DIGITAL OSCILLOSCOPE, AND METHOD FOR EXPRESSING TIME-VARYING WAVEFORM BY OSCILLOGRAPH

摘要

PROBLEM TO BE SOLVED: To obtain an oscilloscope for avoiding the display of old data by writing a time mark at each collecting record. ;SOLUTION: The amplitude of a time-varying waveform is sampled at the time determined by a sample clock 4, and a row of digital amplitude values is generated. Then, a row of digital amplitude values is stored at a circulation input buffer 6 where the oldest digital amplitude value is overwritten by the most recent digital amplitude value to be stored. Then, when a selected waveform feature is generated, a trigger signal is generated from the time- varying waveform. Then, a time interval between the start of the trigger signal and the time point of a sample clock that is adjacent in terms of time is measured as a trigger offset value. And, a time mark value for indicating when the trigger signal is generated from the time-varying waveform is generated along a time axis that is extended over the predicted maximum time length when an oscillograph expression example is required. A time mark value is stored in a collecting memory 14 that stores a plurality of collecting precords as records 14a-14c....;COPYRIGHT: (C)1998,JPO