National Instruments NI PXIe-6672 User Manual

PXI Express

NI PXIe-6672 User Manual

Timing and Synchronization Module for PXI Express

NI PXIe-6672 User Manual

June 2008
372185F-01

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Important Information

Warranty

The NI PXIe-6672 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 instruc tions 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
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Contents

About This Manual

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

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

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

Chapter 1
Introduction

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

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

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

Safety Information .........................................................................................................1-3

Chapter 2
Installing and Configuring

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

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

Configuring the Module.................................................................................................2-2

Chapter 3
Hardware Overview

NI PXIe-6672 Front Panel .............................................................................................3-3

Access LED .....................................................................................................3-4

Active LED......................................................................................................3-4

Connectors.......................................................................................................3-5

Hardware Features .........................................................................................................3-5

Clock Generation ...........................................................................................................3-7

Direct Digital Synthesis (DDS) .......................................................................3-7

PXI_CLK10 and TCXO..................................................................................3-8

Routing Signals..............................................................................................................3-9

Determining Sources and Destinations ...........................................................3-11

Using Front Panel PFIs As Inputs.....................................................3-12

Using Front Panel PFIs As Outputs ..................................................3-13

Using the PXI Triggers .....................................................................3-14

Using the PXI Star Triggers..............................................................3-15

© National Instruments Corporation v NI PXIe-6672 User Manual

Contents

Choosing the Type of Routing ........................................................................ 3-15

Asynchronous Routing ..................................................................... 3-16

Synchronous Routing ....................................................................... 3-17

Generating a Single Pulse (Global Software Trigger) .................................... 3-18

Using the PXI_CLK10 PLL .......................................................................................... 3-19

Chapter 4
Calibration

Factory Calibration........................................................................................................ 4-1

TCXO Frequency............................................................................................ 4-1

PXI_CLK10 Phase.......................................................................................... 4-1

DDS Start Trigger Phase................................................................................. 4-1

DDS Initial Phase............................................................................................ 4-2

Additional Information.................................................................................................. 4-2

Appendix A
Specifications

Appendix B
Technical Support and Professional Services

Glossary

Index

NI PXIe-6672 User Manual vi ni.com

About This Manual

Thank you for purchasing the National Instruments NI PXIe-6672 Timing
and Synchronization Module. The NI PXIe-6672 enables you to pass
PXI timing and trigger signals between two or more PXI Express chassis.
The NI PXIe-6672 can generate and route clock signals between devices in
multiple chassis, providing a method to synchronize multiple devices
in a multichassis PXI Express system.

This manual describes the electrical and mechanical aspects of the
NI PXIe-6672 and contains information concerning its operation and
programming.

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,
AO <3. .0>.

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

to a final action. The sequence File»Page Setup»Options directs you to
pull down the File menu, select the Page Setup item, and select Options
from the last dialog box.

This icon denotes a tip, which alerts you to advisory information.

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

This icon denotes a caution, which advises you of precautions to take to
avoid injury, data loss, or a system crash. When this symbol is marked on
the product, refer to the Safety Information section of Chapter 1,

Introduction, for precautions to take.

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

as menu items and dialog box options. Bold text also denotes parameter
names and hardware labels.

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

to a key concept. Italic text also denotes text that is a placeholder for a word
or value that you must supply.

© National Instruments Corporation vii NI PXIe-6672 User Manual

About This Manual

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.

NI PXIe-6672 This phrase refers to the NI PXIe-6672 module for the PXI Express bus.

National Instruments Documentation

The NI PXIe-6672 User Manual is one piece of the documentation set for
your measurement system. You could have any of several other documents
describing your hardware and software. Use the documentation you have
as follows:

• Measurement hardware documentation—This documentation contains
detailed information about the measurement hardware that plugs into
or is connected to the computer. Use this documentation for hardware
installation and configuration instructions, specifications about the
measurement hardware, and application hints.

• Software documentation—Refer to the NI-Sync User Manual,
available at

ni.com/manuals.

You can download NI documentation from

ni.com/manuals.

Related Documentation

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

• PICMG 2.0 R3.0, CompactPCI Core Specification, available from
PICMG at

• PXI-5 PXI Express Hardware Specification, Revision 1.0, available
from

• NI-VISA User Manual, available from ni.com/manuals

• NI-VISA Help, included with the NI-VISA software

• NI-Sync User Manual, available from

NI PXIe-6672 User Manual viii ni.com

www.picmg.org

www.pxisa.org

ni.com/manuals

Introduction

The NI PXIe-6672 timing and triggering module enables you to pass
PXI timing signals between two or more PXI Express chassis. The
NI PXIe-6672 module generates and routes clock signals between devices
in multiple chassis, providing a method for synchronizing multiple devices
in a PXI Express system.

What You Need to Get Started

To set up and use the NI PXIe-6672, you need the following items:

❑ NI PXIe-6672 Timing and Triggering Module

❑ NI PXIe-6672 User Manual

❑ NI-Sync CD

❑ An Application Development Environment such as:

–LabVIEW

– LabWindows

– Microsoft Visual C++ (MSVC)

™

/CVI

1

™

❑ PXI Express chassis

❑ PXI Express embedded controller or a desktop computer connected to

the PXI Express chassis using MXI-Express hardware

For information on using the driver software for synchronization, refer
to the NI-Sync User Manual, which you can find on the NI-Sync CD or
download from

© National Instruments Corporation 1-1 NI PXIe-6672 User Manual

ni.com/manuals.

Chapter 1 Introduction

Unpacking

Caution Never touch the exposed pins of connectors.

The NI PXIe-6672 is shipped in an antistatic package to prevent
electrostatic damage to the module. Electrostatic discharge (ESD)
can damage several components on the module.

To avoid such damage in handling the module, take the following
precautions:

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

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

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

Store the NI PXIe-6672 in the antistatic envelope when not in use.

Software Programming Choices

When programming the NI PXIe-6672, you can use NI application
development environment (ADE) software such as LabVIEW or
LabWindows/CVI, or you can use other ADEs such as Visual C/C++.

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

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

NI PXIe-6672 User Manual 1-2 ni.com

Safety Information

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

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

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

Do not operate the product in an explosive atmosphere or where there may
be flammable gases or fumes. If you must operate the product in such an
environment, it must be in a suitably rated enclosure.

If you need to clean the product, use a soft, nonmetallic brush. The product
must be completely dry and free from contaminants before you return it to
service.

Chapter 1 Introduction

Operate the product only at or below Pollution Degree 2. Pollution is
foreign matter in a solid, liquid, or gaseous state that can reduce dielectric
strength or surface resistivity. The following is a description of pollution
degrees:

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

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

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

You must insulate signal connections for the maximum voltage for which
the product is rated. Do not exceed the maximum ratings for the product.
Do not install wiring while the product is live with electrical signals. Do not
remove or add connector blocks when power is connected to the system.
Avoid contact between your body and the connector block signal when hot
swapping modules. Remove power from signal lines before connecting
them to or disconnecting them from the product.

© National Instruments Corporation 1-3 NI PXIe-6672 User Manual

Chapter 1 Introduction

Operate the product at or below the installation category1 marked on the
hardware label. Measurement circuits are subjected to working voltages

2

and transient stresses (overvoltage) from the circuit to which they are
connected during measurement or test. Installation categories establish
standard impulse withstand voltage levels that commonly occur in
electrical distribution systems. The following is a description of installation
categories:

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

3

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 (for example, 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
meters and measurements on primary overcurrent protection devices
and on ripple control units.

1

Installation categories, also referred to as measurement categories, are 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

MAINS is defined as a hazardous live electrical supply system that powers equipment. Suitably rated measuring circuits may
be connected to the MAINS for measuring purposes.

NI PXIe-6672 User Manual 1-4 ni.com

Installing and Configuring

This chapter describes how to install the NI PXIe-6672 hardware and
software and how to configure the device.

Installing the Software

Refer to the readme.htm file that accompanies the NI-Sync CD for
software installation directions.

Note Be sure to install the driver software before installing the NI PXIe-6672 hardware.

Installing the Hardware

The following are general installation instructions. Consult the chassis
user manual or technical reference manual for specific instructions and
warnings about installing new modules.

1. Power off and unplug the chassis.

2. Locate the System Timing Slot in your chassis. It is marked by either
a square glyph shown in Figure 2-1, or a square glyph with a circle
inside of it, as shown in Figure 2-2.

2

Figure 2-1. System Timing Device Slot Indicator Glyph without Circle

Figure 2-2. System Timing Device Slot Indicator Glyph on the NI PXIe-1062Q Chassis

© National Instruments Corporation 2-1 NI PXIe-6672 User Manual

Chapter 2 Installing and Configuring

Note The slot number printed on the glyph may vary from chassis to chassis.

The circle inside of the square indicates that the slot may also be used as a PXI Express
peripheral slot.

3. Remove the filler panel for the PXI slot you located in step 2.

4. Ground yourself using a grounding strap or by holding a grounded

5. Remove any packing material from the front panel screws and

6. Insert the NI PXIe-6672 into the PXI Express slot. Use the

7. Screw the front panel of the device to the front panel mounting rail of

8. Visually verify the installation. Make sure the module is not touching

9. Plug in and power on the chassis.

The NI PXIe-6672 is now installed.

object. Follow the ESD protection precautions described in the

Unpacking section of Chapter 1, Introduction.

backplane connectors.

injector/ejector handle to fully insert the module into the chassis.

the chassis.

other modules or components and is fully inserted into the slot.

Configuring the Module

The NI PXIe-6672 is completely software configurable. The system
software automatically allocates all module resources.

The two LEDs on the front panel provide information about module status.
The front panel description sections of Chapter 3, Hardware Overview,
describe the LEDs in greater detail.

NI PXIe-6672 User Manual 2-2 ni.com

Hardware Overview

This chapter presents an overview of the hardware functions of
the NI PXIe-6672. Figure 3-1 provides a functional overview of
the NI PXIe-6672 hardware.

3

© National Instruments Corporation 3-1 NI PXIe-6672 User Manual

Chapter 3 Hardware Overview

CLKIN

CLKOUT

PFI 0

PFI 1

PFI 2

PFI 3

PFI 4

PFI 5

AC Coupled

Clock Detector

TCXO

Clock

Driver/

Comparator

PFI 0

Threshold

DAC

Driver/

Comparator

PFI 1

Threshold

DAC

Driver/

Comparator

PFI 2

Threshold

DAC

Driver/

Comparator

PFI 3

Threshold

DAC

Driver/

Comparator

PFI 4

Threshold

DAC

Driver/

Comparator

PFI 5

Threshold

DAC

PLL

TCXO

Calibration

DAC

DDS

DDS Clock

TCXO

CLKIN

CLOCK and

TRIGGER

Routing

PCI Interface

PXI_CLK10_IN

PXI_CLK10

PXIPCI

PXI_STAR<0..16>

PXI_TRIG<0..7>

Figure 3-1. Functional Overview of the NI PXIe-6672

NI PXIe-6672 User Manual 3-2 ni.com

NI PXIe-6672 Front Panel

Figure 3-2 shows the connectors and LEDs on the front panel of the
NI PXIe-6672.

NI PXIe-6672

Timing Module

1 2

ACCESS ACTIVE

3

CLK
OUT

Chapter 3 Hardware Overview

1Access LED
2 Active LED
3 CLKOUT Connector

4

CLK

IN

PFI 0

PFI 1

PFI 2

5

PFI 3

PFI 4

PFI 5

4 CLKIN Connector
5 PFI <0..5> Connectors

Figure 3-2. NI PXIe-6672 Front Panel

© National Instruments Corporation 3-3 NI PXIe-6672 User Manual

Chapter 3 Hardware Overview

Access LED

Active LED

The Access LED indicates the communication status of the NI PXIe-6672.
Refer to Figure 3-2 for the location of the Access LED.

Table 3-1 summarizes what the Access LED colors represent.

Table 3-1. Access LED Color Indication

Color Status

Off Module is not yet functional.

Green Driver has initialized the module.

Amber Module is being accessed. The Access LED

flashes amber for 50 ms when the module is
accessed.

The Active LED can indicate an error or phase-locked loop (PLL) activity.
You can change the Active LED to amber, unless an error overrides the
selection. Refer to Figure 3-2 for the location of the Active LED.

Tip Changing the Active LED color to amber is helpful when you want to identify devices

in a multichassis situation or when you want an indication that your application has
reached a predetermined section of the code.

Table 3-2 illustrates the meaning of each Active LED color.

Table 3-2. Active LED Color Quick Reference Table

PXI_CLK10

Color

Red Ye s Ye s — —

Amber No No Ye s —

Green No No No Ye s

Off No No No No

Note A red Active LED can indicate that either PXI_CLK10 has stopped or that there is

a PLL error.

NI PXIe-6672 User Manual 3-4 ni.com

Stopped

PLL

Error

User

Setting

PLL

Active

Connectors

Chapter 3 Hardware Overview

This section describes the connectors on the front panel of the
NI PXIe-6672.

• CLKIN—Clock Input. This connector supplies the module with
a clock that can be programmatically routed to the onboard PLL
for use as a reference or routed directly to the PXI backplane
(PXI_CLK10_IN) for distribution to the other modules in the chassis.

• CLKOUT—Clock Output. This connector is used to source
a clock that can be routed programmatically from the
temperature-compensated crystal oscillator (TCXO), direct
digital synthesis (DDS), or backplane clock (PXI_CLK10).

• PFI <0..5>—Programmable Function Interface <0..5>. These
connectors can be used for either input or output. Additionally, PFI 0
can be used as a clock input for internally synchronizing other signals.
Refer to the Synchronous Routing section for more information about
this functionality. You can program the behavior of these PFI
connections individually.

Refer to Figure 3-2 for a diagram showing the locations of these
connections on the NI PXIe-6672 front panel.

Caution Connections that exceed any of the maximum ratings of input or output signals

on the NI PXIe-6672 can damage the module and the computer. NI is not liable for any
damage resulting from such signal connections.

Hardware Features

The NI PXIe-6672 perform two broad functions:

• Generating clock and trigger signals

• Routing internally or externally generated signals from one location
to another

© National Instruments Corporation 3-5 NI PXIe-6672 User Manual