HP Drive manual Set the Reading Timeout/Display the Reading, Error Checking, Close the Session

Set the Reading Timeout/Display the Reading

Create a variable to represent the reading and make a reading with a timeout of 1 second (1000 milliseconds).

1Type

double reading = dmm->Measurement->Read(1000);

2To display the reading, use printf. Type wprintf(L“Reading: %g\n”, reading);

Error Checking

To catch errors in the code, activate error checking.

1Surround the preceding statements with a try block. Add the following lines as shown in the illustration above:

try {

}

2Process errors in a catch block. Type catch (_com_error e) {

wprintf(L“Error: %s”, e.ErrorMessage());

}

Close the Session

To close out the instance of the driver and free resources, type

dmm->Close();

The final code should look like the following: #include "stdafx.h"

#import "IviDriverTypeLib.dll" no_namespace #import "IviDmmTypeLib.dll" no_namespace #import "GlobMgr.dll" no_namespace #import "Agilent34401.dll" no_namespace int IVI_Demo()

{

HRESULT hr;

hr = CoInitialize(NULL); if(FAILED(hr))

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Using IVI with Visual C++ • 21

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