Browse Prior Art Database

Keyboard Controllable Device

IP.com Disclosure Number: IPCOM000081804D
Original Publication Date: 1974-Aug-01
Included in the Prior Art Database: 2005-Feb-28
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Lilie, MI: AUTHOR [+2]

Abstract

In the use of keyboard terminal systems to provide display terminal support to computing facilities, there is quite often encountered the problem that the computing facilities support half-duplex communications whereas the terminals function in the full-duplex mode.

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Keyboard Controllable Device

In the use of keyboard terminal systems to provide display terminal support to computing facilities, there is quite often encountered the problem that the computing facilities support half-duplex communications whereas the terminals function in the full-duplex mode.

Since it is imperative when using display devices coupled to interactive systems to be able to maintain communication synchronization displayed content integrity, it is necessary to render the terminals capable of functioning in the half- duplex mode. In this connection, it is to be realized that a display screen has only a limited capacity of presenting information, either because of buffer space or density of information as measured against legibility and comprehension.

In the device described herein two additional decode functions are provided for the normally full-duplex mode operating terminal. One function is operative to prevent any keyboard data from entering the multiplexor circuits of the terminal, thereby providing a keyboard lock feature.

The second function enables keyboard data to enter the multiplexor circuits of the terminal, and thereby provides an unlock function.

In addition, there may be included in the device an additional line for activating or deactivating a light indicator, to indicate when the terminal user would know that the system was soliciting input therefrom.

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