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Keyboard Shutout During Loading of a System in a Personal Computer

IP.com Disclosure Number: IPCOM000040450D
Original Publication Date: 1987-Nov-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 2 page(s) / 13K

Publishing Venue

IBM

Related People

Bertram, RL: AUTHOR [+2]

Abstract

When an AUTOEXEC.BAT file is loading a software system in a random- access memory (RAM) of a Personal Computer (PC) after a power-on reset (POR), the keyboard is disabled as early as possible in the loading sequence to prevent an operator from breaking out of the loading procedure of the AUTOEXEC.BAT file as could occur by pressing the right keys at the right times. It is desired to hide DOS from an operator of a PC. This includes replacing the technical messages and prompts of DOS by more user- friendly interfaces. Since it requires about one minute to load a software system in the RAM of the PC after a POR, the operator might become impatient or confused during this time and attempt to use the keyboard even though there is a message of "please stand by" on the screen with the logo.

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Keyboard Shutout During Loading of a System in a Personal Computer

When an AUTOEXEC.BAT file is loading a software system in a random- access memory (RAM) of a Personal Computer (PC) after a power-on reset (POR), the keyboard is disabled as early as possible in the loading sequence to prevent an operator from breaking out of the loading procedure of the AUTOEXEC.BAT file as could occur by pressing the right keys at the right times. It is desired to hide DOS from an operator of a PC. This includes replacing the technical messages and prompts of DOS by more user- friendly interfaces. Since it requires about one minute to load a software system in the RAM of the PC after a POR, the operator might become impatient or confused during this time and attempt to use the keyboard even though there is a message of "please stand by" on the screen with the logo. Activation of the keys of the keyboard by the operator could cause lock up of the machine or break out of the AUTOEXEC.BAT file loading procedure by pressing the Ctrl and Break keys simultaneously and enter the DOS environment or the key strokes of the activated keys to be stored in the Basic Input Output System (BIOS) keyboard buffer in the PC and begin to play out when Main Menu appears after loading is completed to cause unpredictable results. Each of these is avoided when the keyboard is completely disabled during software system loading. A logo device driver, which displays a logo screen on the PC monitor and is the first device driver installed in a memory of the RAM of the PC, is used to disable the keyboard as early in the loading sequence as possible. The logo device driver issues a command to the interrupt controller in the PC to disable the keyboard. This causes all subsequent key strokes to be stored in the keyboard buffer of the keyboard and insures that the AUTOEXEC.BAT file will not be interrupted by keys pressed between the time that the logo device driver issues its command to disable the keyboard and the time that the keyboard is enabled agai...