Agilent Technologies ESA-E Series Programmer's Manual page 74

Programming Examples
Using Marker Peak Search and Peak Excursio n
double dMarkerFreq = 0 ;
double dMarkerAmpl = 0 ;
float fPeakExcursion =0 ;
long lOpc = OL ;
/*Open an HP-IB session at address 18 .* /
viStatus =viOpenDefaultRM(&defaultRM) ;
viStatus =viOpen(defaultRM,"GPIBO : :18",VI NULL,VI NULL,&viESA) ;
if(viStatus )
{
printf("Could not open a session to HP-IB device at address 181\n") ;
exit(0) ;
}
/*Clear the instrument* /
viClear(viESA) ;
/*Reset the instrument* /
viPrintf(viESA,"*RST\n") ;
/*Set the analyzer center frequency to 5OMHZ* /
viPrintf(viESA,"SENS :FREQ :CENT 50e6\n") ;
/*Set the analyzer span to 50MHZ* /
viPrintf(viESA, " SENS :FREQ :SPAN 50e6\n") ;
/*Display the program heading * /
printf("\n\t\t Marker Program \n\n" ) ;
/* Check for the instrument model number and route the 50MHz signal accordingly* /
Route50MHzSignal() ;
/*Set analyzer to single sweep mode* /
viPrintf(viESA,"INIT :CONT 0 \n") ;
/*User enters the peak excursion value* /
printf("\t Enter PEAK EXCURSION in dB : ") ;
scanf( "%f",&fPeakExcursion) ;
/*Set the peak excursion* /
viPrintf(viESA,"CALC :MARK :PEAK :EXC %1fDB \n", fPeakExcursion) ;
/*Set the peak thresold * /
viPrintf(viESA,"CALC :MARK :PEAK :THR -90 \n") ;
/*Trigger a sweep* /
viPrintf(viESA,"INIT :IMM\n") ;
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Chapter 3