Computer-Based Instruments NI 5102 User Manual High-Speed Digitizer NI 5102 User Manual June 2001 Edition Part Number 321390D-01
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Important Information Warranty The NI 5102 is warranted against defects in materials and workmanship for a period of one year from the date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace equipment that proves to be defective during the warranty period. This warranty includes parts and labor.
Compliance FCC/Canada Radio Frequency Interference Compliance* Determining FCC Class The Federal Communications Commission (FCC) has rules to protect wireless communications from interference. The FCC places digital electronics into two classes. These classes are known as Class A (for use in industrial-commercial locations only) or Class B (for use in residential or commercial locations). Depending on where it is operated, this product could be subject to restrictions in the FCC rules.
Canadian Department of Communications This Class B digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations. Cet appareil numérique de la classe B respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada. Compliance to EU Directives Readers in the European Union (EU) must refer to the Manufacturer's Declaration of Conformity (DoC) for information** pertaining to the CE Mark compliance scheme.
Contents About This Manual Conventions Used in This Manual.................................................................................ix Related Documentation..................................................................................................x Chapter 1 Introduction About Your NI 5102 ......................................................................................................1-1 Acquiring Data with Your NI 5102 ...................................................................
Contents Chapter 4 Hardware Overview I/O Connector ................................................................................................................ 4-2 Signal Connections........................................................................................................ 4-5 Serial Communications Port (AUX) ............................................................... 4-6 Analog Input.......................................................................................................
About This Manual The NI 5102 is an analog input device available in PCI, PXI, ISA, PCMCIA, and USB form factors. This manual describes the installation and operation of these digitizers. Conventions Used in This Manual The following conventions are used in this manual: <> Angle brackets that contain numbers separated by an ellipsis represent a range of values associated with a bit or signal name—for example, DBIO<3..0>.
About This Manual NI 5102 NI 5102 is a generic term that denotes one or more of the NI 5102 (PCI), NI 5102 (PXI), NI 5102 (ISA), NI 5102 (PCMCIA), and NI 5102 (USB) devices. NI 5102 (ISA) Refers to the NI 5102 for ISA bus. NI 5102 (PCI) Refers to the NI 5102 for PCI bus. NI 5102 (PCMCIA) Refers to the NI 5102 for computers with a Type II PCMCIA slot. NI 5102 (PXI) Refers to the NI 5102 for PXI bus. NI 5102 (USB) Refers to NI 5102 for computers that are USB compatible.
1 Introduction This chapter describes the National Instruments (NI) 5102 and lists additional equipment. About Your NI 5102 Thank you for your purchase of an NI 5102. The NI 5102 family consists of five different devices tailored to your choice of bus: the PCI, the PXI, the ISA, the PCMCIA, and the universal serial bus (USB).
Chapter 1 Introduction To improve timing resolution for repetitive signals, you can use random interleaved sampling (RIS) on your NI 5102. This method of sampling allows you to view pretrigger data and achieve an effective sampling rate as high as 1 GS/s, 50 times the real-time sampling rate of the device. Detailed specifications of the NI 5102 devices are in Appendix A, Specifications.
Chapter 1 Scope SFP (Win 2000/NT/ Me/9x) LabVIEW (Win 2000/NT/ Me/9x/3.1) DAQ VI Library C/C++ (Win 2000/NT/ Me/9x) LabWindows/CVI (Win 2000/NT/ Me/9x/3.1) NI-SCOPE Driver API Visual Basic ComponentWorks Introduction Microsoft Excel Measure NI-DAQ Driver Software PCI, PXI (Win 2000/NT/Me/9x/3.1) PCMCIA, ISA, USB (Win 2000/NT/Me/9x) NI 5102 Figure 1-1.
Chapter 1 Introduction NI-SCOPE Driver The NI-SCOPE driver is the preferred choice to program your NI 5102. It provides flexibility and programmability in a standard full-featured instrument-driver format which lets you avoid low-level software calls and which works with LabVIEW, LabWindows/CVI, and conventional languages such as C/C++ and Visual Basic. To help you get started, NI-SCOPE comes with examples you can use or modify.
Chapter 1 Introduction NI 5102 digitizers use only the easy I/O interface under data acquisition in LabWindows/CVI. The easy I/O interface provides limited functionality in CVI. To use the NI 5102 to its full capabilities, use the NI-SCOPE driver as shown in Figure 1-1. Note Measurement Studio contains tools for data acquisition and device control built on NI-DAQ driver software.
Chapter 1 Introduction PXI-specific features, RTSI bus trigger, RTSI Clock, and Serial Communication are implemented on the J2 connector of the CompactPCI bus. Table 1-1 lists the J2 pins used by your NI 5102 (PXI) digitizer, which is compatible with any CompactPCI chassis with a sub-bus that does not drive these lines. Even if the sub-bus is capable of driving these lines, the NI 5102 (PXI) is still compatible as long as those pins on the sub-bus are disabled by default and are never enabled.
2 Installation and Configuration This chapter describes how to unpack, install, and configure your NI 5102.
Chapter 2 Installation and Configuration – NI 5102 (USB) NI 5102 (USB) power supply ❑ Vinyl pouch for storing cables and accessories for the NI 5102 (PCMCIA) only Unpacking ♦ NI 5102 (PCI, PXI, ISA) Your device is shipped in an antistatic package to prevent electrostatic damage to the device. Electrostatic discharge can damage several components on the device.
Chapter 2 Installation and Configuration Installing the NI 5102 There are two main steps involved in installation: ♦ 1. Install the NI-SCOPE driver software. You use this driver to write programs to control your NI 5102 in different application development environments (ADEs). Installing NI-SCOPE also allows you to interactively control your NI 5102 with the Scope Soft Front Panel. 2. Install your NI 5102.
Chapter 2 Installation and Configuration Table 2-1. NI 5102 (USB) LED Patterns LED NI 5102 (USB) State Description On Configured State Your NI 5102 (USB) is configured. Off Off or in the low-power, suspend mode Your NI 5102 (USB) is turned off or in the low-power, suspend mode. 2 Blinks Addressed state This pattern is displayed if the host computer detects your NI 5102 (USB) but cannot configure it because NI-DAQ is not installed properly or because there are no system resources available.
3 Digitizer Basics This chapter explains basic information about using digitizers, including important terminology and use of the probe. Understanding Digitizers To understand how digitizers work, you should be familiar with the Nyquist theorem and how it affects analog bandwidth and sample rate. You should also understand vertical sensitivity, analog-to-digital converter (ADC) resolution, record length, and triggering options.
Chapter 3 Digitizer Basics Analog Bandwidth Analog bandwidth describes the frequency range (in hertz) in which a signal can be digitized accurately. This limitation is determined by the inherent frequency response of the input path—from the tip of the probe to the input of the ADC—which causes loss of amplitude and phase information. Analog bandwidth is the frequency at which the measured amplitude is 3 dB below the actual amplitude of the signal.
Chapter 3 Digitizer Basics Sample Rate Sample rate is the rate at which a signal is sampled and digitized by an ADC. According to the Nyquist theorem, a higher sample rate produces accurate measurement of higher frequency signals if the analog bandwidth is wide enough to let the signal to pass through without attenuation. A higher sample rate also captures more waveform details. Figure 3-3 illustrates a 1 MHz sine wave sampled by a 2 MS/s ADC and a 20 MS/s ADC.
Chapter 3 Digitizer Basics Vertical Sensitivity Vertical sensitivity describes the smallest input voltage change the digitizer can capture. This limitation is because one distinct digital voltage encompasses a range of analog voltages. Therefore, it is possible that a minute change in voltage at the input is not noticeable at the output of the ADC. This parameter depends on the input range, gain of the input amplifier, and ADC resolution. It is specified in volts per least significant bit (V/LSB).
Chapter 3 Digitizer Basics rate of 20 MHz, the duration of acquisition is 5 ms (100,000 × 50 ns). The NI 5102 has a buffer size of 663,000 samples. When performing a single-channel acquisition, you can use the entire available memory to capture data for a duration of 33.1 ms at 20 MS/s. The NI 5102 (PCI, PXI) can transfer data to host memory while acquiring data, thus expanding their single-shot record length to 16 million samples on each channel.
Chapter 3 Digitizer Basics +127 LSB 0 LSB +7 LSB –8 LSB –128 LSB a. Gain = 1, Input Range ±5 V, Number of LSBs = 15 +127 LSB +38.4 LSB 0 LSB –38.4 LSB –128 LSB b. Gain = 5, Input Range ±1 V, Number of LSBs = 77 +153 LSB +127 LSB Acquired Signal 0 LSB –128 LSB –154 LSB c. Gain = 20, Input Range ±250 mV, Number of LSBs = 307.2 Figure 3-5.
Chapter 3 Digitizer Basics buffering. See the Understanding the Probe and Its Effects on Your Waveform section later in this chapter for more information. In addition to the input resistance, all digitizers, DSOs, and probes present some input capacitance in parallel with the resistance. This capacitance can interfere with your measurement in much the same way as the resistance does. You can reduce this capacitance by using an attenuating probe (X10, X100, or X1000) or an active probe.
Chapter 3 Digitizer Basics Understanding the Probe and Its Effects on Your Waveform Signals travel from the tip of the probe to the input amplifier and are then digitized by the ADC. This signal path makes the probe an important electrical system component that can severely affect the accuracy of the measurement. A probe can potentially influence measured amplitude and phase, and the signal can pick up additional noise on its way to the input stage.
Chapter 3 Digitizer Basics Analytically, obtaining a flat frequency response means: Rin/(Rin + Rp) = Cp/(Cp + Cin + Cc) It can be shown that: Rin(Cin + Cc) = CpRp or the time constant of the probe equals the time constant of the digitizer input. How to Compensate Your Probe Adjusting the tunable probe capacitor to get a flat frequency response is called probe compensation. On the NI 5102, you can select a 0–5 V, 1 kHz pulse train as reference to output on PFI1 or PFI2.
Chapter 3 Digitizer Basics CH0 CH1 BNC Probe TRIG PFI1 PFI2 SMB 100 BNC Adapter NI 5102 (PCI, ISA) I/O Connectors Figure 3-7. Connecting the Probe Compensation Cabling As shown in Figure 3-8, an undercompensated probe attenuates higher frequency signals, whereas an overcompensated probe amplifies higher frequencies. Calibrate your probe frequently to ensure accurate measurements from your NI 5102. NI 5102 User Manual 3-10 ni.
Chapter 3 Probe Adjustment Signal Probe Adjustment Signal Probe Adjustment Signal Proper Amplitude of a 1 MHz Test Signal Reduced Amplitude of a 1 MHz Test Signal Increased Amplitude of a 1 MHz Test Signal a. Compensated Correctly b. Undercompensated c. Overcompensated Digitizer Basics Figure 3-8. Probe Compensation Comparison Active and Current Probes You can also use active probes and current probes with digitizers and DSOs.
4 Hardware Overview This chapter includes an overview of the NI 5102, explains the operation of each functional unit making up your NI 5102, and describes the signal connections. Figure 4-1 shows a block diagram of the NI 5102 (PCI, PXI, ISA).
Chapter 4 Hardware Overview Figure 4-2 shows a block diagram of the NI 5102 (PCMCIA, USB).
Chapter 4 Hardware Overview The NI 5102 (PCI, ISA) gives you direct BNC connectivity on the bracket, as shown in Figure 4-3. CH0 CH1 TRIG PFI1 PFI2 Figure 4-3. NI 5102 (PCI, ISA) I/O Connectors Use the cable assembly provided for these connections on the NI 5102 (PCMCIA), as shown in Figure 4-4. CH0 CH1 PFI1 TRIG PFI2 PFI1 CH0 CH1 TRIG PFI2 Figure 4-4.
Chapter 4 Hardware Overview The NI 5102 (USB) gives you direct BNC connectivity, as shown in Figure 4-5. Figure 4-5. NI 5102 (USB) I/O Connectors ♦ NI 5102 (PXI) The NI 5102 (PXI) has two standard BNC female connectors for CH0 and CH1 analog input connections, one standard BNC female connector for the TRIG channel, one standard SMB female connector for a multipurpose digital timing and triggering signal, PFI1, and a 9-pin mini-DIN connector, AUX, for serial communication or PFI2.
Chapter 4 Hardware Overview PFI1 AUX C H 0 C H 1 T R I G NI 5102 Figure 4-6. NI 5102 (PXI) I/O Connectors Signal Connections You can use CH0 and CH1 to digitize data as well as to trigger an acquisition. Use the TRIG channel for an external analog trigger only; data on the TRIG channel cannot be digitized. PFI1 and PFI2 are digital signals that you can use for timing-critical applications. When used as inputs, PFI lines can trigger an acquisition and/or allow an external scan clock connection.
Chapter 4 Hardware Overview Serial Communications Port (AUX) ♦ NI 5102 (PXI) The serial communication port, AUX, provides +5V and GND for applications that may require up to 100 mA of current operation and PF12 for triggering. PFI2 has the same functionality as described above, but it is overloaded on TRIG0 (SCANCLK) on the mini-DIN connector and is accessible only through the optional 9-pin mini-DIN to BNC female cable adapter.
Chapter 4 Hardware Overview The CH0, CH1, and TRIG channels have a software-programmable coupling selection between AC and DC. Use AC coupling when your AC signal contains a large DC component. Without AC coupling, it is difficult to view details of the AC component with a large DC offset and a small AC component, such as switching noise on a DC supply. If you enable AC coupling, you remove the large DC offset for the input amplifier and amplify only the AC component.
Chapter 4 Hardware Overview ADC Pipeline Delay The ADC on the NI 5102 is a pipelined flash converter with a maximum conversion rate of 20 MS/s. The pipelined architecture imposes a 2.5 Scan Clock cycle delay to convert analog voltage into a digital value, as shown in Figure 4-7. 1 2 3 4 5 6 Input Scan Clock 1 2 3 4 Figure 4-7.
Chapter 4 Hardware Overview Table 4-4. Possible Number of Samples for Posttriggered Scans Number of Channels NI 5102 (PCI, PXI) NI 5102 (ISA, PCMCIA, USB) Min Max Min Max One 1 16,777,088* 1 663,000 Two 1 16,777,088* 1 331,500 * Dependent on available memory If Scan Clock is externally supplied, you must supply a free-running clock for proper operation.
Chapter 4 Hardware Overview Table 4-5 describes the posttrigger acquisition signals. Table 4-5. Posttrigger Acquisition Signals Signal Description Start Trigger Triggers the acquisition. It can be generated through software, or CH0, CH1, TRIG, PFI1, and PFI2, or any of the seven RTSI bus trigger lines. RTSI bus trigger lines are available only on the NI 5102 (PCI, PXI, ISA). Scan Clock Causes the ADC to convert the input signal into digital data.
Chapter 4 Hardware Overview Pretrigger Acquisition In pretrigger acquisition mode, the device acquires a certain number of scans, called the pretrigger scan count, before the trigger occurs. After satisfying the pretrigger scan count requirement, hardware keeps acquiring data and stores it in a circular buffer implemented in onboard memory. The size of the circular buffer equals the pretrigger scan count.
Chapter 4 Hardware Overview Figure 4-9 shows the relevant timing signals for a typical pretriggered acquisition. The illustration represents five pretrigger and five posttrigger scans, and above-high-level analog triggering is used. See the Analog Trigger Circuit section later in this chapter for more information on analog trigger types.
Chapter 4 Hardware Overview Table 4-7 describes the pretrigger acquisition signals. Table 4-7. Pretrigger Acquisition Signals Signal Description Start Trigger Starts data acquisition. In pretrigger mode, the Start Trigger signal enables the storage of pretrigger data. Start Trigger can only be generated through software in pretrigger mode. Scan Clock Causes the ADC to convert the input signal into digital data. This signal is also used in the memory controller to write the data into onboard memory.
Chapter 4 Hardware Overview Trigger Sources The Scan Clock, Start Trigger, and Stop Trigger signals can be generated through software or supplied externally as digital triggers or as analog triggers on one of the input channels or the TRIG channel. Figure 4-10 shows the different trigger sources. In addition, Scan Clock is available from a source (counter) internal to the NI 5102.
Chapter 4 Hardware Overview Analog Trigger Circuit The NI 5102 contains a sophisticated analog trigger circuit that accepts boolean outputs from level comparators and makes intelligent decisions about the trigger. Several triggering modes are available, including edge, window, and hysteresis. For information on configuring trigger functions, see the Triggering Functions and Parameters section in Chapter 3, Common Functions and Examples, of your NI-SCOPE Software User Manual.
Chapter 4 Hardware Overview Start End of Acquisition Hold-off Hold-off Time in nanoseconds (Adjustable between 800 ns and 6.71 s) = Trigger Not Accepted = Trigger Accepted a. Posttriggered Acquisition with Hold-off Stop End of Acquisition Hold-off Acquisition in Progress Hold-off Time in nanoseconds (Adjustable between 800 ns and 6.71 s) b. Pretriggered Acquisition with Hold-off Figure 4-11.
Chapter 4 Hardware Overview Random Interleaved Sampling The NI 5102 supports Random Interleaved Sampling (RIS), a form of Equivalent Time Sampling (ETS) which allows multiplication of the maximum real-time sampling rate. The maximum interpolation factor on the NI 5102 is 50, resulting in a maximum effective sampling rate of 1 GS/s. At this rate, the ratio of logical bins to physical bins is approximately 1:9. The minimum RIS rate is 40 MS/s.
Chapter 4 Hardware Overview your NI 5102 and afterwards whenever operating environment conditions change. Externally recalibrate the NI 5102 when its interval has expired. This requires connecting a precision reference to your device, and is normally performed at NI or a metrology lab. See Appendix A, Specifications, for more information about calibration intervals, and your NI 5102 Calibration Procedure for detailed external calibration instructions.
Chapter 4 Analog Trigger Circuit Output RTSI In <0..6> Software PFI1, PFI2 Analog Trigger Circuit Output RTSI In <0..6> PFI1, PFI2 RTSI In <0..
Chapter 4 Hardware Overview PFI Lines All NI 5102 digitizers have two multipurpose programmable function digital input/output lines, PFI1 and PFI2, that you can use for external timing and triggering or outputting various signals. You can individually select the direction of these lines to be input or output. PFI Lines as Inputs PFI1 or PFI2 can be selected as inputs for the Start Trigger, Stop Trigger, and Scan Clock signals.
Chapter 4 Hardware Overview • Analog Trigger Circuit Output—This signal is the digital output of the Analog Trigger Circuit on the NI 5102. The frequency and duty cycle of this signal depends on the trigger channel, the trigger levels, polarity, and triggering mode. For more information, see the Analog Trigger Circuit section earlier in this chapter or your NI-SCOPE Software User Manual. • Frequency Output—This signal is a digital pulse train with programmable frequency.
Chapter 4 Hardware Overview Master/Slave Operation You can use two or more NI 5102 digitizers in one system to increase the number of channels for your application by synchronizing devices over the RTSI bus or PFI lines. Use the RTSI bus for synchronizing two or more NI 5102 (PCI, PXI, ISA) devices. For the NI 5102 (PCMCIA, USB), you must use the PFI lines.
Chapter 4 ♦ Hardware Overview 3. Program the master device to output its internal timebase on the RTSI bus clock line. 4. Program the master device to output its Scan Clock and Stop Trigger on unused RTSI bus trigger lines. 5. Program the slave device to use RTSI bus clock as its main timebase. 6. Program the slave device to use external Scan Clock and external Stop Trigger on RTSI bus trigger lines selected in step 4. 7. Arm the slave device for acquisition before arming the master device.
A Specifications This appendix lists the specifications of the NI 5102. These specifications are typical at 25 °C unless otherwise stated. The operating temperature range is 0 to 50 °C. Input Characteristics Number of input channels ...................... 2 single-ended, simultaneously sampled Input impedance..................................... 1 MΩ ±1% in parallel with 25 pF ±10 pF (Impedance increases with attenuating probes) CH0, CH1, TRIG ADC resolution ......................................
Appendix A Specifications Input signal ranges (CH0, CH1) (without probe attenuation) ....................±5 V at gain of 1 ±1 V at gain of 5 ±0.25 V at gain of 20 ±50 mV at gain of 100 Input coupling.........................................AC or DC, software-selectable Overvoltage protection ...........................±42 V (DC + peak AC < 10Khz without external attenuation) CH0, CH1, TRIG only Onboard FIFO memory depth ................663,000 samples Max waveform buffer .............................
Appendix A Specifications Transfer Characteristics Relative accuracy ................................... ±1 LSB typ, ±1.8 LSB max Differential nonlinearity......................... ±0.3 LSB typ, ±0.5 LSB max No missing codes ................................... 8 bits guaranteed Offset error after calibration .................. ±1.5 LSB max Gain error after calibration..................... ±1% max DC accuracy ........................................... ±2.
Appendix A Specifications Triggers Analog Source .....................................................CH0, CH1, TRIG Level .......................................................256 levels between ±Full-scale for CH0 and CH1; ±5 V for TRIG; software-selectable Slope .......................................................Positive or negative, Software-selectable Resolution ...............................................8 bits, 1 in 256 Hysteresis................................................
Appendix A Symbol Parameter Cin Input capacitance (nominal) IOS Output short circuit current* Conditions Min — — VO = GND VO = Vcc Specifications Max 10 pF –15 mA 40 mA –120 mA 210 mA * Only one output at a time; duration should not exceed 30 s. RTSI (NI 5102 for PCI, PXI, ISA Only) Trigger lines ........................................... 7 I/O (6 I/O on the PXI-5102) Clock lines.............................................. 1 Power Consumption NI 5102 (PCI) 5 V DC (±5%)................
Appendix A Specifications Maximum Working Voltage (Signal voltage plus common-mode voltage) Channel to earth......................................5 V, Installation Category I Channel to channel .................................5 V, Installation Category I Environmental Operating temperature ............................0 to 55 °C Storage temperature ................................–20 to 70 °C Relative humidity ...................................10% to 90% noncondensing Maximum Altitude ..................
Appendix A Specifications by your product, and a link to the DoC (in Adobe Acrobat format) appears. Click the Acrobat icon to download or read the DoC. Calibration Internal ................................................... Upon software command; adjusts timing for RIS acquisitions only Interval ............................................ 1 week, or anytime operating environment changes External .................................................. Internal reference recalibrated Interval ................
Technical Support Resources B Web Support NI Web support is your first stop for help in solving installation, configuration, and application problems and questions. Online problem-solving and diagnostic resources include frequently asked questions, knowledge bases, product-specific troubleshooting wizards, manuals, drivers, software updates, and more. Web support is available through the Technical Support section of ni.com. NI Developer Zone The NI Developer Zone at ni.
Appendix B Technical Support Resources Worldwide Support NI has offices located around the world to help address your support needs. You can access our branch office Web sites from the Worldwide Offices section of ni.com. Branch office Web sites provide up-to-date contact information, support phone numbers, e-mail addresses, and current events. If you have searched the technical support resources on our Web site and still cannot find the answers you need, contact your local office or NI corporate.
Glossary Prefix Meaning Value p- pico- 10–12 n- nano- 10–9 µ- micro- 10–6 m- milli- 10–3 k- kilo- 103 M- mega- 106 G- giga- 109 Numbers/Symbols ° degree – negative of, or minus Ω ohm / per % percent + positive of, or plus ± plus or minus +5 V +5 Volts signal A A amperes A/D analog-to-digital AC alternating current © National Instruments Corporation G-1 NI 5102 User Manual
Glossary AC coupled allowing the transmission of AC signals while blocking DC signals ADC analog-to-digital converter—an electronic device, often an integrated circuit, that converts an analog voltage to a digital number ADC resolution the resolution of the ADC, which is measured in bits.
Glossary bandwidth the range of frequencies present in a signal, or the range of frequencies to which a measuring device can respond bipolar a signal range that includes both positive and negative values (for example, –5 V to +5 V) BNC a type of coaxial signal connector buffer temporary storage for acquired or generated data burst-mode a high-speed data transfer in which the address of the data is sent followed by back-to-back data words while a physical signal is asserted bus the group of condu
Glossary channel pin or wire lead to which you apply or from which you read the analog or digital signal. Analog signals can be single-ended or differential. For digital signals, you group channels to form ports.
Glossary counter/timer a circuit that counts external pulses or clock pulses (timing) coupling the manner in which a signal is connected from one location to another Cp probe capacitance CPU central processing unit crosstalk an unwanted signal on one channel due to an input on a different channel current drive capability the amount of current a digital or analog output channel is capable of sourcing or sinking while still operating within voltage range specifications current sinking the abilit
Glossary DC coupled allowing the transmission of both AC and DC signals default setting a default parameter value recorded in the driver. In many cases, the default input of a control is a certain value (often 0) that means use the current default setting. For example, the default input for a parameter may be do not change current setting, and the default setting may be no AMUX-64T boards. If you do change the value of such a parameter, the new value becomes the new setting.
Glossary DOS disk operating system down counter performing frequency division on an internal signal DRAM dynamic RAM drivers software that controls a specific hardware device such as a DAQ device or a GPIB interface board DSO digital storage oscilloscope dual-access memory memory that can be sequentially accessed by more than one controller or processor but not simultaneously accessed.
Glossary expansion ROM an onboard EEPROM that may contain device-specific initialization and system boot functionality external trigger a voltage pulse from an external source that triggers an event such as A/D conversion F false triggering triggering that occurs at an unintended time FET field-effect transistor fetch-and-deposit a data transfer in which the data bytes are transferred from the source to the controller, and then from the controller to the target FIFO first-in first-out memory buf
Glossary G gain the factor by which a signal is amplified, sometimes expressed in decibels gain accuracy a measure of deviation of the gain of an amplifier from the ideal gain GND ground signal grounded measurement system see RSE H h hour half-flash ADC an ADC that determines its output code by digitally combining the results of two sequentially performed, lower-resolution flash conversions half-power bandwidth the frequency range over which a circuit maintains a level of at least –3 dB with r
Glossary input bias current the current that flows into the inputs of a circuit input impedance the measured resistance and capacitance between the input terminal of a circuit input offset current the difference in the input bias currents of the two inputs of an instrumentation amplifier instrument driver a set of high-level software functions that controls a specific GPIB, VXI, or RS-232 programmable instrument or a specific plug-in DAQ device.
Glossary K k kilo—the standard metric prefix for 1,000, or 103, used with units of measure such as volts, hertz, and meters K kilo—the prefix for 1,024, or 210, used with B in quantifying data or computer memory kbytes/s a unit for data transfer that means 1,000 or 103 bytes/s kS 1,000 samples Kword 1,024 words of memory L LabVIEW laboratory virtual instrument engineering workbench latched digital I/O a type of digital acquisition/generation where a device or module accepts or transfers data a
Glossary MFLOPS million floating-point operations per second—the unit for expressing the computational power of a processor MIPS million instructions per second—the unit for expressing the speed of processor machine code instructions MISO Master-In-Slave-Out signal MITE MXI Interfaces to Everything—a custom ASIC designed by National Instruments that implements the PCI bus interface.
Glossary NRSE nonreferenced single-ended mode—all measurements are made with respect to a common (NRSE) measurement system reference, but the voltage at this reference can vary with respect to the measurement system ground Nyquist Sampling Theorem a law of sampling theory stating that if a continuous bandwidth-limited signal contains no frequency components higher than half the frequency at which it is sampled, then the original signal can be recovered without distortion O onboard channels channels pr
Glossary PGIA programmable gain instrumentation amplifier pipeline a high-performance processor structure in which the completion of an instruction is broken into its elements so that several elements can be processed simultaneously from different instructions Plug and Play devices devices that do not require DIP switches or jumpers to configure resources on the devices—also called switchless devices Plug and Play ISA a specification prepared by Microsoft, Intel, and other PC-related companies that
Glossary R RAM random-access memory real time a property of an event or system in which data is processed as it is acquired instead of being accumulated and processed at a later time record length the amount of memory dedicated to storing digitized samples for postscripting or display.
Glossary Rp probe resistance RSE referenced single-ended mode—all measurements are made with respect to a common reference measurement system or a ground.
Glossary SC_TC scan counter terminal count signal SCXI Signal Conditioning eXtensions for Instrumentation—the NI product line for conditioning low-level signals within an external chassis near sensors so only high-level signals are sent to DAQ devices in the noisy PC environment SE single-ended—a term used to describe an analog input that is measured with respect to a common ground self-calibrating a property of a DAQ device that has an extremely stable onboard reference and calibrates its own A/D a
Glossary switchless device devices that do not require dip switches or jumpers to configure resources on the devices—also called Plug and Play devices synchronous (1) hardware—a property of an event that is synchronized to a reference clock (2) software—a property of a function that begins an operation and returns only when the operation is complete system noise a measure of the amount of noise seen by an analog circuit or an ADC when the analog inputs are grounded system RAM RAM installed on a pers
Glossary U unipolar a signal range that is always positive (for example, 0 to +10 V) update the output equivalent of a scan. One or more analog or digital output samples. Typically, the number of output samples in an update is equal to the number of channels in the output group.
Glossary W W watts waveform multiple voltage readings taken at a specific sampling rate word the standard number of bits that a processor or memory manipulates at one time.
Index A ADC pipeline delay, 4-8 analog trigger circuit, 4-15 CH0 and CH1 input ranges (table), 4-6 Scan Clock delay (figure), 4-8 trigger hold-off, 4-15 to 4-16 trigger sources, 4-14 Analog Trigger Circuit Output signal, 4-21 analog trigger specifications, A-4 AUX (serial communications port), 4-6 AUX signal (table), 4-5 AC/DC coupling change settling rates (table), 4-7 acquiring data, 1-2 to 1-5 interactive control of NI 5102 using Scope Soft Front Panel, 1-3 NI application software, 1-4 to 1-5 NI-DAQ AP
Index D F data acquisition. See acquiring data.
Index M PFI lines, 4-20 to 4-21 input lines, 4-20 output lines, 4-20 to 4-21 random interleaved sampling, 4-17 RTSI bus trigger and clock lines, 4-18 to 4-19 manual. See documentation.
Index timing signals (figure), 4-12 trigger hold-off (figure), 4-16 probes and waveform effect, 3-8 to 3-11 active and current probes, 3-11 compensating the probe, 3-9 to 3-11 passive probe, 3-8 to 3-11 PXI-compatible products NI 5102 J2 pin assignments (table), 1-6 using with standard CompactPCI, 1-5 to 1-6 NI-DAQ driver software overview of NI-DAQ API, 1-4 relationship with programming environment and hardware (figure), 1-3 NI Developer Zone, B-1 NI-SCOPE driver, 1-4 Nyquist theorem, 3-1 O optional equ
Index T Scope Soft Front Panel, 1-3 serial communications port (AUX), 4-6 signal connections, 4-5 to 4-6 I/O connector signal descriptions (table), 4-5 serial communications port (AUX), 4-6 signal shape, general, 3-7 Soft Front Panel, 1-3 software programming choices. See acquiring data.
