JP5781897B2 - Vehicle instrument - Google Patents

Description

  The present invention relates to a vehicular instrument that displays information representing at least one measurement value.

  Generally, an instrument panel unit mounted on an automobile is provided with various instruments such as a speedometer, a tachometer, a hydraulic gauge, a water temperature gauge, and a fuel fuel gauge. Usually, each of these instruments acquires a measured value by reading an electrical signal output from a sensor mounted on the corresponding vehicle, and displays the measured value.

  In recent years, various types of electronic control units (ECUs) are mounted on vehicles, and these are often connected to each other via a communication network on the vehicle. Therefore, the instrument panel unit can also acquire necessary measurement value information from other electronic control units.

  However, the type and number of electronic control units mounted on an actual vehicle vary depending on the vehicle type, grade, destination, etc. of the vehicle. Therefore, various variations of the configuration of the instrument panel unit must be prepared in accordance with the difference in the type, grade, destination, etc. of the vehicle on which the instrument panel unit is mounted.

  Thus, for example, in the prior art disclosed in Patent Document 1, the correspondence between the variation of the instrument panel unit and the information supply means of each instrument is registered in advance in a table as shown in FIG. doing. By referring to the information in this table, variations of the vehicle can be associated with variations of the instrument panel unit, and one type of instrument panel unit can be mounted on various types of vehicles.

  Specifically, when the vehicle meter can acquire target information from at least one of the sensor connected to the vehicle instrument and the electronic control unit connected via the CAN communication network, the output of the sensor and communication are obtained. Which information is to be selected is determined by a signal obtained by CAN communication. That is, the vehicle meter switches the information acquisition source to sensor output or CAN communication according to the control signal output by the vehicle-side electronic control unit.

JP 2010-195216 A

  However, as in the technique of Patent Document 1, when the selection of the acquisition source of information required by the vehicle instrument is switched by an instruction from another electronic control unit, the vehicle instrument cannot operate alone. . That is, in one state where a system is configured by combining one or a plurality of electronic control units actually mounted on a vehicle and a vehicle instrument, a vehicle instrument is connected to one electronic control unit so as to perform a predetermined operation. The function to control must be incorporated. For this reason, there are restrictions on variations of electronic control units mounted on the vehicle.

  Of course, the vehicle instrument can be configured to operate independently. In that case, monitoring and determining whether or not appropriate information can be acquired for each candidate so that any of a plurality of candidates (for example, sensor output and CAN communication) assigned in advance can be selected as an information acquisition source. It is envisaged to go and select automatically.

  However, when the vehicular instrument determines the information acquisition source by itself as described above, it takes time-consuming processing to determine the selection state of the information acquisition source from among a plurality of candidates. There is a need. In particular, in the case of instrument panel units mounted on vehicles, it is necessary to decide where to obtain information for each of the various instruments such as speedometers, tachometers, hydraulic gauges, water temperature gauges, fuel gauges, etc. It takes time.

  Also, in the case of an instrument panel unit mounted on a vehicle, every time the ignition switch is turned on (every time the power is turned on), the above processing is performed and then the normal display state is entered. , The time required to start the display becomes longer.

  In reality, there is almost no opportunity for a vehicle instrument to switch the source of information. In other words, after the variation of the vehicle on which the corresponding vehicle instrument is actually mounted is determined, if the vehicle instrument determines the information source once according to this variation, it is not necessary to switch the selection state thereafter. . It is important to provide a function of switching information acquisition destinations despite the low frequency of use. However, this function is a heavy processing burden.

  Furthermore, in an environment where each of a plurality of candidates from which the same information is obtained is actually outputting information, there is a possibility that the information source of the vehicle may be switched without permission while the vehicle instrument is displaying. In such a case, the display content changes rapidly, which may give the user a sense of incongruity that a problem has occurred.

  The present invention has been made in view of the above-described circumstances, and the purpose thereof is to automatically select an appropriate candidate when there are a plurality of candidates as sources of necessary information, An object of the present invention is to provide a vehicular instrument capable of preventing an increase in the burden of control processing.

In order to achieve the above-described object, a vehicle instrument according to the present invention is characterized by the following (1) to (5).
(1) A vehicle instrument that displays information representing at least one measurement value,
For a specific measurement target, a display unit that displays the measurement value;
A first signal input unit for inputting first information corresponding to a measurement value of the measurement object;
A second signal input unit for inputting second information corresponding to the measurement value of the measurement object;
A measurement value selection control unit that selects one of the first information and the second information and displays a measurement value of the selected information on the display unit;
Non-volatile information for holding selection information indicating the selection state of the first information or second information in the measurement value selection control unit and unprocessed information indicating whether or not a predetermined selection switching process is in an unprocessed state A storage unit;
Only when the unprocessed information is in an unprocessed state, a selection information determination unit that executes the selection switching process, reflects the result in the selection information, and updates the unprocessed information to processed,
Comprising
about.
(2) The vehicle instrument according to (1) above,
When at least one of the first information and the second information is input as a pulse signal, the selection information determination unit recognizes it as an effective pulse signal only when a plurality of pulses are detected within a predetermined time. Select the information you want to
about.
(3) The vehicle instrument according to (1) above,
The selection information determination unit is a pulse signal that is effective only when a period of a detected pulse satisfies a predetermined condition when at least one of the first information and the second information is input as a pulse signal. Recognize and select relevant information,
about.
(4) The vehicle instrument according to (1) above,
The selection information determination unit selects corresponding information only when the measurement value of the first information or the second information is equal to or less than a predetermined value, and ends the selection switching process.
about.
(5) The vehicle instrument according to (1) above,
The selection information determining unit controls the display unit to a non-display state when executing the selection switching process.
about.

According to the vehicle instrument configured as described in (1) above, the selection switching process is executed only in the predetermined initial state because the unprocessed information is in an unprocessed state, and the first information or the second information The information selection state can be switched. Further, since the unprocessed information is processed after the selection switching process is executed once, the selection switching process is not executed thereafter, and the processing load does not increase.
According to the vehicle meter having the configuration of (2) above, the selection information determination unit can prevent erroneous recognition of pulse-like single noise as an effective pulse signal, and it can be appropriately selected from a plurality of candidates. Can be selected automatically.
According to the vehicle meter having the configuration of (3) above, the selection state of the first information or the second information can be switched only when the period of the actually input pulse is within a predetermined range. . Therefore, an appropriate candidate can be automatically selected from a plurality of candidates.
According to the vehicle meter having the configuration (4), it is possible to prevent the tip state from being switched when the input measurement value is large. As a result, the display value does not change abruptly when switching, and the user does not feel uncomfortable.
According to the vehicle instrument having the configuration (5), it is possible to prevent an invalid value from being erroneously displayed as a measurement value before the switching of the selection state is completed.

  According to the vehicle instrument of the present invention, when there are a plurality of candidates as sources of necessary information, it is possible to automatically select an appropriate candidate and prevent an increase in the burden of control processing. Will also be possible.

  The present invention has been briefly described above. Further, details of the present invention will be further clarified by reading through the modes for carrying out the invention described below with reference to the accompanying drawings.

FIG. 1 is a block diagram illustrating a hardware configuration example of a vehicle instrument according to the embodiment. FIG. 2 is a flowchart showing the main processing of the apparatus shown in FIG. FIG. 3 is a flowchart showing details of the input setting process shown in FIG.

  Specific embodiments of the vehicle instrument according to the present invention will be described below with reference to the drawings.

<Device configuration>
An example of a hardware configuration of a vehicle instrument in the present embodiment is shown in FIG. The vehicular instrument 100 shown in FIG. 1 is configured on the assumption that it is used as an instrument panel unit arranged on an instrument panel of a vehicle such as an automobile.

  As shown in FIG. 1, the vehicle instrument 100 includes a microcomputer 10, a speedometer display unit 11, a tachometer display unit 12, a fuel remaining amount display unit 13, a water temperature meter display unit 14, motor drivers 15 and 16, A distance meter display unit 17, an illumination light source 18, a warning display unit 19, a nonvolatile storage unit 21, a power supply circuit 22, interfaces 23 to 26, an operation switch 27, a FUEL sender 28, and a signal input circuit 29 are provided.

  As shown in FIG. 1, the microcomputer 10 has a read-only memory 10a, a random access memory 10b, a CAN communication circuit 10c, and an A / D conversion circuit 10d, and has various controllable input / output boats. ing. The microcomputer 10 executes a program stored in advance on the read-only memory 10 a and performs various processes for realizing functions required for the vehicle instrument 100.

  The speedometer display unit 11, the tachometer display unit 12, the fuel remaining amount display unit 13, and the water temperature meter display unit 14 are respectively a vehicle traveling speed (SPEED), an engine rotational speed (REV), and a fuel remaining amount (FUEL). It is provided for displaying the measured value of the coolant temperature (TEMP).

  In the present embodiment, a speedometer display unit 11, a tachometer display unit 12, a fuel remaining amount display unit 13 and a water temperature meter display unit 14 are not shown, but an electric motor for driving a scale plate, a pointer, and a pointer, respectively. It has a sensor for detecting the position of the pointer.

  The speedometer display unit 11 and the tachometer display unit 12 are connected to the microcomputer 10 through a motor driver 15, and the fuel remaining amount display unit 13 and the water temperature display unit 14 are connected to the microcomputer 10 through a motor driver 16. Connected with.

  The distance meter display unit 17 is provided for displaying numerical values of an odometer that displays an accumulated travel distance of a vehicle and a trip meter that displays a travel distance of a specific section. The distance meter display unit 17 is configured by a liquid crystal display (LCD) capable of displaying numerical values, and is connected to an output port of the microcomputer 10.

  The illumination light source 18 illuminates the display contents of the speedometer display unit 11, the tachometer display unit 12, the fuel remaining amount display unit 13, the water temperature meter display unit 14, and the distance meter display unit 17 so that it can be easily seen by the driver. Light source. The illumination light source 18 includes a plurality of light emitting diodes (LEDs) connected to the output port of the microcomputer 10.

  The warning display unit 19 is a display unit that is used to warn the driver of failure of each part of the vehicle or occurrence of an abnormal state. The warning display unit 19 is composed of a plurality of light emitting diodes. Each of these light emitting diodes is connected to an independent output port of the microcomputer 10 so that lighting / extinguishing can be individually controlled.

  The nonvolatile storage unit 21 is a memory in which data can be written and read by accessing the microcomputer 10, and can store stored data even when the power supply from the power supply is stopped. In the present embodiment, an EEPROM is used as the nonvolatile storage unit 21, but a flash memory may be used, for example.

  The power supply circuit 22 is based on a DC voltage (+ B) supplied from a vehicle-side power supply (battery or the like), and is stabilized DC voltage (Vcc) required by a circuit such as the microcomputer 10 inside the vehicle meter 100. And generate a reset signal.

  The ignition signal (IGN +) supplied from the vehicle side is input to the input port P1 of the microcomputer 10 via the interface 23. The interface 23 converts the input ignition signal into a signal suitable for the processing of the microcomputer 10.

  The interface 24 connects the microcomputer 10 of the vehicle instrument 100 to a vehicle-side communication network (CAN: Controller Area Network). Generally, various control devices such as an engine electronic control unit (ECU) are connected to the CAN communication network on the vehicle side. Therefore, by connecting the vehicle meter 100 to the CAN communication network, the microcomputer 10 can obtain various information such as the vehicle speed and the engine rotation speed from various electronic control devices on the vehicle side.

  The interface 25 inputs an electric signal of a speed pulse (vehicle speed pulse) directly output from a sensor mounted on the vehicle, performs processing such as noise removal and waveform shaping, and then outputs the processed signal to the input port P3 of the microcomputer 10. .

  A general vehicle is equipped with a vehicle speed sensor that detects rotation of the output shaft of the transmission, and the vehicle speed sensor outputs an electric signal of a speed pulse. Since a pulse appears each time the output shaft of the transmission rotates by a predetermined amount, the vehicle speed (km / h) can be grasped based on the number of pulses within a certain time and the pulse generation cycle.

  This speed pulse is input to various electronic control units mounted on the vehicle as needed, in addition to the vehicle instrument 100. Further, depending on the variation of the vehicle, the speed pulse may be input only to a specific electronic control unit, and the interface 25 of the vehicle instrument 100 may not be connected to the vehicle speed sensor. In that case, it is necessary to obtain information on the required vehicle speed from the other electronic control unit via a network such as CAN communication.

  The interface 26 inputs an electrical signal of an engine speed pulse directly output from a sensor mounted on the vehicle, performs processing such as noise removal and waveform shaping, and then outputs the processed signal to an input port P4 of the microcomputer 10.

  A general vehicle is equipped with a rotation sensor that detects the rotation of the drive shaft of the engine, and this rotation sensor outputs an electric signal of an engine speed pulse. Since a pulse appears every time the drive shaft of the engine rotates by a predetermined amount, the actual engine speed (rpm) can be grasped based on the number of pulses within a predetermined time.

  The engine speed pulse is input to various electronic control units mounted on the vehicle as needed, in addition to the vehicle instrument 100. Further, depending on the variation of the vehicle, the engine speed pulse may be input only to a specific electronic control unit, and the interface 25 of the vehicle instrument 100 may not be connected to the engine rotation sensor. In that case, it is necessary for the vehicle instrument 100 to obtain information on the required engine speed from another electronic control unit via a network such as CAN communication.

  The operation switch 27 is a switch that can be operated by the driver, and is used for switching the display of the odometer / trip meter and resetting the display value of the trip meter. The operation switch 27 is connected to the input port P5 of the microcomputer 10.

The signal input circuit 29 is provided for inputting an electric signal representing the remaining amount of fuel to the microcomputer 10.
In a general vehicle, a float that moves up and down in accordance with the liquid level in a fuel tank and a FUEL sender 28 that detects the position of the float are provided. In the example shown in FIG. 1, since it is assumed that the FUEL sender 28 is composed of a potentiometer (variable resistor), the signal input circuit 29 converts the resistance value of the FUEL sender 28 corresponding to the remaining fuel amount into an analog voltage. The data is converted and output to the analog input port P6 of the microcomputer 10.

  In addition, depending on the variation of the vehicle, there is a possibility that the FUEL sender 28 is not connected to the vehicle meter 100 but is connected to another electronic control unit. In that case, the vehicle meter 100 needs to acquire information on the remaining fuel amount from another electronic control unit via a network such as CAN communication.

<Operation of the device>
The main processing contents of the vehicle instrument 100 shown in FIG. 1 are shown in FIG. This process is realized by the operation of the microcomputer 10. The process shown in FIG. 2 will be described below.

  When power is supplied to the vehicle instrument 100 by operating the engine key of the vehicle and the microcomputer 10 is activated, the microcomputer 10 starts processing from step S11 shown in FIG.

  In step S11, the microcomputer 10 automatically identifies whether or not it is the first process. In the present embodiment, unprocessed information D1 assigned as data (or flag) indicating whether or not the initial process is in the unprocessed state is provided on the nonvolatile storage unit 21. The unprocessed information D1 is initialized to an “unprocessed” state when the vehicle instrument 100 is shipped from the factory, for example.

  Therefore, the microcomputer 10 grasps whether or not it is the first process by referring to the contents of the unprocessed information D1 on the nonvolatile storage unit 21 in step S11. If the unprocessed information D1 is in the “unprocessed” state, that is, the first process after factory shipment, the process proceeds to the next step S12, and if it is in the “processed” state, the process proceeds to step S13.

  In step S12, the microcomputer 10 of the vehicle meter 100 performs a process for determining a source of various information necessary for display from among a plurality of candidates.

  For example, the location of the latest vehicle speed information can be obtained from a route acquired by CAN communication from another electronic control unit via a network on the vehicle, and a speed pulse input directly from a predetermined sensor via the interface 25. If there is a route to be acquired based on the signal, any of these candidates can be selected as the acquisition source.

  Further, as for the location of obtaining the latest information on the engine rotational speed, a route acquired by CAN communication from another electronic control unit via a network on the vehicle, and an engine directly input from a predetermined sensor via the interface 26 If there is a path to be acquired based on the signal of the rotation speed pulse, any of these candidates can be selected as the acquisition destination.

  In addition, the latest fuel remaining amount information is also directly input from the FUEL sender 28 via the signal input circuit 29 and the route acquired by CAN communication from other electronic control units via the network on the vehicle. If there is a path to be acquired based on the analog signal voltage to be acquired, any of these candidates can be selected as the acquisition destination.

  Selection information D2 indicating the current selection state is provided on the non-volatile storage unit 21 for such information acquisition destination. That is, the selection information D2 indicates which of a plurality of candidates is selected for each of the vehicle speed information acquisition source, the engine rotation speed information acquisition source, the fuel remaining amount information acquisition source, and the like.

  In the present embodiment, the vehicle speed information is obtained from the first route acquired by CAN communication from the other electronic control unit via the network on the vehicle, and directly input from a predetermined sensor via the interface 25. It is assumed that the second path obtained based on the speed pulse signal can exist.

  Therefore, the content of the selection information D2 held by the nonvolatile storage unit 21 is acquired by the first information (vehicle speed information obtained by CAN communication) acquired by the first route and the second route. This indicates which of the second information (vehicle speed calculated based on the pulse of the sensor output) is selected. In the present embodiment, the selection information D2 is assigned to the state in which the first information is selected in the initial state at the time of factory shipment.

  In step S13 of FIG. 2, the microcomputer 10 executes a predetermined instrument display process. That is, data collection such as vehicle speed, engine rotation speed, fuel remaining amount, cooling water temperature, various warning information (warning), and travel distance is repeated, and display of each part is controlled to reflect the latest measurement result.

  Further, when collecting the vehicle speed information, the first information or the second information is collected according to the content of the selection information D2 currently held in the nonvolatile storage unit 21. That is, when the information representing the selection of the first information is held as the selection information D2, the target vehicle speed is selected from the information input to the CAN communication circuit 10c via the communication network on the vehicle and the interface 24. Information is extracted and acquired to obtain the latest measured value. Further, when information indicating the selection of the second information is held as selection information D2, the speed pulse input to the input port P3 is monitored, and the number of pulses appearing within a predetermined time or the pulse The vehicle speed is obtained by calculation based on the generation period, and this is used as the latest measured value.

<Detailed description of input setting processing routine>
Details of the input setting process (S12) shown in FIG. 2 are shown in FIG. The process shown in FIG. 3 will be described below.

  In step S21, the microcomputer 10 switches the instrument display to the non-display state. Thus, while the input setting process shown in FIG. 3 is being executed, the speedometer display unit 11, the tachometer display unit 12, the fuel remaining amount display unit 13, the water temperature meter display unit 14, and the distance meter display unit 17 Is not displayed. That is, display of abnormal measurement values that may occur temporarily during processing is prohibited.

  In step S22, the microcomputer 10 obtains an elapsed time from the start of the process of FIG. 3, and compares this elapsed time with a predetermined time Tmax. This time Tmax corresponds to the maximum value of the time required to determine the acquisition destination of the target information, and is set to 10 seconds, for example. If the time of Tmax has not elapsed, the process proceeds from S22 to S23, and if it has elapsed, the process proceeds to step S29.

  In step S23, the microcomputer 10 communicates with the CAN communication network of the vehicle using the CAN communication circuit 10c, and tries to acquire vehicle speed information from another electronic control unit. When vehicle speed information cannot be acquired as CAN communication data, the process proceeds from S23 to S24, and when vehicle speed information can be acquired, the process proceeds to S29.

  In step S24, the microcomputer 10 monitors the state of the input port P3, and identifies the presence / absence of a speed pulse input. If even one pulse can be detected, the process proceeds from S24 to S25, and if it cannot be detected, the process returns to S22.

  In step S25, the microcomputer 10 obtains an elapsed time after detecting the pulse in step S24, and compares this time with a predetermined time T1. This time T1 is a threshold value for distinguishing a normal continuous pulse train from a single pulse such as noise, and is set to 1 second, for example. If the time T1 has not elapsed, the process proceeds from S25 to S26, and if it has elapsed, the process returns to S22.

  In step S26, the microcomputer 10 identifies the presence or absence of the next pulse following the pulse detected in S24. That is, it is identified whether or not a pulse train that appears continuously appears at the input port P3. If a pulse is detected, the process proceeds from S26 to S27, and if not detected, the process returns to S25.

  In step S27, the microcomputer 10 measures the length of the pulse period of the speed pulse input to the input port P3, and calculates the measured value of the vehicle speed from this period. Then, the measured value is compared with a predetermined threshold value V1. This threshold value V1 is used to prevent sudden display of a large measured value due to switching of information source selection. As a specific example of the threshold value V1, it is assumed to be set to 10 km / h, for example. If the measured value is less than or equal to V1, the process proceeds from S27 to S28, and if it exceeds V1, the process returns to S22.

  In step S28, the microcomputer 10 switches to a state in which the input port P3 is selected as the vehicle speed information acquisition destination. In other words, the content of the selection information D2 held in the nonvolatile storage unit 21 is a state in which data obtained by CAN communication is selected in the initial state, but the content of the selection information D2 is rewritten and the content of the input port P3 is changed. Change to selected state.

  In step S29, the microcomputer 10 updates the content of the above-mentioned unprocessed information D1 held in the non-volatile storage unit 21 so as to be processed.

  In step S30, the microcomputer 10 cancels the non-display state of the instrument display switched in step S21 described above.

<Description of overall operation>
When the vehicle instrument 100 in the initial state immediately after shipment from the factory is assembled in the vehicle and the vehicle instrument 100 is turned on, the content of the unprocessed information D1 is unprocessed in step S11 of FIG. As a result, the input setting process in step S12 is executed.

  Thus, if the speed pulse is input to the input of the interface 25, the selection state of the acquisition destination of the vehicle speed information is “based on the speed pulse of the input port P3” from “the route for acquiring data by CAN communication”. Automatically switch to “Obtain route”. If the speed pulse is not input to the input of the interface 25, the selection state remains “path for acquiring data by CAN communication” even if the input setting process of step S12 is executed.

  When the input setting process in step S12 is executed once, the content of the unprocessed information D1 is rewritten to “processed” in step S29. Therefore, when the vehicle instrument 100 is turned on again thereafter, the process proceeds from step S11 to S13, and the input setting process is not executed. That is, the input setting process is executed only once.

  Further, when acquiring the latest measurement value in step S13, the acquisition destination of the necessary information can be immediately specified by the contents of the selection information D2 on the nonvolatile storage unit 21, so that the time shown in the process shown in FIG. This processing is not necessary, and the processing load on the microcomputer 10 is small. Therefore, it is possible to shorten the time required from when the power is turned on until the instrument display is started, and the response from when the actual vehicle speed changes until the instrument display is updated is accelerated.

  Even after the above-described input setting process has already been executed and the unprocessed information D1 becomes “processed”, the input setting process may need to be executed again for some reason for switching the selection state. Conceivable. In such a case, it is necessary to forcibly return the unprocessed information D1 to the “unprocessed” state. Such an operation is performed by, for example, directly rewriting the contents of the nonvolatile storage unit 21 by manual input, or by giving a predetermined command to the microcomputer 10 and returning the unprocessed information D1 to the initial state under the control of the microcomputer 10. Is assumed.

<Expected modification>
In the input setting process shown in FIG. 3, it is assumed that the vehicle speed information source is determined. However, the engine speed information, the remaining fuel information, the cooling water temperature information, etc. The acquisition destination can be determined from a plurality of candidates.

  In addition, in the input setting process shown in FIG. 3, it is assumed that CAN communication data is selected in the initial state as the vehicle speed information acquisition destination. However, the input port P3 is selected in the initial state. The processing may be changed so that the selected state can be switched from the state to the data of CAN communication.

  Further, in the input setting process shown in FIG. 3, it is assumed that input by CAN communication and pulse input from a sensor can exist as a plurality of routes from which vehicle speed information is obtained. It is also conceivable to apply this process to the selection. For example, when a sensor that outputs an analog signal and a sensor that outputs a digital signal can be selected as a sensor that outputs a fuel remaining amount signal, either an analog signal input path or a digital signal input path It is assumed that processing is performed so as to select one of them.

  In addition, the vehicle instrument 100 shown in FIG. 1 is assumed to be connected to a vehicle-side communication network by CAN communication, but has been changed to perform communication of other communication formats such as LIN, BEAN, etc. You may do it.

<Advantages of vehicle instrument 100>
As described above, the vehicle instrument 100 can automatically select a source of measurement value information such as the vehicle speed from a plurality of candidates, and therefore, a plurality of types of instruments need not be prepared individually. However, it can handle various variations of vehicles. Moreover, the above-described input setting process is executed only once after factory shipment, and the input setting process is not executed in a situation where the vehicle instrument 100 is normally used. Therefore, the processing load of the microcomputer 10 that controls the vehicle instrument 100 is reduced, the time required for starting up the display of the measured value after the power is turned on is shortened, and the response of the instrument display is delayed. Absent.

  In addition, when the source of the information on the measured value such as the vehicle speed is switched, the display value is rapidly changed by switching only when the measured value satisfies a predetermined condition or less as in step S27 of FIG. Can be prevented, and the user does not feel uncomfortable.

10 Microcomputer (Measurement value selection control unit, selection information determination unit)
10a Read only memory 10b Random access memory 10c CAN communication circuit 10d A / D conversion circuit 11 Speedometer display section (display section)
DESCRIPTION OF SYMBOLS 12 Tachometer display part 13 Fuel fuel gauge display part 14 Water temperature meter display part 15,16 Motor driver 17 Distance meter display part 18 Light source for illumination 19 Warning display part 21 Nonvolatile memory | storage part (nonvolatile information storage part)
22 power supply circuit 23 interface 24 interface (first signal input unit)
25 interface (second signal input section)
26 Interface 27 Operation switch 28 FUEL sender 29 Signal input circuit 100 Instrument for vehicle

Claims (5)

A vehicle instrument that displays information representing at least one measurement value,
For a specific measurement target, a display unit that displays the measurement value;
A first signal input unit for inputting first information corresponding to a measurement value of the measurement object;
A second signal input unit for inputting second information corresponding to the measurement value of the measurement object;
A measurement value selection control unit that selects one of the first information and the second information and displays a measurement value of the selected information on the display unit;
Non-volatile information for holding selection information indicating the selection state of the first information or second information in the measurement value selection control unit and unprocessed information indicating whether or not a predetermined selection switching process is in an unprocessed state A storage unit;
Only when the unprocessed information is in an unprocessed state, a selection information determination unit that executes the selection switching process, reflects the result in the selection information, and updates the unprocessed information to processed,
A vehicle instrument comprising: When at least one of the first information and the second information is input as a pulse signal, the selection information determination unit recognizes it as an effective pulse signal only when a plurality of pulses are detected within a predetermined time. Select the information you want to
The vehicle instrument according to claim 1. The selection information determination unit is a pulse signal that is effective only when a period of a detected pulse satisfies a predetermined condition when at least one of the first information and the second information is input as a pulse signal. Recognize and select relevant information,
The vehicle instrument according to claim 1. The selection information determination unit selects corresponding information only when the measurement value of the first information or the second information is equal to or less than a predetermined value, and ends the selection switching process.
The vehicle instrument according to claim 1. The selection information determining unit controls the display unit to a non-display state when executing the selection switching process.
The vehicle instrument according to claim 1.

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