Browse Prior Art Database

BIOS Font Changer for 640 PELS Width Flat Panel Display

IP.com Disclosure Number: IPCOM000104721D
Original Publication Date: 1993-May-01
Included in the Prior Art Database: 2005-Mar-19
Document File: 2 page(s) / 43K

Publishing Venue

IBM

Related People

Kato, N: AUTHOR [+3]

Abstract

A program is disclosed that prevents adjacent characters on screen from touching each other, when a 640 pel width flat panel monitor device such as a liquid crystal display is connected to the conventional analog video port of the Video Graphics Array in an IBM Personal Computer compatible system.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

BIOS Font Changer for 640 PELS Width Flat Panel Display

      A program is disclosed that prevents adjacent characters on
screen from touching each other, when a 640 pel width flat panel
monitor device such as a liquid crystal display is connected to the
conventional analog video port of the Video Graphics Array in an IBM
Personal Computer compatible system.

      As illustrated in symbol *1 of the figure, use of the existing
9 x 16 or 9 x 14 dot font pattern in the system ROM (read-only
memory) can cause characters such as 'M' to touch each other on
screen.  The disclosed program replaces the data, which is stored in
what is called Shadow RAM, which specifies 9 x 16 and 9 x 14 dot font
pattern with that of 8 x 16 and 8 x 14 dot font pattern respectively.
Replacing the font pattern data is accomplished by enabling write
operation to the Shadow RAM, which normally contains a copy of the
system ROM and is write protected to emulate ROM, and copying 8 x 16
and 8 x 14 dot font pattern in the ROM over the 9 x 16 and 9 x 14 dot
font pattern in the Shadow RAM.  This results in characters separated
by at least one dot, as illustrated in a symbol *2 of the Figure.
This method has the advantage of not requiring modification to the
system ROM nor programs that make use of the 9x16 and 9 x 14 dot font
pattern.