Alternate triggering in digital oscilloscopes

摘要

A digital storage oscilloscope includes a source of two or more input signals and a display device. An alternate triggering mechanism includes a selector for selecting one of the input signals. A trigger circuit is responsive to the selected input signal, and generates a trigger signal when a trigger condition is satisfied. A raster signal generator includes a plurality of waveform memories each associated with a respective input signal and responsive to the trigger signal for storing data representing the selected input signal in the waveform memory associated with the selected input signal. The raster signal generator generates a raster image signal representing the selected input signal.