JP2017117322A - Electronic equipment, control method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide electronic equipment in which writing of data into a storage medium and communication of data read out from the storage medium by wireless LAN do not occur concurrently, and to provide a control method and a program.SOLUTION: According to an embodiment, electronic equipment installed in a mobile body includes communication means, a non-volatile semiconductor memory, and a processing unit for writing data into the semiconductor memory. The communication means is connected with communication equipment by radio, and transmits data to the communication equipment or receives data from the communication equipment. The semiconductor memory stores data to be transmitted to the communication equipment. The processing unit stops transmitting data to the communication equipment or receiving data from the communication equipment according to a movement situation of the mobile body.SELECTED DRAWING: Figure 3

Description

  Embodiments of the present invention generally relate to an electronic device installed in a moving body, which includes a nonvolatile storage medium and includes a wireless communication function, a control method thereof, and a program.

  One example of such a conventional electronic device is a drive recorder that records the driving situation of an automobile. For example, the drive recorder records speed data that changes with time as an example of the driving situation. In recent years, drive recorders record not only numerical data such as speed but also scenery viewed from the driver's seat. When a car accident occurs, the image data may be useful to know the details of the accident.

  The drive recorder is often shaped like a video camera or the like, and is affixed to the windshield of an automobile using a double-sided tape or the like. The captured image data is stored together with the operation record data in a non-volatile storage medium such as an SD card (registered trademark) installed in the drive recorder or a built-in flash memory.

  Many users may be interested in the scenery seen from the driver's seat taken by the drive recorder, but the drive recorder does not include a display unit for reproducing images. In order to reproduce an image, it is necessary to connect the drive recorder to a personal computer, a smart phone, or the like by a wireless LAN or the like, and to transfer the image data stored in the storage medium to the personal computer, the smart phone, or the like. The transferred image data is displayed on a display screen of a personal computer, a smartphone or the like.

  Thus, in an in-vehicle electronic device such as a drive recorder, image data output from a camera is written to a storage medium via a circuit board (particularly, a connector on the circuit board) and read from the storage medium. The received image data is communicated to another electronic device via the wireless LAN.

JP 2007-158630 A JP 2008-078793 JP 2009-098738 A

  An electronic device mounted on a moving body is required to be small and have low power consumption. At this time, if the writing of the image data to the storage medium and the communication of the data read from the storage medium to the other electronic device by the wireless LAN are simultaneously performed, the writing speed and the reading speed of the storage medium are reduced, This may affect the writing of data to the storage medium.

  An object of one embodiment of the present invention is to provide an electronic device in which writing of data to a storage medium and communication via wireless LAN of data read from the storage medium do not occur at the same time.

  According to the embodiment, the electronic device installed in the mobile body includes a communication unit, a nonvolatile semiconductor memory, and a processing unit that writes data to the semiconductor memory. The communication means is wirelessly connected to the communication device and transmits data to the communication device or receives data from the communication device. The semiconductor memory stores data transmitted to the communication device. The processing unit stops transmission of data to the communication device or reception of data from the communication device according to the moving state of the moving body.

It is a figure which shows an example of the external appearance of the drive recorder of embodiment. It is a block circuit diagram which shows an example of the system configuration | structure of the drive recorder of embodiment. It is a flowchart which shows an example of operation | movement of the drive recorder of embodiment. It is a flowchart which shows an example of an upload / download request interruption. It is a flowchart which shows an example of the state determination operation | movement of a motor vehicle. It is a flowchart which shows the other example of the state determination operation | movement of a motor vehicle. It is a flowchart which shows an example of the power-supply interruption of a drive recorder. It is a flowchart which shows an example of the accident interruption of a drive recorder.

  Hereinafter, embodiments will be described with reference to the drawings. As an embodiment, an electronic device that is installed in a moving body, includes a nonvolatile storage medium, and has a wireless communication function will be described. Examples of the moving body are an automobile, a motorcycle, a train, a ship, an airplane, and the like. Examples of the non-volatile storage medium are, for example, an SD card and a flash memory (built-in memory). An example of the wireless communication function is a wireless LAN function based on, for example, WiFi (registered trademark). The SD card is a removable storage medium including flash memory. In recent years, an SD card with a wireless LAN function including a wireless LAN module in a package has been put into practical use. In the embodiment, an example in which an SD card with a wireless LAN function is used will be described. However, a conventional SD card may be used and a wireless LAN module may be provided in an electronic device. Examples of the electronic device are a drive recorder and a car navigation device, for example. Examples of driving situations are, for example, speed data and image data in front of the driver's seat. Image data photographed by the camera is periodically written in a non-volatile storage medium, and is converted into an image file every predetermined time. The image file can be transmitted to a communication device such as a smartphone via a wireless LAN and displayed on the screen of the smartphone.

  FIG. 1A is a perspective view of the drive recorder 10 as viewed from the front side, and FIG. 1B is a right side view of the drive recorder 10.

  The drive recorder 10 is configured to receive power from an external power source such as a cigarette lighter socket of an automobile, for example. The main body of the drive recorder 10 includes a substantially cylindrical first main body 11, a substantially cylindrical second main body 12, and a rectangular parallelepiped bracket portion 13. The first main body 11 and the second main body 12 each have a cylindrical housing having the same diameter. The second main body 12 is rotatably attached to the first main body 11 so as to rotate around the central axis C along the longitudinal direction of the drive recorder 10. That is, the second main body 12 rotates around the central axis C in a state where the first main body 11 is fixed.

  The second body 12 is provided with a recess 18 formed by cutting a part of the surface of the second body 12. The camera lens 14 is disposed in the recess 18. The recess 18 may have a depth greater than or equal to the thickness of the lens 14. By rotating the second main body 12, the relative position of the lens 14 of the second main body 12 with respect to the first main body 11 can be changed. Thereby, the visual field of the camera can be adjusted.

  The bracket portion 13 functions as an attachment portion for attaching the main body of the drive recorder 10 to the windshield of the automobile. The bracket portion 13 is a box-shaped member having a predetermined thickness, and the bottom surface thereof is fixed to the first main body 11. The bottom surface of the bracket portion 13 may be joined to a flat mounting portion formed on the surface by scraping a part of the surface of the first main body 11. The flat surface of the upper surface of the bracket portion 13 is attached to the windshield of the automobile via a double-sided tape 20.

  Since the bracket portion 13 has a thickness and the lens 14 is disposed in the recess 18 of the second main body 12, the lens 14 is prevented from coming into contact with the windshield when the bracket portion 13 is attached to the windshield of the automobile. The By simply attaching the bracket portion 13 to the windshield, the lens 14 can be positioned in the vicinity of the windshield suitable for photographing.

  The bracket unit 13 may incorporate a GPS antenna or a GPS module including a GPS antenna and a GPS receiver. Since the upper surface of the bracket portion 13 is in contact with the windshield of the automobile, by incorporating the GPS antenna in the bracket portion 13, the GPS antenna is disposed at a position closest to the windshield and the directivity direction of the GPS antenna is automatically set. It can be optimized and can contribute to the improvement of the reception sensitivity of the GPS antenna.

  The GPS antenna (or GPS module) in the bracket portion 13 is connected to the left side surface of the first main body 11 (the left side surface of the main body of the drive recorder 10) via the cable 13A.

  A memory card slot 15 and a power connector 16 are disposed on the right side surface of the second main body 12 (the right side surface of the main body of the drive recorder 10). A memory card, for example, an SD card with a wireless LAN function is inserted into the memory card slot 15. The SD card stores image data taken by the drive recorder 10 and driving record data relating to driving of the automobile obtained by the drive recorder 10. The power connector 16 is connected to an external power source, for example, a cigarette lighter socket of an automobile via a power cable.

  FIG. 2 shows a system configuration of the drive recorder 10.

  The drive recorder 10 is connected to a cigarette lighter socket 32 of an automobile via a power cable connected to the power connector 16. The power connector 16 is connected to a DC / DC converter 34 and a power on / off detector 38. The cigarette lighter socket 32 outputs DC24V or DC12V, and the power on / off determination unit 38 determines whether DC24V or DC12V is output from the cigarette lighter socket 32. The determination result is supplied to the system controller 40. The system controller 40 is configured by a SoC (System on Chip) on which a CPU and hardware logic that realizes functions necessary for controlling the drive recorder are mounted on one semiconductor chip.

  The DC / DC converter 34 steps down the input voltage to about DC5V. The output of the DC / DC converter 34 is input to the charging / power supply switching circuit 36. A large-capacity capacitor 42 is connected to the charge / power supply switching circuit 36. An example of the capacitor 42 is an electric double layer capacitor also called a super capacitor. The charging / power supply switching circuit 36 supplies DC5V to various devices including the system controller 40 and charges the capacitor 42 while DC5V is supplied from the DC / DC converter 34. During a period when DC5V is not supplied from the DC / DC converter 34, the charge / power switching circuit 36 discharges the capacitor 42 and supplies a voltage corresponding to the discharge current to various devices including the system controller 40.

  In this way, the capacitor 42 operates as a standby power source when the external power source is shut off. The standby power supply is not limited to a capacitor, and a battery pack that uses a battery such as a dry battery or a rechargeable battery (such as a lithium ion battery) or a sub power source that uses environmental power generation such as photovoltaic power generation, thermoelectric power generation, vibration power generation, or electromagnetic wave power generation may be used. Good.

  The system controller 40 includes a main memory 44, a nonvolatile memory 52, a double data rate (DDR) SDRAM 54, a camera 56, a card slot 15, a GPS receiver 72, an acceleration sensor 76, a gyro sensor 78, and a wireless communication device (3G device). 82 etc. are connected. The nonvolatile memory 52 stores an operating system (OS) 46, a drive recorder control program, an SD card access control program 48, and the like. When the power is turned on, the OS 46, the drive recorder control program, and the card access control program 48 are loaded into the main memory 46. The system controller 40 executes the OS 46, the control program 48, and the like to access the SD card 62, perform data processing, store image data and operation record data in the SD card 62, and store image data files in the SD card 62. The data is read from the card 62 and transmitted to a mobile terminal such as a smartphone via a wireless LAN.

  The camera 56 includes an image sensor 58 such as a CCD type or a MOS type that captures an image in front of the driver's seat incident on the lens 14. The image sensor 58 can capture not only moving images but also still images. Although not shown, in the case of moving images, a microphone may be provided on the right side surface of the second main body 12 so that sound can be recorded. Recording sounds can also help clarify the cause of an accident if an accident occurs.

  The camera 56 always shoots while the power is on, and image data output from the camera 56 is always written in the SDRAM 54. When there is no free space in the SDRAM 54, the old data is automatically deleted, and the latest image data (for example, image data of a maximum of 30 seconds) is always stored in the SDRAM 54. Data stored in the SDRAM 54 is read periodically, for example, once per second, and stored in the SD card 62. The data read at one time is all the data written in the SDRAM 54. Normally, image data for one second is read every second, and the data in the SDRAM 54 becomes zero once every second. As will be described later, when writing to the SD card is restricted, the amount of data written to the SDRAM 54 is 30 seconds at the maximum. The SD card 62 includes a NAND memory 64, a WiFi module 66, and a CPU 68. The image data written to the SD card 62 is an image file of several minutes, for example, 10 minutes.

  Since the WiFi module 66 of the SD card 62 functions as a wireless LAN access point, the driver uses a wireless LAN to drive a portable recorder (WiFi) module such as a smartphone, a tablet, or a mobile phone (hereinafter referred to as a smartphone) 88 (WiFi module). 66). Note that the mobile terminal does not necessarily have a mobile phone function, and may have a function only connected to the drive recorder via a wireless LAN.

  As a result, the image file stored in the NAND memory 64 can be downloaded to the smartphone 88. Further, the smartphone 88 can receive an update file of a drive recorder control program (application program or firmware) from the Internet. It is also possible to upload an update file of this program from the smartphone 88 to the SD card 62.

  A GPS antenna 74 is connected to the GPS receiver 72. The GPS receiver 72 and the GPS antenna 74 may be provided in the bracket portion 13. In this way, since the bracket portion 13 is in contact with the windshield, the sensitivity of the GPS antenna 74 can be increased. Information indicating the position and moving speed of the GPS receiver 72 can be obtained from the GPS signal received by the GPS receiver 72. The position and moving speed can be obtained based on the Doppler effect of the carrier wave transmitted from the GPS satellite. These pieces of information are stored as driving record data in the SD card 62 together with information representing the acceleration obtained by the acceleration sensor 76 and the angular acceleration obtained by the gyro sensor 78. The wireless communication device 82 is provided to automatically transmit image data and driving status data to a server or the like via a mobile phone line when an accident occurs. The gyro sensor 78 and the wireless communication device 82 can be omitted. Both the GPS receiver 72 and the acceleration sensor 76 are not necessarily provided, and one of them can be omitted.

  In the embodiment, the file is set according to the running / stopped state of the vehicle so that the writing of the image data output from the camera 56 to the SD card 62 and the upload / download of the file with the smartphone 88 are not executed at the same time. Upload / download or wireless LAN connection control. FIG. 3 is a flowchart showing an example of processing of the drive recorder relating to this control.

  When activated, the system controller 40 determines at block 102 whether the status parameter STATUS represents a stop. The determination of the status parameter STATUS will be described later with reference to FIGS. If it is determined that the status parameter STATUS represents stop, there is no problem even if the image data is not stored in the SD card 62 because the image data in front of the driver's seat is not changed. Therefore, in block 104, the system controller 40 stops the function of writing image data from the SDRAM 54 to the SD card 62.

  In block 106, the system controller 40 transmits a command for starting a wireless LAN connection (WiFi connection) between the WiFi module 66 and the smartphone 88 to the SD card 62. In response to this command, the CPU 68 of the SD card 62 transmits a beacon by the WiFi module 66 and establishes a wireless LAN connection with the smartphone 88.

  Since the operation is not hindered even if the smartphone 88 is operated while the automobile is stopped, the driver can request the drive recorder to download an image file from the smartphone 88. When the file download request is received from the smartphone 88, the CPU 68 of the SD card 62 downloads the image file stored in the SD card 62 (NAND memory 64) to the smartphone 88 in block 108. The image file downloaded to the smartphone 88 can be played back on the smartphone 88 and displayed on the screen. Thereby, the scenery seen from the driver's seat photographed with the drive recorder can be seen.

  Wireless LAN connection can also be used for file upload. When downloading the update program for the drive recorder from the Internet to the smartphone 88, the driver can request the drive recorder to upload the update program from the smartphone 88 during the stoppage. When there is an update file upload request from the smartphone 88, the CPU 68 of the SD card 62 receives the update file uploaded from the smartphone 88 in block 108. The system controller 40 updates the program in the nonvolatile memory 52 based on the update file received by the CPU 68. Thereby, the control program of the drive recorder can be uploaded from the smartphone 88. The update program is not limited to uploading from the smartphone 88, but may be downloaded directly from the server to the drive recorder via the wireless communication device 82.

  After the upload / download process in block 108 or when there is no upload / download request, after the wireless LAN connection in block 106, the process returns to block 102 and the determination of the running / stopped state of the vehicle is performed again.

  If the system controller 40 determines that the status parameter STATUS indicates stop, the function of writing image data from the SDRAM 54 to the SD card 62 is stopped in block 104, but the writing function itself is stopped at this stage. It does not have to be. A problem arises when writing image data to the SD card 62 and uploading / downloading a file by the wireless LAN are executed simultaneously. Therefore, even if the block 104 is omitted, the writing of the image data to the SD card 62 may be stopped only while the file is uploaded / downloaded in step 108.

  A flowchart in this case is shown in FIG. If the system controller 40 determines in block 102 that the status parameter STATUS represents stop, in block 106, the system controller 40 issues a command for starting a wireless LAN connection (WiFi connection) between the WiFi module 66 and the smartphone 88 to the SD card 62. Send. In response to this command, the CPU 68 of the SD card 62 transmits a beacon by the WiFi module 66 and establishes a wireless LAN connection with the smartphone 88.

  The system controller 40 determines at block 120 whether to receive an upload / download request from the smartphone 88. If no request is received, block 120 is waited for. If the request is received, the system controller 40 stops the function of writing image data from the SDRAM 54 to the SD card 62 at block 104. In block 108, the CPU 68 of the SD card 62 executes upload / download processing. After the upload / download process in block 108, the process returns to block 102 to determine again whether the vehicle is running / stopped. Note that the function of writing image data to the SD card 62 is enabled again after upload / download processing.

  Note that the blocks 120, 104, and 106 in FIG. 4 also function as upload / download request interrupt processing. That is, it is not performed only after the block 106. If there is an upload / download request at any timing, the upload / download process is executed after the function of writing image data to the SD card 62 is stopped. The

  This reliably prevents the writing of image data to the SD card 62 and the uploading / downloading of files by the wireless LAN from being performed simultaneously.

  Unlike the above-described stop, it is necessary to write image data while traveling. On the other hand, since the operation of the smartphone 88 during driving is not recommended, file upload / download is stopped. However, uploading / downloading of a file is started immediately before the vehicle changes from a running state to a stopped state. When the vehicle is changed, if uploading / downloading is in progress, the uploading / downloading may be preferably completed. Thus, if it is determined at block 102 that the status parameter STATUS does not represent a stop, at block 122, the system controller 40 determines whether a file is being uploaded / downloaded. If upload / download is in progress, block 122 waits until the upload / download is complete.

  When the system controller 40 determines in block 122 that “file upload / download is not in progress”, in block 124, the system controller 40 sends a connection end command to the SD card 62 so as to disconnect the wireless LAN connection (WiFi connection). In response to this command, the CPU 68 of the SD card 62 disconnects the WiFi module 66 and the smartphone 88.

  It should be noted that there is no problem with the state in which the wireless LAN is simply connected during the writing of the image data to the SD card 62. A problem arises in uploading and downloading files over the wireless LAN during the writing of image data to the SD card 62. Therefore, instead of terminating the wireless LAN connection at block 124, the wireless LAN connection is continued, but file uploading and downloading may be prohibited. Specifically, even if a file upload / download request is transmitted from the smartphone 88, the CPU 68 of the SD card 62 may be controlled not to accept the request.

  In block 126, the system controller 40 reads all the image data recorded in the SDRAM 54 and writes it to the SD card 62. In step 124, the wireless LAN connection is terminated or file upload / download is prohibited, so that the image data is written to the SD card 62 without any trouble. At block 128, the system controller 40 determines whether a certain time, eg, 1 second has elapsed after writing. When the predetermined time has elapsed, the system controller 40 reads all the image data recorded in the SDRAM 54 and writes it to the SD card 62 in block 130.

  Thereafter, at block 132, the system controller 40 determines whether the status parameter STATUS represents running. If the status parameter STATUS indicates running, the process returns to block 128, and writing of image data from the SDRAM 54 to the SD card 62 at regular intervals continues. If the status parameter STATUS does not indicate running, the process returns to block 104 and writing from the SDRAM 54 to the SD card 62 stops.

  As described above, uploading and downloading of files by wireless LAN can be performed only when the automobile is stopped, and writing of image data to the SD card 62 is stopped during upload / download. While the vehicle is running, at least file uploading and downloading via the wireless LAN is stopped, and writing from the SDRAM 54 to the SD card 62 is periodically executed. Therefore, writing of image data from the SDRAM 54 to the SD card 62 and downloading of the image file read from the SD card 62 to the smartphone 88 by the wireless LAN or uploading from the smartphone 88 to the drive recorder are not performed at the same time. It is possible to prevent a possibility that the writing speed and reading speed of the SD card 62 are lowered and the writing of the image data to the SD card 62 is affected.

  By disconnecting the wireless LAN connection while traveling, the drive recorder and the portable terminal cannot communicate with each other, so that the portable terminal is not operated during driving, and dangerous actions such as side-view driving can be avoided.

  Two examples of processing for determining the status parameter STATUS will be described with reference to FIGS. These determination processes are always executed when the power is on, that is, when the drive recorder is connected to the cigarette lighter socket 32 via the power cable and the car engine key is in a state other than the lock. The state is always determined.

  In the example of FIG. 5, when the power is turned on in block 142, the system controller 40 initially sets “stop” in the status parameter STATUS in block 144. At block 146, the system controller 40 determines whether a GPS signal can be received. In the embodiment, since the running / stopped state of the automobile is determined using the speed information included in the GPS signal, it is a precondition that the GPS signal can be received. On the other hand, there are situations where GPS signals cannot be received, such as in tunnels. As shown in FIG. 3, during stoppage, writing to the SD card 62 is stopped, and the CPU 68 of the SD card 62 does nothing unless an upload / download request is received. You may judge. Alternatively, if importance is attached to the recording function of the drive recorder, if a GPS signal cannot be received, it is determined that the vehicle is running, upload / download is stopped, and image data may be written to the SD card 62. . The designer of the drive recorder may decide whether to stop or run when the GPS signal cannot be received, but the user may freely select the setting.

  In the embodiment, when the GPS signal cannot be received, it is determined that the vehicle is stopped. Therefore, if it is determined in block 146 that the GPS signal cannot be received, block 146 is executed again and waits until the GPS signal can be received.

  However, the embodiment is not limited to determining the running / stopped state of the vehicle based only on the speed information included in the GPS signal. Since the acceleration detected by the acceleration sensor 76 or the angular acceleration detected by the gyro sensor 78 is also related to the running / stopping state of the automobile, the running / stopping state of the automobile is determined based on the outputs of both sensors 76 and 78. Also good. For example, the example of FIG. 5 determines the running / stopped state based on the speed information included in the GPS signal and the acceleration detected by the acceleration sensor 76, and the example of FIG. 6 shows the acceleration detected by the acceleration sensor 76. Based on this, the running / stopped state is determined.

When GPS signal is received, at block 148, the system controller 40 determines whether the moving speed of the vehicle contained in the GPS signal is the first threshold V _H or more. If the speed is not the first threshold value V _H or runs block 146 again, the speed will wait until the above first threshold value V _H. During this time, the status parameter STATUS remains “stopped”.

If the speed is equal to or greater than the first threshold value V _H, at block 150, the system controller 40 determines whether the acceleration by the acceleration sensor 76 is detected is the first threshold value a _H or more. Since the acceleration can also represent the running / stopped state of the vehicle, in the example of FIG. 5, it is used for the state determination, but the state determination may be made based only on the speed information from the GPS signal. If the acceleration is not the first threshold value a _H or is performed block 146 again and waits until the acceleration becomes equal to or higher than the first threshold value a _H.

If the system controller 40 determines in block 150 that the acceleration is greater than or equal to the first threshold a _H , the system controller 40 sets “running” in the state parameter STATUS in block 152.

At block 154, the system controller 40 determines whether a GPS signal can be received. If it is determined that the GPS signal cannot be received, block 144 is executed again, and the system controller 40 sets “stop” in the status parameter STATUS. When the GPS signal is received, in block 156, the system controller 40 determines whether the moving speed of the vehicle included in the GPS signal is equal to or less than the second threshold value _VL . The second threshold value V _L is a speed equal to or lower than the first threshold value V _H. For example, the first threshold value V _H is 10 km / h, and the second threshold value V _L is 4 km / h. If the speed is not less than or equal to the second threshold value _VL , block 154 is executed again and waits until the speed is less than or equal to the second threshold value _VL . During this time, the status parameter STATUS remains “running”.

When speed falls below a second threshold value V _L, at block 158, the system controller 40, an acceleration by the acceleration sensor 76 detects and determines whether second threshold value or less a _L. The second threshold value _{a L} or less of the first acceleration threshold value _{a H.} If the acceleration is not less than the second threshold value a _L, is performed block 154 again and waits until the acceleration becomes equal to or lower than the second threshold value a _L.

The system controller 40 is a block 158, if it is determined that the acceleration is equal to or less than the second threshold value a _L, returns to block 144, the system controller 40 sets the "stop" state parameter STATUS.

  For both speed and acceleration, the first threshold value that changes from “stop” to “travel” is higher than the second threshold value that changes from “travel” to “stop”. If the speed does not exceed the first threshold value, the state does not change to “running”, but the state remains “running” even if the speed falls below the first threshold value. When the speed further decreases and falls below the second threshold, the state changes to “stop”. Thus, the state transition has a hysteresis characteristic. For example, when the speed frequently changes due to traffic jams or the like, if the state changes frequently, the overhead due to control switching becomes a problem, or the image file in the SD memory 62 becomes shredded. By providing the state transition with a hysteresis characteristic, these can be prevented.

  According to the process of FIG. 6, it is possible to determine the traveling state of the vehicle according to the speed information included in the GPS signal and the acceleration detected by the acceleration sensor 76.

In the example of FIG. 6, when the power is turned on in block 162, the system controller 40 initially sets “stop” in the status parameter STATUS in block 164. At block 166, the system controller 40 determines whether the acceleration by the acceleration sensor 76 is detected is the first threshold value a _H or more. If the acceleration is not the first threshold value a _H or is performed block 166 again and waits until the acceleration becomes equal to or higher than the first threshold value a _H.

If the system controller 40 determines in block 166 that the acceleration is greater than or equal to the first threshold a _H , the system controller 40 sets “running” in the status parameter STATUS in block 168. At block 170, the system controller 40 determines, at block 170, whether the acceleration is equal to or less than the second threshold value _{a L.} If the acceleration is not less than the second threshold value a _L, is performed block 170 again and waits until the acceleration becomes equal to or lower than the second threshold value a _L.

The system controller 40 is a block 170, if it is determined that the acceleration is equal to or less than the second threshold value a _L, at block 164, the system controller 40 sets the "stop" state parameter STATUS.

  6 can also determine the running state of the vehicle according to the acceleration detected by the acceleration sensor 76.

  The interrupt process will be described with reference to FIGS. The processing in FIG. 3 is based on the premise that the drive recorder is connected to the cigarette lighter socket 32 via a power cable and DC5V is supplied to the drive recorder. Although the engine cannot be turned off during operation, the power cable may get caught from the power connector 16 or the cigarette lighter socket 32 due to the hand being entangled with the power cable. The disconnection of the power cable can occur while traveling or stopping.

  When DC5V is not input, a voltage generated by discharging the capacitor 42 is supplied to various devices. Therefore, the SD card 62 is also configured to operate for some time (for example, 10 seconds), to close the file being accessed, and to terminate the OS. This amount of time is determined on the assumption that no files are uploaded or downloaded.

  Therefore, when the external power supply is turned off, the interrupt process of FIG. 7 is executed. In block 182, the system controller 40 always determines whether or not the power is off (DC5V is not input). When the system controller 40 detects power off, the system controller 40 sends a connection end command to the SD card 62 to disconnect the wireless LAN connection (WiFi connection) in block 184. In response to this command, the CPU 68 of the SD card 62 disconnects the WiFi module 66 and the smartphone 88. Therefore, even when the uploading / downloading by the smartphone 88 is stopped, the uploading / downloading is immediately terminated when the power is turned off.

  Thereafter, in block 186, the system controller 40 performs a closing process for the file being accessed by the SD card 62. When the disconnected power cable is reinserted and the power is turned on, the processing of FIG. 3, FIG. 5, or FIG. 6 is resumed.

  When the power is turned off in this manner, first, the wireless LAN connection (WiFi connection) is disconnected, so that the charge of the capacitor 42 can be used only for the termination process of the SD card 62, and the termination process is performed reliably. be able to. If the power is turned off without terminating the SD card 62, the file may be damaged.

  With reference to FIG. 8, the interrupt process when an accident occurs will be described.

  As shown in FIG. 3, since image data is written to the SD card 62 at regular intervals during traveling, images are recorded even if an accident occurs during traveling. However, during the stop, image data is written in the SDRAM 54 but not in the SD card 62. Even when the vehicle is stopped, it may collide with another vehicle, and it may be preferable to save the image. Also, if the GPS signal cannot be received as in a parking lot in a tunnel or building, the image data is not written to the SD card 62 as in the case of a stop, but an accident in the parking lot in the tunnel or building is not possible. It may be preferable to save the image.

  Therefore, as shown in FIG. 8, the system controller 40 always determines whether or not the detection value of the acceleration sensor 76 is a very large abnormal value. Since the acceleration becomes very large due to the collision, it is possible to detect the occurrence of an accident.

  If the acceleration indicates an abnormal value, the system controller 40 sends a connection end command to the SD card 62 to disconnect the wireless LAN connection (WiFi connection) in block 194. In response to this command, the CPU 68 of the SD card 62 disconnects the WiFi module 66 and the smartphone 88. In block 196, the system controller 40 reads all the image data recorded in the SDRAM 54 and writes it to the SD card 62.

The operation described above is shown in Table 1.

  As described above, according to the embodiment, the file can be uploaded and downloaded by the wireless LAN during the stop, and the writing of the image data to the SD card 62 is stopped during the upload / download. During traveling, at least uploading and downloading of files by the wireless LAN are stopped, and writing from the SDRAM 54 to the SD card 62 is periodically executed. Therefore, writing of image data from the SDRAM 54 to the SD card 62 and downloading of the image file read from the SD card 62 to the smartphone 88 by the wireless LAN or uploading from the smartphone 88 to the drive recorder are not performed at the same time. It is possible to prevent a possibility that the writing speed and reading speed of the SD card 62 are lowered and the writing of the image data to the SD card 62 is affected.

  Since running and stopping are determined based on the speed information included in the GPS signal and / or the output of the acceleration sensor, there is no need to connect to an in-vehicle network, SCC (serial communication controller), bus, etc. The state can be easily determined.

  When an accident is detected, the wireless LAN connection is cut to reduce power consumption, so that the drive time by the standby power source using the capacitor 42 can be extended.

  Note that the processing of the present embodiment can be realized by a computer program, so that the computer program can be installed and executed on a computer through a computer-readable storage medium storing the computer program, as in the present embodiment. The effect of can be easily realized.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment. For example, the present invention can be applied not only to a drive recorder but also to a taxi rear vision (a monitor viewed from the back seat), which incorporates a WiFi function and is accessed by a smartphone or the like, or a tablet terminal used in a car.

  40 ... system controller, 42 ... capacitor, 54 ... SDRAM, 56 ... camera, 62 ... SD card, 66 ... WiFi module, 72 ... GPS receiver, 76 ... acceleration sensor.

Claims (18)

An electronic device installed on a moving body,
A communication unit that is wirelessly connected to a communication device, transmits data to the communication device, or receives data from the communication device;
A nonvolatile semiconductor memory for storing data transmitted to the communication device;
A processing unit for writing data to the semiconductor memory, the processing unit stopping transmission of data to the communication device or reception of data from the communication device, depending on the movement status of the mobile body;
An electronic device comprising: It further comprises detection means for detecting the moving speed of the moving body,
When the moving speed is equal to or higher than the first speed, the processing unit stops data transmission to the communication device or reception of data from the communication device, and the moving speed is a second lower than the first speed. The electronic device according to claim 1, wherein when the speed is equal to or lower than the speed, data is transmitted to the communication device or data is received from the communication device. It further comprises detection means for detecting the moving speed of the moving body,
The processing unit stops wireless connection with the communication device when the moving speed is equal to or higher than the first speed, and wirelessly communicates with the communication device when the moving speed is equal to or lower than a second speed equal to or lower than the first speed. The electronic device according to claim 1, wherein connection is made. The electronic device further includes a standby power source,
The electronic device can be operated by an external power source or the standby power source,
The electronic device operates by the standby power source when the external power source is shut off,
The electronic device according to claim 1, wherein the processing unit stops wireless connection with the communication device when the external power supply is shut off. The moving body is an automobile;
A detector for detecting the acceleration of the automobile;
A camera for photographing the driving situation of the car;
A buffer memory for temporarily storing an output signal of the camera,
The electronic device according to claim 1, wherein when the acceleration of the moving body is equal to or higher than a first acceleration, the processing unit stops wireless connection with the communication device and writes a storage signal of the buffer memory to the semiconductor memory.   The electronic device according to claim 1, wherein the processing unit stops data writing to the semiconductor memory when receiving a data transmission request to the communication device or a data reception request from the communication device. A method for controlling an electronic device installed in a moving body,
Wirelessly connected to a communication device, transmitting data to the communication device, or receiving data from the communication device;
Storing data transmitted to the communication device in a non-volatile semiconductor memory;
Writing data to the semiconductor memory;
Depending on the movement status of the mobile body, stopping the transmission of data to the communication device or the reception of data from the communication device;
A control method comprising: Detecting the moving speed of the moving body;
When the moving speed is equal to or higher than the first speed, transmission of data to the communication device or reception of data from the communication device is stopped, and when the moving speed is equal to or lower than the second speed equal to or lower than the first speed, The control method according to claim 7, further comprising transmitting data to the communication device or receiving data from the communication device. Detecting the moving speed of the moving body;
When the moving speed is equal to or higher than the first speed, the wireless connection with the communication device is stopped, and when the moving speed is equal to or lower than the second speed equal to or lower than the first speed, the wireless connection with the communication device is performed. The control method according to claim 7, further comprising: The electronic device further includes a standby power source,
The electronic device can be operated by an external power source or the standby power source,
Operating the electronic device with the standby power supply when the external power supply is shut off;
The control method according to claim 7, further comprising: stopping wireless connection with the communication device when the external power supply is shut off. The moving body is an automobile;
Detecting the acceleration of the car;
Photographing the driving situation of the car with a camera;
Temporarily storing the output signal of the camera in a buffer memory;
The control method according to claim 7, further comprising: when the acceleration of the moving body is equal to or higher than a first acceleration, stopping wireless connection with the communication device and writing a storage signal of the buffer memory to the semiconductor memory. .   The control method according to claim 7, further comprising stopping data writing to the semiconductor memory when a data transmission request to the communication device or a data reception request from the communication device is received. A program for controlling an electronic device installed in a moving object,
Wirelessly connected to a communication device, transmitting data to the communication device, or receiving data from the communication device;
Storing data transmitted to the communication device in a non-volatile semiconductor memory;
Writing data to the semiconductor memory;
Depending on the movement status of the mobile body, stopping the transmission of data to the communication device or the reception of data from the communication device;
A program for running On the computer,
Detecting the moving speed of the moving body;
When the moving speed is equal to or higher than the first speed, transmission of data to the communication device or reception of data from the communication device is stopped, and when the moving speed is equal to or lower than the second speed equal to or lower than the first speed, The program according to claim 13, further causing transmission of data to the communication device or reception of data from the communication device. On the computer,
Detecting the moving speed of the moving body;
When the moving speed is equal to or higher than the first speed, the wireless connection with the communication device is stopped, and when the moving speed is equal to or lower than the second speed equal to or lower than the first speed, the wireless connection with the communication device is performed. 14. The program according to claim 13 for further executing. On the computer,
When the external power supply is shut off, operate the electronic device with a standby power supply,
The program according to claim 13, further causing the wireless connection with the communication device to be stopped when the external power supply is shut off. On the computer,
Detecting the acceleration of the automobile as the moving body;
Photographing the driving situation of the car with a camera;
Temporarily storing the output signal of the camera in a buffer memory;
14. The method according to claim 13, further comprising: stopping the wireless connection with the communication device when the acceleration of the moving body is equal to or higher than a first acceleration, and writing a storage signal of the buffer memory into the semiconductor memory. program. On the computer,
The program according to claim 13, further causing the data writing to the semiconductor memory to be stopped when a data transmission request to the communication device or a data reception request from the communication device is received.

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