Chapter 5: Reference

The Sampling Tab

2.The stable region(s) are too small for eye finder to detect.

In this case you must resort to adjusting the sample position manually and checking its validity by running an ordinary analyzer measurement to see if the data values you expect are sampled. You can adjust the sample position manually by selecting the arrow buttons or by dragging the blue sampling position indicator in the display.

"Only a few transitions detected. Change stimulus or increase measurement duration (Advanced Settings)."

The signal on this channel was observed to toggle fewer than 500 times. The characterization may be accepted as it stands or you may wish to change the stimulus program or diagnostic in the device under test to increase the toggle rate.

Another option is to select "Long" in the Eye Finder Advanced Settings dialog (accessed from the "Advanced..." button on the Eye Finder Setup tab or the "Advanced Settings..." menu pick under the EyeFinder pull down menu). Using the "Long" setting won't necessarily make the message go away, but it will ensure that eye finder has the opportunity to observe a more significant number of transitions on the channel.

"Run Eye Finder to characterize this channel."

Select this channel (or a label that contains it) and run eye finder to characterize the channel. Only channels selected for a measurement are updated when the measurement finishes. Information about other channels is not changed.

"See individual channels for message(s)"

There is a message for one or more the the channels assigned to this bus label. Expand the label (using either the popup menu on the label in the display or the "Results" pulldown menu), then scroll down to the channel with a message icon and display its message (either by selecting the yellow message icon or by using the popup menu).

"The stable region extends beyond the limits of the display."

This channel is active, but the signal does not switch within 5 nsec before or after the clock. For example, this could occur if the propagation delay in the device under test from clock to data is greater

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Agilent Technologies 16760A manual Run Eye Finder to characterize this channel, See individual channels for messages, 166