Abstract: A microprocessor emulation apparatus for debugging a microprocessor of an electronic system without utilizing an interrupt signal and a stop signal to temporarily stop an operation of the system. The apparatus makes the system execute a program in the apparatus for reading and modifying contents stored in the system without using of control signals from the system by exchanging buses of the system to bus means of the apparatus to produce a pseudo stopping state, whereby the pseudo stopping state does not make the system execute a stored program of the system and which provides an analysis state which causes the system to execute the program in the apparatus.

Abstract: In a method for testing for probe calibration, a square-wave signal is applied to a probe and a cyclic probe output signal resulting therefrom is compared to a reference level at a plurality of points along one cycle of the output signal. The reference signal is iteratively increased or decreased until it is less than or greater than a minimum or maximum peak magnitude of the probe output signal by a small amount. The probe is then determined to be calibrated according whether the magnitude of the output signal at each point is greater than or less than the reference level.

Abstract: An apparatus for displaying logic signals on a raster scan type display device is disclosed. A memory circuit stores a plurality of basic patterns corresponding to segments of a logic waveform. The basic patterns are selected from the memory circuit in accordance with the logic signal and are applied to an edge generator for generating an intensity control signal for varying the intensity of an electron beam generated within the raster scan type display device.