Agilent Technologies 1660A Series User Reference page 283

The Waveform Menu
Stop Measurement Field
X-O
The X-O option is available in the Timing analyzer and in the State analyzer
with its count set to Time.
When X-O is selected, a repetitive run is stopped when a comparison of the
time period between the X and O markers and one of the following time
period options is true:
Less Than X-O time must be less than the time value that you specify
in the Time field.
Greater Than X-O time must be greater than the time value that you
specify in the Time field.
In Range X-O pattern must be within the time range value that you
specify in the two Time fields.
Not in Range X-O pattern must not be within the time range value that
you specify in the two Time fields.
X to O option menu
X-O Field
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