Patent ID: 6297794
Filing Date: 2001-10-02
Classification: G06F,G09G,H04L,H04N

Abstract:
A computer system comprising:a video port for receiving motion-picture data;a display controller capable of displaying the motion-picture data input to the video port;a motion-picture dedicated bus for transferring motion-picture data to a video port of the display controller; anda plurality of video devices for processing different motion-picture sources, respectively, each having an output port which is connected to said motion-picture dedicated bus and from which motion-picture data is output to said motion-picture dedicated bus,said motion-picture dedicated bus including a control signal line which is connected in common to said plurality of video devices which is set into an active state by the video device requesting for use of said motion-picture dedicated bus,each of said video devices comprising:an output buffer for outputting motion-picture data from said output port to said motion-picture dedicated bus;means for setting said signal control line in an active state for a predetermined time, in accordance with a motion-picture data transfer instruction issued from said CPU, and for allowing said output buffer to output the motion-picture data, after said predetermined time has elapsed; andmeans for monitoring the state of said control signal line and prohibiting said output buffer from outputting motion-picture data while said control signal remains active,whereby the video device set into an active state most recently is allowed to use the motion-picture data dedicated bus.