Agilent Technologies N5183A, E8663B Reading the Service Request Interrupt SRQ Using Visa and C

Programming Examples

GPIB Programming Interface Examples

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Reading the Service Request Interrupt (SRQ) Using VISA and C

This example demonstrates use of the Service Request (SRQ) interrupt. By using the SRQ, the computer can attend to other tasks while the signal generator is busy performing a function or operation. When the signal generator finishes its operation, or detects a failure, then a Service Request can be generated. The computer will respond to the SRQ and, depending on the code, can perform some other operation or notify the user of failures or other conditions.

This program sets up a step sweep function for the signal generator and, while the operation is in progress, prints out a series of asterisks. When the step sweep operation is complete, an SRQ is generated and the printing ceases.

Launch Microsoft Visual C++ 6.0, add the required files, and enter the following code into your .cpp source file. visaex10.cpp performs the following functions:

•error checking

•clears the signal generator

•resets the signal generator

•prompts user to manually begin the step sweep and waits for response

•clears the status register

•sets up the operation status group to respond to an end of sweep

•the data questionable status register is enabled to read an unleveled condition

•prompts user to manually set up the signal generator for an unleveled condition

•queries the data questionable status register for any set bits and converts the string data to numeric

•based on the numeric value, program checks for a corresponding status check value

•similarly checks for over or undermodulation condition

The following program example is available on the signal generator Documentation CD- ROM as visaex10.cpp.

//******************************************************************************

//

//PROGRAM FILE NAME:visaex10.cpp

//PROGRAM DESCRIPTION: This example demonstrates the use of a Service Request (SRQ)

//interrupt. The program sets up conditions to enable the SRQ and then sets the signal

//generator for a step mode sweep. The program will enter a printing loop which prints

//an * character and ends when the sweep has completed and an SRQ received.

//

//******************************************************************************

#include "visa.h" #include <stdio.h> #include "StdAfx.h"

94 Agilent N518xA, E8663B, E44x8C, and E82x7D Signal Generators Programming Guide