HP 16550A User Reference page 154

The Waveform Menu
Stop Measurement Field
Compare
When Compare is selected, a repetitive run will be stopped when a
comparison of data in the Listing menu and data and criteria in a compare
image matches an equality selection. The equality selection is set from the
Equal/Not Equal selection pop-up menu.
Equal The data and compare criteria in the Compare menu must be
equal to the data in the Listing menu.
Not Equal The data and compare criteria in the Compare menu must
not be equal to the data in the Listing menu.
Compare options menu
Equal / Not Equal Selection Menu
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