Data processing apparatus

• US 5,396,593 A
• Filed: 02/14/1994
• Issued: 03/07/1995
• Est. Priority Date: 11/10/1989
• Status: Expired due to Term

• Current Assignee: Videocon Global Ltd. (Videocon Industries Limited)
• Original Assignee: International Business Machines Corporation
• Inventors: Mori, Masaya, Morimoto, Yutaka
• Primary Examiner(s): Nguyen, Phu K.
• Application Number:
  US08/195,610
• Time in Patent Office: 386 Days
• Field of Search: 395/162, 395/163, 395/118, 395/128, 395/164, 395/165, 395/166, 345/132, 345/205, 345/214
• US Class Current: 345/501
• CPC Class Codes: G09G 1/16 the pattern of rectangular co-ordinates extending over the whole area of the screen, i.e. television type raster
• CPC Class Codes: G09G 1/167 Details of the interface to the display terminal specific for a CRT details suitable for both CRT and flat panel G09G5/006, specific for a flat panel G09G3/2096
• CPC Class Codes: G09G 1/285 Interfacing with colour displays, e.g. TV receiver
• CPC Class Codes: G09G 2370/04 Exchange of auxiliary data, i.e. other than image data, between monitor and graphics controller
• CPC Class Codes: G09G 2370/042 for monitor identification
• CPC Class Codes: G09G 5/006 Details of the interface to the display terminal specific for a display terminal using a CRT G09G1/167; using a flat panel G09G3/2096; circuits for interfacing with colour displays G09G5/04
• CPC Class Codes: G09G 5/04 using circuits for interfacing with colour displays

Abstract

Data processing apparatus including a display monitor operable in response to a display signal of predetermined frequency and a computer for transmitting a display signal to the display monitor. The display monitor generates an identifier signal indicating the predetermined frequency at which the display monitor operates. The computer means uses the identifier signal to determine the frequency of the display signal.

Claims

1. Data processing apparatus including:

display means operable in response to a display signal of predetermined frequency to display graphics image, said display means having at least a refresh rate and a display resolution which together define said predetermined frequency, said display means also having identifier means for generating an identifier signal indicating said predetermined frequency; and

data processing means for transmitting said display signal to said display means at a selectable transmission frequency, said data processing means having frequency deciding means for selecting said selectable transmission frequency to equal the predetermined frequency of said display signal in response to said identifier signal.

2. Apparatus as in claim 1 in which said frequency deciding means comprises:

a plurality of oscillators different in oscillation frequency from one another; and

an oscillator selecting means connected to said oscillators for selecting one of said oscillation frequencies in response to said identifier signal.

3. Apparatus as in claim 2 in which said oscillator selecting means comprises a logic gate means for selecting and outputting only one of the output signals from said plurality of oscillators in response to said identifier signal.

4. Apparatus as in claim 2 in which said oscillator selecting means includes a microprocessor.

5. Apparatus as in claim 1 in which said frequency deciding means includes latching means for latching said identifier signal.

6. A display device for a computer system comprising:

display means for generating a graphic display in response to a display signal of predetermined frequency, said display means having at least a refresh rate and a display resolution that together define said predetermined frequency; and

identifier means for generating an identifier signal indicative of said predetermined frequency.

7. A data processing system including a processor and memory for processing data and generating output in the form of a display signal at an output display signal frequency, said data processing system comprising:

means for receiving a signal indicative of a predetermined display device signal frequency, said display device signal frequency identifying at least a display resolution and display refresh rate; and

frequency deciding means for setting the output display signal frequency as the frequency received by the means for receiving.

8. The system of claim 7 in which said frequency deciding means comprises:

a plurality of oscillators different in oscillation frequency from one another; and

an oscillator selector means connected to said oscillators for selecting one of said oscillation frequencies in response to said means for receiving.

9. The system of claim 8 in which said oscillator selector means comprises:

logical gate means for selecting and outputing only one of the output signals from said plurality of oscillators in response to said means for receiving.

10. The system of claim 9 in which said oscillator selected means comprises a microprocessor.

11. The system of claim 7 in which said frequency deciding means includes latching means for latching the signal received by the means for receiving.