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NI-ELVIS Series IIThe major device that you will use in this lab is the NI ELVIS Series II workstation shown in Figure 1. The workstation consistsof a prototyping board and several other features that are essential for laboratory experiments conducted in the ECE department.These features are explained below in Table 1:Figure 1. Isometric View of NI ELVIS II workstation with Prototyping BoardTABLE I.Workstation PowerSwitchPrototyping BoardPower SwitchDigital Multimeter(DMM) ConnectorsWORKSTATION FEATURES– Located in the rear of the workstation– Powers the NI ELVIS II series– Controls power to NI ELVIS Series II prototyping board.– The power LED lights up when the switch is turned ON.– The Ready switch should be green or yellow whenconnected to host.– Voltage, Resistance, and Diode Banana Jack (red):The positive input for digital multimeter in voltageresistance and diode measurements.– Common Banana Jack (black): The common referenceconnection for digital multimeter voltage, current,resistance, and diode measurements.– Current Banana Jack (red): The positive input fordigital multimeter current measurements.

OscilloscopeConnectors andFunction GeneratorOutputs/DigitalTrigger InputVariable PowerSupply ManualControlsFunction GeneratorManual ControlNI ELVIS II SeriesPrototyping BoardOscilloscope (Scope) Connectors (Input)– CH 0 BNC Connector: The input for channel 0 of theoscilloscope.– CH 1 BNC Connector: The input for channel 1 of theoscilloscope.FGEN/Trigger ConnectorOptional output of the function generator or a digitaltrigger input.This allows you to adjust the voltage for two variablepower supplies.– Supply which can supply between 0 and 12V– Supply– can which supply between 0 and -12V– Knobs active only when the associated power supply isin manual mode.– LED lights up next to each knob lights up whenassociated power supply is in manual mode.These knobs allow the user to manually adjust thefrequency and amplitude for a function generator outputwaveform. The Manual Mode LED lights up when thefunction generator is in manual mode.Instructions on how to use the function generator to input awaveform and to adjust its frequency and amplitude areexplained later.Provides an area for building circuitry and has necessaryconnections to access signals for common applications

I.PROTOTYPING BOARD FEATURESThe prototyping board has several features on interest that are labeled in Figure 2. Each signal in features 2, 3, 6 and 8 has a rowof five pin sockets all tied together.Figure 2. NI ELVIS II Series Prototyping BoardTABLE II.BreadboardAnalog Input (AI) andProgrammable FunctionsInterface (PFI) signal rowsSIGNAL DESCRIPTIONS ON NI ELVIS II PROTOTYPING BOARD.– This is the work area on which most circuits are built.– Figure 3 shows how the terminals are internallyconnected.– The horizontal connections labeled “ ” and “-” andcolored red and blue are called buses and are typicallyused for power and ground signals.– The vertical contacts are used for the actual building ofcircuitsAnalog InputsThere are 8 analog input channels labeled AI 0 7 .Connect positive end of the signal to be measured tothe positive “ ” pin socket and the negative end of thesignal to the negative “-” pin socket of the inputchannel. These channels are mostly used as inputs forthe oscilloscope discussed later.Programmable Functions I/O– These lines labeled 0 2 , 5 7 and 10 11 are used for static digital input output or timingsignals.AI SENSE and AI GND (INPUT)– These pin sockets are used in cases where the signal tobe measured has a different ground potential from theworkstation.

DigitalMultimeter(DMM)/Impedance AnalyzerAnalog Output (AO)User ConfigurableInput/OutputFunction Generator(FGEN)Power SuppliesDMM/Impedance Analyzer (INPUT)– BASE: excitation terminal used as base terminal in 3wire voltage/current analyzer of a bipolar junctiontransistor discussed later.– DUT : excitation for capacitance and tage/current analyzer and collector terminal for abipolar junction transistor for 3-wire voltage/currentanalyzer. All of which are discussed later.– DUT-: virtual ground for capacitance and tage/current analyzer and emitter terminal for abipolar junction transistor for 3-wire voltage/currentanalyzer.Analog OutputsThere are 2 analog output channels labeledAO 0 1 . These channels are used as outputs forthe arbitrary waveform generator discussed later.User Configurable I/O– BANANA A D : Connects to the banana jacks AD (see feature 4).– BNC 1 2 : Positive lines connect to center pins ofthe BNC connectors (see feature 4). Negative linesconnect to shells of the BNC connectors.– SCREW TERMINAL 1 2 : connects to the screwterminals (see feature 4).Function Generator– FGEN (Output): the output of the function generator– SYNC (Output): 5V TTL signal synchronized to theFGEN signal. This signal is most used as a triggersignal for the oscilloscope (see feature 4 in Table 1).– AM (Input): Analog input used to modulate theamplitude of the FGEN signal.– FM (Input): Analog input used to modulate thefrequency of FGEN signal.Variable Power Supplies (OUTPUT)– SUPPLY : Positive variable power supply output (seefeature 5 in Table 1). Can supply between 0 and 12V.– GROUND: Ground (all signals referenced to ground).– SUPPLY-: Negative variable power supply output(see feature 5 in Table 1). Can supply between 0 and 12V.DC Power Supplies (OUTPUT)– 15V fixed power supply.

User-Configurable ScrewTerminals, BNCconnectors and Bananajack connectorsDC power supplyindicators–––-15V fixed power supply.GROUND: Ground. 5V fixed power supply–Banana A D Jacks: connected to BANANA A D signal rows (see feature 3).BNC 1 2 Connectors: connected to BNC 1 2 signal rows (see feature 3).SCREW TERMINAL 1 2 : connects to thescrew terminal signal rows (see feature 3).––– 15V and 5V power supply indicators: Theseindicators should be lit to when the prototyping boardpower is enabled.– If these indicators are not lit, then there is a possibleshort circuit. Turn off prototyping board and checkconnections.– Turning the board power switch on and off should resetthe current limiters.

Digital input/output signalrowsDIO 0 23 (INPUT/OUTPUT)Digital I/O lines that are used to read or write digital data(0 or 5V). These lines are programmed to be inputs oroutputs using soft front panels (SFPs) discussed later.User-Configurable LEDsUser-Configurable LEDs (OUTPUT)These LEDs act as displays for digital outputs (i.e. 0 or5V). See feature 8 for further DC Power SupplyCounter/Timer (INPUT/OUTPUT)– PFI8/CTRO SOURCE: Counter 0 Source– PFI9/CTRO GATE: Counter 0 Gate– PFI12/CTRO OUT: Counter 0 Out– PFI3/CTR1 SOURCE: Counter 1 Source– PFI4/CTR1 GATE: Counter 1 Gate– PFI13/CTR1 OUT: Counter 1 Out– PFI14/FREQ OUT: Frequency OutLED 0 7 (INPUT)– Input pin sockets for user-configurable LEDs (seefeature 7).DSUB SHIELD (INPUT/OUTPUT)– Connects to shield of DSUB connector (see feature 9).DSUB PIN 1 9 (INPUT/OUTPUT)– Connects to pins 1 9 of DSUB connector (seefeature 9).DC Power Supply (OUTPUT)– Ground– 5V fixed power supply

DSUB Connector (I/O)Connected to DSUB PIN 1 9 and DSUB SHIELDsignal rows (see feature 8).User-Configurable DSUBconnectorEach of these five set of contacts are tied togetherAll pins on each of these columns are connected together.So the user can use “ ” for DC power supply and “-” for groundFigure 3. Breadboard connectionsII.NI ELVIS II DEVICESThis chapter provides an overview of the devices present in the NI ELVIS II Series workstation. These devices can becontrolled by software to include soft front panel (SFP) instruments, LabVIEW Express VIs, and SignalExpress blocks. For thepurposes of the ECE department, the use of NI ELVIS II Series with SFP instruments will be discussed exclusively. A NIELVISmx SFP, as the name implies, is the software version of the front panel of an NI ELVIS device.A. NI ELVISmx Instrument Launcher:The NI ELNIS Instrument Launcher provides access to the NI ELVISmx SFP instruments. Launch the Instrument Launcher bynavigating to Start All Program Files National Instruments NI ELVISmx NI ELVISmx Instrument Launcher. Thisopens the GUI shown in Figure 4. To launch an instrument, click the button corresponding to the desired instrument. Beforeopening a SFP, the workstation should be powered with the USB READY light lit, otherwise an error occurs. If said error occurs,close SFP, power on the workstation, check connection to host PC, and open SFP again.Figure 4.NI ELVISmx Instrument Launcher

B. DMM (Digital Multimeter)This commonly used instrument is used to measure voltage (DC and AC), current (DC and AC), resistance, capacitance,inductance. Additionally it used for diode tests and audible continuity tests. The DMM SFP is shown in Figure 5.The top row of nine buttons denotes the different DMM modes, namely from left to right: DC voltage measurement, AC voltagemeasurement, DC current measurement, AC current measurement, resistance measurement, capacitance measurement, inductancemeasurement, diode continuity and audible continuity. An explanation of the labeled controls is as follows.1.Display: This is when the current measurement is displayed. The “%FS” bar shows the percentage of the current range thatis being used. The higher the percentage, the more accurate the result (see 8 for more details).2.Modes: These rows of buttons are used to the select the operation the user would like the digital multimeter to perform.3.Connections: shows where to connect the signal or device to be measured.4.Acquisition mode: This selection determines whether the user wants the digital multimeter to keep measuring indefinitely(continuously) or just taking one measurement and stop.5.Help: The button brings up the contest help and the online help for the soft front panel instrument.6.Run/Stop: These buttons are used to start data acquisition (Run) and to stop data acquisition (Stop).7.Null offset: This is an important control of the SFP. Say the user is taking small magnitude measurements and the “null”value (value with nothing connected) is substantial enough to affect the data readings. By clicking the null offset button at“null”, all subsequent measurements are made relative to the measurement when the button was pressed, which willimprove the accuracy of the measurements. It is not advisable to offset null for AC voltage measurements.8.Mode: Selects between “Auto” and “Manual” ranging of the instrument. It is recommended to use the “Auto” ranging(default). If “Manual” is selected, then the Range menu is enabled and different ranges can be selected.Figure 5. DMM SFP with important controls labeled1) DC and AC voltage measurementsThese modes are selected when user requires measurements of time invariant (DC) voltage and time varying (AC) currentrespectively. The measurements are made in terms of DC Voltage (VDC) and RMS Voltage (VAC) respectively. The signalconnections for both modes are the same. The positive end is connected to the red voltage, resistance, and diode banana jack shownin feature 3 in Table 1. The negative end is connected to the black common banana jack (COM) also shown in feature 3 in Table 1.2) DC and AC current measurementsThese modes are selected when user requires measurements of time invariant current and time varying current respectively. Themeasurements are made in terms of DC amperes (IDC) and Ampere RMS (IAC) respectively. The signal connections for both

modes are the same. The positive end is connected to the red current banana jack (A) shown in feature 3 in Table 1. The negativeend is connected to the black common banana jack (COM) also shown in feature 3 in Table 1.3) Resistance MeasurementThis mode is used when user requires the resistance of a device under test. The measurements are made in terms of ohms (Ω).The device connections are the same as that of the DC and AC voltage measurements.4) Capacitance and Inducatnace MeasurementThis mode is selected when user requires the capacitance and inductance of a device respectively. The measurements are madein terms of Farads (F) and Henry (H) respectively. The positive end of the device under test should be connected to the pin “DUT ”on the prototyping board, shown in feature 3 in Table 2. The negative end of the device under test should be connected to the pin“DUT-” on the prototyping board, also shown in feature 3 in Table 2.5) DiodeThis mode is selected when the user wants to determine the terminals of a diode (i.e. whether the device is forward-biased orreverse-biased). The multimeter indicates when the device under test is open or closed. The device connections are the same as thatof the DC and AC voltage measurement.6) ContinuityThis mode is selected when the user wishes to determine if two nodes (or pin sockets) are at the same potential (or tiedtogether). If said nodes are connected together, an audible cue is given and additionally the display shows “Closed”. Otherwisethere is no audible cue and the display shows “Open”.C. Scope (Oscilloscope)The oscilloscope is a device that displays signal voltages as a two-dimensional graph of electrical potential differences (verticalaxis) plotted as a function of time (horizontal axis). Though time-invariant (DC) voltages can be displayed, this device is commonlyused to display time-varying voltage signals. The NI ELVISmx Oscilloscope consists of two channels, Channel 0 and Channel 1,which can automatically connect to up to ten (10) sources. Shown below is the Scope SFP in Figure 6, as well as an explanation ofthe important controls.1.Scope Graph: displays the waveforms specified in Channel 0 and Channel 1 as well as the cursors (see 9). The bottom ofthe scope graph displays various signal characteristics (“CH 0 Meas.” and “CH1 Meas.”). These characteristics include rootmean square (RMS), frequency (Freq) and the peak to peak amplitude (Vp-p). These measurements are only shown if thechannel is enabled (see parts 2 and 8).2.Channel Settings: as previously stated there are two oscilloscope channels Channel 0 and Channel 1. Channel settingsallow the user to specify the source signal that will be displayed for each channel. The choices include SCOPE CH 0 andSCOPE CH 1 BNC input channels (see feature 4 in Table 1) or AI 0 7 input signal rows (see feature 2 in Table 2). TheEnabled box below the channel settings allow the user to specify which channels to display in the scope graph.3.Probe and Coupling: The probe setting is dependent on what kind of probe is being used to measure the signal voltage. Thetwo available settings are “1 ” and “10 ”. Unless specified, use the “1 ” setting. In some case the signal being measured isthe sum of a time-varying voltage and a DC signal. If the user chooses to display only the AC part of the signal then thecoupling setting can be changed to “AC”. This setting will display only the AC part of the signal. The “AC” setting is notavailable for signals measured with the AI channels (See part 4).4.Volts/Div (Vertical sensitivity) and Vertical Position: The Volts/Div knob or drop-down menu allows the user to choose they-axis (voltage axis) scale. The Vertical Position knob or numerical input allows the user to adjust the zero cross (or Y axispositioning of the displayed waveform). The user is most likely to use this control when the waveform is the sum of timevarying signal and a DC signal (see part 3).5.Trigger: This oscilloscope features triggered sweeps. A triggered sweep starts (begins data acquisition) at a selected pointon a trigger signal, providing a stable display. The scope has three settings: Immediate, in which there is no external triggersignal and the data acquisition begins immediately; Digital, in which acquisition begins on the rising edge or fall edge(Slope setting) of an external digital signal; Edge, in which data acquisition begins when an internal or external signalcrosses a specified threshold (Level (V) setting). For the Digital setting, the trigger signal source is the TRIG BNC inputchannel (see feature 4 in Table 1). For the Edge setting, the choices of signal sources are the Chan 0, Chan 1 or the TRIGBNC input channel.6.Log: allows the user to take a snapshot of the waveform(s) displayed on the scope graph and save the waveform as a .csvfile which allows for the plotting of displayed waveforms in other programs such as Matlab and Excel.7.Timebase (Horizontal sensitivity): The Time/Div control knob and menu allows the user to choose the time-axis scale.

8.Display Measurements: Allows the user to select which channel measurements to display at the bottom of the scope graph(see part 1).9.Cursor Settings: allows the user to display up to two cursors on the scope graph. The cursor position is then displayed at thebottom of the scope graph. The cursors can be moved horizontally by clicking the cursor and dragging it along the timeaxis. The user can also select which of the two channels, Chan 0 and Chan 1, are associated with the two cursors.Figure 6. DMM SFP with important controls labeledD. FGEN (Function Generator)The function generator is a device that generates time varying waveforms. The NI ELVISmx Function generator is generallyused to generate a periodic voltage signal in the form of a sine wave, a triangular wave or a square wave. The function generatoroutput can be obtained via two routes: the FGEN BNC output channel (see feature 4 in Table 1) or the FGEN prototyping board pinsockets (see feature 3 in Table 2). Shown below is the FGEN SFP in Figure 7, as well as an explanation of the important controls.The FGEN signal is referenced with respect to GROUND.Figure 7. FGEN SFP with important controls labeled

1.Frequency Display: displays the frequency of the output waveform. When the function generator is off, “OFF” is displayed.2.Waveform Selectors: allows the user to select what type of waveform is generated. The choices are sine wave, triangularwave and square wave.3.Waveform characteristics: the characteristics of the output waveform can be selected by the user. These characteristicsinclude: Frequency, peak-to-peak amplitude, DC offset, duty cycle that is only enabled when square wave is selected as thewaveform type, and adjusts the turn-on to turn-off ratio of the wave, and the modulation type which controls the type ofmodulation (Amplitude or Frequency with the corresponding inputs shown in feature 3 in Table 2). Note that the timevarying component of the output waveform is symmetrical with a peak amplitude of one-half the peak-to-peakamplitude.4.Sweep Settings: The NI ELVIS II function generator has the capability to modulate the frequency automatically, based onuser specified Sweep Settings. The sweep setting controls include: Start Frequency which specifies the starting frequencyfor the frequency sweep; Stop Frequency which specifies the frequency at which the frequency sweep stops; Step whichspecifies the frequency interval between each frequency iteration during a frequency sweep; and Step Interval whichspecifies the time interval for each frequency iteration (see part 7).5.Manual Mode: The NI ELVIS II function generator allows the user to manually adjust the output waveform frequency andamplitude (see feature 6 in Table 1). This mode should be used when a high accuracy of a time varying signal is desired orif an undesired DC offset is observed when in automatic mode, even though the DC offset is set to zero.6.Signal Route. Allows the user to select where to route the generated signal. The choices are the FGEN BNC output channel(see feature 4 in Table 1) or the FGEN prototyping board pin sockets (see feature 3 in Table 2).7.Sweep: allows the user to enable a frequency sweep (see part 4).E. VPS (Variable Power Supply)The variable power supply consists of two channels that supply adjustable output voltages from 0 to