Agilent Technologies 8163A Work Light User Manual


 
VISA Programming Examples How to Use VISA Calls
190 Agilent 8163A/B, 8164A/B & 8166A/B Mainframes, Fifth Edition
How to Use VISA Calls
The following example demonstrates how to communicate using VISA
calls. Also, the use of instrument identification commands is
demonstrated.
#include <stdio.h>
#include <stdlib.h>
#include <visa.h>
/* This function checks and displays errors, using the error query of
the instrument;
Call this function after every command to make sure your commands
are correct */
void checkError(ViSession session, ViStatus err_status )
{
ViStatus error;
ViChar errMsg[256];
/* queries what kind of error occurred */
error = viQueryf(session,"%s\n","%t","SYST:ERR?",errMsg);
/*if this command times out, a system error is probable;
check the GPIB bus communication */
if (error == VI_ERROR_TMO)
{
printf("System Error!\n") ;
exit(1);
}
else
{
/* display the error number and the error message */
if(errMsg[0] != '+')
printf("error:%ld --> %s\n", err_status,errMsg) ;
}
}
void main (void)
{
ViStatus errStatus; /*return error code from visa call */
ViSession defaultRM; /*default visa resource manager variable*/
ViSession vi; /*current session handle */
ViChar replyBuf[256]; /*buffer holding answers from the
instrument*/
ViChar c;