Patent US2602298A successfully refreshed from Google Patents.
Patent US5977933A successfully refreshed from Google Patents.
US5977933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual image computer display controller
Assignee: S3 Graphics Co Ltd
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Filing: 1996-01-11
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Granted: 1999-11-02
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Expires: 2016-01-11
Abstract
Abstract A display control system for a portable computer drives, from a single frame buffer, both a built-in flat panel (LCD type) display as well as a separate external CRT display or an NTSC/PAL television monitor. Either identical or different images may be displayed simultaneously on the CRT display or television and on the flat panel display. Independent clocking is provided to each display to enable this simultaneous display of different images as well as simultaneously display of identical images. The display control system is suitable for use with a wide variety of CRT displays and flat panel displays by means of internal programmable controls.
Inventors
- 👤 Peter J. Wicher
- 👤 Ronda L. Collier
- 👤 Sridhar Manthani
- 👤 Zudan Shi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:12
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/14; G06F3/1423; G06F3/1438; G09; G09G; G09G2340/00; G09G2340/12
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
185 words
A display control system for a computer, the computer including a single video memory having an output port providing pixel data for display, and including a flat panel display and a port for connecting a CRT or television display, the display control system comprising: a first display controller having an input port connected to the output port of the video memory, and having an output port; a digital to analog converter having an input port connected to the output port of the first display controller and having an output port connecting to the port for connecting to the CRT or television display; a second display controller having an input port connected to the output port of the video memory and having an output port; and a flat panel display interface having an input port connected to the output port of the second display controller and having an output port for connecting to the flat panel display, wherein the first display controller drives the CRT or television display and the second display controller simultaneously and independently of the first display controller drives the flat panel display.
Claim 2
Dependent Claim
185 words
A display control system for a computer, the computer including a single video memory having an output port providing pixel data for display, and including a flat panel display and a port for connecting a CRT or television display, the display control system comprising: a first display controller having an input port connected to the output port of the video memory, and having an output port; a digital to analog converter having an input port connected to the output port of the first display controller and having an output port connecting to the port for connecting to the CRT or television display; a second display controller having an input port connected to the output port of the video memory and having an output port; and a flat panel display interface having an input port connected to the output port of the second display controller and having an output port for connecting to the flat panel display, wherein the first display controller drives the CRT or television display and the second display controller simultaneously and independently of the first display controller drives the flat panel display.
Claim 3
Dependent Claim
16 words
The display control system of claim 1, wherein the first and second display controllers are identical.
Claim 4
Dependent Claim
22 words
The display control system of claim 1, wherein the input port of the first display controller is a 32 bit parallel port.
Claim 5
Dependent Claim
65 words
The display control system of claim 1, further comprising a first FIFO (first in-first out) memory connected between the input port of the first display controller and the output port of the video memory, and a second FIFO memory connected to the input port of the second display controller and, in parallel to the first FIFO memory, to the output port of the video memory.
Claim 6
Dependent Claim
33 words
The display control system of claim 1, further comprising a lookup table memory connected between the output port of the first display controller and the input port of the digital to analog converter.
Claim 7
Dependent Claim
33 words
The display control system of claim 1, further comprising a lookup table memory connected between the output port of the second display controller and the input port of the flat panel display interface.
Claim 8
Dependent Claim
22 words
The display control system of claim 1, wherein the digital to analog converter is a random access memory digital to analog converter.
Claim 9
Dependent Claim
35 words
The display control system of claim 5, further comprising a video keyer having an output port selectively connected to the input port of the first lookup table memory and having at least one input port.
Claim 10
Dependent Claim
22 words
The display control system of claim 8, wherein the input port of the keyer is connected to a source of graphics data.
Claim 11
Dependent Claim
49 words
The display control system of claim 1, wherein the flat panel display interface input port has two portions, a first portion for receiving data for an upper portion of the flat panel display, and a second portion for receiving data for a lower portion of the flat panel display.
Claim 12
Dependent Claim
50 words
The display control system of claim 1, further comprising a clock generation circuit providing at least two clock signals of different frequency, a first of the clock signals being provided to the CRT or television display and a second of the clock signals being provided to the flat panel display.
Claim 13
Dependent Claim
34 words
The display control system of claim 1, wherein the single video memory provides a first image data set to the first display controller and a second differing image set to the second display controller.
Claim 14
Dependent Claim
29 words
The display control system of claim 1, wherein at least the second display controller outputs on its output port to the flat panel display a standard VGA video signal.
Claim 15
Dependent Claim
24 words
The display control system of claim 1, wherein at least the first display controller outputs on its output port a standard VGA video signal.
Claim 16
Dependent Claim
20 words
The display controller of claim 1, wherein the port connecting to the CRT or television display outputs a television signal.
Claim 17
Dependent Claim
54 words
The display controller of claim 1, wherein the first display controller programmably provides a video signal having a first pixel clock frequency and the second display controller programmably provides a video signal having a second different pixel clock frequency, thereby enabling independent operation of the flat panel display and the CRT or television display.
Claim 18
Dependent Claim
37 words
The display controller of claim 1, wherein the first display controller programmably provides a video signal having a first refresh rate and the second display controller programmably provides a video signal having a second different refresh rate.
Claim 19
Dependent Claim
37 words
The display controller of claim 1, wherein the first display controller programmably provides a video signal having a first screen resolution and the second display controller programmably provides a video signal having a second different screen resolution.
Claim 20
Dependent Claim
59 words
The display controller of claim 1, further comprising: a first lookup table memory connected between the output port of the first display controller and the input port of the digital to analog converter; and a second lookup table memory connected between the output port of the second display controller and the input port of the flat panel display interface.
Claim 21
Dependent Claim
41 words
The display control system of claim 1, further comprising, in each of the first and second display controllers, a cursor input terminal for receiving a cursor signal for display on respectively the CRT or television display and the flat panel display.
Claim 22
Dependent Claim
41 words
The display control system of claim 1, further comprising, in each of the first and second display controllers, an icon input terminal for receiving an icon signal for display on respectively the CRT or television display and the flat panel display.
Claim 23
Dependent Claim
38 words
The display control system of claim 1, wherein the first and second display controller each programmably support a different number of bits per pixel for display on respectively the CRT or television display and the flat panel display.
Claim 24
Dependent Claim
42 words
The display control system of claims 8, wherein a first video path including the first display controller and the video keyer and a second video path including the second display controller each support a different number of bits per pixel for display.
Claim 25
Dependent Claim
36 words
The display control system of claim 1, wherein the first and second display controllers are respectively connected independently to the port for connecting to the CRT or television display and to the flat panel display interface.
Claim 26
Dependent Claim
18 words
The display controller of claim 1, wherein the first and second display controllers output identical types of signals.
Claim 27
Dependent Claim
56 words
The display control system of claim 1, wherein the first and second display controllers generate addresses for addressing the video memory and the first display controller generates display and timing signals for control of the CRT or television display and the second display controller generates display and timing signals for control of the flat panel display.
Claim 28
Independent Claim
133 words
A method of operating a computer system having a single video memory, a CRT or television display, and a flat panel display, each of the CRT or television display and the flat panel display having an associated display controller connected to the single video memory, the method comprising: providing a first image data set to a first display controller associated with the CRT or television display from the video memory; and providing a second image data set to a second display controller associated with the flat panel display from video memory, wherein the first image data set differs from the second image data set, wherein the first display controller drives the CRT or television display and the second display controller simultaneously and independently of the first display controller drives the flat panel display.
Claim 29
Independent Claim
133 words
A method of operating a computer system having a single video memory, a CRT or television display, and a flat panel display, each of the CRT or television display and the flat panel display having an associated display controller connected to the single video memory, the method comprising: providing a first image data set to a first display controller associated with the CRT or television display from the video memory; and providing a second image data set to a second display controller associated with the flat panel display from video memory, wherein the first image data set differs from the second image data set, wherein the first display controller drives the CRT or television display and the second display controller simultaneously and independently of the first display controller drives the flat panel display.
Claim 30
Dependent Claim
28 words
The method of claim 27, wherein the first and second display controllers are respectively connected independently to the CRT or television display and to the flat panel display.
Claim 31
Dependent Claim
17 words
The method of claim 27, wherein the first and second display controllers output identical types of signals.
Claim 32
Dependent Claim
55 words
The method of claim 27, further comprising: the first and second display controllers generating addresses for addressing the single video memory; the first display controller generating display and timing signals for control of the CRT or television display; and the second display controller generating display and timing signals for control of the flat panel display.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-11-01 | 2003-05-03 | 2003-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-01 | 2007-05-03 | 2007-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-11-01 | 2011-05-03 | 2011-11-02 | $7700.00 | Window Closed / Lapsed |