NI-Sync User Manual - National Instruments
Contents
1. PXI PXI star R RTSI bus skew slave slot SMA NI Sync User Manual Phase locked loop The measure of the stability of an instrument and its capability to give the same measurement over and over again for the same input signal The amount of time required for a signal to pass through a circuit Precision Time Protocol the IEEE 1588 defined network protocol used to synchronize the clocks of multiple devices connected through a network A rugged open system for modular instrumentation based on CompactPCI with special mechanical electrical and software features The PXIbus standard was originally developed by National Instruments in 1997 and is now managed by the PXIbus Systems Alliance A special set of trigger lines in the PXI backplane for high accuracy device synchronization with minimal latencies on each PXI slot Real Time System Integration bus the NI timing bus that connects DAQ devices directly by means of connectors on top of the devices for precise synchronization of functions Seconds The actual time difference between two events that would ideally occur simultaneously Inter channel skew is an example of the time differences introduced by different characteristics of multiple channels Skew can occur between channels on one module or between channels on separate modules intermodule skew A computer or peripheral device controlled by another computer The place in the computer or cha2. This section assumes that you are using LabWindows CVI 7 0 or later to manage your code development and that you are familiar with the LabWindows CVI environment Developing an Nl Sync Application To develop an NI Sync application with LabWindows CVI complete the following steps 1 Open an existing or new project file 2 Load the NI Sync function panel at VxIpnp winnt niSync 3 Note The default installation directory has changed from C VXIPNP to C Program Files IVI Foundation VISA Upgrades over previous versions of NI VISA use the previous installation directory 3 Use the function panel to navigate the function hierarchy and generate function calls with the proper syntax and variable values Example Programs You can find LabWindows CVI example programs from the Windows Start menu at Start Programs National Instruments NI Sync Examples CVI Examples The examples are organized by measurement hardware NI Sync User Manual 2 2 ni com Chapter 2 Building and Programming Applications NI Sync Programming Flow Figure 2 1 shows the basic programming flow of typical signal based NI Sync applications NI Sync VIs and functions are organized under the Initialize Configure Hardware Connect Terminals Disconnect Terminals and Close categories to assist you in understanding where you should call a function or VI in your applications Functions and VIs that do not fall into the programming flow categories are consider
3. figure 2 4 NI PXIe 667x figure 2 3 reading a trigger time stamp 2 11 starting 1588 2 8 stopping 1588 2 12 utility VIs 2 14 instrument driver utility functions 2 14 programming language support 1 2 supported devices and platforms 1 2 niSync Clear Clock VI 2 12 niSync Clear Future Time Events VI 2 11 niSync Close VI 2 13 niSync Configure FPGA VI 2 15 niSync Connect Clock Terminals VI 2 6 niSync Connect Software Trigger VI 2 8 niSync Connect Trigger Terminals VI 2 7 niSync Create Clock VI 2 10 niSync Create Future Time Event VI 2 10 niSync Disable Time Stamp Trigger VI 2 11 niSync Disconnect Clock Terminals VI 2 12 niSync Disconnect Software Trigger VI 2 13 niSync Disconnect Trigger Terminals VI 2 13 niSync Enable Time Stamp Trigger VI 2 10 niSync Error Message VI 2 14 niSync Get Time VI 2 9 niSync Initialize VI 2 5 niSync Measure Frequency VI 2 15 niSync Read Trigger Time Stamp VI 2 11 niSync Reset VI 2 14 niSync Revision Query VI 2 14 National Instruments Corporation 1 3 Index niSync Self Test VI 2 14 niSync Send Software Trigger VI 2 8 niSync Start 1588 VI 2 9 niSync Stop 1588 VI 2 12 niSync_ClearClock function 2 12 niSync_ClearFutureTimeEvents function 2 11 niSync_close function 2 13 niSync_ConfigureFPGA function 2 15 niSync_ConnectClkTerminals function 2 6 niSync_ConnectS WTrigToTerminal function 2 8 niSync_ConnectTrigTerminals function 2 7 niSync_CreateClock function 2 10
4. C Y Microsoft Visual C 5 0 or later Installing the Software The software package that ships with the NI PXI 665x NI PXI 6672 NI PXI 6674T NI PXI 6682H and NI PCI 1588 provides the following items e NI Sync driver software e LabVIEW example code e LabWindows CVI example code Complete the following steps to install your NI Sync software 1 Log in to the development computer as an administrator or as a user with administrative privileges 2 Insert the NI Sync installation media NI Sync User Manual 1 2 ni com Chapter 1 Introduction Installation and Configuration 3 Run the Setup exe program to install the NI Sync software on your system Several examples are included to give you a starting point in using the NI timing and synchronization modules Additional examples for using NI timing modules with other devices are online at ni com examples 3 Note Be sure to install the NI Sync software before installing your device hardware Device and System Configuration Before you begin using your NI timing devices you must ensure that your PXI system software is configured properly NI Sync uses PXI configuration information to enable features such as chassis identification slot identification and trigger terminal reservation This configuration information is enabled by identifying your PXI system components in Measurement amp Automation Explorer MAX Refer to your PXI hardware
5. The length of a 1588 epoch is 2 seconds The 1588 clock to which all other 1588 devices in a specific PTP subdomain are synchronized The 1588 clock to which other 1588 devices are synchronized if they are directly connected to it that is they are not connected through a boundary clock The time format specified by IEEE 1588 IEEE 1588 represents time as a 32 bit unsigned integer for the number of seconds and a 32 bit unsigned integer for the number of nanoseconds since the 1588 epoch From 1 January 1972 onward 1588 time follows TAI time with an offset of 10 seconds Percent Plus or minus Positive of or plus National Instruments Corporation G 1 NI Sync User Manual Glossary A accumulator ADE asynchronous backplane backplane synchronization clock bus Clk In CIk Out NI Sync User Manual Negative of or minus Per Degree Ohm A part where numbers are totaled or stored Application development environment A property of an event that occurs at an arbitrary time without synchronization to a reference clock An assembly typically a printed circuit board PCB with 96 pin connectors and signal paths that bus the connector pins PXI systems have two connectors called the J1 and J2 connectors The clock signal that is used to synchronize the RTSI PXI triggers or PXI_Star triggers on an NI PXI 665x The group of conductors that interconnect individual circuitry in a computer Typi
6. in MAX 3 Note The DAQmx device name VISA Resource Name and VISA alias are all valid inputs for the Resource Name to create a session to a device using the NI Sync API Refer to Chapter 2 Building and Programming Applications for detailed information about device initialization 5d 7 NIP PXI2Slot7 Measurement amp Automation Explorer o JO a File Edit View Tools Help a Y My System X Delete Ep Self Test Y Test Panels R Reset Device Self Calibrate E Data Neighborhood 7 4 ry Devices and Interfaces Name Value Beck o E ai 4 ap NI PXIle 1062 Chassis 2 Serial Number OxE543BB a 7 NI PXI 6652 PXIZSlot7 XI Slot Number 7 NI DAQm Device a Network Devices PA Chassis Number 2 Basics a PX PXI System NI PXle 8102 What do you want to do ud Chassis 2 NI PXIe 1062 Run the NI DAQmx Y Serial amp Parallel Test Panels sA Scales Remove the device fey Software M Drivers gt iew or change device properties amp Remote Systems Attributes B Device R PSP VISA Prop 8 PX Setti Calibrati Figure 1 1 NI PXI 665x Device Information in MAX NI Sync User Manual 1 4 ni com Building and Programming Applications This chapter describes the fundamentals of building and programming NI Sync applications for LabVIEW and LabWindows CVI The NI Sync Instrument Driver The NI Sync driver software includes an instrument driver API for c
7. niSync_CreateFutureTimeEvent function 2 10 niSync_DisableTimeStampTrigger function 2 11 niSync_DisconnectClkTerminals function 2 12 niSync_DisconnectSWTrigFromTerminal function 2 13 niSync_DisconnectTrigTerminals function 2 13 niSync_EnableTimeStampTrigger function 2 10 niSync_error_message function 2 14 niSync_GetTime function 2 9 niSync_init Function 2 5 niSync_MeasureFrequency function 2 15 niSync_ReadMultipleTriggerTimeStamp function 2 11 niSync_ReadTriggerTimeStamp function 2 11 niSync_reset function 2 14 niSync_revision_query function 2 14 niSync_self_test function 2 14 niSync_SendSoftwareTrigger function 2 8 niSync_Start1588 function 2 9 niSync_Stop1588 function 2 12 NI Sync User Manual Index P performing measurements 2 10 PPS 3 5 synchronizing to 3 5 programming applications 2 1 programming examples NI resources A 1 programming flow 2 3 NI PCI 1588 figure 2 4 NI PXI 665x figure 2 3 NI PXI 6682H figure 2 4 NI PXIe 667x figure 2 3 programming language support 1 2 pulse per second PPS 3 5 R reading a trigger time stamp 2 11 related documentation viii S software installation 1 2 NI resources A 1 trigger terminals connecting 2 8 disconnecting 2 13 starting 1588 2 8 stopping 1588 2 12 support technical A 1 supported devices and platforms 1 2 synchronizing to a pulse per second 3 5 synchronizing to GPS time 3 3 system configuration 1 3 NI
8. the frequency of a signal The following VI and function support this operation LabVIEW VI C Function niSync Measure Frequency niSync_MeasureFrequency Frequency measurement is useful for verifying that clock signals are properly connected For example a clock signal connected to PXI_Star3 could be measured by connecting the PXI_Star3 terminal to the measurement terminal and calling the Measure Frequency VI or function FPGA Reconfiguration UN Caution FPGA Reconfiguration is a sensitive operation that can damage your module Do not use this operation unless you are confident about what you are doing Your hardware may support an on demand update of the field programmable gate array FPGA with a new bitstream The following VI and function support this operation LabVIEW VI C Function niSync Configure FPGA niSync_ConfigureFPGA National Instruments Corporation 2 15 NI Sync User Manual Timing Protocols Distributed Time Technology Overview Measurement and automation systems involving multiple devices often require accurate timing for event synchronization and data correlation For example an industrial automation application may need to synchronize distributed motion controllers or a test and measurement application may need to correlate data acquired from sensors distributed across a device under test You can achieve this synchronization through signal based or time based sy
9. 008 provides fault tolerant synchronization among heterogeneous networked clocks requiring little network bandwidth overhead processing power and administrative setup IEEE 1588 provides this by defining a protocol known as the precision time protocol PTP GPS Global Positioning System GPS is a system of satellites funded and controlled by the US Department of Defense While GPS is typically considered a technology used to determine location GPS is also an extremely accurate time source Every GPS satellite contains multiple atomic clocks The atomic clocks are controlled and referenced to the Master Clock MC at the United States Naval Observatory USNO called UTC USNO The RMS difference between each individual satellite and UTC USNO is generally between 2 and 20 ns GPS receivers use signals from multiple satellites and use averaging algorithms to determine time so individual satellite drift is not as significant as the average drift of the entire satellite constellation The RMS difference of the averaged constellation and UTC USNO is routinely maintained to be no greater than 10 ns Therefore you can expect the error the satellite distribution medium introduces into the GPS receiver to be within 10 ns of UTC USNO globally Synchronizing to GPS Time The NI PXI 6682 can use GPS technology as a Time Reference The device uses the time updates received by the onboard GPS receiver every second derives from it the curre
10. G 2 0 R3 0 CompactPCI Core Specification available from PICMG available from www picmg org PXI Specification Revision 2 1 available from www pxisa org NI PXI 665x User Manual available from ni com manuals Getting Started with Multi Chassis Synchronization Using the NI PXI 665x available from ni com manuals NI PCI 1588 User Manual available from ni com manual s NI PXI 6682 User Manual NI PXle 6672 User Manual NI PXle 6674T User Manual KnowledgeBase article 4C6CKR8P available from ni com support viii ni com Introduction Installation and Configuration This chapter provides an overview of the NI Sync driver software and explains how to install and configure NI Sync for use with National Instruments timing modules About the NI Sync Driver Software Introduction NISync is a library of VIs and functions for controlling NI timing modules You can use NI Sync to configure the timing and synchronization of your system This can include signal based synchronization such as sharing triggers and clocks to be used directly You can also do time based synchronization using time protocols such as IEEE 1588 IRIG or GPS as a time reference to time stamp or perform synchronized generation of clocks and triggers Use NI Sync in conjunction with other measurement software such as NI DAQm x for advanced timing high channel count distributed or multiple instrument applications The NI Sync driver software include
11. Hz sine wave The reception of the first bit of an IRIG B frame causes a time stamp to be generated for the event The time stamp cannot be read or used as a Time Reference until the entire IRIG B frame has been received and decoded After a successful decode of the frame it drives the Time Reference engine if IRIG B is configured as the Time Reference Both the time stamp generated by receiving the first frame bit and the time date encoded in the IRIG B frame can be read using the Read Last IRIG Time Stamp function PPS Synchronizing to a Pulse Per Second PPS The NI Sync timing family of devices can use an external pulse per second PPS signal as a Time Reference Configuring PPS as the Time Reference configures the device to interpret a rising edge on the configured input as representing a second s boundary As the PPS signal cannot indicate an absolute time you can configure the device to use either a manual start time or its current time and use the PPS signal only to correct frequency If configured to use a manual start time the first pulse received on the configured PPS input terminal is interpreted to represent the start time configured Every subsequent pulse is interpreted as having occurred one second after the previous pulse This configuration allows for easy synchronization of multiple systems instrumented with niSync timing family devices if absolute time is not a concern You can configure the systems to be synchro
12. PLICATION INCLUDING THE ABOVE RELIABILITY OF OPERATION OF THE SOFTWARE PRODUCTS CAN BE IMPAIRED BY ADVERSE FACTORS INCLUDING BUT NOT LIMITED TO FLUCTUATIONS IN ELECTRICAL POWER SUPPLY COMPUTER HARDWARE MALFUNCTIONS COMPUTER OPERATING SYSTEM SOFTWARE FITNESS FITNESS OF COMPILERS AND DEVELOPMENT SOFTWARE USED TO DEVELOP AN APPLICATION INSTALLATION ERRORS SOFTWARE AND HARDWARE COMPATIBILITY PROBLEMS MALFUNCTIONS OR FAILURES OF ELECTRONIC MONITORING OR CONTROL DEVICES TRANSIENT FAILURES OF ELECTRONIC SYSTEMS HARDWARE AND OR SOFTWARE UNANTICIPATED USES OR MISUSES OR ERRORS ON THE PART OF THE USER OR APPLICATIONS DESIGNER ADVERSE FACTORS SUCH AS THESE ARE HEREAFTER COLLECTIVELY TERMED SYSTEM FAILURES ANY APPLICATION WHERE A SYSTEM FAILURE WOULD CREATE A RISK OF HARM TO PROPERTY OR PERSONS INCLUDING THE RISK OF BODILY INJURY AND DEATH SHOULD NOT BE RELIANT SOLELY UPON ONE FORM OF ELECTRONIC SYSTEM DUE TO THE RISK OF SYSTEM FAILURE TO AVOID DAMAGE INJURY OR DEATH THE USER OR APPLICATION DESIGNER MUST TAKE REASONABLY PRUDENT STEPS TO PROTECT AGAINST SYSTEM FAILURES INCLUDING BUT NOT LIMITED TO BACK UP OR SHUT DOWN MECHANISMS BECAUSE EACH END USER SYSTEM IS CUSTOMIZED AND DIFFERS FROM NATIONAL INSTRUMENTS TESTING PLATFORMS AND BECAUSE A USER OR APPLICATION DESIGNER MAY USE NATIONAL INSTRUMENTS PRODUCTS IN COMBINATION WITH OTHER PRODUCTS IN A MANNER NOT EVALUATED OR CONTEMPLATED BY NATIONAL INSTRUMENTS THE USER OR APPLICATION DESIGNER IS UL
13. PXI NI Sync User Manual August 2011 7 NATIONAL 370926F 01 INSTRUMENTS Worldwide Technical Support and Product Information ni com Worldwide Offices Visitni com niglobal to access the branch office Web sites which provide up to date contact information support phone numbers email addresses and current events National Instruments Corporate Headquarters 11500 North Mopac Expressway Austin Texas 78759 3504 USA Tel 512 683 0100 For further support information refer to the Technical Support and Professional Services appendix To comment on National Instruments documentation refer to the National Instruments Web site at ni com info and enter the Info Code feedback O 2003 2011 National Instruments Corporation All rights reserved Important Information Warranty 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 mar
14. Sync User Manual 1 4 T technical support A 1 time reference 3 2 timing protocols 3 1 1588 3 3 distributed time technology overview 3 1 GPS 3 3 IRIG 3 5 PPS 3 5 time reference 3 2 timing technologies application of 3 6 timing technologies application of 3 6 training and certification NI resources A 1 trigger terminals connecting 2 7 disconnecting 2 13 troubleshooting NI resources A 1 U utility VIs 2 14 instrument driver utility functions 2 14 W Web resources A 1 Windows application creating using LabVIEW 2 1 using LabWindows CVI 2 2 ni com
15. TIMATELY RESPONSIBLE FOR VERIFYING AND VALIDATING THE SUITABILITY OF NATIONAL INSTRUMENTS PRODUCTS WHENEVER NATIONAL INSTRUMENTS PRODUCTS ARE INCORPORATED IN A SYSTEM OR APPLICATION INCLUDING WITHOUT LIMITATION THE APPROPRIATE DESIGN PROCESS AND SAFETY LEVEL OF SUCH SYSTEM OR APPLICATION Contents About This Manual CRA O vii Related DocuMentatiOM ccccccccccncnnnnnnnnnnananannnnnnonnnnnonononononononononnnnananon ono nnnnnnncncnonononinons viii Chapter 1 Introduction Installation and Configuration About the NI Sync Driver Software ooooocnocncoccoonconcononnncnnonnncnn cnn nonn cnn ncnn conc cnn non cnn conca 1 1 Intro CUCU OM is perito Nota vedas ti sigtates p a ag dosteasea geste 1 1 Supported Devices and Platforms oooonnoncnicnnonnnonconnnancnncnnncnncnnn corona non ncnncnn nono 1 2 Application Software and Programming Language Suppott 0 ee 1 2 Installing the SoftWare senno iiaiai eii ii ia ii 1 2 Device and System Configuration cece eseeecceseeseeeeceeeeseeseeeaeceeeeseceesaesseseaeesees 1 3 Using Measurement amp Automation Explorer eee eeeeseeeeseeeeeeeenees 1 3 Locating Your NI Timing and Synchronization Devices 1 3 Chapter 2 Building and Programming Applications The Ni Syne Instrument Drivers iii o 2 1 Creating a Windows Application Using LabVIEW ooooococcnicnccnccncononancnnonnonncnnncnncnnno 2 1 Developing an NI Sync Application oooocnoconocnocnoonconcnononanonacanonono
16. ach of these sources provides periodic time updates GPS satellites for example broadcast the current time once per second on the second s boundary When used as a Time Reference on the niSync timing family of devices the niSync timing device uses this once per second update as a reference time The niSync timing device uses a sequence of these reference times to match the source of the reference times in frequency and phase as closely as possible The niSync timing device has an onboard clock used to provide clock holdover between reception of reference times and the previously received reference times are used to adjust the onboard clock frequency and phase The end result is that the niSync timing device can provide a continuous time source synchronized to the device s Time Reference as closely as possible and makes it possible to tightly synchronize multiple distributed clocks using a single Time Reference technology Regardless of the Time Reference in use the niSync timing family of devices adjusts its board time to the TAI timescale Therefore regardless of Time Reference all events and time stamps occur in the TAI timescale Refer to KnowledgeBase 4C6CKR8P for more information about timescales NI Sync User Manual 3 2 ni com Chapter 3 Timing Protocols 1588 IEEE 1588 2008 Protocol IEEE 1588 provides a standard protocol for synchronizing clocks connected through a multicast capable network such as Ethernet TEEE 1588 2
17. cally a bus is the expansion vehicle to which I O or other devices are connected An example of a PC bus is the PCI bus Celsius Clk In is a signal connected to the SMA or SMB input pin of the same name Clk In can serve as PXI_CIk10_IN or be used as a phase lock reference for the OCXO Clk Out is the signal on the SMA or SMB output pin of the same name The OCXO clock DDS clock or PXI_CIK10 may be routed to Clk Out G 2 ni com clock CompactPCI D D A DAC DAQ DC DDS E EEPROM ESD F frequency frequency tuning word front panel O National Instruments Corporation G 3 Glossary Hardware component that controls timing for reading from or writing to groups A Eurocard configuration of the PCI bus for industrial applications Digital to analog Digital to analog converter an electronic device that converts a digital number into a corresponding analog voltage or current Data acquisition 1 collecting and measuring electrical signals from sensors transducers and test probes or fixtures and inputting them to a computer for processing 2 collecting and measuring the same kinds of electrical signals with A D and or DIO devices plugged into a computer and possibly generating control signals with D A and or DIO devices in the same computer Direct current Direct Digital Synthesis a method of creating a clock with a programmable frequency Electrically erasable programmable read
18. chnical support options in your area visit ni com services or contact your local office at ni com contact Training and Certification Visit ni com training for training and certification program information You can also 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 National Instruments Alliance Partner members can help To learn more call your local NI office or visit ni com alliance Calibration Certificate If your product supports calibration you can obtain the calibration certificate for your product at ni com calibration A 1 NI Sync User Manual Appendix A Technical Support and Professional Services You also can visit the Worldwide Offices section of ni com niglobal to access the branch office Web sites which provide up to date contact information support phone numbers email addresses and current events NI Sync User Manual A 2 ni com Glossary Symbol Prefix Value p pico 10 22 n nano 1072 u micro 10 6 m milli 10 3 k kilo 103 M mega 106 G giga 10 T tera 10 Numbers Symbols 1588 epoch A period of absolute time defined by the IEEE 1588 specification The 1588 grandmaster clock 1588 master clock 1588 time I current 1588 epoch is assigned the number 0 and started at 0 hours 1 January 1970
19. connnnncnncrnncnn cinc canonnnons 2 13 Clos iii dat i 2 13 O 2 14 Instrument Driver Utility Functions oooncnncnnoninnnnoncnncnonconcnnncannnanono 2 14 AVANCE vcd dr ie ii 2 15 Frequency Measurement eeeecseseeseeseeeeeeseceeeeseseeeeseeseeeaeeseees 2 15 FPGA Reconfiguration cococcocnnonconconnconcnnnonnnnnnonnonncrn conan rn ncnnnrnncncnnnons 2 15 Chapter 3 Timing Protocols Distributed Time Technology OVervieW oocooccnocnnonconconcnonconnnnncononnonnnonncnn conca no nrnncnnccnnos 3 1 Tune Refereite seenen en a a E EO itica da 3 2 LIO A A RT 3 3 IEFE1588 2008 ProtocoL detroit ori enterada ii 3 3 C eeo AEE A a ee 3 3 Synchronizing to GPS TIME nprs ni i AE Ee sees sesiones 3 3 Factors Affecting GPS Synchronization ACCULACY coocoocccocnoononnnonccnnonaninncnnccnnos 3 4 IRIG sess RARO 3 5 IRIG Standard 200 04 n iiie aaee a e a e ES TE Aa iS 3 5 PPS mon A A A E A R iets 3 5 Synchronizing to a Pulse Per Second PPS ooooococinccccoconocononcconnnconnconncnnnccnncoo 3 5 Application of Timing Technologies ececsesscsessseessessessessesscssessessenesseeseesegs 3 6 Appendix A Technical Support and Professional Services Glossary Index NI Sync User Manual vi ni com About This Manual Conventions The N Sync User Manual is for users of the NI Sync driver software an application programming interface API for controlling National Instruments timing modules This manual describes the fundamentals of developing applica
20. e GPS antenna should be mounted in a location where it has an unobstructed clear view of the entire sky This means that from the location of the GPS antenna every horizon is visible This orientation allows the GPS receiver to detect additional satellites and perform additional averaging while discarding the worst signals It also helps to alleviate effects of multipath where the GPS receiver does not receive the direct signal from the satellite and instead receives a signal reflected off an object or surface Multipath signals are delayed in reception and therefore degrade the average timing performance Additionally it is best to ensure the antenna is in a fixed location through the self survey process and throughout use The self survey improves accuracy by performing long term averaging of location during the self survey Any small movement of the antenna during this process or during use reduces accuracy Even a fixed position antenna may be subject to movement caused by wind or vibration and should be minimized Antenna cable latency also adds constant error For most accurate results you must calculate the latency of the GPS antenna cable in use and apply a correction The niSync timing family of devices supports the Clock Adjustment Offset property to allow this source of error to be removed For example if the antenna cable in use has a published latency of 5 ns m and the antenna installation uses 30 m of cable the total delay that t
21. e a session is open Terminals must be explicitly disconnected using Disconnect VIs functions or by resetting the module However for an NI PCI 1588 or PXI 6682 session calling Close stops clears and disables operations configured within the session That is if you started PTP within the session calling Close stops PTP Likewise if you created a future time event within the session it is cleared if you enabled a time stamp trigger it is disabled if you created a clock it is cleared Utility In addition to resource and terminal connection management NI Sync includes several Utility VIs and functions for performing tasks such as resetting the device converting error codes to messages and obtaining information about existing terminal connections Instrument Driver Utility Functions In addition to terminal connection information NI Sync supports the standard set of instrument driver utility functions LabVIEW VIs C Function niSync Reset niSync_reset niSync Self Test niSync_self_test niSync Revision Query niSync_revision_query niSync Error Message niSync_error_message Refer to the NI Sync API Reference for details regarding these functions NI Sync User Manual 2 14 ni com Chapter 2 Building and Programming Applications Advanced NI Sync also includes advanced features including frequency measurement and FPGA reconfiguration Frequency Measurement Some hardware may be able to measure
22. ead Trigger Timestamp Clear Future Disable Timestamp Clear Time Events Trigger Clock Close Resources Figure 2 2 Basic Programming Flow of an NI Sync Application with NI PCI 1588 and NI PXI 6682H Devices ays Note Using MAX you can configure the 1588 PTP protocol to start automatically at boot NI Sync User Manual 2 4 ni com Chapter 2 Building and Programming Applications Initialize For any application you write you must first open a session to establish communication with the NI timing and synchronization device using the Initialize VI or function LabVIEW VI C Function niSync Initialize niSync_init In addition to establishing a session with the timing module niSync Initialize can reset the device to a known state and verify that the NI Sync instrument driver is valid for a particular instrument The Initialize VI or function returns a ViSession handle you can use to identify the instrument in all subsequent NI Sync calls 3 Note The Initialize VI and function take the DAQmx Device Name or VISA Resource Name corresponding to an NI timing device and use this information to locate the instrument and create a session to it You can obtain the DAQmx Device Name and VISA Resource Name for an instance of your device using MAX Refer to Chapter 1 Introduction Installation and Configuration for an example of using MAX The Initialize VI and function create a new instrument session Any
23. ed Advanced or Utility functions that perform various tasks such as resetting timing devices and other functions Initialize Y Configure Hardware y Connect Terminals y Utility Configure and Perform Measurement Advanced Disconnect Terminals Close Figure 2 1 Basic Programming Flow of an NI Sync Application with NI PXI 665x and NI PXle 667x Devices National Instruments Corporation 2 3 NI Sync User Manual Chapter 2 Building and Programming Applications Figure 2 2 shows the basic programming flow of typical time based NISync applications NI Sync VIs and functions are organized under the Initialize Configure Hardware Get Time Create Future Time Event Enable Time Stamp Trigger Create Clock Read Trigger Time Stamp Clear Future Time Events Disable Time Stamp Trigger Clear Clock and Close categories to assist you in understanding where you should call a function or VI in your applications Functions and VIs that do not fall into the programming flow categories are considered Advanced or Utility functions These functions perform various tasks such as resetting devices returning the revision number of the NI Sync instrument driver and instrument firmware and other functions Initialize y Configure Hardware y Get Time y Y Y Create Future Enable Timestamp Create Time Event Trigger Clock R
24. he antenna installation causes is 150 ns You can correct this by setting the Clock Adjustment Offset to 150 Remember to account for all sources of delay in your GPS installation including cable lightning arrestors or amplifiers The niSync timing family of devices supports querying the number of visible satellites through the Satellites Available property and determining if any fatal GPS errors are present through the Status property A minimum of four satellites should be visible for stable GPS clock operations and GPS clock accuracy and stability increase as the number of visible satellites increases Fatal GPS errors such as less than four satellites visible are reported through the Status property 3 4 ni com Chapter 3 Timing Protocols IRIG IRIG Standard 200 04 The Inter Range Instrumentation Group IRIG currently defines six serial protocols for distributing time codes Each of the six versions described in the IRIG specification describes a data frame format containing time date information and the means for signaling and encoding the data IRIG B is probably the most common IRIG format and is the one the NI PXI 6682 supports IRIG B specifies that a 100 bit time frame is transmitted once per second with each bit having a duration of 10 ms Data in the time frame includes Binary Coded Decimal BCD time of year year and straight binary seconds SBS The data can be DC biased DC or amplitude modulated AM with a 1 k
25. his allows the terminal generating the clock to be used for other operations The following VI and function deal with clearing clocks LabVIEW VI C Function niSync Clear Clock niSync_ClearClock Stop 1588 After you no longer want to synchronize the 1588 clock on the NI PCI 1588 or NI PXI 6682H PTP can be stopped However PTP should not be stopped if other operations are currently configured The following VI and function deal with stopping PTP LabVIEW VI C Function niSync Stop 1588 niSync_Stop1588 Disconnect Terminals After a measurement has been performed connected terminals should be disconnected This returns the PXI system to its pre measurement state and frees any reserved resources for use Terminals are disconnected by supplying the connected source and destination terminals to Disconnect VIs or functions Terminals are disconnected according to their type used for generating the connection Clock Terminals Use the following VI or function to disconnect clock terminals LabVIEW VI C Function niSync Disconnect Clock niSync_DisconnectClkTerminals Terminals NI Sync User Manual 2 12 ni com Chapter 2 Building and Programming Applications Trigger Terminals Use the following VI or function to disconnect trigger terminals LabVIEW VI C Function niSync Disconnect niSync_DisconnectTrigTerminals Trigger Terminals Softwa
26. ising or falling edge of the specified synchronization clock or delayed by an integer multiple of the synchronization clock period ay Note The NI PXI 6682 H and NI PCI 1588 can implement similar functionality by creating a Future Time Event Start 1588 NI Sync User Manual The following VIs and functions deal with software trigger terminal connections LabVIEW VIs C Functions niSync Connect niSync_ConnectSwTrigToTerminal Software Trigger niSync Send niSync_SendSoftwareTrigger Software Trigger After you have configured the NI PCI 1588 or NI PXI 6682 device you can start the Precision Time Protocol PTP PTP synchronizes the clock on the NI device according to the IEEE 1588 specification For more information regarding PTP and the IEEE 1588 specification refer to Chapter 3 Timing Protocols In general you should start 1588 and ensure it has been synchronized before performing any other operations with the NI device 2 8 ni com Chapter 2 Building and Programming Applications Note Using MAX you can configure the 1588 PTP protocol to start automatically at boot This is enabled by default GQ g Note When an NI device is participating in PTP as a slave device it may be required to perform a macro phase adjustment A macro phase adjustment is when the 1588 clock is adjusted by a significant amount and therefore the 1588 time no longer atomically increments This should not occur on a well desig
27. ked 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 EXCEPT AS SPECIFIED HEREIN NATIONAL INSTRUMENTS MAKES NO WARRANTIES EXPRESS OR IMPLIED AND SPECIFICALLY DISCLAIMS ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE CUSTOMER S RIGHT TO RECOVER DAMAGES CAUSED BY FAULT OR NEGLIGENCE ON THE PART OF NATIONAL 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 POSSIBILITY THEREOF This limitation of the liability of National Instruments will apply regardless of the form of action whether in contract or tort including negligence Any action agains
28. mp After you have enabled a time stamp trigger you can read all generated time stamps The time stamp is the 1588 clock time on the NIPCI 1588 and NI PXI 6682H device when the specified terminal changes its state The following VI and function deal with reading trigger time stamps LabVIEW VI C Function niSync Read niSync_ReadTriggerTimeStamp Trigger Time niSync_ReadMultipleTriggerTimeStamp Stamp Clear Future Time Events After you no longer want to generate future time events they should be cleared This allows the terminal generating time stamps to be used for other operations Clearing future time events on a specific terminal clears all future time events for that terminal The following VI and function deal with clearing future time events LabVIEW VI C Function niSync Clear Future niSync_ClearFutureTimeEvents Time Events Disable Time Stamp Trigger After you no longer want to generate time stamps they should be disabled This allows the terminal generating time stamps to be used for other operations The following VI and function deal with disabling time stamp triggers LabVIEW VI C Function niSync Disable niSync_DisableTimeStampTrigger Time Stamp Trigger National Instruments Corporation 2 11 NI Sync User Manual Chapter 2 Building and Programming Applications Clear Clock After you no longer want to generate a clock it should be cleared T
29. n 2 9 NI Sync User Manual Chapter 2 Building and Programming Applications The following VI and function deal with creating future time events LabVIEW VI C Function niSync Create Future niSync_CreateFutureTimeEvent Time Event Enable Time Stamp Trigger You can generate a time stamp when a signal at any NI terminal changes its level by enabling a time stamp trigger The time stamp is the board time on the NI time based device when the specified terminal changed state The following VI and function deal with enabling time stamp triggers LabVIEW VI C Function niSync Enable niSync_EnableTimeStampTrigger Time Stamp Trigger Create Clock You can generate a clock at destination terminals You can start and stop the clock at a specific board time The clock is synchronized to the board clock The following VI and function deal with creating clocks LabVIEW VI C Function niSync Create Clock nisync_CreateClock Configure and Perform Measurement After making terminal connections you are ready to perform your measurement Taking a measurement is an application specific operation that typically involves the use of a Measurements API such as NI DAQmx NI Scope NI FGEN or others For example code to get started with measurement synchronization refer to ni com examples NI Sync User Manual 2 10 ni com Chapter 2 Building and Programming Applications Read Trigger Time Sta
30. nchronization Signal based synchronization involves sharing signals such as clocks and triggers directly between nodes that need to be synchronized Time based synchronization involves nodes independently synchronizing their time to a time reference There are advantages and disadvantages to both methods of device synchronization In systems where the devices are near each other sharing a common timing signal is generally the easiest and most accurate method of synchronization For example modular instruments in a PXI chassis all share a common 10 MHz clock signal from the PXI backplane enabling synchronization to less than 1 ns To accurately use a common timing signal a device must be calibrated to account for the signal propagation delay from the timing source to the device Sharing a common timing signal becomes unfeasible when the distance between devices increases or when devices frequently change location Even at moderate distances a common timing signal may require significant costs for cabling and configuration In these situations time based synchronization may be necessary Using this approach devices act on timing signals originating from a local clock that is synchronized to the other clocks in the system Examples of distributed clock synchronization include devices synchronized to GPS satellites a PC s internal clock synchronized to an NTP time server a group of devices participating in the IEEE 1588 protocol or devices sy
31. nchronized to a common IRIG B source Instead of sharing timing signals directly these devices periodically exchange information and adjust their local timing sources to match each other O National Instruments Corporation 3 1 NI Sync User Manual Chapter 3 Timing Protocols The synchronization of distributed time requires a continuous process A clock is essentially a two part device consisting of a frequency source and an accumulator In theory if two clocks were set identically and their frequency sources ran at the exact same rate they would remain synchronized indefinitely In practice however clocks are set with limited precision frequency sources run at slightly different rates and the rate of a frequency source changes over time and temperature Most modern electronic clocks use a crystal oscillator as a frequency source The frequency of a crystal oscillator varies due to initial manufacturing tolerance temperature and pressure changes and aging Because of these inherent instabilities distributed clocks must be synchronized continually to match each other in frequency and phase Time Reference The niSync timing family of devices including the NI PCI 1588 and NI PXI 6682 use Time Referencing to synchronize frequency and phase with a Time Reference A Time Reference is an external time source that provides periodic time updates Some examples of Time References are GPS satellites IEEE 1588 masters or IRIG B sources E
32. ned and stable network If this occurs future time events clocks and time stamps may be affected If the 1588 time is set forward future time events and clock transitions that were missed occur immediately If the 1588 time is set backward future time events and clock transitions are delayed 3 Note Ifthe 1588 clock participating in the PTP enters the faulty state future time events clocks and time stamps will no longer be synchronized with other 1588 devices participating in the PTP This should not occur on a well designed and stable network You can check for this condition by monitoring the 1588 clock state property The following VI and function deal with starting PTP LabVIEW VI C Function niSync Start 1588 niSync_Start1588 Get Time This function queries a time based synchronization board for the current board time The following VI and function deal with getting the 1588 time LabVIEW VI C Function niSync Get Time niSync_GetTime Create Future Time Event You can change a signal level of a device terminal at a specific time by creating a future time event When the time on the time based device reaches the specified time the signal level is changed as the future time event specifies You can create multiple future time events that change the signal levels on different terminals or change the signal at the same terminal to create waveforms National Instruments Corporatio
33. nized to use PPS as the Time Reference with the same manual start time configured You then can connect the PPS signal to the systems and start the PPS output As the systems are connected to the same signal they are closely synchronized National Instruments Corporation 3 5 NI Sync User Manual Chapter 3 Timing Protocols If configured not to use a manual start time the first pulse received is interpreted to represent the time equal to the device s current time Therefore no correction is applied when the first pulse is received Every subsequent pulse is interpreted as having occurred one second after the previous pulse This configuration allows for distributing frequency corrections to multiple systems without concern for actual time values For best results when using PPS Time Reference ensure that the device supplying the PPS signal can provide a stable consistent 1 Hz signal You can achieve optimal results when an Oven Controlled Crystal Oscillator OCXO or better drives the source signal You can introduce error into the system if the reference signal contains significant jitter or the reference frequency strays from 1 Hz Application of Timing Technologies Because distributed clocks using Time Referencing have precise synchronization capabilities they are being used for many applications including Test and measurement e Factory automation e Power plants Telecommunications Robotic control You can u
34. nncnnncnncrnncnnons 2 1 Example Programs ici ets ell ats en Re eae ee 2 2 Creating a Windows Application Using LabWindows CVL oooonconncnocnnoccononancononancanonnnos 2 2 Developing an NI Sync Application oononicnnocnononancnnnnancnnonncnn cnn nnnncnnncnnconccnnos 2 2 Example PTOS erat daria aE A e N eaten dae ANAE 2 2 NI Sync Programming FloW irn n E RE E non ncnn nro nonn nro E 2 3 Initializes oi id a De 2 5 Configure Hard Wade vinotinto na ies 2 5 Accessing ATITIbDULES aiii liinda 2 5 Connect TermimalSivaiia A A ek A 2 6 Clock Terminal Sierens a E ERA ER ETERA 2 6 Trigger Terminal na a e A AAE AAAS EEES 2 7 Software Trigger Terminals oooncnnonnnnonnnonconnnoncnnnonncanornncnncnnncano nacen 2 8 Sat tas 2 8 A NANO 2 9 Create Future Time Eventos menaa eh ga aids da 2 9 Enable Time Stamp Trio get sesers roiete etia dir i a nen 2 10 Create Clock a 2 10 Configure and Perform Measurement coooococcnonconnnonconcnnnonnnoncnnnonnncnnonnncnnonnnonnons 2 10 National Instruments Corporation v NI Sync User Manual Contents Read Trigger Time Stamp cenicero ia e a E 2 11 Clear Future Time Events ii sccsctesdeni3tsteatesssiaves diiniita 2 11 Disable Time Stamp Trigger ceseescsssssececesesesersecescerevessestesoseseccoeerees 2 11 Clear Clocks ta tia 2 12 Sp lui alista 2 12 Disconnect Terminals iia aiii anita 2 12 Clock Terminales vientos nuit 2 12 Trigger Terminal Susini dci 2 13 Software Trigger TerminalS ooonconnnnnnnnnnocnonnnon
35. nt TAI time and applies this time as the current board time When you initially connect the GPS antenna to the NI PXI 6682 the onboard GPS receiver searches for visible satellites After detecting at least four satellites the GPS receiver performs a self survey During a self survey GPS can be used as a Time Reference but is less accurate than after the self survey has completed The self survey is a process of performing measurements of the visible satellites once per second and averaging those measurements so that the current position can be determined as accurately as possible Once the accurate position is determined time data received from the GPS satellites can be precisely applied National Instruments Corporation 3 3 NI Sync User Manual Chapter 3 Timing Protocols A self survey is applied only if the NI PXI 6682 is not configured for mobile mode Use mobile mode if the antenna is moving while the device has power If the antenna is moving and mobile mode is not enabled you may get unexpected and invalid timing results However using mobile mode degrades onboard GPS receiver accuracy and you should not use it unless the antenna is moving For most accurate results disable mobile mode and maintain the antenna in a fixed position Factors Affecting GPS Synchronization Accuracy NI Sync User Manual You can obtain the best GPS timing results by having an ideally located long term stable GPS antenna installation Ideally th
36. onfiguring attributes and programming the features of NI timing and synchronization devices The NI Sync instrument driver function library is a C DLL This DLL should be linked using the appropriate import library for your application development environment The following sections provide guidelines for creating applications that use the NI Sync driver software 3 Note Ifyou are not using one of the tools listed refer to your development tool reference manual for details on creating applications that call C DLLs Creating a Windows Application Using LabVIEW This section assumes that you are using LabVIEW 8 6 or later to manage your code development and are familiar with the LabVIEW environment basics Developing an Nl Sync Application To develop an NI Sync application with LabVIEW complete the following steps 1 Open an existing or new LabVIEW VI 2 From the Function Palette locate the NI Sync VIs at Instrument I O Instrument Drivers NI Sync 3 Select the VIs you want to use and drop them on the block diagram to build your application National Instruments Corporation 2 1 NI Sync User Manual Chapter 2 Building and Programming Applications Example Programs You can find LabVIEW example programs in the LabVIEW Example Finder Navigate to Help Find Examples and browse Hardware Input and Output Timing and Synchronization or search for the keyword NI Sync Creating a Windows Application Using LabWindows CVI
37. only memory ROM that can be erased with an electrical signal and reprogrammed Electrostatic discharge The basic unit of rate measured in events or oscillations per second using a frequency counter or spectrum analyzer Frequency is the reciprocal of the period of a signal A number that specifies the frequency The physical front panel of an instrument or other hardware NI Sync User Manual Glossary G GPS Hz IEEE 1588 IP jitter L LabVIEW LED NI Sync User Manual Global Positioning System a system of satellites that broadcast accurate times GPS receivers acquire these times which you can use to establish geographic position You can also use the time received as an accurate clock source Hertz the number of scans read or updates written per second The IEEE specification that describes a synchronization protocol for clocks of multiple devices connected through a network Inch or inches Internet Protocol a packet based protocol used to communicate between multiple computer systems on a network The IP is a low level protocol on top of which other more reliable protocols are often defined The rapid variation of a clock or sampling frequency from an ideal constant frequency A graphical programming language Light Emitting Diode a semiconductor light source G 4 ni com master Measurement amp Automation Explorer MAX N NI DAQ NIC NTP 0 OCXO oscillato
38. r output impedance Glossary The requesting or controlling device in a master slave configuration A controlled centralized configuration environment that allows you to configure all of your National Instruments DAQ GPIB IMAQ IVI Motion VISA and VXI devices National Instruments driver software for DAQ hardware Network Interface Card a device that connects a computer system to a network Network Time Protocol a protocol that synchronizes the clocks of computers connected through an IP network You may use NTP to synchronize computer clocks over a very wide geographical area Oven controlled crystal oscillator A device that generates a fixed frequency signal An oscillator most often generates signals by using oscillating crystals but may also use tuned networks lasers or atomic clock sources The most important specifications on oscillators are frequency accuracy frequency stability and phase noise The measured resistance and capacitance between the output terminals of a circuit 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 work stations it offers a theoretical maximum transfer rate of 132 Mbytes s PFI Programmable Function Interface O National Instruments Corporation G 5 NI Sync User Manual Glossary PLL precision propagation delay PTP
39. re Trigger Terminals Use the following VI or function to disconnect software trigger terminals LabVIEW VI C Function niSync Disconnect niSync_DisconnectSWTrigFromTerminal Software Trigger 3 Note A special terminal value exists for disconnecting multiple terminals from a source or destination terminal Use the AllConnected terminal NISYNC_VAL_ALL_CONNECTED to disconnect multiple sources or destinations If this value is supplied as the source and destination terminal all connections of the specified terminal type are disconnected 3 Note In addition to the explicit disconnect VIs and functions niSync Reset disconnects all connected terminals as part of a board reset Close When your program finishes terminate the session with the Close VI or function LabVIEW VI C Function niSync Close nisync_close The Close VI or function is essential for deallocating memory and freeing other operating system resources Every session you initialize must be closed even if an error occurs during program execution While debugging your application it is possible to abort the application without calling Close While aborting execution should not cause problems it is not recommended for terminating your application National Instruments Corporation 2 13 NI Sync User Manual Chapter 2 Building and Programming Applications lay Note Calling Close will not disconnect terminals that were connected whil
40. s are characterized by a source terminal destination terminal and route properties such as inversion and synchronization Check your hardware user manual to see if your hardware supports these additional routing features The following VI and function deal with trigger terminal connections LabVIEW VI C Function niSync Connect niSync_ConnectTrigTerminals Trigger Terminals O National Instruments Corporation 2 7 NI Sync User Manual Chapter 2 Building and Programming Applications Software Trigger Terminals Software trigger terminals include those terminals associated with software initiated trigger pulses The Global Software Trigger terminal can be connected to any other trigger terminal PXI_Trig PXI_Star PXIe_DStarB PFI and PFI_LVDS Once connected to destinations you can initiate a hardware pulse that is then routed to all destinations Typical uses of the Global Software Trigger include the following e Generating a trigger signal to start data acquisition e Generating a sync pulse to align common clocks on multiple chassis e Resetting clocks or divided clocks to synchronize clock generation across multiple timing modules Software trigger terminal connections are characterized by a source terminal Global Software Trigger a destination terminal any valid trigger terminal destination and a synchronization clock In addition the software trigger signal can be inverted synchronized to the r
41. s directly over point to point connections such as PXI_Star or PXIe_DStarA to avoid possible bus loading signal integrity issues over shared trigger buses such as PXI_Trig You can use PXI_Trig if a clean clock such as PXI_CLK10 or an onboard clock governs the ultimate acting on the signal Refer to your hardware user manual for a complete discussion of trigger terminals Star and DStar triggers may not correlate to slots as expected You should refer to your chassis manual for more information on routing star triggers You can use trigger terminals to route single digital pulses between chassis In addition trigger terminals can carry and distribute clock signals Typical uses of trigger terminals include the following e Sharing a trigger signal to start data acquisition between multiple chassis e Sharing a sync pulse to align common clocks on multiple chassis e Distributing high speed clock signals typically over the matched trace length PXI_Star and PXIe_DStarA synchronized lines 3 Note Some destination terminals are part of a shared bus and should not be driven by multiple signal sources NI driver software implements reservation of shared resources including PXI_Trig terminals so that only one source is active on a destination at any given time This reservation software integrates with other NI measurements software For more information refer to KnowledgeBase article 3TJDOND8 at ni com support Trigger terminal connection
42. s the following NI Sync instrument driver API and device driver e Example software for signal based using clocks and triggers directly and time based using time protocols synchronization When developing your application refer to Chapter 2 Building and Programming Applications for information about creating an application with your specific application development environment ADE Also refer to the appropriate hardware specific chapter in this manual for specific examples of using NI Sync with your application National Instruments Corporation 1 1 NI Sync User Manual Chapter 1 Introduction Installation and Configuration Supported Devices and Platforms NI Sync supports Windows XP 32 bit Windows Vista x86 Windows Vista x64 Windows 7 32 bit Windows 7 64 bit LabVIEW RT 8 6 or later Application Software and Programming Language Support Table 1 1 lists the application software versions that NI Sync supports If you are not using National Instruments application software refer to Table 1 2 Table 1 1 National Instruments Application Software Support NI Application Software Versions NI Sync Supports LabVIEW 8 6 or later LabVIEW RT Module 8 6 or later LabWindows CVI 7 0 or later Table 1 2 lists additional programming languages supported by NI Sync Table 1 2 Additional Programming Language Support Programming Language Versions NI Sync Supports ANSI
43. se the National Instruments niSync timing devices to perform the following synchronized distributed measurement and automation tasks Read the current time Create future time events Time stamp triggers and pulse trains e Create synchronized clocks NI Sync User Manual 3 6 ni com Technical Support and Professional Services Visit the following sections of the award winning National Instruments Web site at ni com for technical support and professional services O National Instruments Corporation Support Technical support at ni com support includes the following resources Self Help Technical Resources For answers and solutions visit ni com support for software drivers and updates a searchable KnowledgeBase product manuals step by step troubleshooting wizards thousands of example programs tutorials application notes instrument drivers and so on Registered users also receive access to the NI Discussion Forums at ni com forums NI Applications Engineers make sure every question submitted online receives an answer Standard Service Program Membership This program entitles members to direct access to NI Applications Engineers via phone and email for one to one technical support as well as exclusive access to eLearning training modules at ni com eLearning NI offers complementary membership for a full year after purchase after which you may renew to continue your benefits For information about other te
44. session returned from Initialize may be used in multiple program threads Configure Hardware Use Configuration VIs LabVIEW property nodes or functions to adjust settings of the timing and synchronization features of the timing module including ADC input threshold voltage levels DDS frequency synchronization clock sources specific time reference properties and other settings and features Attributes are configured using a LabVIEW property node or the niSync_SetAttribute and niSync_GetAttribute functions Accessing Attributes In LabVIEW you can find NI Sync attributes in the niSynce property node To access these attributes complete the following steps 1 Open a VI 2 Make sure you are viewing the block diagram Navigate to the niSync palette at Measurement I O NI Sync and drag the property node to the block diagram National Instruments Corporation 2 5 NI Sync User Manual Chapter 2 Connect Terminals NI Sync User Manual Building and Programming Applications 3 Left click the property node and select the attribute you want to use 4 To configure additional attributes resize the property node In C attributes are accessed with the niSync_SetAttribute and niSync_GetAttribute functions These functions correspond to a particular data type For example to set the PFIO DAC voltage level type ViReal64 use nisync_SetAttributeViReal64 Refer to the NI Sync API Reference for a complete list of attribu
45. ssis in which a card or module can be installed Sub Miniature Type A a small coaxial signal connector that features a threaded connection G 6 ni com SMB synchronous T tCtoQ thold tod setup TAI TRIG trigger UTC VI National Instruments Corporation G 7 Glossary Sub Miniature Type B a small coaxial signal connector that features a snap coupling for fast connection A property of an event that is synchronized to a reference clock Clock to output time Hold time Propagation delay time Setup time International Atomic Time Unlike UTC TAI does not account for leap seconds Therefore TAI is the time system employed by network standards for which leap seconds may be problematic Trigger signal A digital signal that starts or times a hardware event for example starting a data acquisition operation Coordinated Universal Time the time system that accounts for leap seconds and is employed by many network standards including NTP Volts Virtual instrument NI Sync User Manual Index Numerics 1588 3 3 IEEE 1588 2008 protocol 3 3 A accessing attributes 2 5 advanced features of NI Sync 2 15 application software support 1 2 applications building and programming 2 1 C calibration certificate NI resources A 1 clearing a clock 2 12 clearing future time events 2 11 clock terminals connecting 2 6 disconnecting 2 12 closing a session 2 13 config
46. t 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 National Instruments respects the intellectual property of others and we ask our users to do the same NI software is protected by copyright and other intellectual property laws Where NI software may be used to reproduce software or other materials belonging to others you may use NI software only to reproduce materials that you may reproduce in accordance with the terms of any applicable license or other legal restriction Trademarks CVI National Instruments NI ni com and LabVIEW are trademarks of National Instruments Corpora
47. tes You can route signals between terminals using the Connect Terminals functions Connecting terminals forms the core of typical NI Sync applications Source and destination terminals can be connected using a variety of mechanisms NI Sync considers three types of terminals clock terminals trigger terminals and software trigger terminals Clock Terminals Clock terminals include terminals associated with the 10 MHz PXI reference clock PXI_CIk10 Clock terminal connections are used to route clock signals between the backplane and front panel of the module Refer to your hardware user manual for a complete discussion of clock terminals Clock terminal connections have a variety of uses including e Multichassis PXI_CIk10 synchronization e PXI_CIk10 replacement with a precise onboard or external oscillator Clock terminal connections are characterized by source and destination terminals The following VI and function deal with clock terminal connections LabVIEW VI C Function niSync Connect niSync_ConnectClkTerminals Clock Terminals 2 6 ni com Chapter 2 Building and Programming Applications Trigger Terminals Trigger terminals include terminals associated with hardware trigger lines Trigger terminals can also carry clocks but they are not associated with any specific clock signal Refer to your hardware user manual for a complete discussion of trigger terminals ay Notes You should route clock
48. tion Refer to the Terms of Use section on ni com legal for more information about National Instruments trademarks The mark LabWindows is used under a license from Microsoft Corporation Windows is a registered trademark of Microsoft Corporation in the United States and other countries Other product and company names mentioned herein are trademarks or trade names of their respective companies Members of the National Instruments Alliance Partner Program are business entities independent from National Instruments and have no agency partnership or joint venture relationship with National Instruments Patents For patents covering National Instruments products technology refer to the appropriate location Help Patents in your software the patents txt file on your media or the National Instruments Patent Notice at ni com patents Export Compliance Information Refer to the Export Compliance Information at ni com 1legal export compliance for the National Instruments global trade compliance policy and how to obtain relevant HTS codes ECCNs and other import export data 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 AP
49. tions with NI Sync bold italic monospace The following conventions appear in this manual The symbol leads you through nested menu items and dialog box options to a final action The sequence Options Settings General directs you to pull down the Options menu select the Settings item and select General from the last dialog box This icon denotes a note which alerts you to important information This icon denotes a caution which advises you of precautions to take to avoid injury data loss or a system crash 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 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 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 National Instruments Corporation vii NI Sync User Manual About This Manual Related Documentation NI Sync User Manual The following documents contain information that you might find helpful as you read this manual PICM
50. uration 1 1 device and system 1 3 configuring hardware 2 5 measurements 2 10 connecting terminals 2 6 conventions used in the manual vii creating a clock 2 10 creating a future time event 2 9 creating Windows application using LabVIEW developing NI Sync application 2 1 example programs 2 2 using LabWindows CVI developing NI Sync application 2 2 example programs 2 2 National Instruments Corporation 1 1 D developing NI Sync application 2 1 2 2 device configuration 1 3 diagnostic tools NI resources A 1 disabling a time stamp trigger 2 11 disconnecting terminals 2 12 distributed time technology overview 3 1 documentation conventions used in manual vii NI resources A 1 related documentation viii drivers NI resources A 1 E enabling a time stamp trigger 2 10 example NI Sync programs for creating a Windows application using LabVIEW 2 2 using LabWindows CVI 2 2 examples NI resources A 1 F FPGA reconfiguration 2 15 frequency measurement 2 15 G getting time 2 9 GPS 3 3 synchronization accuracy factors affecting 3 4 synchronizing to GPS time 3 3 NI Sync User Manual Index H help technical support A 1 IEEE 1588 2008 protocol 3 3 initializing 2 5 installation 1 1 software 1 2 instrument drivers NI resources A 1 introduction 1 1 IRIG 3 5 standard 200 04 3 5 K KnowledgeBase A 1 L LabVIEW creating Windows application using 2 1 LabWindo
51. user manual for more information 3 Note The NI PCI 1588 and NI PXI 6682H devices are actually two devices a timing and synchronization device and a Network Interface Card NIC In the Windows Device Manager the timing and synchronization devices are enumerated in the Data Acquisition Devices section as NI PCI 1588 or NI PXI 6682 H The NIC is enumerated in the Network adapters section as AMD PCNET Family PCI Ethernet Adapter When configuring your network connections in Windows the local area connection associated with the AMD PCNET Family PCI Ethernet Adapter is the one associated with the timing and synchronization device Using Measurement amp Automation Explorer Measurement amp Automation Explorer MAX is a Windows based application for configuring and viewing National Instruments device settings on Windows operating systems Locating Your NI Timing and Synchronization Devices Your NI timing modules appear in MAX under My System Devices and Interfaces From this location you can launch test panels perform self tests and view properties of your devices Once you have identified your PXI system components you also can locate your NI timing devices by National Instruments Corporation 1 3 NI Sync User Manual Chapter 1 Introduction Installation and Configuration browsing the PXI System view My System Devices and Interfaces PXI System Refer to Figure 1 1 for an example of the type of device information available
52. ws CVI creating Windows application using 2 2 MAX See Measurement amp Automation Explorer Measurement amp Automation Explorer locating NI timing and synchronization devices with 1 3 NI PXI 665x device information in figure 1 4 using 1 3 measurements configuring and performing 2 10 NI Sync User Manual 1 2 National Instruments support and services A 1 NI PCI 1588 device information in Windows Device Manager note 1 3 NI PXI 665x device information in MAX figure 1 4 NI Sync about 1 1 application software support 1 2 developing Windows application using LabVIEW 2 1 using LabWindows CVI 2 2 installing 1 2 instrument driver API 2 1 introduction 1 1 programming applications 2 1 programming flow 2 3 advanced features 2 15 FPGA reconfiguration 2 15 frequency measurement 2 15 clearing a clock 2 12 clearing future time events 2 11 closing 2 13 configuring and performing measurements 2 10 configuring hardware 2 5 accessing attributes 2 5 connecting terminals 2 6 clock terminals 2 6 software trigger terminals 2 8 trigger terminals 2 7 creating a clock 2 10 creating a future time event 2 9 disabling a time stamp trigger 2 11 ni com disconnecting terminals 2 12 clock terminals 2 12 software trigger terminals 2 13 trigger terminals 2 13 enabling a time stamp trigger 2 10 getting time 2 9 initializing 2 5 NI PCL 1588 figure 2 4 NI PXI 665x figure 2 3 NI PXI 6682H
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