Teledyne LeCroy SDA II - Manual (Page 20)

Serial Data Analysis II Software
7. Touch inside the X field and enter a value from 0 to 100%. As you enlarge the mask's margin, you
lengthen the horizontal dimension, bringing the mask closer to the crossing points of your eye dia-
gram. This reduces the amount of jitter that can still pass the eye.
8. Touch inside the Y field and enter a value from 0 to 100%. As you enlarge the mask's Y margin, you
widen the vertical dimension, bringing the mask closer to the top and bottom of your eye diagram.
This reduces the amount of vertical eye closure that can still pass the eye.
9. Margin only center area checkbox - Check to have only the center hexagon or diamond expand
when the mask margin is set to a value other than 0%
Eye Modes
There are four eye modes you can choose when setting up an eye measurement:
Single Eye- This mode overlays all the UIs from all acquisitions.
Dual Eye Transition/Non-Transition - Divides the signal's UIs into two separate eyes: ones comprised of
UIs starting with a transition and one comprised of UIs without. The PCIe standard refers to these as Tran-
sition and Non-Transition eyes. This display mode is useful for those serial data standards using mask
testing for both types of eyes (PCI Express and FB-DIMM Point-to-Point).
Dual Eye Gated (Qualified) Eye Diagram - The Gated Eye Diagram mode uses a separate signal (the Gate
or qualifier) to create dual eye diagrams based on the polarity of the Gate.
Dual Eye FSB (Front Side Bus) - Operates similar to Sequential mode, but divides the results into two sep-
arate eyes based on which of a pair of signals occurred first. When Dual Eye FSB is selected, additional
fields are then shown.
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