Patent ID: 6404422
Filing Date: 2002-06-11
Classification: G06F,G09G

Abstract:
An apparatus for automatically controlling a screen status of a liquid crystal display associated with a computer main body, said apparatus comprising:PLL circuit means for converting a frequency of sampling clock signals in response to externally inputted control signals; A/D converting means for converting analogue video signals of a computer main body to digital video signals in response to the sampling clock signals of said PLL circuit means; graphic control means for scaling the digital video signals of said A/D converting means in response to further externally inputted control signals so as to display picture signals on a display panel; data generating means for receiving the digital video signals from said A/D converting means, for calculating differences between adjacent digital video signals, and for summing the differences thus calculated, so as to form comparison data; and microcomputer means for outputting control signals to convert the frequency of the sampling clock signals of said PLL circuit means, for comparing the comparison data of said data generating means with reference data to detect a maximum value, for controlling the sampling clock signals so that they have a present frequency, and for recognizing a resolution of a video mode of said computer main body so as to control an overall system.