National Instruments NI 6238 Manual de usuario

DAQ M SeriesNI 6238/6239 User ManualIsolated Current Input/Current Output DevicesNI 6238/6239 User ManualJuly 2006371913A-01

ContentsNI 6238/6239 User Manual x ni.comChapter 8PFIUsing PFI Terminals as Timing Input Signals ...

Chapter 7 Counters© National Instruments Corporation 7-35 NI 6238/6239 User ManualFigure 7-30. PrescalingPrescaling is intended to be used for freque

Chapter 7 CountersNI 6238/6239 User Manual 7-36 ni.comFigure 7-31. Duplicate Count Prevention ExampleOn the first rising edge of the Gate, the curren

Chapter 7 Counters© National Instruments Corporation 7-37 NI 6238/6239 User ManualFigure 7-32. Duplicate Count ExampleExample Application That Preven

Chapter 7 CountersNI 6238/6239 User Manual 7-38 ni.comcounter value and Counter n Internal Output signals change synchronously to the 80 MHz Timebase.

Chapter 7 Counters© National Instruments Corporation 7-39 NI 6238/6239 User ManualOtherwise, the mode depends on the signal that drives Counter n Sour

Chapter 7 CountersNI 6238/6239 User Manual 7-40 ni.comFigure 7-35. Other Internal Source ModeExternal Source ModeIn external source mode, the device

© National Instruments Corporation 8-1 NI 6238/6239 User Manual8PFINI 6238/6239 devices have 10 Programmable Function Interface (PFI) signals—six inpu

Chapter 8 PFINI 6238/6239 User Manual 8-2 ni.comFigure 8-2. NI 6238/6239 PFI Output CircuitryWhen a terminal is used as a timing input or output sign

Chapter 8 PFI© National Instruments Corporation 8-3 NI 6238/6239 User ManualExporting Timing Output Signals Using PFI TerminalsYou can route any of th

Chapter 8 PFINI 6238/6239 User Manual 8-4 ni.comFigure 8-3. PFI Input Signals ConnectionsPFI FiltersYou can enable a programmable debouncing filter o

Contents© National Instruments Corporation xi NI 6238/6239 User ManualChapter 11Bus InterfaceDMA Controllers ...

Chapter 8 PFI© National Instruments Corporation 8-5 NI 6238/6239 User ManualThe filter setting for each input can be configured independently. On powe

Chapter 8 PFINI 6238/6239 User Manual 8-6 ni.comConsult the device specifications for details. However, you should avoid these fault conditions by fol

Chapter 8 PFI© National Instruments Corporation 8-7 NI 6238/6239 User ManualFigure 8-5. NI 6238 Digital I/O Connections (DO Source)P1.<0..3>P1.

Chapter 8 PFINI 6238/6239 User Manual 8-8 ni.comFigure 8-6. NI 6239 Digital I/O Connections (DO Sink)Caution Exceeding the maximum input voltage or

© National Instruments Corporation 9-1 NI 6238/6239 User Manual9Isolation and Digital IsolatorsNI 6232/6233 devices are isolated data acquisition devi

Chapter 9 Isolation and Digital IsolatorsNI 6238/6239 User Manual 9-2 ni.comThe non-isolated ground is connected to the chassis ground of the PC or ch

Chapter 9 Isolation and Digital Isolators© National Instruments Corporation 9-3 NI 6238/6239 User Manual• Improved safety—Isolation creates an insulat

© National Instruments Corporation 10-1 NI 6238/6239 User Manual10Digital Routing and Clock GenerationThe digital routing circuitry has the following

Chapter 10 Digital Routing and Clock GenerationNI 6238/6239 User Manual 10-2 ni.comCaution RTSI signals are not isolated from the chassis.80 MHz Tim

Chapter 10 Digital Routing and Clock Generation© National Instruments Corporation 10-3 NI 6238/6239 User Manual10 MHz Reference ClockThe 10 MHz refere

© National Instruments Corporation xiii NI 6238/6239 User ManualAbout This ManualThe NI 6238/6239 User Manual contains information about using the NI

Chapter 10 Digital Routing and Clock GenerationNI 6238/6239 User Manual 10-4 ni.com• Share trigger signals between devicesMany National Instruments DA

Chapter 10 Digital Routing and Clock Generation© National Instruments Corporation 10-5 NI 6238/6239 User ManualUsing RTSI as OutputsRTSI <0..7>

Chapter 10 Digital Routing and Clock GenerationNI 6238/6239 User Manual 10-6 ni.comUsing RTSI Terminals as Timing Input SignalsYou can use RTSI termin

Chapter 10 Digital Routing and Clock Generation© National Instruments Corporation 10-7 NI 6238/6239 User ManualThe filter setting for each input can b

Chapter 10 Digital Routing and Clock GenerationNI 6238/6239 User Manual 10-8 ni.comPXI_CLK10PXI_CLK10 is a common low-skew 10 MHz clock reference cloc

Chapter 10 Digital Routing and Clock Generation© National Instruments Corporation 10-9 NI 6238/6239 User Manualinput on each rising edge of a filter c

Chapter 10 Digital Routing and Clock GenerationNI 6238/6239 User Manual 10-10 ni.comWhen a PFI input is routed directly to RTSI, or a RTSI input is ro

© National Instruments Corporation 11-1 NI 6238/6239 User Manual11Bus InterfaceThe bus interface circuitry of NI 6238/6239 devices efficiently moves d

Chapter 11 Bus InterfaceNI 6238/6239 User Manual 11-2 ni.comEach DMA controller supports packing and unpacking of data through the FIFOs to connect di

Chapter 11 Bus Interface© National Instruments Corporation 11-3 NI 6238/6239 User ManualUsing PXI with CompactPCIUsing PXI-compatible products with st

About This ManualNI 6238/6239 User Manual xiv ni.comitalic Italic text denotes variables, emphasis, a cross-reference, or an introduction to a key con

Chapter 11 Bus InterfaceNI 6238/6239 User Manual 11-4 ni.comInterrupt Request (IRQ)IRQ transfers rely on the CPU to service data transfer requests. Th

© National Instruments Corporation 12-1 NI 6238/6239 User Manual12TriggeringA trigger is a signal that causes an action, such as starting or stopping

Chapter 12 TriggeringNI 6238/6239 User Manual 12-2 ni.comYou also can program your DAQ device to perform an action in response to a trigger from a dig

© National Instruments Corporation A-1 NI 6238/6239 User ManualADevice-Specific InformationThis appendix contains device pinouts, specifications, cabl

Appendix A Device-Specific InformationNI 6238/6239 User Manual A-2 ni.comFigure A-1. NI 6238 PinoutTable A-1. NI 6238 Device Default NI-DAQmx Counte

Appendix A Device-Specific Information© National Instruments Corporation A-3 NI 6238/6239 User ManualNote For more information about default NI-DAQm

Appendix A Device-Specific InformationNI 6238/6239 User Manual A-4 ni.comvision, and motion devices. Since PXI devices use PXI backplane signals for t

Appendix A Device-Specific Information© National Instruments Corporation A-5 NI 6238/6239 User ManualFigure A-2. NI 6239 PinoutTable A-2. NI 6239 De

Appendix A Device-Specific InformationNI 6238/6239 User Manual A-6 ni.comNote For more information about default NI-DAQmx counter inputs, refer to C

Appendix A Device-Specific Information© National Instruments Corporation A-7 NI 6238/6239 User Manualvision, and motion devices. Since PXI devices use

About This Manual© National Instruments Corporation xv NI 6238/6239 User ManualThe C Function Reference Help describes functions and attributes.The NI

© National Instruments Corporation B-1 NI 6238/6239 User ManualBTroubleshootingThis section contains some common questions about M Series devices. If

Appendix B TroubleshootingNI 6238/6239 User Manual B-2 ni.comIn an isolated device, leaving the AI GND terminal unconnected will cause the signal to d

Appendix B Troubleshooting© National Instruments Corporation B-3 NI 6238/6239 User ManualCountersWhen multiple sample clocks on my buffered counter me

© National Instruments Corporation C-1 NI 6238/6239 User ManualCTechnical Support and Professional ServicesVisit the following sections of the Nationa

Appendix C Technical Support and Professional ServicesNI 6238/6239 User Manual C-2 ni.com• Calibration Certificate—If your product supports calibratio

© National Instruments Corporation G-1 NI 6238/6239 User ManualGlossaryNumbers/Symbols% Percent.+ Positive of, or plus.– Negative of, or minus.± Plus

GlossaryNI 6238/6239 User Manual G-2 ni.comAI 1. Analog input.2. Analog input channel signal.AI GND Analog input ground signal.AI SENSE Analog input s

Glossary© National Instruments Corporation G-3 NI 6238/6239 User ManualASIC Application-specific integrated circuit—A proprietary semiconductor compon

GlossaryNI 6238/6239 User Manual G-4 ni.comcascading Process of extending the counting range of a counter chip by connecting to the next higher counte

Glossary© National Instruments Corporation G-5 NI 6238/6239 User Manualcounter 1. Software. A memory location used to store a count of certain occurre

About This ManualNI 6238/6239 User Manual xvi ni.comtools. Refer to the following locations on the Contents tab of the LabVIEW Help for information ab

GlossaryNI 6238/6239 User Manual G-6 ni.comdata transfer A technique for moving digital data from one system to another.Options for data transfer are

Glossary© National Instruments Corporation G-7 NI 6238/6239 User Manualdigital signal A representation of information by a set of discrete values acco

GlossaryNI 6238/6239 User Manual G-8 ni.comFFIFO First-In-First-Out memory buffer—A data buffering technique that functions like a shift register wher

Glossary© National Instruments Corporation G-9 NI 6238/6239 User Manualft Feet.function 1. A built-in execution element, comparable to an operator, fu

GlossaryNI 6238/6239 User Manual G-10 ni.comimpedance 1. The electrical characteristic of a circuit expressed in ohms and/or capacitance/inductance.2.

Glossary© National Instruments Corporation G-11 NI 6238/6239 User ManualKkHz Kilohertz—A unit of frequency; 1 kHz = 103 = 1,000 Hz.kS 1,000 samples.LL

GlossaryNI 6238/6239 User Manual G-12 ni.comMITE MXI Interface To Everything—A custom ASIC designed by National Instruments that implements the PCI bu

Glossary© National Instruments Corporation G-13 NI 6238/6239 User ManualNI-PGIA See instrumentation amplifier.non-referenced signal sourcesSignal sour

GlossaryNI 6238/6239 User Manual G-14 ni.compower source An instrument that provides one or more sources of AC or DC power. Also known as power supply

Glossary© National Instruments Corporation G-15 NI 6238/6239 User Manualreal time 1. Displays as it comes in; no delays.2. A property of an event or s

About This Manual© National Instruments Corporation xvii NI 6238/6239 User Manual.NET Languages without NI Application SoftwareThe NI Measurement Stud

GlossaryNI 6238/6239 User Manual G-16 ni.comSCXI Signal Conditioning eXtensions for Instrumentation—The National Instruments product line for conditio

Glossary© National Instruments Corporation G-17 NI 6238/6239 User Manualsource impedance A parameter of signal sources that reflects current-driving a

GlossaryNI 6238/6239 User Manual G-18 ni.comtrigger 1. Any event that causes or starts some form of data capture.2. An external stimulus that initiate

Glossary© National Instruments Corporation G-19 NI 6238/6239 User ManualVsSignal source voltage.virtual channel See channel.Wwaveform 1. The plot of t

© National Instruments Corporation I-1 NI 6238/6239 User ManualIndexSymbols.NET languages documentation, xviiNumerics10 MHz reference clock, 10-3100 k

IndexNI 6238/6239 User Manual I-2 ni.comtriggering, 5-4troubleshooting, B-2ANSI C documentation, xviiAO FIFO, 5-1AO Pause Trigger signal, 5-6AO Sample

Index© National Instruments Corporation I-3 NI 6238/6239 User Manualconventions used in the manual, xiiiCounter n A signal, 7-29Counter n Aux signal,

IndexNI 6238/6239 User Manual I-4 ni.comdigitalinput and output, 6-1isolation, 9-3isolators, 9-1routing, 10-1signals, connecting, 6-2, 8-6source, trig

Index© National Instruments Corporation I-5 NI 6238/6239 User Manualnon-buffered hardware-timed, 5-3pulse for ETS, 7-25pulse train, 7-23retriggerable

IndexNI 6238/6239 User Manual I-6 ni.comusing quadrature encoders, 7-16using two pulse encoders, 7-18measuringhigh frequency with two counters, 7-12la

© National Instruments Corporation 1-1 NI 6238/6239 User Manual1Getting StartedM Series NI 6238/6239 devices feature eight differential analog input (

Index© National Instruments Corporation I-7 NI 6238/6239 User Manualpulse-width measurement, 7-6buffered, 7-6single, 7-6PXIand PXI Express, 11-2clock,

IndexNI 6238/6239 User Manual I-8 ni.comCounter n Z, 7-29counter timing, 7-26counters, 7-26exporting timing output using PFI terminals, 8-3FREQ OUT, 7

Index© National Instruments Corporation I-9 NI 6238/6239 User ManualUusing PFI terminalsas static digital I/Os, 8-3as timing input, 8-2to export timin

Chapter 1 Getting StartedNI 6238/6239 User Manual 1-2 ni.comDevice SpecificationsRefer to the NI 6238/6239 Specifications, available on the NI-DAQ Dev

© National Instruments Corporation 2-1 NI 6238/6239 User Manual2DAQ System OverviewFigure 2-1 shows a typical DAQ system, which includes sensors, tran

SupportWorldwide Technical Support and Product Informationni.comNational Instruments Corporate Headquarters11500 North Mopac Expressway Austin, Texas

Chapter 2 DAQ System OverviewNI 6238/6239 User Manual 2-2 ni.comFigure 2-2. General NI 6238/6239 Block DiagramDAQ-STC2The DAQ-STC2 implements a high-

Chapter 2 DAQ System Overview© National Instruments Corporation 2-3 NI 6238/6239 User ManualCalibration CircuitryThe M Series analog inputs and output

Chapter 2 DAQ System OverviewNI 6238/6239 User Manual 2-4 ni.comCables and AccessoriesNI offers a variety of products to use with NI 6238/6239 devices

Chapter 2 DAQ System Overview© National Instruments Corporation 2-5 NI 6238/6239 User ManualProgramming Devices in SoftwareNational Instruments measur

© National Instruments Corporation 3-1 NI 6238/6239 User Manual3Connector InformationThe I/O Connector Signal Descriptions and RTSI Connector Pinout s

Chapter 3 Connector InformationNI 6238/6239 User Manual 3-2 ni.comAO GND — — Analog Output Ground—AO GND is the reference for AO <0..1>. AI GND

Chapter 3 Connector Information© National Instruments Corporation 3-3 NI 6238/6239 User ManualRTSI Connector PinoutRefer to the RTSI Connector Pinout

© National Instruments Corporation 4-1 NI 6238/6239 User Manual4Analog InputFigure 4-1 shows the analog input circuitry of NI 6238 and NI 6239 devices

Chapter 4 Analog InputNI 6238/6239 User Manual 4-2 ni.comfor all input ranges. The NI-PGIA can amplify or attenuate an AI signal to ensure that you us

Chapter 4 Analog Input© National Instruments Corporation 4-3 NI 6238/6239 User ManualM Series devices use a calibration method that requires some code

Important InformationWarrantyThe NI 6238/6239 is warranted against defects in materials and workmanship for a period of three years from the date of

Chapter 4 Analog InputNI 6238/6239 User Manual 4-4 ni.comFigure 4-2. Analog Current Input Connection Method 1Method 2Method 2, shown in Figure 4-3, t

Chapter 4 Analog Input© National Instruments Corporation 4-5 NI 6238/6239 User ManualNote that AI GND must always be connected to some voltage level.

Chapter 4 Analog InputNI 6238/6239 User Manual 4-6 ni.comFigure 4-5. NI 6238/6239 PGIAAnalog input ground-reference setting refers to the reference t

Chapter 4 Analog Input© National Instruments Corporation 4-7 NI 6238/6239 User ManualCaution The maximum input voltages rating of AI signals with re

Chapter 4 Analog InputNI 6238/6239 User Manual 4-8 ni.comMultichannel Scanning ConsiderationsM Series devices can scan multiple channels at high rates

Chapter 4 Analog Input© National Instruments Corporation 4-9 NI 6238/6239 User ManualFor example, suppose all channels in a system use a –20 to 20 mA

Chapter 4 Analog InputNI 6238/6239 User Manual 4-10 ni.comAnalog Input Data Acquisition MethodsWhen performing analog input measurements, you either c

Chapter 4 Analog Input© National Instruments Corporation 4-11 NI 6238/6239 User Manualsamples has been written out, the generation stops. If you use a

Chapter 4 Analog InputNI 6238/6239 User Manual 4-12 ni.commainly to AI signal routing to the device, although they also apply to signal routing in gen

Chapter 4 Analog Input© National Instruments Corporation 4-13 NI 6238/6239 User ManualM Series devices use ai/SampleClock and ai/ConvertClock to perfo

NATIONAL INSTRUMENTS PRODUCTS ARE INCORPORATED IN A SYSTEM OR APPLICATION, INCLUDING, WITHOUT LIMITATION, THE APPROPRIATE DESIGN, PROCESS AND SAFETY L

Chapter 4 Analog InputNI 6238/6239 User Manual 4-14 ni.comWhen this calculation results in the sampling rate exceeding 35 kHz, there is not enough tim

Chapter 4 Analog Input© National Instruments Corporation 4-15 NI 6238/6239 User Manualexample, four. The value decrements with each pulse on ai/Sample

Chapter 4 Analog InputNI 6238/6239 User Manual 4-16 ni.comYou can specify an internal or external source for ai/SampleClock. You also can specify whet

Chapter 4 Analog Input© National Instruments Corporation 4-17 NI 6238/6239 User ManualOther Timing RequirementsYour DAQ device only acquires data duri

Chapter 4 Analog InputNI 6238/6239 User Manual 4-18 ni.com•RTSI <0..7>• Input PFI <0..5>•PXI_STARai/SampleClockTimebase is not available a

Chapter 4 Analog Input© National Instruments Corporation 4-19 NI 6238/6239 User Manualfinished. It then reloads itself in preparation for the next ai/

Chapter 4 Analog InputNI 6238/6239 User Manual 4-20 ni.comFigure 4-12. ai/SampleClock and ai/ConvertClockOther Timing RequirementsThe sample and conv

Chapter 4 Analog Input© National Instruments Corporation 4-21 NI 6238/6239 User ManualFigure 4-13. Single External Signal Driving ai/SampleClock and

Chapter 4 Analog InputNI 6238/6239 User Manual 4-22 ni.comAI Start Trigger SignalUse the AI Start Trigger (ai/StartTrigger) signal to begin a measurem

Chapter 4 Analog Input© National Instruments Corporation 4-23 NI 6238/6239 User Manualcomplete description of the use of ai/StartTrigger and ai/Refere

© National Instruments Corporation v NI 6238/6239 User ManualContentsAbout This ManualConventions ...

Chapter 4 Analog InputNI 6238/6239 User Manual 4-24 ni.comUsing a Digital SourceTo use ai/ReferenceTrigger with a digital source, specify a source and

Chapter 4 Analog Input© National Instruments Corporation 4-25 NI 6238/6239 User ManualRouting AI Pause Trigger Signal to an Output TerminalYou can rou

© National Instruments Corporation 5-1 NI 6238/6239 User Manual5Analog OutputNI 6238/6239 devices have two AO channels controlled by a single clock an

Chapter 5 Analog OutputNI 6238/6239 User Manual 5-2 ni.comDACs. It allows you to download the points of a waveform to your M Series device without hos

Chapter 5 Analog Output© National Instruments Corporation 5-3 NI 6238/6239 User ManualNon-BufferedIn non-buffered acquisitions, data is written direct

Chapter 5 Analog OutputNI 6238/6239 User Manual 5-4 ni.comthe buffer at a fast enough rate to keep up with the generation, the buffer will underflow a

Chapter 5 Analog Output© National Instruments Corporation 5-5 NI 6238/6239 User ManualMaximum Working Voltage section of the NI 6238/6239 Specificatio

Chapter 5 Analog OutputNI 6238/6239 User Manual 5-6 ni.comUsing a Digital SourceTo use ao/StartTrigger, specify a source and an edge. The source can b

Chapter 5 Analog Output© National Instruments Corporation 5-7 NI 6238/6239 User Manualonboard clock, the generation resumes as soon as the pause trigg

Chapter 5 Analog OutputNI 6238/6239 User Manual 5-8 ni.comYou also can specify whether the samples are paused when ao/PauseTrigger is at a logic high

ContentsNI 6238/6239 User Manual vi ni.comChapter 4Analog InputAnalog Input Circuitry ...

Chapter 5 Analog Output© National Instruments Corporation 5-9 NI 6238/6239 User ManualOther Timing RequirementsA counter on your device internally gen

Chapter 5 Analog OutputNI 6238/6239 User Manual 5-10 ni.comao/SampleClockTimebase is not available as an output on the I/O connector.You might use ao/

© National Instruments Corporation 6-1 NI 6238/6239 User Manual6Digital Input and OutputNI 6238/6239 devices have six static digital input lines, P0.&

Chapter 6 Digital Input and OutputNI 6238/6239 User Manual 6-2 ni.comConnecting Digital I/O SignalsThe DI signals P0.<0..5> are referenced to P0

Chapter 6 Digital Input and Output© National Instruments Corporation 6-3 NI 6238/6239 User ManualFigure 6-2. NI 6239 Digital I/O Connections (DO Sink

Chapter 6 Digital Input and OutputNI 6238/6239 User Manual 6-4 ni.comGetting Started with DIO Applications in SoftwareYou can use NI 6238/6239 devices

© National Instruments Corporation 7-1 NI 6238/6239 User Manual7CountersNI 6238/6239 devices have two general-purpose 32-bit counter/timers and one fr

Chapter 7 CountersNI 6238/6239 User Manual 7-2 ni.comFigure 7-1. M Series CountersThe counters have seven input signals, although in most application

Chapter 7 Counters© National Instruments Corporation 7-3 NI 6238/6239 User ManualCounter Input ApplicationsCounting EdgesIn edge counting applications

Chapter 7 CountersNI 6238/6239 User Manual 7-4 ni.comFigure 7-3. Single Point (On-Demand) Edge Counting with Pause TriggerBuffered (Sample Clock) Edg

Contents© National Instruments Corporation vii NI 6238/6239 User ManualAI Pause Trigger Signal ...

Chapter 7 Counters© National Instruments Corporation 7-5 NI 6238/6239 User ManualNon-Cumulative Buffered Edge CountingNon-cumulative edge counting is

Chapter 7 CountersNI 6238/6239 User Manual 7-6 ni.comPulse-Width MeasurementIn pulse-width measurements, the counter measures the width of a pulse on

Chapter 7 Counters© National Instruments Corporation 7-7 NI 6238/6239 User ManualThe counter counts the number of edges on the Source input while the

Chapter 7 CountersNI 6238/6239 User Manual 7-8 ni.comSingle Period MeasurementWith single period measurement, the counter counts the number of rising

Chapter 7 Counters© National Instruments Corporation 7-9 NI 6238/6239 User ManualFigure 7-9. Buffered Period MeasurementNote that if you are using an

Chapter 7 CountersNI 6238/6239 User Manual 7-10 ni.comBuffered Semi-Period MeasurementIn buffered semi-period measurement, on each edge of the Gate si

Chapter 7 Counters© National Instruments Corporation 7-11 NI 6238/6239 User ManualYou can route the signal to measure (F1) to the Gate of a counter. Y

Chapter 7 CountersNI 6238/6239 User Manual 7-12 ni.comFigure 7-12. Method 1bMethod 2—Measure High Frequency with Two CountersIn this method, you meas

Chapter 7 Counters© National Instruments Corporation 7-13 NI 6238/6239 User ManualFigure 7-13. Method 2Method 3—Measure Large Range of Frequencies Us

Chapter 7 CountersNI 6238/6239 User Manual 7-14 ni.comFigure 7-14. Method 3Then route the Counter 0 Internal Output signal to the Gate input of Count

ContentsNI 6238/6239 User Manual viii ni.comChapter 7CountersCounter Input Applications ...

Chapter 7 Counters© National Instruments Corporation 7-15 NI 6238/6239 User Manual80 MHz Timebase. Your measurement may return 1600 ±1 cycles dependin

Chapter 7 CountersNI 6238/6239 User Manual 7-16 ni.comFor information on connecting counter signals, refer to the Default Counter Terminals section.Po

Chapter 7 Counters© National Instruments Corporation 7-17 NI 6238/6239 User ManualFigure 7-15. X1 EncodingX2 EncodingThe same behavior holds for X2 e

Chapter 7 CountersNI 6238/6239 User Manual 7-18 ni.comChannel Z behavior—when it goes high and how long it stays high—differs with quadrature encoder

Chapter 7 Counters© National Instruments Corporation 7-19 NI 6238/6239 User ManualFor information on connecting counter signals, refer to the Default

Chapter 7 CountersNI 6238/6239 User Manual 7-20 ni.comFigure 7-20. Single Two-Signal Edge-Separation MeasurementBuffered Two-Signal Edge-Separation M

Chapter 7 Counters© National Instruments Corporation 7-21 NI 6238/6239 User ManualCounter Output ApplicationsSimple Pulse GenerationSingle Pulse Gener

Chapter 7 CountersNI 6238/6239 User Manual 7-22 ni.comFigure 7-23. Single Pulse Generation with Start TriggerRetriggerable Single Pulse GenerationThe

Chapter 7 Counters© National Instruments Corporation 7-23 NI 6238/6239 User ManualPulse Train GenerationContinuous Pulse Train GenerationThis function

Chapter 7 CountersNI 6238/6239 User Manual 7-24 ni.comFrequency GenerationYou can generate a frequency by using a counter in pulse train generation mo

Contents© National Instruments Corporation ix NI 6238/6239 User ManualCounter Timing Signals ...

Chapter 7 Counters© National Instruments Corporation 7-25 NI 6238/6239 User ManualFrequency Output can be routed out to any output PFI <6..9> or

Chapter 7 CountersNI 6238/6239 User Manual 7-26 ni.comfrequency of the system. Figure 7-28 shows an example of pulse generation for ETS; the delay fro

Chapter 7 Counters© National Instruments Corporation 7-27 NI 6238/6239 User Manualperforming. Table 7-3 lists how this terminal is used in various app

Chapter 7 CountersNI 6238/6239 User Manual 7-28 ni.comCounter n Gate SignalThe Counter n Gate signal can perform many different operations depending o

Chapter 7 Counters© National Instruments Corporation 7-29 NI 6238/6239 User Manual• ai/StartTrigger•PXI_STARIn addition, Counter 1 Internal Output, Co

Chapter 7 CountersNI 6238/6239 User Manual 7-30 ni.comwaiting for the Gate signal when it is armed. Counter output operations can use the arm signal i

Chapter 7 Counters© National Instruments Corporation 7-31 NI 6238/6239 User ManualRouting Frequency Output to a TerminalYou can route Frequency Output

Chapter 7 CountersNI 6238/6239 User Manual 7-32 ni.comCounter TriggeringCounters support three different triggering actions—arm start, start, and paus

Chapter 7 Counters© National Instruments Corporation 7-33 NI 6238/6239 User ManualOther Counter FeaturesCascading CountersYou can internally route the

Chapter 7 CountersNI 6238/6239 User Manual 7-34 ni.comThe filter setting for each input can be configured independently. On power up, the filters are