Chapter 4 Command Reference

Introduction

:READ[[:SCALar]:<function>]?

This query provides a method of performing a :FETCh? on fresh data.

A common application is to use this command in conjunction with a :CONFigure to provide a capability like :MEASure? in which the application programmer is allowed to provide fine adjustments to the instrument state by issuing the corresponding commands between the :CONFigure and :READ?.

When [:SCALar]:<function> is specified, the instrument will retrieve the specified result if it matches the current measurement type or can be derived from the current measurement type. The only functions which can be derived from a different measurement type are:

frequency to/from period,

voltage minimum to/from voltage maximum,

voltage minimum to/from voltage peak-to-peak, and

voltage maximum to/from voltage peak-to-peak.

When [:SCALar]:<function> is omitted, the function specified/used by the last :CONFigure, :MEASure, :READ, or FETCh will be used,

if possible. This behavior is apparent when switching between frequency and period, or when switching among the voltage peaks functions.

Issuing this query while a measurement is in progress will result in this query aborting the current measurement and idling the measurement cycle before initiating the desired measurement,

and then waiting for the measurement to complete. Consequently, this has the effect of holding off further commands from being processed until the desired measurement completes. This hold-off action can only be canceled by the measurement completing, Device Clear, or power-on.

Programming Guide

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