# US 8,543,349 B2 · Test device, display device, and method for checking a validity of display signals > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,543,349 B2 - Document ID: US8543349B2 - Status: Granted - Kind: B2 - Application number: 12/734,051 - Filed: 2008-10-09 - Published: 2010-11-11 - Granted: 2013-09-24 - Earliest claimed: 2007-10-10 - Assignees: Robert Bosch GmbH - Applicants: Igor Katchan; Markus Lindner - Inventors: Igor Katchan; Markus Lindner - Web page: https://patentgrep.com/patent/US8543349B2 ## CPC - G01D 3/00: Indicating or recording apparatus with provision for the special purposes referred to in the subgroups - G06F 11/2221: {to test input/output devices or peripheral units} - 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)} - G06F 3/14: Digital output to display device {; Cooperation and interconnection of the display device with other functional units} - G09G 3/006: {Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays (testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309)} - G09G 5/003: {Details of a display terminal, the details relating to the control arrangement of the display terminal and to the interfaces thereto (specific for a CRT G09G1/165; for a flat panel G09G3/2092)} - G09G 2320/08: Arrangements within a display terminal for setting, manually or automatically, display parameters of the display terminal - G09G 2330/12: Test circuits or failure detection circuits included in a display system, as permanent part thereof - G09G 2370/045: using multiple communication channels, e.g. parallel and serial - H04N 17/00: Diagnosis, testing or measuring for television systems or their details - G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A test device for checking the validity of display signals pertaining to a predefined image includes a device for ascertaining image data from the display signals, device for determining a test value of the image data, and a comparator unit for comparing the ascertained test value with a stored test value pertaining to the image, a validity of the display signals being established in the case where the two test values coincide. ## Claims ### Claim 1 A test device for checking the validity of display signals corresponding to a predefined image, comprising: at least one device configured to: evaluate a status of an enable signal; ascertain image data from the display signals based on the evaluated status of the enable signal; determine a test value from the ascertained image data; compare the determined test value with a stored test value corresponding to the image data; and determine that the display signals are valid conditional upon that the determined test value is determined by the comparison to match the stored test value. ### Claim 2 (depends on 1) The test device as recited in claim 1, further comprising: an interface configured to transmit at least one further test value pertaining to at least one additional image. ### Claim 3 (depends on 1) The test device as recited in claim 1, wherein the test device is a component of a display device that includes: a display for displaying images; and a graphic controller for generating display signals used for generating an image on the display, the display signals from which the image data is ascertained being generated by the graphics controller. ### Claim 4 (depends on 3) The test device as recited in claim 3, wherein the display device further comprises an interface configured to transmit to the test device the test value. ### Claim 5 (depends on 4) The test device as recited in claim 4, wherein: the display device further comprises a data link between the graphic controller and the display; and the test device accesses the display signals between the data link and the display. ### Claim 6 (depends on 4) The test device as recited in claim 4, wherein: the display device further comprises a memory storing image data of at least one test image and at least one test value corresponding to the at least one test image. ### Claim 7 (depends on 4) The test device as recited in claim 4, wherein the display device is located in a motor vehicle. ### Claim 8 (depends on 3) The test device as recited in claim 3, wherein the determination of the test value includes selecting bit values from display signals in accordance with a predefined clock cycle. ### Claim 9 (depends on 3) The test device as recited in claim 3, wherein the determination of the test value includes a polynomial division. ### Claim 10 (depends on 3) The test device as recited in claim 3, wherein the stored test value is determined from ascertained image data of the predefined image. ### Claim 11 (depends on 1) The test device as recited in claim 1, wherein the determination of the test value includes selecting bit values from display signals in accordance with a predefined clock cycle. ### Claim 12 (depends on 1) The test device as recited in claim 1, wherein the determination of the test value includes a polynomial division. ### Claim 13 (depends on 1) The test device as recited in claim 1, wherein the stored test value is determined from ascertained image data of the predefined image. ### Claim 14 A method for checking a validity of display signals generated from image data of a predefined image, comprising: evaluating, by a processing circuit, a status of an enable signal; ascertaining, by the processing circuit, image data from the display signals based on the evaluated status of the enable signal; determining, by the processing circuit, a test value from the ascertained image data; comparing, by the processing circuit, the determined test value with a stored test value corresponding to the image data; and determining, by the processing circuit, that the display signals are valid conditional upon that the determined test value is determined by the comparison to match the stored test value. ### Claim 15 A method for checking a validity of display signals generated from image data of a predefined image, comprising: ascertaining, by the processing circuit, image data from the display signals; generating, by the processing circuit, a test value corresponding to the ascertained image data, wherein the generating includes at least one of: selecting bit values from display signals in accordance with a predefined clock cycle; and a polynomial division; comparing, by the processing circuit, the determined test value with a stored test value corresponding to the image data; and determining, by the processing circuit, that the display signals are valid conditional upon that the determined test value is determined by the comparison to match the stored test value. ### Claim 16 (depends on 15) The method as recited in claim 15, wherein the generating includes the selecting of the bit values in accordance with the predefined clock cycle. ### Claim 17 (depends on 15) The method as recited in claim 15, wherein the generating includes the polynomial division. ### Claim 18 A method for checking a validity of display signals generated from image data of a predefined image, comprising: ascertaining, by the processing circuit, image data from the display signals; determining, by the processing circuit, a test value from the ascertained image data; comparing, by the processing circuit, the determined test value with a stored test value that is determined from ascertained image data of the predefined image; and determining, by the processing circuit, that the display signals are valid conditional upon that the determined test value is determined by the comparison to match the stored test value.