DE10229342A1 - Graphics data-processing device for a screen in a car, e.g. for a tachometer, has an image data memory and a graphics controller - Google Patents

Abstract

A graphics controller (GC) (4) is designed to test data for data errors after being read in from an image data memory (5) before output to a screen (8)/matrix display. The GC uses a buffer memory, a decoding unit (9), a control device or a screen output device for testing. The data to be tested has a preset identification to act as a component of a control word for data control. Independent claims are also included for the following: (a) A system for processing graphics data with a data-decoding unit; (b) and for a method for preparing a graphics element for display on a screen in a car.

Description

State of the art

Graphics processing systems that a graphics computing device and a screen, e.g. include a liquid crystal matrix screen, are in more diverse embodiment also for the use in motor vehicles already become known.

Matrix liquid crystal displays with e.g. TFT control are particularly suitable for displaying complex Information in modern motor vehicles. Currently finds on such Display systems merely represent supplementary, not safety-relevant Information takes place.

Those prescribed by law Displays, e.g. For the ABS whose function is e.g. to monitor through the cockpit computer is realized with separate light sources.

Task and Advantages of the invention

The invention is based on the object, in particular in motor vehicles a screen, which is often present anyway, also use to display security-relevant information to be able to.

This task is characterized by the features of claim 1, 6, 10 and 13 solved.

First, the invention of a graphics computing device for controlling a screen in a vehicle, which is an image data memory and a graphics controller. The core of the invention lies now in that the graphics controller is designed to, from the Image data read in data before output to the screen to check for data errors. This represents a first level of security to ensure that a graphical element to be displayed on the screen is actually error-free is displayed on the screen. This makes the system suitable for safety-relevant Representations.

The graphics controller can use a buffer memory and / or a decoder unit and / or a control unit and / or comprise an image output unit. For checking image data, a or more of these functional units are used. Possibly can also perform a coincidence check with these functional units given data.

In a further embodiment For example, the graphics controller is preferably configured to perform a check of Make data that have a given label or associated with a given label.

This can be a test on only safety-related image data are limited, whereas uncritical Image data without identifier need not be checked.

In a further preferred embodiment the label is part of a control word for data control. For example, over the on-board computer the output of a control word for the insertion of a graphic Object initiated on a screen. Does this control word contain a given Labeling with regard to safety aspects, the associated data checked.

One or more units of the graphics controller take in an exam preferably a data check, e.g. in the form of creating a checksum in front. The result is then compared to additional data, e.g. in a "header" to the data to be checked stand.

Shows the verification that the data is to be displayed graphic object are error-free, this data is transmitted to the screen. Otherwise, e.g. an error output and a debugging sequence be initiated. This task can be done by the graphics controller or a external unit become.

In a graphics data processing system with a graphics data processing device, preferably a graphic data processing device just described and a screen with data decoding unit lies at the heart of the invention in that the decoding unit is adapted to be transmitted by the graphics computing device Data before or when output to the screen for data errors to consider, which is transmitted to the decoding unit by the graphics processing device become.

Through this approach finds a surveillance from transmitted Data in the immediate vicinity of the display instead. If already in the graphics controller a check of Data has taken place this additionally the transmission path from the graphics controller to the immediate display environment. By this measure can already achieve a comparatively high level of security In fact, a graphic element to be displayed on the screen will also be is displayed in the required form.

In a preferred embodiment of the invention, the decoding unit comprises an image interface to the screen, wherein an evaluation of image data not visible on the screen takes place for checking data for data errors. Preferably, a safety-critical graphical object has an image size that is not defined by a graphic element to be displayed, but is extended by an area that is transparent, for example, in the later fade-in. For checking the graphic element, an identifier, for example in the form of a color marking, is provided on one or more edges, wherein this edge region does not fall into the visible region of the screen in the representation of the graphic element. With it influenced the identifier does not display the graphic element on the screen, but can be used to check whether the data of the graphical element to be displayed is faulty.

In this type of test can an evaluation of horizontal and / or vertical control data respectively. If both the horizontal and vertical control data are checked, can with even greater certainty on the correctness or defectiveness of the data of the actually be closed to be displayed graphical element.

The in the not visible edge area ID of image data is preferred for evaluation compared with a given identifier.

Another level of review of graphical Objects in a graphics data processing system, e.g. one Graphic data processing system as just described, which is a graphics data processing device and has a screen is that on the screen Means are provided to the insertion of graphic elements optically and / or electrically tested. By this procedure will be an exam whether to be displayed on the screen graphic element in the actual Representation is faulty. Such a way of monitoring enough highest safety requirements, in particular, the rule prescribed by the legislature that in motor vehicles with safety-critical displays a function monitoring the ads guaranteed have to be. The security of the system is further increased if an electrical and / or optical test with one or more of monitoring options described above combined.

In a preferred embodiment the invention, the means for testing are designed to be an am horizontal and / or vertical edge of a given image area to evaluate the identifier. Such a positioning of a Identifier, e.g. one or more color marks will appear outward little showy in appearance or can be completely covered by appropriate covers so that a viewer barely gets the identifier for examination or not at all. If the identifier is displayed correctly will, lets to conclude with a high degree of certainty that this is to be represented graphic element is displayed correctly in the same way.

Furthermore, it is preferred if the means of testing a light guide, e.g. an optical fiber sheet, comprising one Part of the display area of the screen, preferably a border area of the screen covers, in particular covers. Leave through this procedure themselves from e.g. Test symbols outgoing light signals from the screen for evaluation to an evaluation unit.

Another aspect of the invention refers to the graphic objects for a representation on a To prepare the screen. The core idea of such a treatment is that a graphical element to be displayed in a Image area that is larger than the graphical element and that the image area is provided with an identifier that is outside of the graphic element. Preferably, the image area transparent around the graphic element to be displayed, so that a Viewer perceives only the graphic element to be displayed.

Furthermore, it is preferred if the image area is in the horizontal and / or vertical border area a screen extends.

For the case that a review of the graphic object when writing on the screen by examining the Object data is done, it is preferred if image data for the identifier lie in an area that is not shown on the screen become. By this measure is the identifier for a viewer not visible. A check of the identifier takes place so to speak in a virtual area of the picture instead. Will, however, in particular a visual inspection made, whether a graphical element of a graphic object indeed displayed on the screen, the identifier should be in one Area of the graphic object that is displayed on the screen becomes.

In a preferred embodiment the invention, the identifier in the image area in a horizontal and / or vertical edge area of the screen. On this way, the rest of the screen content by an identifier only insignificantly or with appropriate lamination not disturbed at all.

drawings

Several embodiments of the invention are in the drawings, indicating further details and advantages shown. Show it

1 a highly schematic block diagram of a graphics data processing system,

2 a detailed block diagram of the graphics data processing system according to 1 .

3 a section of the graphics data processing system according to 1 and 2 in a further specified block diagram,

4 a flowchart to illustrate the flow control within the in 3 shown control block,

5 a flowchart for the data decoding in the decoding unit according to 3 .

6 the image structure of a safety-critical graphic object,

7 a schematic representation of a speedometer in a car to illustrate representations in the visible and invisible area of a screen,

8a and b a timetable of signals for a horizontal ( 8a ) and a vertical ( 8b ) Control of a matrix display and

9a - c a schematically illustrated matrix display with imaged thereon tachometer and attached thereto foil light guide in a plan view ( 9a ), a side view ( 9b ) and a partial enlargement of the plan view with side view in the region of the dashed circle ( 9c ).

description the embodiments

In 1 Figure 4 is a schematic block diagram of a graphics data processing system 1 shown. The wide arrow connections between the individual function blocks symbolize connections 2 for data exchange.

The graphics data processing system 1 includes a microprocessor 3 , a graphics controller 4 , a flash memory 5 , a display 6 as well as a RAM memory 7 in the 2 and 3 within the graphics controller 4 is arranged.

The connection 2 between the first four left blocks 3 . 4 . 5 and 7 is for example designed as a data bus.

In 2 is the display unit 6 shown in more detail.

The display unit 6 here includes an example of a matrix display 8th on which a speedometer is shown and a decoding unit 9 for receiving data from the graphics controller 4 and the control of the matrix display 8th ,

A partial representation of the block diagram according to 2 in which the internal structure of the graphics controller 4 can be seen, shows 3 ,

In addition to the already known function block 7 the graphic controller comprises a communication port 10 for communication with the microprocessor 3 , a control unit 11 , a flash interface 12 to flash memory 5 , a decoding unit 13 , a transfer unit 14 , an image output unit 15 and a video block 16 , The data flow in the graphics controller 4 through the individual blocks 12 . 13 . 14 . 7 and 15 is by the arrow 17 symbolizes.

The flow control within the control unit 11 when reading a graphic object is in 4 illustrated by a flowchart with function blocks. The first block 41 symbolizes the beginning of the reading process of a graphic object. From the microprocessor 3 receives the control unit 11 eg a control signal: "display graphical object"; in 4 through the arrow 42 and the function block 43 symbolizes. The control unit then checks the control word (block 44 ). If the data word is valid, then according to arrow 44a continue, otherwise an error message (arrow 44b ). Object attributes are extracted from the control word (function block 45 ) contained in the control word. In the block 46 The object attributes are then checked to see whether the graphical object to be displayed is a safety-critical object. If this is the case, the control word is entered in a list "Objects with monitoring" (arrow 46a as well as function block 46b ). The control words are in the function block 47 checks whether they are already in a display list, ie whether a corresponding graphical object is already displayed on the screen. If this is not the case, the control word with attributes is displayed in a display list (function block 48 ) (arrows 47a . 47b as well as function block 47c ). The function block 47c symbolizes the process "Copy the control word with attributes to the display list".

If the graphical object to be read in by the control word is already displayed, only an "update" of the attributes takes place before the corresponding control word is entered into the display list (function block 48 ) is registered. This is indicated by the arrows 47d . 47e such as 47f symbolizes, with the function block 47g stands for the function "update of the attributes".

With the display list in the function block 48 finds a decode from the flash memory 5 via the flash interface 12 read data in the decoding unit 13 instead of.

This process is performed by the flowchart according to 5 illustrated. The starting point is the display list with attributes (function block 48 ). The next function block 50 symbolizes the process "load graphic object according to list entry".

In the function block 51 It checks if it is a graphical object that needs to be monitored. For this, a comparison with the list takes place in which objects with monitoring are entered (function block 46b in 4 ). In 5 this functional block is provided with the same reference numeral.

The arrows 51a and 51b symbolize the way, if it is a graphic object that does not need to be monitored. Accordingly, decoding of the data associated with the graphic object (function block 52 ) and a registered letter to the transfer unit 14 for the image data instead.

If, on the other hand, it is a graphic object for which monitoring is to be carried out, the associated graphical data are also first decoded (arrow 51c as well as function block 53 ). Subsequently, however, a test for data integrity takes place (function block 54 ).

In the function block 55 the further processing of the data belonging to the graphic object takes place depending on whether the data are error-free or error-prone. If this is not the case, the data is transferred to the transfer unit 14 instead (arrow 55a ). If an error has been registered, he follows an entry in an error register (function block 56 with arrow 55b ) as well as the output of an error message (function block 57 with arrow 56a ).

The checking process of the graphic objects within the decoding unit 13 thus requires the presentation list 48 and the list 46b the objects to be monitored as a reference.

According to the flowchart, the decoding unit is executed 9 the decoding of graphic data from flash memory 5 , The checking of the graphical data at this point only refers to an integrity test of the stored data sets for the graphical objects that are in the list 46b " Objects with monitoring "The reaction and output of error messages in the detection of mutilated data sets can be designed in many ways (example function blocks 56 and 57 ).

A review of safety-critical objects However, this can also be done by making the data critical to safety Objects have an identifier that lies in an image data area, which is displayed on the screen or just not shown becomes. For example, the identifier lies in a "blanking area" of the image. The identifier can be a symbol, include a color marker, but also a data code.

A record for a graphic object to be checked may have a structure according to 6 respectively.

In contrast to usual data for a graphic object, the image size for the graphic object to be checked becomes 60 not by the element to be displayed 61 but through an extended image area 62 Are defined. The extended image area 62 is preferably transparent in the later fade-in. An object identifier 63 is in the edge area of the extended area 62 , here in the form of a color marker 63 arranged.

7 illustrates the case where the extended object area with identifier falls within a range of image data displayed on the visible part of the screen, here the matrix display 8th , not shown. This information is exemplary in "blanked" rows and columns of the image, which are never displayed on the screen. The width and height of the visible area of the matrix display 8th in 7 is through the custom arrows 71 and 72 shown. however, data of an image area larger than the visible image area is processed. The height and width of the visible image area together with the virtual image area not shown is determined by the dimensions 73 and 74 certainly.

The size of a frame buffer is determined by the physical resolution of the screen, ie the visible pixels (in 7 71 × 72 ) and the non-visible pixels (in 7 [ 74 - 72 ] × [ 73 - 71 ]) certainly . D. H. The size of a frame buffer is on actual and virtual pixels in the range 73 × 74 interpreted.

7 shows by way of example an insertion of a single safety-critical graphic object. Depending on the design, the security-critical graphic object has at least one identifier, in this case on all four edges (which are not visible). This increases the "verification reliability". The shape of a respective graphical object and the position of an "object identifier" depends on the planned insertion position, ie the distances to the image borders.

In 7 is the graphic object to be checked 75 so faded in that the object identifier 76 . 77 . 78 . 79 is not displayed on the screen. In this case, monitoring of safety-critical graphical objects is performed at the time of image output.

The data for the identifier 76 . 77 . 78 . 79 are accordingly in a range of image memory for non-visible pixels. A review of the graphic object 78 This is done by checking these data from one identifier part or several identifier parts 76 . 77 . 78 . 79 , If the checked identification parts are error-free, it is concluded that the data for the visible region of the graphic object to be checked is also correct.

In the 8a and 8b FIG. 12 is a timing chart for electrical signals for horizontal and vertical driving in image output on a liquid crystal matrix display as in the prior art.

For the horizontal control are according to 8a The following signals are shown from top to bottom. Horizontal synchronization "H _Sync ", clock "P _Clk " and data signals "Data". In the area "H _{v i s} " are visible pixel data, in the area "H _ges - H _vis " are not shown pixel data.

With regard to the vertical signals are in 8b following presented:

Vertical synchronization "V _Sync ", horizontal synchronization "H _Sync " and data for visible and unillustrated lines "Data". The data for the visible lines are in the range "V _vis ", the data for the lines not shown in the range "V _ges - V _vis "

In the decoding unit 13 the display unit 6 Data in the unillustrated area is checked for an integrity test of the data in the visible area of a safety-critical graphic object to be displayed. For example, data for an identifier in the image area (not shown) must contain all the components of the primary colors red, green and blue and have a specific structure for this purpose. If this is not the case, an incorrect representation of the graphic object in the visible range is concluded.

An error detection can, however, also be extended to the extent that, in addition or in isolation, it is visually checked whether in the picture screen information to be displayed actually in the desired manner.

For this purpose, a security-critical graphic object to be inserted can be inserted in accordance with 6 be modified so that the identifier 63 is located in the visible edge region of a display and this edge region is monitored, for example, with a light guide with regard to the actual graphical representation. Insofar as the correct representation of the identifier is detected via the optical waveguide, there is also a high degree of certainty in the error-free representation of the rest of the graphical object and thus in a faultless representation of the actual information.

In the 9a to 9c is a liquid crystal matrix display 90 with a speedometer shown on it 91 and at the lower left edge of an identifier 92 displayed. The identifier 92 is exemplary here within eg 3 Columns and consists of the representation of the three primary colors red, green and blue, each as a juxtaposed rectangles.

About a part or the full column area 93 the three columns is a light guide foil 94 arranged, with which in particular the identifier 92 decouple to evaluation means (not shown).

If the evaluation means detect a garbled display of the identifier 92 , there is a high degree of certainty in a likewise faulty representation of a remaining graphical object linked to it.

By means of a corresponding structure of a graphic object to be displayed (size, position, orientation), it is simultaneously possible by an associated object identifier to check the functionality of a corresponding row and / or column driver. The condition for this is that the size of the object to be displayed is typically less than 200 × 200 pixels, optical and / or electrical feedback is provided about the representation of the "object identifier" in both the horizontal and vertical directions, and the position is within a driver tile of the drive frame for the display 90 located.

Claims (16)

Graphic data processing device for a screen ( 8th . 90 ) in a vehicle, in particular a car, with an image data memory ( 5 ) and a graphics controller ( 4 ), characterized in that the graphics controller ( 4 ) is adapted from the image data memory ( 5 ) read data before output to the screen ( 8th . 90 ) to check for data errors. Device according to Claim 1, characterized in that the graphics controller ( 4 ) a buffer memory ( 7 ) and / or a decoding unit ( 9 ) and / or a control unit ( 11 ) and / or an image output unit ( 15 ) and that at least one of these functional units ( 7 . 9 . 11 . 15 ) is involved. Device according to claim 1 or 2, characterized in that the graphic controller ( 4 ) is adapted to perform a test of data having a predetermined label or are associated with a given label. Device according to one of the preceding claims, characterized in that the marking is part of a control word for the Data control is. Device according to one of the preceding claims, characterized in that the graphics controller ( 4 ) is designed to perform a data check on data to be checked and to compare the result with additional data of the checked data. Graphic data processing system with a graphics data processing device, in particular according to one of the preceding claims and a screen ( 8th . 90 ) with data decoding unit ( 9 ), characterized in that the decoding unit ( 9 ) is adapted by the graphics computing device ( 4 . 5 ) before or during the output to the screen to check for data errors. System according to claim 6, characterized in that the decoding unit ( 9 ) an image interface to the screen ( 8th . 90 ), where for the examination of data for data errors an evaluation of not on the screen ( 8th . 90 ) visible image data takes place. System according to claim 7, characterized in that in the exam an evaluation of the horizontal and / or vertical control data for the Screen takes place. System according to one of claims 6 to 8, characterized in that for checking in on the screen ( 8th . 90 ) data elements which are not visible image data, eg symbols ( 63 . 76 . 77 . 78 . 79 ) are compared with predetermined data elements. Graphic data processing system with a graphic data processing device and a screen ( 8th . 90 ), in particular according to one of claims 6 to 9, characterized in that on the screen ( 8th . 90 ) Medium ( 94 ) are provided to the display of a graphical identifier ( 92 ) visually and / or electrically. System according to claim 10, characterized gekenn records that the funds ( 94 ) are designed for testing, an identifier located at the horizontal and / or vertical edge of a given image area ( 92 ). System according to claim 10 or 11, characterized in that the means for testing a light guide ( 94 ) that covers part of the display area of the screen ( 8th . 90 ) detected. Process for the preparation of a graphic element ( 61 ) for display on a screen ( 8th . 90 ) in a vehicle, characterized in that the graphical element ( 61 ) in an image area ( 62 ) that is larger than the graphical element and that the image area ( 62 ) with an identifier ( 63 ) outside the graphical element ( 61 ) lies. Method according to claim 13, characterized in that the image area ( 62 ) into the horizontal and / or vertical border area of a screen ( 8th . 90 ) on which the graphic element is displayed. Method according to claim 13 or 14, characterized in that image data for the identifier ( 63 ) are in an image data area that is displayed on the screen ( 8th . 90 ) is not shown. Method according to one of claims 13 to 15, characterized in that image data for the identifier ( 63 ) are within an image data area that is displayed on the screen ( 8th . 80 ) is shown.