Flat touch screen workpad for a data processing system

• US 5,528,266 A
• Filed: 06/08/1993
• Issued: 06/18/1996
• Est. Priority Date: 05/15/1989
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Donaldson, Robert L., Tannenbaum, Alan R., Stein, Frank L., Arbeitman, Gordon W.
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): NGUYEN, CHANH DUY
• Application Number:
  US08/073,261
• Time in Patent Office: 1,106 Days
• Field of Search: 340/706, 340/710, 340/711, 340/712, 340/784, 341/33, 341/34, 364/709.01, 364/709.02, 364/709.12, 178/18, 178/19, 178/20, 345/173, 345/179, 345/182, 345/174, 345/175, 345/156
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers

Abstract

Improvements in the art of sensor and display technology now make the implementation of a workpad concept feasible. While prior art touch displays are acceptable for short, casual use tasks, they may not be feasible or suited for intensive use tasks. Recent improvements in the optical qualities (brightness, contrast, viewing cone) of flat panel displays, such as LCDs, allow implementing a touch screen for use in a horizontal orientation. This greatly improves the human factors for applications involving extensive pointing, drawing, or writing.

Claims

1. In a data processing system, a workpad connected to a computer, the workpad including a touch sensor activated via an electrically operated stylus and a finger actuated control button, the improvement comprising:

a RAM coupled to the computer for storing up to four (4) frames of data;

a first multiplexer coupled to the RAM for receiving and sending control/data signals to a display in the workpad;

a first demultiplexer coupled to the display for receiving and applying the control/data signals to the display;

a second multiplexer in said workpad coupled to said display and to said computer, said second multiplexer having a first input connected to said tough sensor and a second input connected to said control button, for sequentially ordering signals output from said touch sensor and from said button in an order of occurrence of said touch sensor signals and said button signals, and delivering said ordered signals to said computer; and

a second demultiplexer in said computer for receiving said sequential signals from said second multiplexer to detect whether said button signal occurred before said touch signal.

2. The data processing system of claim 1 further including a plurality of finger actuated control buttons, each button electrically coupled to a change of state register and a button state register;

a memory containing stored programs for interpreting the state of the button state register; and

means for using the stored programs to emulate a variety of types of inputs from the workpad.

3. The data processing system of claim 2 wherein actuation of a control button generates a code identifying the control button which was actuated and initiates an interrupt signal to the computer to activate an interrupt handling routine which will query the state of the button state registers to identify the button which was actuated.

4. The data processing system of claim 1 wherein the finger control buttons can emulate a mouse pointing device under control of the stored programs.

5. The data processing system of claim 1 wherein the finger control buttons can emulate a function key under control of the stored programs.

6. The data processing system of claim 1 wherein the finger control button is mounted on the workpad to be actuated by one hand of a user while the other hand of the user is manipulating the touch sensor.

7. In a data processing system, a workpad having an electrically operated stylus overlay and first and second finger actuated action buttons, said workpad coupled to a computer for exchanging data therebetween, the improvement comprising:

a RAM coupled to the computer for storing up to four (4) frames of data;

a first multiplexer coupled to the RAM for receiving and sending control/data signals to a display in the workpad;

a first demultiplexer coupled to the display for receiving and applying the control/data signals to the display;

a second multiplexer in said workpad coupled to said display and to said computer, said second multiplexer having a first input coupled to said first action button for receiving first button signals, a second input coupled to said second action button for receiving second button signals and a third input coupled to said stylus overlay for receiving stylus input signals;

said second multiplexer having an output for outputting said first button signals, said second button signals and said stylus input signals in order of their occurrence;

a second demultiplexer associated with said computer, having an input coupled to said output of said second multiplexer and having an output coupled to said computer, for providing to said computer said first button signals, said second button signals and said stylus input signals in said order of their occurrence; and

said computer selectively utilizing said stylus input signals in response to said order of occurrence of said stylus input signals with respect to the occurrence of said first and second button signals.

8. In a data processing system having a workpad with a touch overlay actuated via an electrically operated stylus and first and second finger actuated action buttons, said workpad coupled to a computer for exchanging data therebetween, the method comprising:

storing up to four frames (4) of data in a RAM coupled to the computer;

combining control signals and the data in a first multiplexer coupled to the RAM;

receiving the control signals and the data in a first demultiplexer in the workpad;

applying the control signals and the data to the display;

receiving first button signals from said first action button, receiving second button signals from said second action button and receiving touch input signals from said touch overlay in a second multiplexer in said workpad;

outputting said first button signals, said second button signals and said touch input signals in order of their occurrence in a data stream, from said second multiplexer;

providing to said computer said first button signals, said second button signals and said touch input signals in said order of their occurrence from a second demultiplexer associated with said computer, having an input coupled to receive said data stream from said second multiplexer; and

selectively utilizing said touch input signals in said computer in response to said order of occurrence of said touch input signals with respect to the occurrence of said first and second button signals.

9. In a data processing system having a workpad actuated by an electrically operated stylus overlay and first and second finger actuated action buttons, said workpad coupled to a computer for exchanging data therebetween, the method comprising:

storing up to four frames (4) of data in a RAM coupled to the computer;

combining control signals and the data in a first multiplexer coupled to the RAM;

receiving the control signals and the data in a first demultiplexer in the workpad;

applying the control signals and the data to the display;

receiving first button signals from said first action button, receiving said second button signals from said second action button and receiving stylus input signals from said stylus overlay in a second multiplexer in said workpad;

outputting said first button signals, said second button signals and said stylus input signals in an order of their occurrence in a data stream, from said second multiplexer;

providing to said computer said first button signals, said second button signals and said stylus input signals in said order of their occurrence from a second demultiplexer associated with said computer, having an input coupled to receive said data stream from said multiplexer; and

selectively utilizing said stylus input signals in said computer in response to said order of occurrence of said stylus input signals with respect to the occurrence of said first and second button signals.