Bit mapped color cursor
US5146211A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 10, 1990 |
| Grant date | Sep 8, 1992 |
| Priority date | — |
| Expiry date | Aug 10, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/08
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An architecture for generating a hardware cursor in the context of a bit mapped video display system operable from a frame buffer with non-displayed but addressable memory space. A segment of the non-displayed memory is loaded with cursor information controlling the generation of its outline and its color pattern. When accessed, this cursor control data is accessed from the non-displayed segment of the memory during each horizontal blank time preceding the raster scan of the video pattern data subject to cursor overlay. Location of the cursor within the video display is determined by a group of position registers which are loaded by the CPU with cursor position data during the vertical blank time. The position registers in conjunction with a group of counters coordinate the insertion of the cursor data into a byte stream of display data as it makes its way to the CRT screen. This display data is stored in the frame buffer and is transferred to the pixel output buffer. The display data in the pixel output buffer is subsequently interpreted into colors and intensities, and displayed on the CRT screen using known techniques. The vertical and horizontal locations of the cursor are sync…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.