Filter
Top Products
122 Chapter 3
Programming Examples
Reading Trace Data Using 32-bit Real Format (GPIB)
/*Program Variables*/
ViStatus viStatus= 0;
ViChar _VI_FAR cResult[5000] = {0};
ViReal32 dTraceArray[401] = {0};
char cBufferInfo[6]= {0};
long lNumberBytes =0L;
long lOpc =0L;
unsigned long lRetCount = 0L;
int iSize = 0;
/*BytesPerPoint is 4 for Real32 or Int32 formats, 8 for Real64, and 2 for Uint16*/
int iBytesPerPnt = 4;
int iSwpPnts = 401;
int iDataBytes=1604;
int iHeaderBytes=6;
FILE *fTraceFile;
/* Open a GPIB session at address 18*/
viStatus=viOpenDefaultRM(&defaultRM);
viStatus=viOpen(defaultRM,"GPIB0::18",VI_NULL,VI_NULL,&viESA);
if(viStatus)
{
printf("Could not open a session to GPIB device at address 18!\n");
exit(0);
}
/*Clear the instrument */
viClear(viESA);
/*Reset the instrument. This will set number of sweep points to default of 401*/
viPrintf(viESA,"*RST\n");
/*Display the program heading */
printf("\n\t\t Read in Trace Data using 32-bit Real Format (using GPIB) \n\n" );
/* Set the input port to the 50MHz amplitude reference*/
Route50MHzSignal();
/*Query number of sweep points per trace (firmware revision A.04.00 and later)*/
/*For firmware revisions prior to A.04.00, the number of sweep points is 401*/
iSwpPnts=401;
viQueryf(viESA,"SENSE:SWEEP:POINTS?\n","%d",&iSwpPnts);
/*Calculate number of bytes in the header. The header consists of the "#" sign*/
/*followed by a digit representing the number of digits to follow. The digits */
/*which follow represent the number of sweep points multiplied by the number */
/*of bytes per point. */
iHeaderBytes = 3; /*iDataBytes >3, plus increment for "#" and "n"*/