JP2013043458A - On-vehicle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an on-vehicle device capable of minimizing an increase in the size of the device by preventing the operation of the device from being interrupted for a long time even if an engine is started during the operation when a hard disk device having a write cache memory is used.SOLUTION: This on-vehicle device 100 includes a hard disk device 30 allowing the designation of use/nonuse of the write cache memory 34, a product microcomputer section 10, a power supply circuit 60 for supplying an operation power to the hard disk device 30, a power supply circuit 62 to which a booster circuit 64 is connected and which supplies an operation power to the product microcomputer section 10, and a CPU 12 serving as a CM control section which instructs the unuse of the write cache memory 34 to the hard disk device 30 before the start of the engine and also instructs the use of the write cache memory 34 to the hard disk device 30 after the start of the engine.

Description

  The present invention relates to an in-vehicle device that is mounted on a vehicle and reads / writes various data from / to a hard disk device.

  2. Description of the Related Art Conventionally, an in-vehicle navigation device that reads map data stored in a hard disk device and performs processing such as map display is known (for example, see Patent Document 1). A write cache memory is used in the hard disk device provided in the navigation device, and the time for writing data is shortened. In this hard disk device, the map data for each fiscal year is updated by connecting an external hard disk device. When data stored in the external hard disk device is written to the built-in hard disk device, the power The display that disables the power off is performed, or the power is not controlled to be turned off.

Japanese Patent Laying-Open No. 2007-249813 (page 7-13, FIG. 1-6)

  In recent years, hard disk devices are widely used as storage devices for devices mounted on vehicles as well as navigation devices. For example, by storing music data ripped from a CD or the like in an audio device in a hard disk device, a large amount of music data can be stored. In such a hard disk device, as described in Patent Document 1, data can be efficiently written by using a write cache memory.

  By the way, if the power is turned off while data is being written to such a hard disk device, not only an error occurs in the data writing to the physical magnetic disk, but also a large amount already stored in the write cache memory. Data will be lost. In the navigation device disclosed in Patent Document 1, display and control are performed so that the user does not turn off the power and this occurs. However, considering the case where the operation of the navigation device is started before the engine is started and then the engine is started, the battery voltage may be reduced when the engine is started, and the operation of the navigation device may be reset. In such a case, since the built-in hard disk device is also reset, the data already stored in the write cache memory is lost, and the operation of the navigation device is interrupted for a long time.

  In order to avoid such a situation, a battery for driving a vehicle-mounted device using a hard disk device such as a navigation device is separated from a battery for an engine starter, or is boosted between the battery and the vehicle-mounted device. A method of providing a circuit so that the in-vehicle device is not reset due to a voltage drop is conceivable. However, when two batteries are provided, the cost increases and the weight increases, which is contrary to the recent demand for weight reduction. Further, when a booster circuit is provided to prevent reset due to a voltage drop of the battery, the operating power of the entire in-vehicle device including the hard disk device having a mechanical drive unit is secured, and the device scale of the booster circuit is increased. growing.

  As described above, in a vehicle-mounted device using a hard disk device having a write cache memory as a storage device, the operation is interrupted for a long time when the engine is started in the middle of the operation. There is a problem that the scale of the device becomes large due to the need for a booster circuit for the capacitance.

  The present invention was created in view of the above points, and its purpose is to use a hard disk device having a write cache memory as a storage device, and to operate for a long time even if the engine is started during operation. An object of the present invention is to provide a vehicle-mounted device that can be kept from being interrupted and can minimize the expansion of the device scale.

  In order to solve the above-described problems, an in-vehicle device of the present invention includes a write cache memory, a hard disk device capable of specifying use / nonuse of the write cache memory when writing data to a storage medium, and a predetermined program , A program execution unit that performs a predetermined operation while reading / writing data from / to the hard disk device, a first power supply circuit that is connected to the battery and supplies operating power to the hard disk device, and a program execution unit A second power supply circuit that supplies operating power to the battery, a booster circuit that boosts and supplies the second power supply circuit when the voltage of the battery drops, and the hard disk drive that prevents the use of the write cache memory before starting the engine. To the hard disk drive to use the write cache memory after the engine is started. And a cache memory use state instruction means for instructing Te.

  Before starting the engine, data is written to the storage medium without using the write cache memory. Therefore, even if the operating voltage drops and the hard disk drive is reset when the engine starts, the data that is currently being written Writing can be resumed. In addition, since the program execution means uses a booster circuit to prevent a decrease in operating voltage when starting the engine, normal operation can be continued even when the engine is started. As a result, it is possible to prevent the operation from being interrupted for a long time even if the engine is started during the operation. Furthermore, by removing the hard disk device from the target for maintaining the operating voltage using the booster circuit, a small-capacity booster circuit can be used, and the scale of the device can be minimized.

  Further, it is desirable that the above-described cache memory use state instruction means is included in the program execution means. As a result, the operation of the cache memory use state instruction means can be realized only by adding a program, and the operation can be continued even when the engine is started.

  The program execution means described above preferably includes at least one of a ROM and a RAM that store the program, and a CPU that reads and executes the program from the ROM or RAM. In particular, it is desirable that the program execution means described above does not include a mechanical drive unit. Thereby, the operating power supplied by the booster circuit can be reduced.

  Further, it is desirable that the cache memory use state instructing unit mentioned above instructs the hard disk device to use the write cache memory when receiving an engine start signal indicating that the engine has been started from an external device. Thereby, it can know reliably and easily that the engine started.

  Moreover, it is desirable that the hard disk device and the program execution means described above start operation at a predetermined timing before starting the engine. Specifically, the predetermined timing described above is preferably when the vehicle door is opened or closed, or when the vehicle door is unlocked. Thereby, operation | movement is started by starting an engine, time until a user can utilize a vehicle-mounted apparatus can be shortened, and operativity can be improved.

  Further, it is desirable that the cache memory use state instructing unit mentioned above instructs the hard disk device not to use the write cache memory when the engine stop is detected. Thus, it is possible to prepare for a case where the engine is restarted after being stopped.

  Further, it is desirable that the above-described cache memory use state instructing means instructs the hard disk device not to use the write cache memory when idling is stopped. As a result, it is possible to prevent the operation from being interrupted for a long time when the engine is started next time when idling is stopped.

  The program executed by the program execution means described above preferably includes a navigation program that guides the running of the vehicle using map data stored in the hard disk device. Alternatively, it is desirable that the program executed by the above-described program execution means includes an audio program that reproduces music using music data stored in the hard disk device. The program executed by the program execution means described above preferably includes a broadcast reception program for storing data received by the receiver in the hard disk device. The program executed by the program execution means described above preferably includes a drive recorder program that stores image data obtained by imaging the surroundings of the vehicle in a hard disk device. Particularly in these in-vehicle devices that are considered to use a hard disk device in particular, the effect of preventing the operation from being interrupted for a long time even when the engine is started during the operation is great.

It is a figure which shows the whole vehicle-mounted apparatus structure of one Embodiment. It is explanatory drawing which shows operation | movement in the case of starting a vehicle-mounted apparatus prior to engine starting, when boarding a vehicle. It is explanatory drawing which shows operation | movement in the case of restarting after stopping an engine by idling stop control.

  Hereinafter, an in-vehicle device according to an embodiment to which the present invention is applied will be described with reference to the drawings. FIG. 1 is a diagram illustrating an overall configuration of an in-vehicle device according to an embodiment. 1 includes a product microcomputer unit 10, a hard disk device (HDD) 30, a GPS device 40, a disk device 42, a receiver 44, a camera 46, a communication interface unit (communication IF) 50, and power supply circuits 60 and 62. The booster circuit 64 is included.

  The product microcomputer section 10 performs a predetermined operation while reading / writing data from / to the hard disk device 30 by executing a predetermined program. The product microcomputer unit 10 corresponds to the program execution means, and is configured without including a mechanical drive unit. The product microcomputer unit 10 includes a CPU 12, a ROM 14, a RAM 16, and a flash ROM 18. The flash ROM 18 is a flash memory that stores a basic program for operating the in-vehicle device 100 as a computer and various application programs for operating as a navigation device. For example, the flash ROM 18 stores a file system 21, HDD control driver 22, CM control program 23, navigation application 24, audio application 25, recording application 26, and recording application 27.

  The file system 21 manages data to be read from and written to the hard disk device 30. The HDD control driver 22 drives the hard disk device 30 to read / write data. The CM (cache memory) control program 23 is for instructing the hard disk device 30 to use / not use the built-in write cache memory before and after the engine is started. When the CM control program 23 is executed by the CPU 12, an operation as a CM control unit (corresponding to a cache memory use state instruction unit) is performed.

  The navigation application 24 is a navigation program that uses the map data stored in the hard disk device 30 to guide traveling of the vehicle on which the in-vehicle device 100 is mounted. The navigation device is used together with the GPS device 40 that detects the position of the host vehicle and guides the travel of the vehicle, such as map display, route search / guidance, and peripheral facility search.

  The audio application 25 is an audio program that reads music data stored in the hard disk device 30 and music data recorded on a CD or DVD and reproduces the music. Reading of music data recorded on a CD or the like is performed using the disk device 42. The disk device 42 reads music data recorded on a CD or DVD as a disk type recording medium. The music data can be directly played back using the audio application 25, but can also be written once in the hard disk device 30 to form a database together with other music data, and read out from the hard disk device 30 and played back as necessary.

  The recording application 26 is a received data recording program that records image data received by the receiver 44 in the hard disk device 30. The receiver 44 receives image data and audio data of a program distributed from a broadcasting station, and performs display and audio output. These received data can be stored in the hard disk device 30 (program recording) as required (according to the contents set by the user), and the recording application 26 is executed by the CPU 12 to perform this recording. Operation is performed.

  The recording application 27 is an imaging data recording program for performing an operation as a drive recorder that records image data obtained by imaging the surroundings of the vehicle using the camera 46 in the hard disk device 30. The camera 46 is installed at a predetermined position of the vehicle (for example, a position in front of the vehicle and a room mirror and a door mirror can be seen), and image data obtained by imaging by the camera 46 by executing the recording application 27 by the CPU 12. Is recorded on the hard disk device 30 for the latest predetermined time (for example, several minutes).

  The hard disk device 30 is a storage device that reads and writes data as necessary when executing the navigation application 24 stored in the flash ROM 18 and performing operations corresponding to each application. A cache memory 34 and an HDD control unit 36 are provided. The writing disk unit 32 is a recording medium that reads and writes data using a magnetic head (not shown). The write cache memory 34 has a predetermined capacity and temporarily holds data before writing the data to the write disk unit 32. By using the write cache memory 34, the data writing efficiency can be increased, and the time required for data writing can be shortened. The HDD control unit 36 controls writing and reading of data with respect to the writing disk unit 32. When writing data, use / non-use of the write cache memory 34 can be designated from the outside (for example, the CPU 12 executing the CM control program 23), and the HDD control unit 36 directly writes the input data to the disk. Write control is performed in which the data is recorded in the unit 32 or once stored in the write cache memory 34 and then read out and recorded in the write disk unit 32.

  The communication interface unit 50 transmits and receives signals to and from an engine ECU (electronic control unit) 210 and an ISS (idle stop system) 220 as external devices. The engine ECU 210 controls the engine 200. In this embodiment, it is assumed that an engine start signal is output from engine ECU 2210 after the engine is started. The engine start signal is received by the communication interface unit 50 so that the vehicle-mounted device 100 (CM control unit) can know that the engine has been started. Note that the engine start may be detected by using a method other than receiving the engine start signal. For example, the case where the engine start is detected by monitoring the voltage of the vehicle-mounted battery 300 can be considered.

  In addition, the ISS 220 performs an idling stop control that stops the engine 200 when the vehicle stops due to a signal or the like and satisfies a predetermined condition (for example, the remaining battery level is equal to or greater than a predetermined value). In this embodiment, it is assumed that an IS (idling stop) signal is output from the ISS 220 immediately after the engine is stopped by the idling stop control. This ISS signal is received by the communication interface unit 50 so that the in-vehicle device 100 (CM control unit) can know that the engine 200 has been stopped by idling stop control. The engine stop may be detected by a method other than receiving the ISS signal. For example, since the engine ECU 210 controls the start and stop of the engine 200, the engine ECU 210 outputs a signal indicating that the engine 200 has been stopped, and receives the signal through the communication interface 50 to stop the engine 200 in the in-vehicle device 100. You may let you know what you did.

  A power supply circuit (first power supply circuit) 60 is connected to a battery 300 and generates, for example, an operating voltage (constant voltage) of 5 V, and includes a hard disk device 30, a GPS device 40, a disk device 42, a receiver 44, and a camera. 46, operating power is supplied to each of the communication interface units 50.

  The power supply circuit 62 (second power supply circuit) generates an operating voltage (constant voltage) of 3.3 V, for example, and supplies operating power to the product microcomputer unit 10. A battery 300 is connected to the power supply circuit 62 via a booster circuit 64. The booster circuit 64 boosts the voltage of the battery 300 and supplies the boosted voltage to the power supply circuit 62. By passing through the booster circuit 64, even when the voltage of the battery 300 is greatly reduced when the engine 200 is started, fluctuations in the voltage applied to the power supply circuit 62 can be reduced, and the output voltage ( 3.3V) can be maintained. On the other hand, since the battery 300 is directly connected to the power supply circuit 60, if the voltage of the battery 300 greatly decreases when the engine 200 is started, the output voltage of the power supply circuit 60 also temporarily decreases and is connected to the power supply circuit 60. The hard disk device 30 or the like is reset.

  The in-vehicle device 100 of this embodiment has such a configuration, and the operation thereof will be described next. FIG. 2 is an explanatory diagram showing an operation when the vehicle-mounted device is activated prior to starting the engine when boarding the vehicle. In FIG. 2, “HDD” indicates the use state of the write cache memory of the hard disk device 30, and “cache off” indicates that data is written without using the write cache memory 34. “On” indicates that data is written using the write cache memory 34.

  The vehicle-mounted device 100 is activated when a vehicle door (for example, a door on the driver's seat side) is opened and closed. Thereafter, each component of the in-vehicle device 100 starts operating. In addition, as a method for the vehicle-mounted device 100 to detect the opening / closing of the door, a signal notifying the opening / closing of the door is used when using an opening / closing sensor (not shown) or from the engine ECU 210 or an ECU (not shown) that controls the entire vehicle. The case where it receives is considered. Further, instead of starting the in-vehicle device 100 when the door is opened and closed, the in-vehicle device 100 may be started when the door is unlocked.

  When the in-vehicle device 100 is activated, the CM control unit (the CPU 12 executing the CM control program 23) instructs the hard disk device 30 not to use the write cache memory 34. In the hard disk device 30 that has received this instruction, when a data write request occurs, the HDD control unit 36 writes data without using the write cache memory 34. For example, as a specific example in the case where a data write request occurs before the engine is started, when the navigation application 24 is executed to perform a route search, the audio application 25 is executed and the CD or the like loaded in the disk device 42 is used. When ripping music data, the recording application 26 is executed to record a program received by the receiver 44, the recording application 27 is executed and the image data captured by the camera 46 is recorded.

  When the engine 200 is started in such a state, the output voltage of the power supply circuit 60 directly connected to the battery 300 decreases, so the hard disk device 30 is temporarily reset. At this stage, the write cache memory 34 is reset. Is not used, an error occurs in the writing process at the time of resetting, but the operation using the hard disk device 30 can be continued only by rewriting the data in error after the resetting. Even when the engine 200 is started, since the normal operating voltage is maintained from the power supply circuit 62 to the product microcomputer unit 10, the operation of the product microcomputer unit 10 continues normally.

  When an engine start signal is output from engine ECU 210 after the engine is started, the CM control unit instructs hard disk device 30 to use write cache memory 34. Thereafter, the HDD control unit 36 of the hard disk device 30 writes data using the write cache memory 34.

  Thus, in the in-vehicle device 100 of the present embodiment, since the data is written to the storage medium (the writing disk portion 32) without using the write cache memory 34 before the engine is started, the operating voltage is reduced when the engine is started. Even if the hard disk device 30 is reset, writing can be resumed immediately from the data currently being written. Further, since the product microcomputer unit 10 uses the booster circuit 64 to prevent the operating voltage from being lowered when the engine is started, normal operation can be continued even when the engine is started. Thus, it is possible to avoid the operation of the product microcomputer unit 10 being interrupted for a long time even when the engine 200 is started during the operation. Furthermore, by removing the hard disk device 30 from the target for maintaining the operating voltage using the booster circuit 64, the small-capacity booster circuit 64 can be used, and expansion of the device scale can be minimized.

  Further, by realizing the CM control unit (cache memory use state instructing means) using the product microcomputer unit 10, it is possible to realize a necessary operation only by adding the CM control program 23, and at the time of engine start-up. Can continue to operate.

  Further, the engine start is detected based on the engine start signal sent from the engine ECU 210 to instruct the hard disk device 30 to use the write cache memory 34, and the engine is started by using the engine start signal. You can know this reliably and easily.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. For example, in the above-described embodiment, the CM control unit (cache memory use state instruction unit) is realized by using the product microcomputer unit 10, but a CM control unit may be provided separately from the product microcomputer unit 10. Since this CM control unit only needs to be able to instruct the hard disk device 30 to use the write cache memory 34 after the engine is started, the CM control unit may be operated by the power supplied from the power supply circuit 60. Further, the CM control unit may be built in the hard disk device 30.

  In the above-described embodiment, the navigation application 24, the audio application 25, the recording application 26, and the recording application 27 are provided. However, the in-vehicle device 100 does not necessarily need to include all these four applications, and one or more of them are included. You may make it selectively provide suitably. If the hard disk device 30 is used, application programs other than these four applications may be stored in the flash ROM 18 and executed by the CPU 12. Further, although the flash ROM 18 is used, other non-volatile memory, RAM that performs power backup (the power supply circuit 62 can be used), or the like may be used instead.

  In the above-described embodiment, the case where the write cache memory 34 of the hard disk device 30 is set to be unused before boarding the vehicle and starting the engine has been described. However, even when the engine is stopped by the idling stop control. The present invention can be applied.

  FIG. 3 is an explanatory diagram showing an operation when the engine is restarted after being stopped by the idling stop control. Unlike the case shown in FIG. 2, when the engine is stopped and then restarted by idling stop control, the in-vehicle device 100 is in an operating state.

  When the communication interface unit 50 receives the IS signal output from the ISS 220 after the engine is stopped by the idling stop control, the CM control unit (the CPU 12 that has executed the CM control program 23) sends the write cache memory to the hard disk device 30. 34 is not used. In the hard disk device 30 that has received this instruction, when a data write request occurs, the HDD control unit 36 writes data without using the write cache memory 34.

  When the engine 200 is restarted in such a state, the output voltage of the power supply circuit 60 directly connected to the battery 300 decreases, so the hard disk device 30 is temporarily reset. At this stage, the write cache memory Since 34 is not used, an error occurs in the writing process at the time of resetting, but the operation using the hard disk device 30 can be continued only by rewriting the data in error after the resetting. Even when the engine 200 is restarted, since the normal operating voltage is maintained from the power supply circuit 62 to the product microcomputer unit 10, the operation of the product microcomputer unit 10 continues normally.

  When an engine start signal is output from engine ECU 210 after engine restart, the CM control unit instructs hard disk device 30 to use write cache memory 34. Thereafter, the HDD control unit 36 of the hard disk device 30 writes data using the write cache memory 34.

  Thus, even if the engine is stopped and restarted by the idling stop control, it is possible to avoid the operation of the product microcomputer unit 10 being interrupted for a long time.

  As described above, according to the present invention, it is possible to prevent the operation of the product microcomputer unit 10 from being interrupted for a long time even if the engine 200 is started during the operation. Further, by removing the hard disk device 30 from the target for maintaining the operating voltage using the booster circuit 64, the small-capacity booster circuit 64 can be used, and the expansion of the device scale can be minimized.

10 Product microcomputer section 12 CPU
14 ROM
16 RAM
18 Flash ROM
30 Hard Disk Drive (HDD)
32 Write disk unit 34 Write cache memory 36 HDD control unit 40 GPS device 42 Disk device 44 Receiver 46 Camera 50 Communication interface unit (communication IF)
60, 62 Power supply circuit 64 Booster circuit 100 In-vehicle device 200 Engine 210 Engine ECU (electronic control unit)
220 ISS (idle stop system)

Claims (13)

A hard disk device having a write cache memory and capable of designating use / non-use of the write cache memory when writing data to a storage medium;
Program execution means for performing a predetermined operation while reading / writing data from / to the hard disk device by executing a predetermined program;
A first power supply circuit connected to a battery and supplying operating power to the hard disk drive;
A second power supply circuit for supplying operating power to the program execution means;
A booster circuit that boosts and supplies the voltage to the second power supply circuit when the voltage of the battery drops;
Cache memory use state instruction means for instructing the hard disk device not to use the write cache memory before starting the engine, and for instructing the hard disk device to use the write cache memory after starting the engine;
A vehicle-mounted device comprising: In claim 1,
The in-vehicle apparatus characterized in that the cache memory use state instruction means is included in the program execution means. In claim 1 or 2,
The on-vehicle apparatus, wherein the program execution means includes at least one of a ROM and a RAM for storing a program, and a CPU for reading and executing the program from the ROM or the RAM. In claim 3,
The on-vehicle apparatus characterized in that the program execution means does not include a mechanical drive unit. In any one of Claims 1-4,
The cache memory use state instructing unit instructs the hard disk device to use the write cache memory when receiving an engine start signal indicating that the engine has been started from an external device. apparatus. In any one of Claims 1-5,
The hard disk device and the program execution means start an operation at a predetermined timing before starting the engine. In claim 6,
The vehicle-mounted device characterized in that the predetermined timing is when the door of the vehicle is opened or closed, or when the locked state of the vehicle door is released. In any one of Claims 1-7,
The on-vehicle apparatus characterized in that the cache memory use state instructing means instructs the hard disk device not to use the write cache memory when detecting engine stop. In any one of Claims 1-7,
The on-vehicle device characterized in that the cache memory use state instructing unit instructs the hard disk device not to use the write cache memory when idling is stopped. In any one of Claims 1-9,
The in-vehicle device characterized in that the program executed by the program execution means includes a navigation program for guiding the running of the vehicle using map data stored in the hard disk device. In any one of Claims 1-10,
The in-vehicle apparatus characterized in that the program executed by the program execution means includes an audio program for playing music using music data stored in the hard disk device. In any one of Claims 1-11,
The in-vehicle apparatus characterized in that the program executed by the program executing means includes a received data recording program for recording data received by a receiver in the hard disk device. In any one of Claims 1-12,
The in-vehicle apparatus characterized in that the program executed by the program execution means includes an imaging data recording program for recording image data obtained by imaging around the vehicle on the hard disk device.

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