Polygon Masks In The Oscilloscope - HP 54710A User's Reference Manual

Mask Menu

Polygon Masks in the Oscilloscope

Polygon Masks in the Oscilloscope

The oscilloscope has three features that use a specific data base that uses a
different memory area than the waveform record for each channel. The three
features that use the data base are histograms, mask testing, and color
graded display. When any one of these three features are turned on, the
oscilloscope starts building the data base. The data base is the size of the
graticule area, which is 256 pixels high by 451 pixels wide. Behind each pixel
is a 16-bit counter. When color graded display, mask testing, or histograms
are turned on, a data base is built by incrementing the 16-bit counters each
time a pixel is hit by data from a channel or function. The maximum count
(saturation) for each counter is 65,535. You can check to see if any of the
counters are close to saturation by going to the display menu and turning on
the color graded display feature. The color graded display menu uses colors
to represent the number of hits on various areas of the display.
The data base continues to build until the oscilloscope stops acquiring data
or all three functions (color graded display, mask testing, and histograms)
are turned off. The oscilloscope stops acquiring data when the power is
cycled, the Stop/Single hardkey is pressed, or the run until softkey in the
mask, limit test, or histograms menus is set to stop acquiring data after a
specified number of waveforms or samples are acquired.
You can clear the data base by pressing the Clear display hardkey, cycling the
power, or turning off all three features that use the data base. The data base
does not differentiate waveforms from different channels or functions. If
three channels are turned on and the waveform from each channel happens
to light the same pixel at the same time, the counter is incremented by three.
However, it is not possible to tell how many hits came from each waveform.
You can separate waveforms by setting the display to two graphs or by
positioning the waveforms vertically with the channel offset. By separating
the waveforms you can avoid overlapping data in the data base caused by
multiple waveforms.
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