Microprocessor controlled monitor

• US 5,241,281 A
• Filed: 03/19/1990
• Issued: 08/31/1993
• Est. Priority Date: 03/19/1990
• Status: Expired due to Fees

• Current Assignee: Capetronic Group Ltd. (Nimble Holdings Co. Ltd.)
• Original Assignee: Capetronic Group Ltd. (Nimble Holdings Co. Ltd.)
• Inventors: Shaufl, Robert, Wilkes, Derek, Warchol, James
• Primary Examiner(s): Weldon, Ulysses
• Assistant Examiner(s): Luu, Matthew
• Application Number:
  US07/495,857
• Time in Patent Office: 1,261 Days
• Field of Search: 358/148, 358/150, 358/158, 358/139, 358/140, 358/180, 358/22, 358/10, 340/814, 340/799, 340/717, 340/731, 340/720, 340/771
• US Class Current: 345/213
• CPC Class Codes: H04N 17/04 for receivers

Abstract

A display monitor capable of providing fully synchronized image display in response to an incoming video signal having a range of possible timing formats. The monitor employs a microprocessor that discriminates between the disparate horizontal and vertical sync signals by developing a characteristic signature of the timing format and thereafter searching a resident database of different formats to discern a match. A calibration mode is provided to allow the adjustment of the monitor to an incoming signal that is otherwise unrecognized by the microprocessor or to allow the updating of previously stored information.

Claims

1. In combination in a microprocessor controlled monitor, comprising:

a. input means for receiving of a video signal having a particular timing format including horizontal and vertical timing signals for control of a raster scan based output,

b. digital random access memory means for receiving and storing a plurality of designated and distinct timing format parameters, including an addressable timing signature, at discrete memory locations,

c. said microprocessor means for calculating said timing signature based on said timing signals for said received video signal;

d. said microprocessor means for comparing the signature of the received video signal with the signatures stored in said discrete memory locations,

e. deflection control means including a horizontal DAC and a vertical DAC for receiving timing format parameters from said digital random access memory means and driving horizontal and vertical deflection yokes in response thereto, and

f. said microprocessor means in communication with said deflection control means and random access memory means capable of operating in at least two separate modes, including an operation mode characterized by comparing and loading previously stored timing format parameters for the control of said DACs for driving said deflection yokes, and a calibration mode for quantifying specific timing format parameters associated with a received video signal having a signature that does not match any stored signature values in said memory and storage of the quantified specific timing format.

2. The microprocessor controlled monitor of claim 1, wherein said timing signature is based on the horizontal and vertical scanning frequency of the received video signal.

3. The monitor of claim 1, further comprising a video control means including a video DAC for controlling the video amplifier gain.

4. The microprocessor controlled monitor of claim 1, wherein said data processor provides, in said calibration mode, selected coarse alignment values to the DACs including horizontal hold, linearity, and B+voltage, sufficient to provide a stable image on a display screen, and further, user adjustable control means for adjusting plural dimensions of said stable image on said display screen.

5. The microprocessor controlled monitor of claim 4, wherein said data processor further provides for memory storage means for storing timing format parameters associated with a stable, properly sized and positioned image resulting from said calibration mode.

6. In a microprocessor system for controlling a raster scan process on a display monitor, comprising:

video signal receiving means for reception of a composite video signal having image information and raster scan controlling sync information;

microprocessor means for determining a sync signal signature from said received video signal and comparing said signature with a plurality of stored sync signal signatures;

timing format parameter retrieval means for retrieving timing format parameters from memory means corresponding to a sync signal signature that matches said sync signal signature of said received video signal;

raster scan control means for controlling said raster scan process by applying said matching timing format parameters to horizontal and vertical deflection circuits; and

calibration means in communication with said microprocessor means for adjusting selected timing format parameters that are associated with a sync signal signature that fails to match any stored sync signal signatures, wherein said calibration means permits selected adjustment of horizontal size/width, horizontal position, vertical size/height, and vertical position associated with said raster scan process.

7. The system of claim 6, wherein said vertical and horizontal deflection circuits are modulated by discrete DACs and controlled by said matching timing format parameters.

8. The system of claim 6, wherein said calibration means further comprises the adjustment of pincushion correction, trapezoid correction, and horizontal linearity.

9. A microprocessor controlled process for synchronizing a display monitor to an incoming video signal having a range of possible horizontal scanning frequencies between about 15 KHz to about 75 KHz, comprising the steps of:

a. receiving said incoming video signal;

b. determining a timing signature associated with said incoming video signal, wherein said signature is a compilation of horizontal scan rate and vertical frame rate data;

c. comparing said determined timing signature with a plurality of stored timing signatures which designate address locations, for storing discrete timing format parameters;

d. retrieving timing format parameters associated with a stored timing signature that matches said determined timing signature;

e. applying said selected timing format parameters to control a raster scan projection of said incoming video signal; and

f. providing the capability to (i) calibrate said display monitor by adjusting selected timing format parameters, including horizontal position and width and vertical position and height, and (ii) thereafter storing the adjusted selected timing format parameters after calibration.

10. The process of claim 9 wherein said calibration step (f) includes accessing default parameters to provide a stable image on said display monitor for calibration.

11. The process of claim 9, wherein said raster scan projection is controlled by a horizontal DAC and vertical DAC that provide the resistive inputs to a horizontal deflection circuit and vertical deflection circuit, respectively.