Information
-
Patent Grant
-
6437761
-
Patent Number
6,437,761
-
Date Filed
Monday, October 27, 199727 years ago
-
Date Issued
Tuesday, August 20, 200222 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Hjerpe; Richard
- Tran; Henry N.
Agents
- Blakely, Sokoloff, Taylor & Zanman LLP
-
CPC
-
US Classifications
Field of Search
US
- 345 11
- 345 204
- 345 904
- 345 618
- 395 18221
- 395 18222
- 395 75001
- 395 75003
- 340 654
- 364 52831
- 324 555
- 324 612
- 324 771
-
International Classifications
-
Abstract
A method for storing status information prior to shutdown of a video monitor due to a failure. An indication of an operational parameter is obtained. Based on the indication, it is determined if the failure occurs warranting shutdown. If the failure occurs, status information is stored in a non-volatile memory for later retrieval during repair. A shutdown sequence is generated to disable the video monitor.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to video monitor technology. In particular, the present invention relates to status information storage and display for multi-frequency video monitor.
2. Description of Related Art
There are many causes for failure in video monitors. Examples of these causes include component aging, component and assembly defects, and incorrect usage. When the failed monitor is returned to the manufacturer for repair, it is important to determine these causes as accurately as possible.
One of the most significant clues for diagnosis of problems is the state of the monitor immediately before the failure. By examining the status information immediately prior to failure, repair personnel can quickly identify the source of failure and thus perform the repair effectively.
The prior art video monitor systems do not provide this information. Without the information, the diagnosis is prolonged and the repair becomes a tedious process.
Furthermore, some useful information about the monitor are only shown at the back of the monitor, causing access difficulty. This information may include model number, serial number, and the year of manufacturing. The monitor indication information is useful not only to the test personnel when the monitor is shipped back for repair, but also the user in the field.
Accordingly, there is a need to provide an apparatus and method for storing status information prior to failure and displaying monitor information.
SUMMARY OF THE INVENTION
The present invention discloses a method and apparatus for storing status information prior to shutdown of a video monitor. The method comprising the steps of: (1) obtaining an indication of an operational parameter; (2) determining if a shutdown condition occurs based on the indication; and (3) if the shutdown condition occurs, storing status information in a non-volatile memory, and generating a shutdown sequence to disable the video monitor.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present invention will become apparent from the following detailed description of the present invention in which:
FIG. 1
is a block diagram illustrating one embodiment of a video monitor system that operates in accordance with the teachings of the present invention.
FIG. 2
is a flow diagram illustrating one embodiment of storing status information.
FIG. 3
is a diagram illustrating a display for monitor information.
DESCRIPTION OF THE PRESENT INVENTION
The present invention discloses a method for storing status information prior to shutdown. The conditions of the video circuit are constantly monitored. When any of the conditions exceeds the allowable range, the entire set of operational parameters relating to the function of the video monitor is stored in EEPROM before shutdown.
In the following description, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that these specific details are not required in order to practice the present invention. In other instances, well known electrical structures and circuits are shown in block diagram form in order not to obscure the present invention unnecessarily.
Referring to
FIG. 1
, a block diagram illustrating one embodiment of a video monitor system
100
that operates in accordance with the teachings of the present invention is shown. The system
100
comprises a picture tube
110
, a video control circuit
130
, a video processing circuit
140
, a processor
150
, a power/shutdown control circuit
160
, a synchronization signal processor
165
, an electrically erasable programmable read only memory (EEPROM)
170
, a test/user communication interface circuit
175
, a front panel
180
, a video card
185
, and a test station
190
.
Picture tube
110
contains electron gun assembly
115
and phosphor screen
117
. Electron gun assembly
115
typically comprises three electron guns corresponding to the red, green, and blue colors. The electron guns emit electron beams that strike the corresponding phosphor to produce picture elements on the screen display.
Video control circuit
130
contains circuitry that control the beam currents and supply voltages to the electron gun assembly
115
. The video control circuit
130
also provides feedback information on the operational parameters of the video system. Four important parameters that affect the operation of the video monitor are: the automatic beam current, the high voltage level, the horizontal scan present signal, and the vertical scan present signal. The ABL is expressed as a direct current (DC) voltage which is connected to one analog input channel on the processor
150
via signal line
131
. The high voltage level is also a DC voltage connected to one analog input channel on the processor
150
via signal line
132
. The horizontal and vertical scan present signals are connected to the input port lines on the processor
150
to the synchro processor
162
.
The video processing circuit
140
performs the necessary video control functions. Examples of these control functions include generation of the beam currents, high voltage control, horizontal synchronizing signal, and vertical synchronizing signal. The video processing circuit
140
receives signals from the video card
185
, the processor
150
, and the power/shutdown control circuit
160
.
The processor
150
comprises a central processing unit (CPU)
152
, a read only memory (ROM)
154
, a random access memory (RAM)
156
, and analog-to-digital converter (ADC)
158
, a synchro processor
162
, an input/output port
164
, a communication interface
166
, and an I
2
C bus interface
168
. The processor
150
may be any microprocessor or microcontroller. In one embodiment, processor
150
is a microprocessor having part number ST7275, manufactured by SGS Thomson. The ADC converts an analog voltage to an 8-bit digital data. An analog multiplexer (not shown) is used to selects an analog input voltage from a number of analog inputs for conversion.
The power/shutdown control circuit
160
receives signal from the processor
150
to generate signal to the video processing circuit
140
. When a shutdown condition occurs, the power/shutdown control circuit
160
receives a shutdown command signal from the processor
150
. The power/shutdown control circuit
160
then proceeds to shutdown the video processing circuit
140
and other functional circuitry in the video monitor system
100
.
The synchronization signal processor
165
receives synchronizing signals from the processor
150
and provides various synchronization functions such as vertical and horizontal corrections. In one embodiment, the synchronization signal processor
165
is a processor having part number uPC1886CT manufactured by NEC Corporation in Japan.
The EEPROM
170
stores status information, monitor information, initialization information and other operational parameters. The EEPROM
170
is connected to the Inter-Integrated Circuit (I
2
C) bus interface
166
inside the processor
150
. The I
2
C bus is a serial bus for communication between the processor
150
and the EEPROM
170
.
The test/user communication interface
175
provides input/output communication to the test station
190
and the front panel
180
. The test/user communication interface
175
is connected to the communication interface
166
inside the processor
150
. The communication may be serial or parallel.
The front panel
180
provides user interface with buttons or switches. The buttons include a MENU button, and other functional buttons to control the operation of the video monitor.
The video card
185
provides video control information and signals to the video processing circuit
140
and the processor
150
. The video card
185
is usually a graphics controller card that stores graphic data and generates horizontal and vertical synchronizing signals. The video card
185
is interfaced with the user's computer system.
The test station
190
is a PC with its own monitor and keyboard. The test station communicates with the processor
150
via the test/user communication interface
175
. The test station has several modes of operation. During product adjustment, the test station
190
allows test personnel to adjust functional parameters such as the initialization data, and calibration parameters. When the product is returned for repair, the test station
190
can be used to inquire the nature of the failure. The status information stored in the EEPROM
170
can be retrieved and used by the test station
190
.
Referring to
FIG. 2
, a flow diagram illustrating a process S
200
to display monitor information and to store status information prior to shutdown is shown.
Proceeding from a START state, the process S
200
enters decision step S
210
to determine if the user changes or selects an operation mode. If NO, the process S
200
comes back decision step S
210
again. If YES, the process S
200
enters step S
220
which selects the mode table according to the user's selection. The mode table includes information regarding user's usage preferences such as frequency.
The process S
200
then enters decision step S
225
to determine if the MENU button is pressed for more than a predetermined amount of time. In one embodiment, this predetermined period is 5 seconds. If the MENU button is held down for more than 5 seconds, the process S
200
enters step S
230
to retrieve monitor information stored in ROM or EEPROM. Then the process S
200
proceeds to step S
235
to display the retrieved information on the monitor screen. The process S
200
then returns to decision step S
210
. If the MENU button is not held down for more than 5 seconds, the process S
200
enters step S
240
to perform other monitor control functions. These control functions may include processing menu items, generating synchronization signals, and communicating with user's video card
185
.
The process S
200
then enters decision step S
245
to determine if the automatic beam level (ABL) is within the allowable range. In one embodiment, the ABL is an analog voltage provided by the video control circuit
130
in FIG.
1
. This analog voltage is digitized by the analog-to-digital converter (ADC)
158
located inside the processor
150
as shown in FIG.
1
. The determination involves comparing the digitized ABL voltage with a predetermined maximum value. If the digitized ABL value exceeds this predetermined maximum value, a shutdown condition occurs, causing the process S
200
to enter step S
270
. If the digitized ABL value is less than the maximum value and above a minimum value, the process S
200
proceeds to decision step S
250
.
In the decision step S
250
, it is determined if the high voltage level is within an acceptable range. The high voltage level (HVL) is an analog voltage provided by the video control circuit
130
in FIG.
1
. This HVL is digitized by the ADC
158
. This determination is performed by comparing the digitized HVL with a predetermined HVL maximum value and a predetermined HVL minimum value. If the digitized HVL is outside this range, the process S
200
enters step S
270
to shutdown the video monitor system. If not, the process S
200
proceeds to decision step S
255
.
In the decision step S
255
, it is determined if the horizontal scan signal is present. The horizontal scan present signal is provided by the synchro processor
162
. The synchro processor receives synchronizing signals from the video card
185
and/or the video control circuit
130
. In one embodiment, the synchronizing signal comes from the video card
185
. In another embodiment, the horizontal sync signal comes from the video control circuit
130
. An absence of this signal indicates that a shutdown condition occurs and the process S
200
enters step S
270
. If the horizontal sync signal is present, the process S
200
proceeds to decision step S
260
.
In the decision step S
260
, it is determined if the vertical scan signal is present. The vertical scan present signal is provided by the synchro processor
162
. The synchro processor receives synchronizing signals from the video card
185
and/or the video control circuit
130
. In one embodiment, the synchronizing signal comes from the video card
185
. In another embodiment, the vertical sync signal comes from the video control circuit
130
. An absence of this signal indicates that a shutdown condition occurs and the process S
200
enters step S
270
. If the vertical sync signal is present, the process S
200
returns back to decision step S
210
.
In step S
270
, all monitor status information at the time the shutdown condition occurs is retrieved. This information includes the following:
User mode table
Horizontal frequency
Vertical frequency
Polarity information for horizontal and vertical frequencies
Monitor state: aging mode, phase-locked mode, sync mode.
Input synchronization: separate sync, sync on green, composite
Additional information can be retrieved.
Process S
200
proceeds to step S
280
to write the retrieved information to EEPROM This information will then be available to repair personnel for repair diagnosis when the monitor is shipped back to the manufacturer.
Process S
200
then proceeds to step S
290
to generate the shutdown sequence to the video monitor system. The shutdown essentially includes cutting off power supply to the relevant circuitry in the system. The process S
200
then terminates.
Referring to
FIG. 3
, a diagram illustrating the display
300
of the monitor information is shown. The display
300
comprises a monitor information window
310
, a front panel
320
, and a MENU button
The monitor information window
310
comprises information about the monitor such as model number serial number, and year of manufacture. This information is displayed when the user holds the MENU button
350
for more than 5 seconds. The information is displayed until the user selects other display mode. By having the information displayed at the touch of a button, the user can immediately obtain the information rather than having to look at the information in the back of the monitor.
The front panel
320
includes several buttons to allow the user to select operation modes. The MENU button
350
is used to display and allow the user select the menu items. In particular, if the MENU button is held down for more than 5 seconds, the monitor information will be displayed on the screen.
Thus, the status information is stored in EEPROM prior to shutdown to facilitate the diagnosis and repair when the defective monitor is returned. In addition, the display of the monitor indication information on the screen provides immediate access of information to the user and to repair personnel.
While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications of the illustrative embodiments, as well as other embodiments of the invention, which are apparent to persons skilled in the art to which the invention pertains are deemed to lie within the spirit and scope of the invention.
Claims
- 1. A method for storing status information prior to shutdown of a video monitor due to a failure, the method comprising:obtaining an indication of an operational parameter; determining, based on the indication, if the failure occurs warranting shutdown; and if the failure occurs, storing status information in a non-volatile memory for later retrieval during repair, and generating a shutdown sequence to disable the video monitor.
- 2. The method of claim 1 wherein the operational parameter is one of an automatic beam level (ABL), a high voltage level, a horizontal scan signal, and a vertical scan signal.
- 3. The method of claim 1 wherein determining if the failure occurs includes comparing the indication with a predefined value.
- 4. The method of claim 1 wherein the status information includes a user mode table, a horizontal frequency, a vertical frequency, a polarity information, a monitor state, and a sync information.
- 5. The method of claim 4 wherein the monitor state includes an age mode, a phase-locked mode, and a synchronization mode.
- 6. The method of claim 4 wherein the sync information includes a separate sync, a sync on green, and a composite sync.
- 7. The method of claim 1 further comprises displaying a monitor indication upon receiving a user input.
- 8. The method of claim 7 wherein the user input is a holding of a button for a predetermined period of time.
- 9. A video monitor system comprising:a picture tube; a video control circuit coupled to the picture tube for providing control signals and reading an indication of an operational parameter; a video processing circuit coupled to the video control circuit for generating video signals; and a processor coupled to the video control circuit and the video processing circuit for receiving the indication, the processor determining, based on the indication, if a failure occurs, and if the failure occurs, the processor writing status information to a non-volatile memory for later retrieval during repair before shutting down the video monitor system.
- 10. The system of claim 9 further comprises a shutdown control circuit coupled to the processor for generating a shutdown command to the video processing circuit.
- 11. The system of claim 9 further comprises a test interface to allow a retrieval of stored status information.
- 12. The system of claim 9 wherein the non-volatile memory is an electrically erasable programmable read-only memory (EEPROM).
- 13. The system of claims 9, wherein the processor includes an analog-to-digital converter which converts the indication into digital data.
- 14. The system of claim 9 wherein the status information includes a user mode table, a horizontal frequency, a vertical frequency, a polarity information, a monitor state, and a sync information.
- 15. The system of claim 14 wherein the monitor state includes an age mode, a phase-locked mode, and a synchronization mode.
- 16. The system of claim 14 wherein the sync information includes a separate sync, a sync on green, and a composite sync.
US Referenced Citations (10)