Abstract: Various illustrative embodiments pertain to a signal quality evaluation system having a decision feedback equalizer (DFE) and a signal quality evaluator. The DFE receives an input signal containing symbols that represent digital data and uses the symbols to generate multiple detection thresholds. Each detection threshold is one of several detection thresholds that can be generated by the DFE by processing one or more symbols present in the input signal prior to a current clock cycle of a clock that is recovered from the input signal. The signal quality evaluator uses the detection thresholds provided by the DFE to detect transitions in the input signal. The signal quality evaluator may execute jitter measurements and/or time interval error (TIE) measurements by evaluating the transitions in the input signal.

Abstract: Disclosed is an improved real-time oscilloscope (“IRTO”) for generating a fast worst-case real-time eye diagram from an input signal. The IRTO may include signal conditioning circuitry, a digitizer, an acquisition memory, a clock and data recovery (“CDR”) module, a worst-case real-time eye diagram rendering (“WRTER”) module, and a display.

Abstract: Disclosed is an improved real-time oscilloscope (“IRTO”) for generating a fast worst-case real-time eye diagram from an input signal. The IRTO may include signal conditioning circuitry, a digitizer, an acquisition memory, a clock and data recovery (“CDR”) module, a worst-case real-time eye diagram rendering (“WRTER”) module, and a display.

Abstract: An instrument screen display includes a unique marker that provides the correlation and navigation through the analog data. The marker tells the user which packet or symbol is being displayed in the analog trace. The selected line in the listing (listing row that is blue) and the blue line on the trace above indicate which packet is selected for the purpose of showing details and packet data in the other tabs in the listing window. In addition to correlation, navigation can occur from either display. This type of marker is an innovative approach to correlating and navigating the disparate data types displayed on a modern oscilloscope.

Abstract: Events discovered by an automatic measurement subsystem in the trace of a DSO are visited using a set of event navigation controls. In a TIME Mode the controls operate to display the first of those events, display the next event after the one currently displayed, display the previous event before the one currently displayed, and, display the last event. In a SEVERITY Mode the controls operate to display the best of those events, display the next best event relative to the one currently displayed, display the next worst event before the one currently displayed, and, display the worst event. The sets of navigation controls may be a mode control menu accompanied by four stylized arrow shaped buttons within a GUI that are clicked on by an operator using a mouse. One set of arrow shaped button can serve both modes, or different sets of buttons can serve each respective mode.

Abstract: Events discovered by an automatic measurement subsystem in the trace of a DSO are visited by equipping the DSO with sets of event navigation controls (F, N, P & L and B, NB, NW & W). In a TIME Mode the controls operate to display the earliest or first (F) of those events, display the next (N) event after the one currently displayed, display the previous (P) event before the one currently displayed, and, display the last (L) event. In a SEVERITY Mode the controls operate to display the best (B) of those events, display the next best (NB) event relative to the one currently displayed, display the next worst (NW) event before the one currently displayed, and, display the worst (W) event. The sets of navigation controls may be a mode control menu accompanied by four stylized arrow shaped buttons within a GUI (Graphical User Interface) that are clicked on by an operator using a mouse. One set of arrow shaped button can serve for both modes, as their behaviors are similar.

Abstract: A Composite Trigger for a DSO provisionally honors a conventional hardware trigger by algorithmically investigating the content of the associated Acquisition Record for a selected signal attribute (a S/W Trigger). If found, the hardware trigger is fully honored by displaying the Acquisition Record with a previously selected time scale and with the time reference set to where in the trace the selected signal attribute occurs. The selected attribute may include the occurrence of a stated value or stated range of values for any automatic measurement upon a trace that the 'scope is otherwise equipped to perform. In addition to being based on existing automatic measurements, the Composite Trigger can also be satisfied whenever subsequent investigation determines that a segment of trace described by the Acquisition Record does or does not pass through one or more zones defined relative to an existing time reference.

Abstract: A measurement system for analyzing data values that are stored in memory and that represent a sampled electrical signal under analysis (SUA). Each of the data values represents the SUA at respective points in time over a time interval during which the SUA was sampled. The stored data values constitute a main data record. The system includes processing logic that is configured to generate at least a first reduced data record from the main data record. The first reduced data record comprises a subset of the data values of the main data record. The first reduced data record is processed by the processing logic to locate an edge (i.e., a voltage transition) in the first reduced data record. Thus, it is not necessary that the main data record, which is more voluminous than the first reduced data record, be used to locate the edge.

Abstract: A measurement system for analyzing data values that are stored in memory and that represent a sampled electrical signal under analysis (SUA). Each of the data values represents the SUA at respective points in time over a time interval during which the SUA was sampled. The stored data values constitute a main data record. The system includes processing logic that is configured to generate at least a first reduced data record from the main data record. The first reduced data record comprises a subset of the data values of the main data record. The first reduced data record is processed by the processing logic to locate an edge (i.e., a voltage transition) in the first reduced data record. Thus, it is not necessary that the main data record, which is more voluminous than the first reduced data record, be used to locate the edge.

Abstract: The method and apparatus of the present invention vary the rate of movement of a marker along a waveform. The rate of movement is varied by changing the distance increment the marker moves in response to a movement command. In a first embodiment of the invention the marker movement increment is proportional to the reciprocal of the derivative of the waveform amplitude with respect to time. In a second embodiment the marker moves only to specified points of interest along the waveform which are calculated in real-time. In a third embodiment the increment depends on how long the input device has been activated. In a fourth embodiment the marker movement is interrupted when the marker steps onto or over a detent. Each embodiment of the present invention moves the marker along the waveform in a manner which improves the ability of the user to examine information of interest in detail while moving rapidly over information that is not of interest.