Browse Prior Art Database

Keyboard Switch Algorithm for Accessing Home and Extension Keys From the Prompt Line

IP.com Disclosure Number: IPCOM000059747D
Original Publication Date: 1986-Jan-01
Included in the Prior Art Database: 2005-Mar-08
Document File: 2 page(s) / 31K

Publishing Venue

IBM

Related People

Copenhave, MA: AUTHOR

Abstract

In the Displaywrite 3 text processing program for the IBM Personal Computer, the Prompt function can accept characters from the keyboard extension set by an enhancement to its L3P datastream management capability described as follows: 1. A keyboard mode switch indicating the current keyboard mode (either home or extension) is implemented as a toggle flag. 2. The keyboard mode is set or reset each time a switch is detected between keyboards; a keyboard switch occurs each time the operator types a key from a keyboard different from the last key typed. 3. For each keyboard switch, an L3P Graphic Character Set Global identification multi-byte control (SCG) is inserted into the input buffer prior to the current keystroke.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 2

Keyboard Switch Algorithm for Accessing Home and Extension Keys From the Prompt Line

In the Displaywrite 3 text processing program for the IBM Personal Computer, the Prompt function can accept characters from the keyboard extension set by an enhancement to its L3P datastream management capability described as follows:
1. A keyboard mode switch indicating the current keyboard mode (either home or extension) is implemented as a toggle flag. 2. The keyboard mode is set or reset each time a switch is detected between keyboards; a keyboard switch occurs each time the operator types a key from a keyboard different from the last key typed. 3. For each keyboard switch, an L3P Graphic Character Set Global identification multi-byte control (SCG) is inserted into the input buffer prior to the current keystroke. This switch algorithm shown in the figure also conserves input buffer space by "remembering" the current keyboard mode via the keyboard-type toggle. Thus, the 8-byte SCG control is inserted into the datastream only when a change is detected from one keyboard mode to another.

1

Page 2 of 2

2

[This page contains 3 pictures or other non-text objects]