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These examples are purely illustrative, but you can easily imagine that with a VBScript you can add value to the
oscilloscope in a very short time. This gives you an instrument that does exactly what you want, time after time,
by using your stored setups and scripts.
What can you do with a customized instrument?
If you require a result that can be derived logically from the input waveform, you can do it. Many calculations can
be done with remarkably small scripts, but if you have no time for scripting, you can use one of the proprietary
packages, such as Excel, MATLAB, or Mathcad, which offer immense processing power.
S
D
CALING AND
ISPLAY
Scripting and programming allow a large variety of opportunities. You may, for example, be using transducers. If
so, you can change the units of your waveforms, and write N (newtons), J (joules) and so on, and you can
introduce scaling factors. If the transducers are non-linear, you can correct for that, too. You can also transform
horizontal scales and vertical scales by manipulating the data. Logarithmic scales in amplitude and frequency are
often required. Squaring and taking square roots are needed in certain applications. Here is a picture showing
some graphs related to white noise, showing ways of detecting small deviations from the true distribution. The
lower two graphs were generated and placed in one trace using a VBScript.
In the next example, four graphs are placed in one trace.
G
W
OLDEN
AVEFORMS
This is a rich field for VBS. An example was given earlier. The only limits to the shapes that can be generated are
the vertical resolution and the number of samples.
A
– DVI D
PRACTICA
L EXAMPLE
The next example is a measurement of DVI Data-Clock skew jitter measurement, using a VBScript to emulate the
PLL. A solution to a practical measurement problem was shown earlier.
These are just a few of the many solutions that can be created.
Number of Samples
The various math packages can process samples as follows:
The number of samples that MATLAB can process is determined by memory option, as follows:
Memory Length
STD, S, M
L, VL
XL
XXL
WRXi-OM-E Rev C
-C
ATA
LOCK SKEW
Excel
65,535 samples
Mathcad
5 MS
System DRAM
256 MB
512 MB
1 GB
2 GB
O
PERATOR
Buffer Length
40 MB
200 MB
400 MB
400 MB
'
M
S
ANUAL
173
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