Method to Provide Extra Dead Keys on an IBM PC Keyboard
Original Publication Date: 1985-Sep-01
Included in the Prior Art Database: 2005-Feb-19
A method is described to provide more keys on the keyboard of an IBM Personal Computer than normally is encoded in the Basic Input-Output System (BIOS) of the IBM Personal Computer (PC). The keyboard program for the IBM Displaywriter system is able to recognize and compress dead key sequences. The Displaywriter keyboard and the 96 EBCDIC characters of the word processor (WP) keyboard can be emulated on an IBM PC keyboard by matching or superimposing the PC and WP dead key definitions. A method to add dead keys is described in which six additional byte positions are added to each National Language ASCII-to-EBCDIC translation table. These positions contain up to 6 optional dead key characters encoded in one of the 96 EBCDIC characters of the WP character sets.