High sweep rate waveform display control for digital recording waveform

Abstract

A digital waveform measuring and display oscilloscope includes a digital memory which stores one full screen of waveform data. The analog waveform is sampled, digitized and placed in memory at a user selected mode and sampling rate. A data acquisition mode control permits the user to select a continuous mode in which a live waveform is displayed moving from the right to the left on the screen. A hold mode is provided in which a preceding full screen data array is captured in the memory and displayed as a static display. A trigger mode is also provided with a variable delay, related to multiples of a full screen array, in which one full screen array is captured in relation to a trigger event and displayed as a static display. A particularly unique Periodic Hold mode creates a cyclical sequence which includes data acquisition and simultaneous display blanking which is terminated in response to a trigger signal sequence. The captured data is displayed for a short time and is followed by an automatic signal to the control system to again initiate acquisition of the waveform signal in a free running mode. As data is acquired, the trigger circuit is automatically enabled to again stop the data acquisition at or following a trigger signal. The display is blanked during each data acquisition with the previous image momentarily retained on the display screen during the blanking period. The display is a series of static displays which appear to the user essentially in the form obtained with a conventional oscilloscope.