method for displaying a waveform of at least one input signal and attributinformationen in the screen of a cathode ray tube of an oscilloscope and an oscilloscope on the application of the procedure.

摘要

Method for displaying a waveform of at least one input signal and attribute information on a screen of a cathode ray tube of an oscilloscope, in which suitable deflection signals and an intensity modulation signal for an electron beam of the tube are generated and delivered to the tube. The method comprises transferring coordinate data of dots, to be displayed, of a waveform of at least one input signal from an acquisition memory (18) to a processor memory (8) which is connected to a bus structure (4) of a microprocessor system. Stored in the processor memory are also coordinate data of attribute information dots to be displayed, as well as a display program for the microprocessor system which depends on a desired composition of an image on the screen and on a desired display sequence of dots of the image. Depending on the program, selected coordinate data of points to be displayed are selected from the processor memory and transferred by means of direct memory access (DMA) from the processor memory to a first-in-first-out (FIFO) display memory (30). For each selected coordinate datum, the program determines a display control datum which is stored together with the coordinate datum in the display memory. The transfer to the display memory is continuously repeated but is postponed if and for as long as the display memory has reached a predetermined degree of occupation thereof. The control datum read out of the display memory together with the coordinate datum determines the selection of the deflection signals and the modulation signal. The coordinate data of the at least one waveform are also transferred by means of direct memory access (DMA) from an acquisition memory to the processor memory. IMAGE IMAGE