Browse Prior Art Database

Software Method for Extending Cursor Speed Settings

IP.com Disclosure Number: IPCOM000114323D
Original Publication Date: 1994-Dec-01
Included in the Prior Art Database: 2005-Mar-28
Document File: 2 page(s) / 45K

Publishing Venue

IBM

Related People

Mueller, TR: AUTHOR

Abstract

Disclosed is a software method for generating additional keyboard scan codes, which are used, together with the scan codes generated by keyboard hardware, to determine the rate at which a cursor is moved.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 65% of the total text.

Software Method for Extending Cursor Speed Settings

      Disclosed is a software method for generating additional
keyboard scan codes, which are used, together with the scan codes
generated by keyboard hardware, to determine the rate at which a
cursor is moved.

      The speed of cursor movement is determined by the rate at which
scan codes are received by the Keyboard Device Driver (KBD DD).
These scan codes are 1-byte values telling the KBD DD which key has
been depressed.  When a keyboard key has been depressed for a length
of time longer than the period known as the typematic delay, the
production of scan codes at a typematic rate begins.  The maximum
level to which this rate may be set is determined by the computer
hardware, with IBM personal computer hardware, for example, being
capable of adjustment of a maximum typematic rate of 30 characters
per second (cps).

      As these scan codes stream into the KBD DD, they are placed
into the keyboard buffer, from which they are read by the application
program to be acted upon.  In this way, the rate of cursor movement
is determined by speed at which scan codes are generated.  In the
case of some applications and of some users, even the maximum level
of this rate, as determined by hardware considerations, is too slow,
hindering the performance of the application.  While it is possible
for the application to further manipulate the cursor speed, most
applications do not do this.

      On the other hand...