Computer graphics processing and selective visual display system – Display driving control circuitry – Display power source
Patent
1993-06-23
1996-01-30
Hjerpe, Richard
Computer graphics processing and selective visual display system
Display driving control circuitry
Display power source
345199, G09G 506
Patent
active
054883938
ABSTRACT:
A graphics subsystem, including a video digital-to-analog converter, is disclosed. A high speed oscillator generates a pixel clock signal at the frequency at which pixels are to be displayed. Included in the video DAC is a frequency divider which presents an output clock signal having a period which is a multiple of the pixel clock signal, the multiple corresponding to the level of multiplexing of pixel data to be provided by the video DAC; this multiple can equal unity. The video controller in the system receives the output clock signal, and generates clock signals to control the serial port of the frame memory, and also to control the latching of the first stage in the video DAC. The first stage latch in the video DAC latches in the multiple pixel data from the frame memory, and the multiplexer in the video DAC presents the data to the color palette RAM, or around the color palette RAM in true-color non-multiplexed mode, according to the pixel clock signal. As a result, the pixel clock rate is not dependent by the propagation delay of the output clock signal through the video controller, and higher speed system operation is achieved.
REFERENCES:
patent: 4364037 (1982-12-01), Walker
patent: 4635048 (1987-01-01), Nishi et al.
patent: 4660070 (1987-04-01), Nishi et al.
patent: 4688032 (1987-08-01), Saito et al.
patent: 4872002 (1989-10-01), Stewart et al.
patent: 4918436 (1990-04-01), Johary
Product Selection Guide (Brooktree Corporation, 1991), pp. 13-14.
Bounds Brian F.
Wood Paul B.
Compaq Computer Corporation
Hjerpe Richard
Wu Xiao M.
LandOfFree
High-speed video display system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with High-speed video display system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High-speed video display system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-159073