Browse Prior Art Database

Video/Touch Adapter Circuit with Dedicated Coprocessor

IP.com Disclosure Number: IPCOM000105638D
Original Publication Date: 1993-Aug-01
Included in the Prior Art Database: 2005-Mar-20
Document File: 2 page(s) / 73K

Publishing Venue

IBM

Related People

Kalendra, PW: AUTHOR [+2]

Abstract

Disclosed is a video/touch adapter circuit, including a dedicated coprocessor, for use with a video tablet in a point of sale terminal having several such circuits and tablets. The circuit can be operated in a compatibility mode, in which programs written for a system, such as the IBM 4659 Point of Sale Terminal, without the coprocessor feature, can be used without modification. The circuit can alternately be used in an extended mode, with new application software taking particular advantage of the coprocessor.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Video/Touch Adapter Circuit with Dedicated Coprocessor

      Disclosed is a video/touch adapter circuit, including a
dedicated coprocessor, for use with a video tablet in a point of sale
terminal having several such circuits and tablets.  The circuit can
be operated in a compatibility mode, in which programs written for a
system, such as the IBM 4659 Point of Sale Terminal, without the
coprocessor feature, can be used without modification.  The circuit
can alternately be used in an extended mode, with new application
software taking particular advantage of the coprocessor.

      Referring to the Figure, a point of sale terminal with a
central processor 1 includes a number of video/touch adapter cards 2,
each of which is connected to a touch sensitive video tablet (not
shown) by means of lines 3.  Touch inputs are used to provide data
from the user of the system.  The mode of the circuit is determined
by the contents of mode register 4, to which data is written by the
application program.  In the compatibility mode, mode register 4
produces an output to logic circuit 5 which places video RAM memory
6, video controller 7, and touch controller 8 under the control of
central processor 1.

      When mode register 4 is programmed by the application software
to enter the extended mode, the output of this register causes logic
circuit 5 to place video RAM memory 6, video controller 7, and touch
controller 8 under the control of coprocessor 9, which is dedicated
to the tasks of updating a single video screen and of processing user
touch input from that screen only.

      When coprocessor 9 has control of these I/O devices,
communication between central processor 1 and coprocessor 9 ca...