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Lesson 4Instrument driving, Data Acquisition and Waveforms

A. GPIB demos

B. About plug-in data acquisition (DAQ) boards

C. About the organization of the DAQ VIs

D. How to perform a single analog input

E. About the DAQ Wizards

F. About waveform analog input

G. How to write waveforms to file

H. How to output an analog signal

I. How to use counter/timers

J. USB DAQ--NI-DAQ mx Base devices

You Will Learn:

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Instrument Control OverviewControl any instrument if you know the following:

Type of connector on the instrument Type of cables needed Electrical properties involved Communication protocols used Software drivers available

Instruments Computer

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GPIB Communication

1965 1987 1990 1992 19931975

HPdesignsHP-IB

HP-IBbecomesIEEE488

IEEE488.2adopted

IEEE488becomes

IEEE488.1

SCPIintroduced

IEEE488.2revised

HS488proposed

GPIB Instrument

GPIB Cable

GPIB Interface

1999

HS488approved

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GPIB Hardware Specifications

Max cable length betweendevices = 4 m (2 maverage)

Max cable length = 20 m

Max number of devices =15 (2/3 powered on)

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DIO5DIO6DIO7DIO8REN

GND (TW PAIR W/DAV)GND (TW PAIR W/NRFD)GND (TW PAIR W/NDAC)GND (TW PAIR W/IFC)GND (TW PAIR W/SRQ)GND (TW PAIR W/ATN)SIGNAL GROUND

DIO1DIO2DIO3DIO4EOI

DAVNRFDNDAC

IFCSRQATN

SHIELD

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GPIB Software Architecture Windows

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Detecting GPIB Board and Instruments Measurement & Automation Explorer

(MAX)

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Use SR830.vi to control the lock-in amplifier, and

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Scan_freq1.vi to do a frequency scan

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Use Tek2440_Graphed.vi to control the Oscilloscope and measure sine

Wave from the lock-in:0.05V,Sweeps5E-4And trigger Auto with lock-in

30 mV at 1KHz

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Use Tek2440_Graphed1.vi to control the Oscilloscope and measure the

pulse from the trigger:0.05V,Sweeps2E-8And trigger Auto

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Others: spectrometerAndor software

SR245computer interface

.

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Data acquisition (DAQ)library supports all DAQboards

LabVIEW uses the NI-DAQdriver-level software

DAQ boards forAnalog I/ODigital I/OCounter/timer I/O

Data acquisition systemcomponents

OverviewThe fundamental task of all measurement systems is the measurement

and/or generation of real-world physical signals. Measurement deviceshelp you acquire, analyze, and present the measurements you take.

We acquire and convert physical signals, such asvoltage, current, pressure, and temperature, into digital formatsand transfer them into the computer.

Popular methods for acquiring data: plug-inDAQ and instrument devices, GPIB instruments, PXI (PCIeXtensions for Instrumentation) instruments, and RS-232instruments.

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DAQ Software Architecture

Windows

LabVIEW for Windows

DAQ Library VIs

Windows Device Manager

nidaq32.dll forWindows

Windows Registry

DAQ Device

DAQ-STC

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DAQ Hardware Configuration Measurement & Automation Explorer (MAX) by selecting

Tools>>Masurement & Automation Explorerin LabVIEW

View

Configure

and Test

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Hardware Connections

BNC-2120

SCB-68

SC-2075

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Hardware ConnectionsNote:

The channels available depends

on the DAQ card we use.

For instance,

DAQCard-AI-16E-4 NI lent to

us, there is no output channels

available

Lets configure the Card withMeasurement & AutomationExplorer

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Measurement FundamentalsIn Analytical Instrumentation,

we convert physical phenomena into data,using a transducer to convert aphysical phenomenon into an electricalsignal.

Summary of signal sources and

masurement systems

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DAQ VI Organization in LabVIEW software Analog Input

Analog Output

Digital I/O

Counter

Calibration andConfiguration

Signal Conditioning

A. labVIEW Traditional NI-DAQ

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J. USB DAQ--NI-DAQ mx Base devices

$195 CAD!!!

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I/O Connector

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Lets try remote VI:

472ai

472ao