Abstract:
A device and a method for reproducing information in a motor vehicle include, as part of a keyless access system and/or drive authorization system, a portable transponder for sending a code via a transceiver to a control device arranged in the motor vehicle. Access authorization and/or drive authorization are granted if the control device receives a valid code. A display is arranged in the vehicle. The display displays specific data based on an output signal from the control device.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a device and a method for reproducing information in a motor vehicle. 
     BACKGROUND INFORMATION 
     In German Published Patent Application No. 196 480 42 is discussed a motor vehicle having a key for to identifying an authorized user. Data such as the customer&#39;s address, the vehicle ID number, or the odometer reading are stored in the key. At a workshop the key is placed in a read device, which is connected to a computer and on whose screen a dialog is carried out in order to read out the key data. However, the data can only be displayed if a password is entered manually. 
     This device may only be suitable for reading out pertinent data if it is used in conjunction with an external device. 
     SUMMARY OF THE INVENTION 
     An object of an exemplary embodiment and/or exemplary method of the present invention is to provide a display device having additional functions, for normal use of the vehicle. 
     An exemplary device according to the present invention for reproducing information in a motor vehicle includes one (or a plurality) of portable transponders as part of a keyless access system and/or drive authorization system, which sends a code to a control device inside the vehicle. Access authorization and/or drive authorization is granted if the control device receives a valid code. It includes a display, which is arranged inside the vehicle. The display displays specific data based on an output signal from the control device. 
     The display can only be activated if a valid code transmitted by the transponder is received. The pertinent data are only made available to a user who has thus demonstrated that he is authorized. Other persons who are not in possession of a valid transponder cannot gain access to these data. Based on the code received, the display can be updated automatically, further operating signals from the user not being necessary to accomplish this. Therefore, the code signal from a transponder is suitable for this initiation procedure for the display, as the code signal transmission procedure is already carried out before initiation of the start procedure for the vehicle. Thus, the user can be supplied with pertinent information about the vehicle&#39;s operating condition in advance before he operates the ignition. The code signal of a transponder is triggered automatically upon operation of the outside door handle, the ignition/start switch, and the remote control button of the transponder (if present). 
     According to another exemplary embodiment, the data is also displayed if a further operating element, a door contact, has been operated. The combination of the transponder query and an output signal from an operating element provides security against unauthorized access to the data, and the display is not activated until the instant when operation of an operating element indicates that the user is inside the vehicle. 
     According to another exemplary embodiment, data which depend directly on the code received by the control device is transmitted to the display. To accomplish this, the control device sends out a search signal which addresses all transponders assigned to the vehicle. The transponders that are located within the control device&#39;s transmission range send back a corresponding answer signal. Based on the incoming signals, the control device can determine which transponders are present. This information is forwarded to the display. Thus, the user is informed of which transponders are located inside the vehicle. In particular, this information reminds the driver before he leaves the vehicle that he should take the transponders that are in the vehicle with him so as to reduce the risk of unauthorized starting of the vehicle. 
     The display duration may be limited to a predefined time. This should at least better ensure that no operation intervention to support the functionality of the exemplary method should be necessary. According to another exemplary embodiment, the current display duration is extended by a further full basic duration if a further trigger event occurs before the predefined display time has elapsed. In addition to straightforward timer control, the display duration can also be coupled to the occurrence of a further event. This event may be the starting and/or stopping of the engine or the locking of the vehicle. 
     The exemplary method according to the present invention for reproducing information in a motor vehicle may use a portable transponder as part of a keyless access system and/or drive authorization system which transmits a code via a transceiver to a control device arranged inside the vehicle, access authorization and/or drive authorization being granted if the control device receives a valid code. A display is arranged inside the vehicle, the display displaying specific data based on an output signal from the control device. The exemplary method involves the following steps: 
     Transceiver sends out a search signal which causes the transponder to send back a code; 
     The control device evaluates the code received via the transceiver; and 
     The display is activated. 
     The data exchange carried out in connection with the authorization query provides information as to which transponders are located within the transceiver&#39;s coverage range. This information is forwarded to the display in the next step, and is available to the user immediately. According to another exemplary embodiment, the display is also triggered even if no code or an unauthorized code is received during a time period that begins with the sending out of the search signal. The user can be made aware of this critical situation immediately, as the corresponding query procedure for transponder recognition has already been carried out. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a block diagram. 
     FIG. 2 shows a further display. 
     FIG. 3 shows a flow chart relating to the exemplary embodiment and/or exemplary method. 
    
    
     DETAILED DESCRIPTION 
     Memory  12  and transceiver  14  are arranged in control device  10 . Transceiver  14  exchanges data with first transponder T 1  and if necessary with second transponder T 2  and nth transponder Tn. For each of these transponders T 1 , T 2 , Tn, an accompanying name N 1 , N 2 , Nn of a transponder user, settings E 1 , E 2 , En, and confidential data V 1 , V 2 , Vn are stored in memory  12 . In each of transponders T 1 , T 2 , Tn, special data S 1 , S 2 , Sn are stored in a memory. Control device  10  communicates via bus system  18  with display unit  24 , which includes display  26 . A signal from door switch  20  and a signal from operating element  22  are conveyed to bus system  18 . Diagnosis interface  28  via which, in conjunction with input/output unit  30 , data can be read in or out, is provided on bus system  18 . In normal operating mode, names N 1 , N 2 , Nn, binary information (x, 0) and settings E 1 , E 2 , En that are assigned to transponders T 1 , T 2 , Tn are displayed to the user via a display. 
     In a special operating mode, name N 1 , N 2 , Nn, the binary information, settings E 1 , E 2 , En, confidential data V 1 , V 2 , Vn and special data S 1 , S 2 , Sn that are assigned to the transponders T 1 , T 2 , Tn in question appear on the display; as an alternative, just parts of this information are displayed. 
     The flow chart shown in FIG. 3 is now used for describing the exemplary method and/or how the exemplary device according to the present invention functions. A user who is in possession of first transponder T 1  approaches the vehicle. In order to achieve access authorization, he operates the door handle (Step  101 ). The corresponding signal exchange is evaluated by control device  10 . Transceiver  14  of control device  10  thereupon sends out a search signal. First transponder T 1 , which is within the range of transceiver  14 , sends back an answer signal/code to control device  10 . Based on the answer signal sent back, control device  10  determines which transponders T 1 , T 2 , Tn are located within the range of transceiver  14 . 
     The evaluation as to which transponder T 1 , T 2 , Tn is present may be performed using, for example, a characteristic transmission time delay for the answer signal which distinguishes transponders T 1 , T 2 , Tn from each other. Each transponder T 1 , T 2 , Tn is assigned a corresponding time slot. If an answer signal is received within this characteristic time slot, control device  10  determines that transponder T 1 , T 2 , Tn that answers within this time slot is within range. Based on this evaluation procedure, the binary information is generated as to whether the transponder in question T 1 , T 2 , Tn is present (x) or not (0). 
     Triggering of the authorization query in Step  103  can also be carried out or performed in conjunction with opening or closing of the doors, or upon operation of an operating element in conjunction with a start or stop procedure of the vehicle. In this context, these transceivers  14  which cover the vehicle interior are triggered with a view to sending out a search signal. The incoming signals from transponders T 1 , T 2 , Tn may be used to determine which transponders T 1 , T 2 , Tn are located inside the vehicle. In Step  111 , this information is made available to the display. 
     Provided a valid answer signal is received at transceiver  14 , authorization query  103  is carried out next. To accomplish this, a signal is sent to first transponder T 1 , which has been recognized as being present, and is processed by first transponder T 1 . First transponder T 1  sends the processed signal back as a code. At the same time, the identical procedure for determining the expected code is carried out in control device  10 . 
     If the incoming code from first transponder T 1  matches the expected code, the authorization procedure is deemed to have been carried out successfully (Step  105 ). If they do not match, the authorization procedure is terminated so that there is no result (Step  107 ). Based on the authorization query (Step  103 ), either authorization for access to the vehicle, or a drive authorization, which enables the control devices required for operation and thus allows the driver to start the engine, is granted. If the authorization query has been carried out successfully, control device  10  transmits a command signal and the data to be displayed, such as transponder T 1 , T 2 , Tn, name N 1 , N 2 , Nn, transponder-dependent binary information, and settings E 1 , E 2 , En, to display unit  24  via bus system  18 . 
     This data is merely an example. Any desired information may be displayed. Thus for each transponder T 1 , T 2 , Tn the name N 1 , N 2 , Nn of the transponder user in question is stored in memory  12  of control device  10 . This is shown on the screen of display  26  in alphanumeric form. Settings E 1 , E 2 , En may constitute information as to whether the transponder T 1 , T 2 , Tn is blocked for an authorization query. Similarly, transponder-dependent user settings E 1 , E 2 , En could constitute a seat adjustment setting, a mirror adjustment setting or the like. Display unit  24  prepares the data made available by control device  10  and triggers display  26 . This data is visible on display  26  for a predefined length of time. 
     According to another exemplary embodiment, the data is only displayed if the authorization query per Step  103  has successfully been carried out and also an additional event occurs. This additional event could be, for example, the closing of the doors, this being signaled via the signal status of door switch  20 . Control device  10  then forwards a corresponding display command to display unit  24 . Operation of operating element  22  may also constitute an event that triggers display  26 . For example, the user would have to operate the ignition switch or the ignition lock in order for display  26  to be triggered. However, first an authorization query (Step  103 ) would have to have been successfully carried out. The data stored in memory  12  may also be read in and out via diagnosis interface  28  and the accompanying input/output unit  30 . This may also be used, for example, when the device is started up for the first time. 
     In addition to the use of the display in normal mode as described above, in special mode protected data can be queried and overwritten. This protected data may be located in control device  10 , in transponder T 1 , T 2 , Tn, or in both components. As this data is access-protected, the special-mode operation of display  26  has to be initiated via a suitable operating sequence. To accomplish this, one option is for the ignition to be switched on and off a plurality of times. This special operating sequence causes control device  10  to carry out a first authorization query with a first transponder T 1 , as described above in connection with Step  103 . 
     According to the exemplary embodiment and/or exemplary method of the present invention, at least one further authorization query with a further transponder T 2 , Tn must be successfully carried out in order for the special mode data to be displayed. Provided the authorization query has been carried out successfully with a further transponder T 2 , Tn, control device  10  prepares the special mode data to be displayed. The queries described above may be carried out or performed in a single step. For read mode, two transponders T 1 , T 2  may be enough; for write mode, e.g., entering a new owner, all valid transponders T 1 , T 2 , Tn must be available for querying. The number of valid transponders T 1 , T 2 , Tn can be determined from the contents of the memory, and allows the write mode to be enabled once the number of transponders T 1 , T 2 , Tn has been determined and the subsequent comparison has been carried out. 
     In addition to, or also independently of, the data already displayed in normal mode, in special mode confidential data V 1 , V 2 , Vn and/or special data S 1 , S 2 , Sn stored in transponders T 1 , T 2 , Tn may also be displayed (see FIG.  2 ). Control device  10  transmits a suitable command via transceiver  14  to the transponders T 1 , T 2 , Tn that are in range, so as to cause them to send back the special data S 1 , S 2 , Sn in question. Special data S 1 , S 2 , Sn and the data stored in memory  12  are forwarded to display unit  24  via bus system  18  with the help of an appropriate special display command. 
     Display  26  is now structured as shown in FIG.  2 . Confidential data V 1 , V 2 , Vn and special data S 1 , S 2 , Sn may constitute information regarding the transponder owner, the address, service information regarding the vehicle, the vehicle&#39;s official ID, the vehicle registration certificate, the motor vehicle certificate, the chassis number, the engine number, or the insurance number. Thus, there is no need for an external read-out device. As described herein, it is easy for the workshop staff to access the data provided they are in possession of the necessary number of valid transponders T 1 , T 2 , Tn. If the vehicle&#39;s owner changes, data can be changed and the changes verified with the help of display  26  and input/output unit  30 , provided all authorized transponders T 1 , T 2 , Tn are presented. 
     According to another exemplary embodiment, display  26  is also triggered if the authorization query carried out in Step  103  does not indicate a valid code or no code is received by transceiver  14  within a time period that begins when the search signal is sent out. Instead of immediate termination, Step  107  could also be used to trigger display unit  24  with a view to issuing a warning indicating “unauthorized transponder” or “no transponder.” However, security-relevant information would not be displayed. In conjunction with a warning signal, display  26  may also be supported by visual or acoustic means (radio, or, for example, a piezoelectric signal generator). 
     Memory  12  may also be arranged in any other control device. In normal mode, data stored in transponders T 1 , T 2 , Tn may also be sent to display  26 , the necessary transfer being carried out. Furthermore, transceiver  14  and control device  10  do not have to be structurally integrated. Instead, a plurality of transceivers  14  may be arranged at different points in the vehicle so as to ensure reliable detection of transponders T 1 , T 2 , Tn that are present. According to other exemplary embodiments, the signals from door switch  20  and/or operating element  22  are transmitted directly to control device  10 . In addition to a visual display  26 , the display unit  24  may be a display that merely indicates the transponders that are present via a back-lit display, or it may be an acoustic display. The door switches and tailgate switches may be connected directly to control device  10  to trigger the authorization query and/or display activation. The operating element  22  may be integrated into display unit  24 . Furthermore, the authorization query described in connection with Steps  101  and  103  may be carried out in a single step and with one-time sending back of a transponder signal that is evaluated for authorization purposes.