Browse Prior Art Database

Work Area Allocation on Color Graphic Memory Planes

IP.com Disclosure Number: IPCOM000039546D
Original Publication Date: 1987-Jun-01
Included in the Prior Art Database: 2005-Feb-01
Document File: 2 page(s) / 46K

Publishing Venue

IBM

Related People

Aramaki, M: AUTHOR [+2]

Abstract

This article describes a technique for using surplus areas of three color memory planes of a color graphic display system as a single work buffer. The color memory planes contain color buffer areas used for storage of color data and mapped at the same address area, and the surplus areas are combined to constitute a single work buffer which is logically continuous as viewed from a microprocessor and mapped at the same address area as that of the color buffers. In work buffer addressing mode, the microprocessor address is translated so as to access the work area of a selected color plane. This technique facilitates utilization of the fragmentary surplus areas of the color planes for graphic processing, such as line drawing. The figure shows a color graphic CRT display system which includes color memory planes 20, 30 and 40.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 52% of the total text.

Page 1 of 2

Work Area Allocation on Color Graphic Memory Planes

This article describes a technique for using surplus areas of three color memory planes of a color graphic display system as a single work buffer. The color memory planes contain color buffer areas used for storage of color data and mapped at the same address area, and the surplus areas are combined to constitute a single work buffer which is logically continuous as viewed from a microprocessor and mapped at the same address area as that of the color buffers. In work buffer addressing mode, the microprocessor address is translated so as to access the work area of a selected color plane. This technique facilitates utilization of the fragmentary surplus areas of the color planes for graphic processing, such as line drawing. The figure shows a color graphic CRT display system which includes color memory planes 20, 30 and 40. Color data for red (R), green (G) and blue (B) are respectively stored in color buffer areas 22, 32 and 42 which are mapped at the same address area. Surplus areas 24, 34 and 44 are used as work areas, and other surplus areas 26, 36 and 46 may be used for storage of control data. Data and address from microprocessor 10 are commonly applied to the color planes 20, 30 and 40. Plane selection in color buffer addressing is made by color select register 12 which is set by the microprocessor 10. In this example, the work areas 24, 34 and 44 are mapped at the same address area with X address from "1100000" to "1111111", i.e., address bits 6 and 5 = "1". The work areas, when combined, provide a memory capacity...