HP 8163A Series Programming Manual page 133

How to Measure Power using FETCh and READ
/* read 10 values and display the result; */
for (i = 0; i < 10; i++)
{
/* Now because an averaged value is available, the value will be fetched*/
errStatus = viQueryf(vi,"%s","%s","FETCH1:CHAN1:POW?\n",replyBuf);
if (errStatus < VI_SUCCESS) checkError(vi,errStatus);
/* two consecutive values are compared; if they are equal it will be marked;
because no evaluation is triggered, all values will be the same*/
if(i)
{
if(!strcmp(compBuf,replyBuf))
{
printf("Same:%s\n",replyBuf);
}
else printf("New:%s\n",replyBuf);
}
else printf("First:%s\n",replyBuf);
strcpy(compBuf,replyBuf);
}
/* now the read command is used in the same manner to
demonstrate the difference between fetch and read*/
/* read also 10 values, compare them and display the result; */
for (i = 0; i < 10; i++)
{
/*
In comparision to the "FETCH" command, the "READ" command implies
triggering a measurement.
Make sure the timeout set is greater than the adjusted
averaging time, so that the READ command will not time out.
*/
/* send the read command */
errStatus = viQueryf(vi,"READ1:CHAN1:POW?\n","%t",replyBuf);
checkError(vi,errStatus);
if(i)
{
if(!strcmp(compBuf,replyBuf)) printf("Same:%s",replyBuf);
else printf("New :%s",replyBuf);
}
else printf("\nFirst:%s",replyBuf);
/*copy new value to compare buffer*/
strcpy(compBuf,replyBuf);
}
/* loop, until a key is pressed */
HP 8163A Lightwave Multimeter, HP 8164A Lightwave Measurement System,
& HP 8166A Lightwave Multichannel System User's Guide, E1299
Programming Examples
133