Method to Provide Added Keys for a Keyboard
Original Publication Date: 1985-Sep-01
Included in the Prior Art Database: 2005-Feb-19
A method is described which provides the IBM Personal Computer (PC) keyboard which has only 94 engraved keys on its keyboard to support text processing programs based on 96 character sets. The method employs an ASCII-to-EBCDIC translation table which both translates and substitutes PC ASCII characters to EBCDIC characters. Appended to each and every ASCII-to-EBCDIC table is a pair of characters, either NULLs or a pair of EBCDIC character values. These entries are separated from the ASCII-to-EBCDIC table and relocated to a reserved section of memory for interpreting the ALT keystrokes function. This interpretation is in the form of a non- ASCII-to-EBCDIC translation. If the NULL is produced, it is handled similarly to other NULL (undefined) key strokes, i.e., an "INVALID KEY" message is posted on the screen to the operator.