Browse Prior Art Database

Method to Implement Color Masks in Personal Computer Registers

IP.com Disclosure Number: IPCOM000038693D
Original Publication Date: 1987-Feb-01
Included in the Prior Art Database: 2005-Jan-31
Document File: 3 page(s) / 15K

Publishing Venue

IBM

Related People

Bezviner, DE: AUTHOR [+4]

Abstract

A method is described to fit character and screen information into a limited number of Personal Computer (PC) registers for fast execution. The Online Presentation Control Language (OPCL) is a programming language designed to create stand-alone online presentations. An information developer (typically a non-programmer) uses the OPCL's commands to specify Online Presentation structure, displayable text, sounds, animation, and other parts of the presentation. The Online Presentation Development System (OPDS) is a group of programs designed to create stand-alone online presentations. Online presentations include such items as product demonstrations, tutorials, and other programs in which the computer is used to present information.

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Method to Implement Color Masks in Personal Computer Registers

A method is described to fit character and screen information into a limited number of Personal Computer (PC) registers for fast execution. The Online Presentation Control Language (OPCL) is a programming language designed to create stand-alone online presentations. An information developer (typically a non-programmer) uses the OPCL's commands to specify Online Presentation structure, displayable text, sounds, animation, and other parts of the presentation. The Online Presentation Development System (OPDS) is a group of programs designed to create stand-alone online presentations. Online presentations include such items as product demonstrations, tutorials, and other programs in which the computer is used to present information. The OPDS consists of three tools: - The OP Compiler - converts the OPCL into object

format.

- The OP Compressor - formats and compresses

displayable picture elements of text and graphic

shapes.

- The OP Processor - loads and executes the object

code with its corresponding picture elements. A critical factor in displaying information on the screen is speed. Processing on a PC family machine is fastest when all information needed is in registers, and there are a limited number of registers. For displaying characters with various attributes in various modes, the following information was needed: - the character

- horizontal position

- vertical position

- reverse video currently on/off

- underline currently on/off

- turn on video after this char?

- turn on underline after this char?

- video mode

- for 80x25 mode, color attributes

- for 80x25 mode, save attributes when underline

active (underline, in 80x25 mode, is implemented

by the PC by changing the colors)

- for 320 mode, need 2 bytes for the expanded

character

- for 320 mode, if character data, then need

foreground color The information was distributed as follows: One group of registers is used for screen data and may be changed as the characters change. These registers are AX and BX. AX holds the character, and BX holds the masks for color, underline, reverse video, and temporary attributes. Another group of registers is positional and is used to calculate where the character will be placed in the display refresh buffer. These registers change with each character. CX holds the column offset in the display refresh buffer, and DL holds the row offset. The other register, DH, holds information related to the state of the character being displayed and

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the state of the display unit as a whole. The state relates to reverse video and underline, both can be in effect. All of this information is stored in the display unit which is read from disk at the beginning of a section in an OPDS. As each panel is displayed, the attributes f...