IBM Car Amplifier 7220 Manuel d'utilisateur

Model 7220DSP Lock-in AmplifierInstruction Manual190171-A-MNL-CCopyright © 1996 EG&G INSTRUMENTS CORPORATION

1-2Chapter 1, INTRODUCTIONAppendix DShows the connection diagrams for suitable RS232 null-modem cables to couple theunit to an IBM-PC or 100 % compati

6-24Chapter 6, COMPUTER OPERATIONand HC commands. It also interacts with the LEN command and affects the valuesreported by the M command.LEN [n] Curve

6-25Chapter 6, COMPUTER OPERATIONHC Halt curve acquisitionHalts curve acquisition in progress. It is effective during both single (data acquisitionini

6-26Chapter 6, COMPUTER OPERATIONThe computer program’s subroutine which reads the responses to the DC commandneeds to run a FOR...NEXT loop of length

6-27Chapter 6, COMPUTER OPERATION<X output value1><delim><Magnitude value1><term><X output value2><delim><Magni

6-28Chapter 6, COMPUTER OPERATIONbit number bit negated bit asserted0 data + parity = 8 bits data + parity = 9 bits1 no parity bit 1 parity bit2 even

6-29Chapter 6, COMPUTER OPERATIONbyte is accessed by performing a serial poll.Bit 0 Command completeBit 1 Invalid commandBit 2 Command parameter error

6-30Chapter 6, COMPUTER OPERATION6.4.12 Front PanelLTS [n] Lights on/off controlThe value of n controls the front panel LEDs and LCD backlights accord

6-31Chapter 6, COMPUTER OPERATIONThe controlling program would send a new output command each time a new readingwere required. Note that a good “rule

6-32Chapter 6, COMPUTER OPERATION6.5.04 X and Y Output Curve Storage MeasurementIn this example, the lock-in amplifier is measuring a current input si

6-33Chapter 6, COMPUTER OPERATIONNC Clear and reset curve bufferLEN 20000 500 ms recording time at 40 kHz = 20,000 pointsTADC 6 Set ADC1 sampling to b

1-3Chapter 1, INTRODUCTION1.3 Key Specifications and BenefitsThe EG&G Instruments Model 7220 represents the latest in DSP Lock-in Amplifiertechnol

6-34Chapter 6, COMPUTER OPERATIONNC Clear and reset curve bufferCBD 49180 Stores Magnitude, Phase, Sensitivity and Frequency(i.e. bits 2, 3, 4, 14 and

SpecificationsAppendix AA-1Measurement ModesX In-phase Y Quadrature  The unit can simultaneously present anyR Magnitude  two of these as outputsθ P

A-2Appendix A, SPECIFICATIONSCurrent InputMode Low Noise or Wide BandwidthFull-scale SensitivityLow Noise 20 fA to 10 nA in a 1-2-5 sequenceWide Bandw

A-3Appendix A, SPECIFICATIONSOrthogonality 90º ±0.0001ºDrift < 0.01º/ºC below 10 kHz< 0.1º/ºC above 10 kHzAcquisition TimeInternal Reference ins

A-4Appendix A, SPECIFICATIONSAmplitudeRange 1 mV to 5 VSetting Resolution1 mV to 500 mV 1 mV501 mV to 2 V 4 mV2.001 V to 5 V 10 mVAccuracy0.001 Hz to

A-5Appendix A, SPECIFICATIONSSignal MonitorAmplitude ±10 V FSImpedance 1 kΩAux D/A Output 1, 2Maximum Output ±10 VResolution 1 mVAccuracy ±0.1 %Output

A-6Appendix A, SPECIFICATIONSGeneralDimensionsWidth 432 mm (17 ")Depth 415 mm (16.4 ")HeightWith feet 74 mm (2.9 ")Without feet 60 mm (

PinoutsAppendix BB-1B.1 RS232 Connector Pinout123467859Figure B-1, RS232 and AUX RS232 Connector (Female)PIN FUNCTION COMMENT2 RXD Data In3 TXD Data O

B-2Appendix B, PINOUTSB.3 Digital Output Port ConnectorFigure B-3, Digital Output Port Connector8-bit TTL-compatible output set from the front panel o

DemonstrationProgramsAppendix CC-1C.1 Simple Terminal EmulatorThis is a short terminal emulator with minimal facilities, which will run on a PC-compat

1-4Chapter 1, INTRODUCTION

C-2Appendix C, DEMONSTRATION PROGRAMS100 B$=B$+CR$ ' append a carriage return110 GOSUB 180 ' output the command B$120 GOSUB 310: PRINT Z$; &

C-3Appendix C, DEMONSTRATION PROGRAMSC.3 GPIB User Interface ProgramGPCOM.BAS is a user interface program which illustrates the principles of the use

C-4Appendix C, DEMONSTRATION PROGRAMS290 V%=11: CALL IBTMO(DEV%,V%)300 '...set status print flag...310 INPUT "Display

Cable DiagramsAppendix DD-1D.1 RS232 Cable DiagramsUsers who choose to use the RS232 interface to connect the model 7220 lock-inamplifier to a standar

D-2Appendix D, CABLE DIAGRAMSFigure D-2, Interconnecting RS232 Cable Wiring Diagram

Alphabetical Listing ofCommandsAppendix EE-1ACGAIN [n] AC Gain controlSets the gain of the signal channel amplifier. Values of n from 0 to 9 can be en

E-2Appendix E, ALPHABETICAL LISTING OF COMMANDSAXO Auto-OffsetThe X and Y output offsets are turned on and set to levels giving zero X and Youtputs. A

E-3Appendix E, ALPHABETICAL LISTING OF COMMANDSBit Decimal value Output and range0 1 X Output (±10000 FS)1 2 Y Output (±10000 FS)2 4 Magnitude Output

E-4Appendix E, ALPHABETICAL LISTING OF COMMANDSCH n1 [n2] Analog output controlDefines what outputs appear on the rear panel CH1 and CH2 connectors ac

E-5Appendix E, ALPHABETICAL LISTING OF COMMANDSThe computer program’s subroutine which reads the responses to the DC commandneeds to run a FOR...NEXT

Installation &Initial ChecksChapter 22-12.1 Installation2.1.01 IntroductionInstallation of the model 7220 in the laboratory or on the production l

E-6Appendix E, ALPHABETICAL LISTING OF COMMANDS<X output value1><delim><Magnitude value1><term><X output value2><deli

E-7Appendix E, ALPHABETICAL LISTING OF COMMANDSEX [n] Output expansion controlExpands X and/or Y outputs by a factor of 10. Changes meter, CH1 and CH2

E-8Appendix E, ALPHABETICAL LISTING OF COMMANDSFSTART[.] [n] Oscillator frequency sweep start frequencySets the start frequency for a subsequent swee

E-9Appendix E, ALPHABETICAL LISTING OF COMMANDSHC Halt curve acquisitionHalts curve acquisition in progress. It is effective during both single (data

E-10Appendix E, ALPHABETICAL LISTING OF COMMANDSLF [n] Signal channel line frequency rejection filter controlIn instruments manufactured prior to June

E-11Appendix E, ALPHABETICAL LISTING OF COMMANDSLTS [n] Lights on/off controlThe value of n controls the front panel LEDs and LCD backlights according

E-12Appendix E, ALPHABETICAL LISTING OF COMMANDS\N n Address commandWhen the 7220 is daisy-chained with other compatible instruments this command will

E-13Appendix E, ALPHABETICAL LISTING OF COMMANDSOA[.] [n] Oscillator amplitude controlIn fixed point mode n sets the oscillator amplitude in mV. The r

E-14Appendix E, ALPHABETICAL LISTING OF COMMANDSRS [n1 [n2]] Set/read RS232 interface parametersThe values of n1 set the baud rate of the RS232 interf

E-15Appendix E, ALPHABETICAL LISTING OF COMMANDSSEN[.] [n] Full-scale sensitivity controlThe value of n sets the full-scale sensitivity according to t

2-2Chapter 2, INSTALLATION AND INITIAL CHECKSInstruments are normally shipped from the factory with the line voltage selector set to110-130 V AC, unle

E-16Appendix E, ALPHABETICAL LISTING OF COMMANDSST Report status byteCauses the lock-in amplifier to respond with the status byte.Note: this command i

E-17Appendix E, ALPHABETICAL LISTING OF COMMANDSreturn or carriage return-line feed terminator to the * command, since thesecharacters will slow down

E-18Appendix E, ALPHABETICAL LISTING OF COMMANDSSYNCOSC [n] Synchronous oscillator (demodulator monitor) controlThis control operates only in external

E-19Appendix E, ALPHABETICAL LISTING OF COMMANDSThe maximum sampling rate depends on the number of ADC inputs used and whetherthe sampling is timed or

E-20Appendix E, ALPHABETICAL LISTING OF COMMANDSTDC Take data continuouslyInitiates data acquisition. Acquisition starts at the current position in th

E-21Appendix E, ALPHABETICAL LISTING OF COMMANDSYOF [n1 [n2]] Y output offset controlThe value of n1 sets the status of the Y offset facility accordin

E-22Appendix E, ALPHABETICAL LISTING OF COMMANDS

Default SettingsAppendix FF-1Default Setting FunctionThe default setting function sets the model 7220’s controls and output displays asfollows:-Left-h

F-2Appendix F, DEFAULT SETTINGSLine frequency rejection filter OffAC Gain control ManualTime constant mode SyncADC trigger rate 200 HzFront panel ligh

IndexIndexIndex-1* command 6-18, E-16\N n command 6-28, E-122F reference mode 3-7, 5-48-bit programmable output port 3-890° Key 4-5Absolute accur

2-3Chapter 2, INSTALLATION AND INITIAL CHECKSinstalled, close the plastic door firmly. The correct selected voltage setting should nowbe showing throu

Index-2INDEXComputer control, sample programs 6-30Contrast control 5-10Control options menu 5-8Control setup menu 5-17CP [n] command 6-11, E-4Cur

Index-3INDEXInputconnector ground/float 5-3connector selection 5-2connector shell ground/float 3-2coupling 3-2, 5-3device selection 3-2, 5-3float

Index-4INDEXRatio display 5-32RATIO output 5-7Rear panel layout 4-6REF IN connector 3-10, 4-2, 5-4REF MON connector 4-7REF TTL connector 4-7, 5-

Index-5INDEXUpdate program 3-8Vector magnitude 3-8Ventilation 2-1VER command 6-29, E-20VMODE [n] command 6-10, E-20Voltage input mode 3-2What is

Index-6INDEX

WARRANTYEG&G Instruments Corporation warrants each instrument of its own manufacture to be free of defects in material andworkmanship for a period

2-4Chapter 2, INSTALLATION AND INITIAL CHECKSthe CONTROL SETUP menu is displayed, which will look similar to thefollowing:-Figure 2-3, Control Setup M

Technical DescriptionChapter 33-13.1 IntroductionThe model 7220 lock-in amplifier is capable of outstandingly good signal recoveryperformance, provide

3-2Chapter 3, TECHNICAL DESCRIPTION3.2.02 Signal-Channel InputsThe signal input amplifier may be configured for either single-ended or differentialvol

3-3Chapter 3, TECHNICAL DESCRIPTIONThe primary purpose of the DC coupling facility is to enable the use of the instrumentat reference frequencies belo

FCC NoticeThis equipment generates, uses, and can radiate radio-frequency energy and, if notinstalled and used in accordance with this manual, may cau

3-4Chapter 3, TECHNICAL DESCRIPTION3.2.04 AC GainThe signal channel contains a number of analog filters and amplifiers, the gain ofwhich are defined b

3-5Chapter 3, TECHNICAL DESCRIPTIONThis alias signal is indistinguishable from the output generated when a genuine signalat frequency falias is sample

3-6Chapter 3, TECHNICAL DESCRIPTIONThere is one situation where this automatic correction might not be sufficient to givegood performance. Consider th

3-7Chapter 3, TECHNICAL DESCRIPTION3.2.08 Internal OscillatorThe model 7220, in common with many other lock-in amplifiers, incorporates aninternal osc

3-8Chapter 3, TECHNICAL DESCRIPTIONand Y channel output filters. The outputs of these in turn drive two 16-bit digital toanalog converters (DACs) whic

3-9Chapter 3, TECHNICAL DESCRIPTION3.3.02 Relative AccuracyThe majority of lock-in amplifier measurements are concerned with the variation ofthe input

3-10Chapter 3, TECHNICAL DESCRIPTIONreserve is often expressed in decibels, for whichDR( in dB) = 20 log(DR( as a ratio))Applying this formula to the

3-11Chapter 3, TECHNICAL DESCRIPTIONThe circuits connected to the REF IN socket actually detect a positive-going crossingof the mean value of the appl

3-12Chapter 3, TECHNICAL DESCRIPTIONThe 6 dB/octave filters are not satisfactory for most purposes because they do notgive good rejection of periodic

3-13Chapter 3, TECHNICAL DESCRIPTIONwith respect to the reference input) and is computed by the output processor in thelock-in amplifier and made avai

Table of ContentsiTable of ContentsChapter One, Introduction1.1 How to Use This Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3-14Chapter 3, TECHNICAL DESCRIPTION3.10 Noise MeasurementsThe noise measurement facility is available only in the baseband mode (i.e. atreference fre

3-15Chapter 3, TECHNICAL DESCRIPTION3.12.02 Auto-SensitivityThis function only operates when the reference frequency is above 1 Hz. A singleAuto-Sensi

3-16Chapter 3, TECHNICAL DESCRIPTION3.12.05 Auto-MeasureThis function only operates when the reference frequency is greater than 1 Hz. Itperforms the

Front and Rear PanelsChapter 44-14.1 Front PanelFigure 4-1, Model 7220 Front Panel LayoutAs shown in figure 4-1 there are four BNC connectors with ass

4-2Chapter 4, FRONT AND REAR PANELS4.1.03 REF IN ConnectorThis is the input connector for a general purpose external reference signal. Whenexternal re

4-3Chapter 4, FRONT AND REAR PANELSprecision. In these cases a significant number of keypresses are required to makeadjustments.Adjustment of the latt

4-4Chapter 4, FRONT AND REAR PANELSFigure 4-6, Active Cursor OperationThe double keypress action can also be performed with one finger by firmly press

4-5Chapter 4, FRONT AND REAR PANELSFigure 4-8, Setup Menu Mode - Left and Right-hand LCD DisplaysIn the setup menu mode, the left-hand SELECT keys adj

4-6Chapter 4, FRONT AND REAR PANELSkeypress” feature. To perform such a switch, simply press both sides of the SELECTkeys simultaneously. This feature

4-7Chapter 4, FRONT AND REAR PANELS4.2.03 RS232 ConnectorThis 9-pin D type RS232 interface connector implements pins 1, 2, 3 and 7 (EarthGround, Trans

iiTABLE OF CONTENTS3.3.02 Relative Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4-8Chapter 4, FRONT AND REAR PANELS4.2.11 CH1, CH2 ConnectorsThe signal at these connectors is an analog voltage corresponding to a selectedoutput, su

Front Panel OperationChapter 55-15.1 IntroductionThis chapter describes how to operate the model 7220 using the front panel controls,and describes its

5-2Chapter 5, FRONT PANEL OPERATIONthe right-hand display. The setup menu description is shown on the left-hand side ofthe left-hand display. Figure 5

5-3Chapter 5, FRONT PANEL OPERATIONthe front panel BNC connector marked “B/I”, and uses a low-noise (LN) currentto voltage converter.InputThis control

5-4Chapter 5, FRONT PANEL OPERATION5.2.02 Reference Setup MenuFigure 5-3, Reference Setup MenuIn this menu, shown in figure 5-3, there are three contr

5-5Chapter 5, FRONT PANEL OPERATIONONWhen the Demodulator Monitor is switched ON and the instrument is operatingin External Reference mode, the signal

5-6Chapter 5, FRONT PANEL OPERATIONOFFOutput expansion is turned off.X ONLYA ×10 output expansion is applied to the X output only.Y ONLYA ×10 output e

5-7Chapter 5, FRONT PANEL OPERATIONMAG %fs CH1/2 Voltage+120 12.0 V+100 10.0 V0 0.0 V-100 -10.0 V-120 -12.0 VPHASE1When set to PHASE1 the correspondin

5-8Chapter 5, FRONT PANEL OPERATION5.2.04 Control Options MenuFigure 5-5, Control Options Setup MenuThis menu, shown in figure 5-5, has three controls

5-9Chapter 5, FRONT PANEL OPERATIONMANUALIn this setting the AC Gain may be manually adjusted from the main display.AUTOMATICIn this setting the AC Ga

iiiTABLE OF CONTENTS4.2.07 PREAMP POWER Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-10Chapter 5, FRONT PANEL OPERATION5.2.05 Miscellaneous Options MenuFigure 5-6, Miscellaneous Options Setup MenuThis menu, shown in figure 5-6, has t

5-11Chapter 5, FRONT PANEL OPERATION5.2.06 RS232 Setup 1 MenuFigure 5-7, RS232 Setup 1 MenuThis menu, shown in figure 5-7, has three controls affectin

5-12Chapter 5, FRONT PANEL OPERATION5.2.07 RS232 Setup 2 MenuFigure 5-8, RS232 Setup 2 MenuThis menu, shown in figure 5-8, has three controls affectin

5-13Chapter 5, FRONT PANEL OPERATIONMP command (report Magnitude and Phase). Hence it is necessary for the controllingprogram to be able to determine

5-14Chapter 5, FRONT PANEL OPERATION5.2.09 GPIB Setup 1 MenuFigure 5-10, GPIB Setup 1 MenuThis menu, shown in figure 5-10, has two controls affecting

5-15Chapter 5, FRONT PANEL OPERATION5.2.10 GPIB Setup 2 MenuFigure 5-11, GPIB Setup 2 MenuThis menu, shown in figure 5-11, has two controls affecting

5-16Chapter 5, FRONT PANEL OPERATION5.2.11 Digital Outputs Setup MenuFigure 5-12, Digital Outputs Setup MenuThis menu, shown in figure 5-12, is used t

5-17Chapter 5, FRONT PANEL OPERATION5.2.12 Control Setup MenuFigure 5-13, Control Setup MenuThe final setup menu, shown in figure 5-13, is used to set

5-18Chapter 5, FRONT PANEL OPERATION5.3 Auto Functions MenuWhen in the Main Display mode, one press of the MENU key accesses the AUTOMENU showing four

5-19Chapter 5, FRONT PANEL OPERATIONare steady, implying the signal phase is stable, when the procedure is called.If a zero error is present on the ou

ivTABLE OF CONTENTS6.3 RS232 and GPIB Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-20Chapter 5, FRONT PANEL OPERATIONThe line filter is disabled; AC coupling is established; the voltage measurement modeis entered, using the single-

5-21Chapter 5, FRONT PANEL OPERATIONFigure 5-15, Sensitivity Control - Voltage Input ModeWhen set to current input mode, the instrument’s full-scale c

5-22Chapter 5, FRONT PANEL OPERATIONAC GainIf the AC Gain control is set to Manual (using the Input Setup menu), then thiscontrol allows it to be adju

5-23Chapter 5, FRONT PANEL OPERATIONSlopeThe roll-off of the output filters is set, using this control, to any value from 6 dB to24 dB/octave, in 6 dB

5-24Chapter 5, FRONT PANEL OPERATIONOscillator AmplitudeThe amplitude of the instrument’s internal oscillator may be set, using this control, toany va

5-25Chapter 5, FRONT PANEL OPERATIONDAC 2This control sets the voltage appearing at the rear panel DAC2 output connector toany value between +10 V and

5-26Chapter 5, FRONT PANEL OPERATIONReference PhaseThis control allows the reference phase to be adjusted over the range -360° to + 360°in 10m° steps,

5-27Chapter 5, FRONT PANEL OPERATIONX %fsFigure 5-27, X Output as % Full-ScaleShows the X output as a percentage of the selected full-scale sensitivit

5-28Chapter 5, FRONT PANEL OPERATIONMAG %fsFigure 5-29, Magnitude Output as % Full-ScaleShows the signal magnitude, where magnitude = √((X output)2 +

5-29Chapter 5, FRONT PANEL OPERATIONPhase in DegreesFigure 5-31, Phase Output in DegreesShows the relative phase, where phase = tan-1 (Y output/X outp

vTABLE OF CONTENTSAppendix B, PinoutsB.1 RS232 Connector Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-30Chapter 5, FRONT PANEL OPERATIONX Volts (or Amps)Figure 5-33, X Output in Volts or AmpsShows the X output directly in terms of volts or amps (depe

5-31Chapter 5, FRONT PANEL OPERATIONMAG Volts (or Amps)Figure 5-35, Magnitude Output in Volts or AmpsShows the signal magnitude, where magnitude = √((

5-32Chapter 5, FRONT PANEL OPERATIONRatioFigure 5-37, Ratio OutputShows the ratio, where ratio = (X output / ADC1 Input), usually used to compensatefo

5-33Chapter 5, FRONT PANEL OPERATIONADC1 VoltsFigure 5-39, ADC 1 InputShows the voltage applied to the rear panel ADC1 auxiliary input.ADC2 VoltsFigur

5-34Chapter 5, FRONT PANEL OPERATIONX OffsetFigure 5-41, X Output Offset ControlThis control allows the X output offset to be adjusted, using the lowe

5-35Chapter 5, FRONT PANEL OPERATIONwarning message OFFSET!The instrument provides a quick way to switch between the following pairs ofoutputs, by sim

5-36Chapter 5, FRONT PANEL OPERATION

Computer OperationChapter 66-16.1 IntroductionThe model 7220 includes both RS232 and IEEE-488 (also known as GPIB forGeneral Purpose Interface Bus) in

6-2Chapter 6, COMPUTER OPERATION6.2.04 Internal Oscillator Frequency Sweep GeneratorThe instrument’s internal oscillator may be swept in frequency bot

6-3Chapter 6, COMPUTER OPERATIONThe main advantages of the RS232 interface are:1. It communicates via a serial port which is present as standard equip

viTABLE OF CONTENTS

6-4Chapter 6, COMPUTER OPERATIONWhere the RS232 parameters of the terminal or computer are capable of being set toany desired value, an arbitrary choi

6-5Chapter 6, COMPUTER OPERATIONBecause of the parallel nature of the GPIB and its very effective use of the controllines including the implementation

6-6Chapter 6, COMPUTER OPERATIONparameter byte. The default (power-up) state of this bit is for it to be asserted.The program RSCOM2.BAS in section C.

6-7Chapter 6, COMPUTER OPERATIONsent without the optional parameters, the response consists of a transmission ofthe present values of the parameter(s)

6-8Chapter 6, COMPUTER OPERATIONrespectively. In GPIB communications, the use of these bits can lead to a usefulsimplification of the control program

6-9Chapter 6, COMPUTER OPERATION6.3.14 Service RequestsThe interface defined by the IEEE-488 standard includes a line (pin 10 on theconnector) called

6-10Chapter 6, COMPUTER OPERATION6.4 Command DescriptionsThis section lists the commands in logical groups, so that, for example, all commandsassociat

6-11Chapter 6, COMPUTER OPERATIONCP [n] Input coupling controlThe value of n sets the input coupling mode according to the following table:n Coupling

6-12Chapter 6, COMPUTER OPERATIONASM Perform an Auto-Measure operationThe instrument adjusts its full-scale sensitivity so that the magnitude output l

6-13Chapter 6, COMPUTER OPERATIONn Notch filter mode0 60 Hz (and/or 120 Hz)1 50 Hz (and/or 100 Hz)Units made prior to June 1996 generate an Invalid Co

IntroductionChapter 11-11.1 How to Use This ManualThis manual gives detailed instructions for setting up and operating the EG&GInstruments Model 7

6-14Chapter 6, COMPUTER OPERATIONFRQ[.] Reference frequency meterIf the lock-in amplifier is in the EXT or EXT LOGIC reference source modes, theFRQ co

6-15Chapter 6, COMPUTER OPERATION17 10 s18 20 s19 50 s20 100 s21 200 s22 500 s23 1 ks24 2 ks25 5 ksThe TC. command is only used for reading the time c

6-16Chapter 6, COMPUTER OPERATIONAXO Auto-OffsetThe X and Y output offsets are turned on and set to levels giving zero X and Youtputs. Any changes in

6-17Chapter 6, COMPUTER OPERATIONXY[.] X, Y outputsEquivalent to the compound command X[.];Y[.]MAG[.] MagnitudeIn fixed point mode causes the lock-in

6-18Chapter 6, COMPUTER OPERATIONENBW[.] Equivalent noise bandwidthIn fixed point mode, reports the equivalent noise bandwidth of the output low-passf

6-19Chapter 6, COMPUTER OPERATIONCaution: Check that the computer program does not automatically add a carriagereturn or carriage return-line feed ter

6-20Chapter 6, COMPUTER OPERATIONFSTEP[.] [n1 n2] Oscillator frequency sweep step size and typeThe frequency may be swept either linearly or logarithm

6-21Chapter 6, COMPUTER OPERATIONBYTE [n] Digital output port controlThe value of n, in the range 0 to 255, determines the bits to be output on the re

6-22Chapter 6, COMPUTER OPERATIONTADC parameter Effect on CBD parameter0 none1 none2 automatically set to 323 automatically set to 964 automatically s

6-23Chapter 6, COMPUTER OPERATION6.4.09 Output Data Curve BufferCBD [n] Curve buffer defineDefines which data outputs are stored in the curve buffer w