JP2006162433A - Waveform display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a waveform display, capable of determining displayed intersection information to discriminate information based on the signal waveform data obtained by actual measurement from interpolated information. <P>SOLUTION: This waveform display for displaying signal waveforms A, B on a display screen 4a, together with a trace cursor C, based on the signal waveform data, and for displaying the intersection information of the signal waveforms A, B in an intersection of the signal waveforms A, B and the trace cursor C on a display screen 4a displays the intersection information to make a display mode, when the intersection is positioned in a portion displayed, based on the signal waveform data in the signal waveforms A, B so as to be mutually different from a display mode, when the intersection is positioned in a portion displayed by interpolation between the signal waveform data. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a waveform display device that displays a signal waveform and a trace cursor on a display unit.

As this type of waveform display device, the present applicant has disclosed a waveform display device in Japanese Patent Application Laid-Open No. 2003-315369. The waveform display device displays the signal waveform and the trace cursor on the display unit, and acquires intersection information (specifically, voltage, etc.) about the signal waveform at the intersection of the signal waveform and the trace cursor to display the display unit. It is configured so that it can be displayed.
JP 2003-315369 A (page 4)

  However, as a result of further examination of the waveform display device disclosed in the above publication, the present inventors have found that this waveform display device has the following problems. That is, although not specified in the above publication, the intersection information is usually displayed in the same display form in this type of waveform display device. Here, the display form refers to the font type, font size, presence / absence and type of font decoration, font brightness, and the like for the numerical values and characters for displaying the intersection information. For this reason, when the signal waveform displayed on the display unit is displayed by interpolating the signal waveform data based on the signal waveform data obtained by actual measurement, the trace cursor is displayed on any of the signal waveforms. Even when crossing the position, the intersection information is always displayed in the same display form. In this case, it is convenient if it is possible to determine whether the displayed intersection information is information based on signal waveform data obtained by actual measurement or interpolated information based on the display content of the display unit. Since this display device cannot make such a determination, it is preferable to improve this point.

  The present invention has been made to solve such a problem. Whether the displayed intersection information is information based on signal waveform data actually measured (sampled) or interpolated information. The main object is to provide a waveform display device that can discriminate based on the display content of the display unit.

  To achieve the above object, the waveform display apparatus according to claim 1 displays each signal waveform of the plurality of signals together with a trace cursor based on signal waveform data obtained by sampling the plurality of signals at different periods. And a waveform display device for displaying each intersection information of each signal waveform at each intersection of the signal waveform and the trace cursor on the display unit, wherein each intersection is the signal. The display form when the waveform is located at the part displayed based on the signal waveform data is different from the display form when each intersection is located at the part displayed by interpolating between the signal waveform data. As described above, each intersection information is displayed.

  The waveform display device according to claim 2 is the waveform display device according to claim 1, wherein the waveform display device is located only at a portion based on the signal waveform data in the selected signal waveform of the plurality of signal waveforms. Move and display the trace cursor.

  According to the waveform display device of claim 1, a display form when each intersection is located at a portion displayed based on the signal waveform data in each signal waveform, and each intersection is displayed by interpolating between the signal waveform data. By displaying each intersection information so that the display form when it is located at the specified part is different from each other, the waveform data of each signal waveform at the intersection with the trace cursor is actually sampled by just looking at the display form It is possible to accurately and easily determine whether the waveform data is the interpolated information or the interpolated information.

  According to another aspect of the waveform display device of the present invention, the trace cursor is moved and displayed so as to be positioned only at a portion based on the signal waveform data in the selected signal waveform among the plurality of signal waveforms. By moving and displaying, it is possible to display only the actually sampled waveform data for the selected signal.

  The best mode of a waveform display device according to the present invention will be described below with reference to the accompanying drawings.

  First, the configuration of the waveform display device 1 will be described with reference to the drawings.

  As shown in FIG. 1, the waveform display device 1 includes two A / D conversion units 2 and 3, a display unit 4, an operation unit 5, a control unit 6, and a memory 7. In this case, the A / D converter 2 converts the input signal S1 into waveform data (digital data indicating the voltage of the signal S1 as an example) D1 in synchronization with the sampling clock CL1 and outputs it to the controller 6 To do. The A / D conversion unit 3 converts the input signal S2 into waveform data (digital data indicating the voltage of the signal S2 as an example) D2 in synchronization with the sampling clock CL2, and outputs the waveform data to the control unit 5. Since the sampling clock CL1 and the sampling clock CL2 are generated by dividing the reference clock in the waveform display device 1, they are synchronized with each other. In this example, since the signal S1 changes at a higher speed than the signal S2, the sampling clock CL1 is set to a higher frequency than the sampling clock CL2.

  The display unit 4 includes a liquid crystal display as an example, and displays the signal waveforms A and B and the trace cursor C on the display screen 4a as shown in FIGS. The operation unit 5 includes an operation dial (not shown), and when the operation dial is operated, operation data D3 indicating operation contents (a rotation amount and a rotation direction of the operation dial) are generated and transmitted to the control unit 6. Output.

  The control unit 6 is composed of a CPU or the like, and executes a storage process for storing the waveform data D1 and D2 input from the A / D conversion units 2 and 3 in the memory 7. The control unit 6 displays the signal waveforms A and B and the trace cursor C on the display unit 4 based on the waveform data D1 and D2 stored in the memory 7 and the input operation data D3. Execute the process.

  Next, the operation of the waveform display device 1 will be described.

  First, the A / D converters 2 and 3 convert the input signals S1 and S2 into waveform data D1 and D2 in synchronization with the sampling clocks CL1 and CL2, respectively, and output them. The control unit 6 stores the input waveform data D1 and D2 in the memory 7 for a predetermined time (for example, the time that can be displayed on the display screen 4a of the display unit 4) in the input order by executing the storage process. Let

  Next, after finishing the storage process, the control unit 6 executes a display process. In this display process, the control unit 6 first reads the waveform data D1 and D2 from the memory 7 in the order in which they are stored, and also stores the order in which the waveform data D1 and D2 are stored and the sampling clocks CL1 and CL2. Based on one period (sampling period), the measurement time of each waveform data D1, D2 is calculated. Next, the control unit 6 displays the signal waveforms A and B on the display unit 4 with the horizontal axis as the time axis and the vertical axis as the voltage axis based on the values of the waveform data D1 and D2 and the calculated measurement time. Let When the signal waveform A is displayed on the display unit 4, the control unit 6 performs an interpolation display process (such as a linear interpolation display process) on the waveform data D1 actually acquired by sampling, thereby making the signal waveform A a continuous waveform. Display. Further, the control unit 6 displays the signal waveform B on the display unit 4 as a continuous waveform in the same manner as the signal waveform A. Further, the control unit 6 calculates the display position (position with respect to the horizontal axis) of the trace cursor C on the display unit 4 based on the input operation data D3, and updates and displays the trace cursor C at the calculated display position. . By the update display processing of the trace cursor C by the control unit 6, the trace cursor C is moved and displayed in the horizontal axis direction on the display screen 4a of the display unit 4 in conjunction with the operation on the operation dial of the operation unit 5.

  Further, in the display process, the control unit 6 for each of the signal waveforms A and B, the waveform data at the intersection with the trace cursor C (between the data of the actually sampled waveform data D1 and D2 or waveform data D2). Information such as voltage values obtained by interpolation (hereinafter also referred to as waveform data when not distinguished. Intersection information in the present invention) is always obtained, and each obtained waveform data is updated and displayed on the display screen of the display unit 4. . At this time, the control unit 6 displays the intersections of the signal waveforms A and B and the trace cursor C based on the actually measured portions of the signal waveforms A and B (actually sampled waveform data D1 and D2). The waveform data when the signal waveform B and the trace cursor C are located at the part displayed by interpolation display processing between the data of the signal waveform data D2. The data is displayed differently from the display form. In this example, as shown in FIGS. 2 and 3, as an example, the control unit 6 displays the waveform data display Da on the display unit 4 in a display form without parentheses in the former case, and in the latter case, The waveform data display Db is displayed in a display form with parentheses. As a result, the waveform data of the signal waveforms A and B (the waveform data of the signal waveforms A and B specified by the trace cursor C) at the intersection with the trace cursor C are actually measured (actually sampled) waveforms. The data D1, D2 or the interpolated information is displayed on the display unit 4 in a clearly distinguishable state.

  Specifically, in FIG. 2, for the signal waveform A, since the intersection with the trace cursor C is located at the actually measured part displayed based on the tenth sampled waveform data D1, the control unit 6 Causes the waveform data display Da of “−5 mV” to be displayed on the display unit 4 without parentheses for the waveform data D1 for this intersection. For the signal waveform B, since the intersection with the trace cursor C is located at the part displayed by the interpolation display process using the second and third sampled waveform data D2, the control unit 6 Displays the waveform data display Db of “(−8 mV)” in parentheses on the information interpolated for this intersection on the display unit 4. On the other hand, in FIG. 3, both the signal waveforms A and B, the intersection with the trace cursor C is located at the actually measured site displayed based on the sampled waveform data D1 and D2. For this reason, the control unit 6 displays the waveform data display Da of “−2 mV” and “−7 mV” for the signal waveforms A and B without the parenthesis of the waveform data D1 and D2 at the intersection with the trace cursor C. Each is displayed on part 4.

  In the waveform display device 1, the waveform data D1 is generated for the signal waveform A by the high-speed sampling clock CL1, and the waveform data D2 is generated for the signal waveform B by the relatively low-speed sampling clock CL2. Therefore, the signal waveform A is displayed with high accuracy mainly based on the actually sampled waveform data D1. Therefore, when the operation dial of the operation unit 5 is operated and the trace cursor C is moved, the control unit 6 displays the trace cursor C so that the signal waveform A is located only at the actually measured part, and the waveform. The data display Da is displayed. As a result, in the waveform display device 1, for the signal waveform A, only the actually sampled waveform data is displayed.

  As described above, according to the waveform display device 1, the control unit 6 displays the waveform data when the intersection between the signal waveforms A and B and the trace cursor C is located at the actually measured part of the signal waveforms A and B. The display section is different from the display form of the waveform data when the intersection of each signal waveform B and the trace cursor C is located at the position displayed by performing interpolation display processing between the data of the signal waveform data D2. 4, whether or not the waveform data of the signal waveforms A and B at the intersection with the trace cursor C is actually sampled waveform data D1 and D2 simply by looking at the display form. Alternatively, it is possible to accurately and easily determine whether the information is interpolated.

  In addition, this invention is not limited to said structure. As for the signal waveform A, the example in which the control unit 6 moves and displays the trace cursor C on the display unit 4 so as to be located only at the actual measurement site is described above, but the signal waveform A is not limited thereto. For example, a selection switch (not shown) is provided in the operation unit 5 and selection data indicating the switch state of the selection switch is input to the control unit 6, so that each signal waveform A displayed on the display unit 4 is displayed. , B are selected, and the position is measured only in the measured part (for example, the part displayed based on the waveform data D1 when the signal waveform A is selected) in the selected signal waveform (for example, the signal waveform A). As described above, a configuration in which the control unit 6 moves and displays the trace cursor C on the display unit 4 may be employed. In this configuration, the trace cursor C can sequentially move the displayed actual measurement sites based on the sampled waveform data D1. Also in this configuration, for example, as shown in FIG. 2, the signal S1 is selected, and the intersection point with the trace cursor C is located at the actually measured site displayed based on the waveform data D1 sampled tenth. In this case, the control unit 6 displays the waveform data D1 for this intersection point as “−5 mV” without parentheses, and the signal waveform B with parentheses “(−8 mV)” in the same manner as described above. Is displayed. According to this configuration, the selected signal S1 (or S2) is actually sampled by operating the operation dial of the operation unit 5 to move and display the trace cursor C in the same manner as the above configuration. Only the waveform data D1 (or D2) can be extracted and displayed on the display unit 4.

  In the above configuration, the two A / D conversion units 2 and 3 are provided, and the two signal waveforms S1 and S2 are sampled at different sampling periods and displayed on the display unit 4 at the same time. The number of conversion units is arbitrary, and a configuration in which three or more A / D conversion units are provided and three or more signal waveforms are simultaneously displayed on the display unit 4 may be employed. Further, the description has been given of the configuration in which the information interpolated at the intersection in the signal waveform B is displayed in parentheses on the display unit 4 when the intersection between the signal waveform B and the trace cursor C is complemented and displayed. However, instead of displaying the interpolated information at the intersection, a configuration in which the waveform data D2 closest to the intersection in the signal waveform B can be displayed, or a waveform immediately before and / or immediately after the intersection. Either of the data D2 can be displayed. In addition, the example of changing the display form depending on the presence or absence of parentheses for waveform data has been explained, but the font type of the numbers and characters that display waveform data can be changed, and the font size can be changed. You can change the display form in various ways, such as changing the presence or absence of font decorations (italics, bold, underline, upper line, etc.), changing the type of font decoration, changing the brightness of the font, etc. it can.

2 is a block diagram showing a configuration of a waveform display device 1. FIG. It is a display screen figure which shows each signal waveform A, B displayed on the display screen of the display part 4, and the trace cursor C (when the trace cursor C is located on the waveform data D1). It is a display screen figure which shows each signal waveform A, B displayed on the display screen of the display part 4, and the trace cursor C (when the trace cursor C is located on the waveform data D1, D2).

Explanation of symbols

1 Waveform display device A, B Signal waveform C Trace cursor D1, D2 Waveform data S1, S2 signal

Claims (2)

Based on signal waveform data obtained by sampling a plurality of signals at different periods, each signal waveform of the plurality of signals is displayed on a display unit together with a trace cursor, and each signal waveform, the trace cursor, A waveform display device that displays each intersection information of each signal waveform at each intersection on the display unit,
When each intersection point is located at a portion displayed based on the signal waveform data in each signal waveform, and when each intersection point is located at a portion displayed by interpolating between the signal waveform data A waveform display device for displaying each intersection information so that the display form differs from each other.   The waveform display apparatus according to claim 1, wherein the trace cursor is moved and displayed so as to be located only at a portion based on the signal waveform data in a selected signal waveform among the plurality of signal waveforms.

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