Viewing Sampled Data - Agilent Technologies 3458A User Manual

Viewing Sampled Data

10OPTION BASE 1
20INTEGER Num_samples,Inc,I,J,K,L
30INTEGER Int_samp(l:l000) BUFFER
40ALLOCATE REAL Wave_form(l:Num_samples)!CREATE ARRAY FOR SORTED DATA
50ALLOCATE REAL Samp(l:Num_samples)
60Num_samples=1000
70Eff_int=2.0E-6
80ASSIGN @Dvm TO 722
90ASSIGN @Int_samp TO BUFFER Int_samp(*)
100OUTPUT @Dvm;"PRESET FAST;SSDC 10;SWEEP ";Eff_int, Num_samples
146 Chapter 5 Digitizing
The program on the following page plots digitized data to the controller's
CRT (this particular program uses sub-sampling and the subroutine Plot_it
does the actual plotting). This program is helpful when developing digitizing
programs (especially when sub-sampling) since it allows you to see the data
being captured. Since this program simply draws vectors between the
samples (linear interpolation), it works well when the sampling rate is greater
than 10 times the frequency of the signal being measured. If the sampling
rate is less than 10 times the frequency of the input signal, this program will
plot an incorrect representation of the input signal. Figure 34 shows a typical
plot produced by this program.
Note
The 3458 Option 005 Waveform Analysis Library is a software package
designed to capture and process digitized data. It contains routines that
initialize the system, capture data, compare data, compute parameters on
the data, perform Fourier transforms on the data, and plot/output the data.
Contact your Agilent Sales Office for more information.
Figure 34. Typical plotted waveform
!COMPUTER ARRAY NUMBERING STARTS AT 1
!DECLARE VARIABLES
!CREATE INTEGER BUFFER
!CREATE ARRAY FOR SAMPLES
!DESIGNATE NUMBER OF SAMPLES
!DESIGNATE EFFECTIVE INTERVAL
!ASSIGN MULTIMETER ADDRESS
!ASSIGN I/O PATH NAME TO BUFFER