:MEASure:EYE:PAM:UNDershoot

Meas. mode:
Eye
Waveform type:
PAM
Package License:
RND
MFG
SNT
Flex Apps:
FlexDCA
FlexRT
PAM Undershoot Commands

Command Syntax

:MEASure:EYE:PAM:UNDershoot

Query Syntax

:MEASure:EYE:PAM:UNDershoot?

Moves the PAM4 Undershoot measurement to the top of the Eye Mode 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. PAM4 Undershoot is an IEEE 802.3cu compatible measurement.

The PAM Undershoot measurement is reported as a percentage and is defined as:

Where:

  • Pmin is based on a 1e-2 hit ratio, where Pmin is the largest power level that results in the number of samples below that level not exceeding the product of hit ratio and total number of observed samples. All samples are acquired in a single unit interval eye diagram.

By default, the hit ratio 1e-2 is based on the IEEE 802.3cu standard. However, you can change this ratio using the :MEASure:EYE:PAM:UNDershoot:THRatio command.

Requires FlexDCA revision A.06.60 and above.

Measurement Identification

Avoid subtle programming errors! To ensure that the correct measurement is installed or queried, always explicitly identify a measurement when installing a measurement or querying a measured value, status, or detail. To identify a measurement, specify the measurement's source waveform (:SOURce child command). With some measurements, you may also need to specify other identifying values. Generally, when selecting a measurement using FlexDCA's GUI, if a dialog appears prompting you to select values, you should explicitly specify these values when remotely identifying the measurement. More information.

For example, to return the status of the measurement, :

flex.write(':SOURce CHAN1A')
if flex.query(':STATus?') == 'CORR';
    measurement = flex.query('?')
else:
	details = flex.query(':STATus:DETails?')
	reason = flex.query(':STATus:REASon?')

Child commands for measurement identification:

  • :MEASure:EYE:PAM:UNDershoot:SOURce
  • :MEASure:EYE:PAM:UNDershoot:THRatio

Common Measurement Queries