HP ESA-E Series - Page 111

Chapter 3 3-47
Programming Examples
Measuring Noise
Visession defaultRM, viESA;
ViStatus errStatus;
ViChar cIdBuff[256]={0};
char cEnter = 0;
int iResult = 0;
long lOpc = 0L ;
/*Set the input port to the 50 MHz amplitude reference*/
void Route50MHzSignal()
{
viQueryf(viESA, "*IDN?\n", "%t", &cIdBuff);
iResult = (strncmp( cIdBuff, hpESA_IDN_E4401B,
strlen(hpESA_IDN_E4401B)) && strncmp( cIdBuff,
hpESA_IDN_E4411B, strlen(hpESA_IDN_E4411B)));
if( iResult == 0 )
{
/*Set the input port to the 50 MHz amplitude reference
for HP models E4401B or E4411B*/
viPrintf(viESA,"CAL:SOUR:STAT ON \n");
}
else
{
/*For analyzers having frequency limits 3 GHz, prompt
the user to connect the amplitude reference output to the RF
input*/
printf ("Connect amplitude reference output to the
input \n");
printf ("......Press any key to continue \n");
scanf( "%c",&cEnter);
/*Externally route the 50 MHz signal*/
viPrintf(viESA,"CAL:SOUR:STAT ON \n");
}
}
void main()
{
/*Program Variables*/
ViStatus viStatus = 0;
double dMarkAmp = 0.0;
long lOpc=0L;
/*Open an HP-IB session at address 18*/
viStatus=viOpenDefaultRM(&defaultRM);
viStatus=viOpen(defaultRM,"GPIB0::18",VI_NULL,VI_NULL,&
viESA);
if(viStatus)