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•Simulate=1 in the Options parameter sets the driver to simulation mode
•&session assigns the Instrument Handle to the variable “session” defined above
Configure the Instrument
1To set the range to 1.5 volts and resolution to 0.001 millivolts, type:
checkErr( hp34401a_ConfigureMeasurement (session, HP34401A_VAL_DC_VOLTS, 1.5, 0.001));
Set the Trigger and Trigger Delay
1To set the trigger source to immediate and the trigger delay to 0.01 seconds, type:
checkErr( hp34401a_ConfigureTrigger (session, HP34401A_VAL_IMMEDIATE, 0.01));
Set the Reading Timeout/Display the Reading
1To take a reading from the instrument and to set the reading timeout to 1 second (1000 ms) type:
checkErr( hp34401a_Read (session, 1000, &reading);
Note: The Read function takes a reading from the instrument and assigns the result to the variable “reading” defined above.
2To display the reading, use a printf statement. Type printf (“Reading = %f”, reading);
Close the Session
To close out the instance of the driver and free resources, type
If (session)
hp34401a_Close(session);
The final code should contain the code below:
#include "stdafx.h" #include <hp34401a.h>
#ifndef checkErr
#define checkErr(fCall) \
if (error = (fCall), (error = (error < 0)? error : VI_SUCCESS)) \
{goto Error;} else error = error
