:MEASure:EYE:PAM:VECLosure

PAM Vert. Eye Closure Commands

Command Syntax

:MEASure:EYE:PAM:VECLosure

Query Syntax

:MEASure:EYE:PAM:VECLosure?

Returns the measurement for the eye specified with :MEASure:EYE:PAM:VECLosure:EYE.

Description

Returns the PAM Vertical Eye Closure measurements (VEC) located in the Results measurement results. Displays the measurement if it is not already shown on the table. The query form of the command returns the measured value. Select the eye measurement to be returned using the :MEASure:EYE:PAM:VECLosure:EYE command.

The Vertical Eye Closure (VEC) PAM measurement is a measure of the ratio of the ideal eye opening (separation between the average levels surrounding the eye) to the measured eye height of that eye reported in dB. This measurement can also be used for NRZ coded signals. VEC is measured for each of the PAM eyes. The higher the result (decibels) the more the eye is closed. This measurement is IEEE 802.3ck compliant.

Eye Height is measured with the same algorithm as is used for the PAM Eye Heights measurement (:MEASure:EYE:PAM:EHEight).

Use the :MEASure:EYE:PAM:VECLosure:DEFine:EOPening command to define the eye opening: zero hits or at probability.

The IEEE method of measuring VEC in would be to select the Reference to Eye Opening and the Eye Opening Definition to At Probability with a probability of 1.0E–5.