Analog Output <1..4>, 5-4
Analog Output Ground, 5-4
Analog Reference, 5-13
analog signals, wiring, 5-13
axes, 4-3

secondary

feedback resources, 4-4
output resources, 4-4

Axis <1..4>

Forward Limit Input, 5-5
Home Input, 5-5
Inhibit, 5-5
Reverse Limit Input, 5-5
Step (CW) and Dir (CCW), 5-4

B

breakpoint

concepts, 4-5
examples, 5-17

breakpoint output

circuit, 5-12

signals, wiring, 5-11
Breakpoint Output <1..4>, 5-10
buffers, 4-5

C

command buffer, 4-5
communications status register (CSR), 4-5
communications, host, 4-5
connectors

68-pin

digital I/O, 3-3, 5-1

© National Instruments Corporation I-1 NI 7340 User Manual

Index

motion I/O, 3-3, 5-1
motion I/O, 5-1
RTSI, 3-3, 5-1

conventions used in the manual, vii

D

Declaration of Conformity (NI resources), C-1
diagnostic tools (NI resources), C-1
documentation

conventions used in manual, vii
NI resources, C-1
related documentation, viii

drivers (NI resources), C-1

E

Encoder <1..4>

Index, 5-8
Phase A/Phase B, 5-7

encoder signals

ground connections, 5-9

examples (NI resources), C-1

F

functional overview

buffers, 4-5
host communications, 4-5
onboard programs, 4-5

G

ground connections

encoder signals, 5-9
wiring

breakpoint outputs, 5-11

shutdown input, 5-11

trigger inputs, 5-11

H

help, technical support, C-1
high-speed capture, 4-5
home inputs

circuit, 5-7

ground connections, 5-6
Host +5 V, 5-14
host communications, 4-5

I

installing

hardware, 2-4

installation category descriptions, 2-3

software, 2-1
instrument drivers (NI resources), C-1

K

KnowledgeBase, C-1

L

limit input circuit, 5-7
limit inputs, ground connections, 5-6

M

memory, buffer storage, 4-5
motion I/O

connector

pin assignments, 5-2
signal descriptions, 5-3

N

National Instruments support and

services, C-1

NI support and services, C-1

NI 7340 User Manual I-2 ni.com

Index

O

onboard programs, 4-5

P

pin assignments

68-pin digital I/O connector, 5-15

programming examples (NI resources), C-1

R

related documentation, viii
return data buffer (RDB), 4-5
RTSI

breakpoint across RTSI (figure), 5-17
connector, 3-3, 5-16
signal considerations, 5-17

S

safety information, 2-1
Shutdown Input, 5-10
software (NI resources), C-1
software, onboard programs, 4-5
support, technical, C-1

T

technical support, C-1
training (NI resources), C-1
Trigger Input <1..4>, 5-10
trigger input circuit, 5-11
trigger inputs, wiring, 5-11
troubleshooting (NI resources), C-1

W

Web resources, C-1
wiring, analog signals, 5-13

© National Instruments Corporation I-3 NI 7340 User Manual