JP2023106840A - On-vehicle device and program - Google Patents

Abstract

To provide an on-vehicle device and a program capable of preventing erroneous conversion of a date when converting GPS time into a date and time and accurately setting a date of a built-in clock of the on-vehicle device.SOLUTION: An on-vehicle device 1 includes a GPS communication module 3 and a main CPU 10. The main CPU 10 includes a memory 11 that stores cycle information 112 indicating the current cycle of accumulation of GPS weeks, determines whether or not a date output from the GPS communication module 3 is included in a date range corresponding to the cycle information 112 stored in the memory 11, corrects a date and time of a built-in clock 111 to a date and time output from the GPS communication module 3 in the case of affirmative determination, and re-sets first conversion information 321 stored in a memory 32 of the GPS communication module 3 based on the cycle information 112 stored in the memory 11 in the case of negative determination.SELECTED DRAWING: Figure 1

Description

The present invention relates to an onboard device and a program.

A drive recorder that corrects the time of the built-in clock of a CPU based on GPS time (GPS week number and GPS week second) obtained from a GPS (Global Positioning System) is known (see, for example, Patent Document 1).

Japanese Patent No. 5781795

The memory of the GPS communication module of the vehicle-mounted device stores conversion information for converting the GPS week number and GPS week seconds into date and time. is calculated. Here, since the accumulation of the GPS week number is performed once every 1024 weeks, the cycle information indicating the number of the accumulation of the GPS week number (3rd round as of 2021) is stored in the memory. included in the conversion information. If there is an error in this cycle information, the GPS communication module will calculate the date shifted by 1024 weeks, 2048 weeks, or 3072 weeks. In this case, the date of the built-in clock is erroneously corrected in the drive recorder described in Patent Document 1 above.

In view of the above circumstances, the present invention provides an on-vehicle device and a program that prevent erroneous date conversion when converting GPS time into date and time and can set the date of the on-board device's built-in clock accurately. intended to

The vehicle-mounted device of the present invention includes a conversion information storage unit that stores conversion information for converting GPS time, including the GPS week number and GPS week seconds received by the GPS antenna, into date and time; A conversion unit that converts the GPS time into the date and time based on the conversion information stored in the conversion information storage unit and outputs the date and time, and indicates the current cycle of the accumulation of the GPS week number. whether or not the cycle information storage unit storing the cycle information and the date output from the conversion unit are included in the range of dates corresponding to the cycle information stored in the cycle information storage unit; a determination unit that determines the internal clock, and if the determination unit determines that the date output from the conversion unit is included in the range of dates corresponding to the cycle information, A correction unit that corrects the date and time to the date and time output from the conversion unit; a conversion information setting unit for resetting the conversion information stored in the conversion information storage unit based on the cycle information stored in the cycle information storage unit when it is determined that the conversion information is not available. .

The program of the present invention comprises a conversion information storage unit storing conversion information for converting GPS time, including the GPS week number and GPS week seconds received by the GPS antenna, into date and time; a conversion unit for converting GPS time into the date and time based on the conversion information stored in the conversion information storage unit and outputting the date and time; an internal clock; A program for controlling a vehicle-mounted device comprising a cycle information storage unit storing cycle information indicating whether the date output from the conversion unit is stored in the cycle information storage unit a determination process for determining whether or not the date output from the conversion unit is included in the date range corresponding to the cycle information by the determination process; correction processing for correcting the date and time of the built-in clock to the date and time output from the conversion unit when it is determined that the date output from the conversion unit is correct by the determination processing; when it is determined that the dates are not included in the range of dates corresponding to the cycle information, the conversion information stored in the conversion information storage unit is changed to the cycle information stored in the cycle information storage unit. The vehicle-mounted device is caused to execute a conversion information setting process for resetting based on the conversion information.

According to the present invention, even if the conversion information for converting the GPS time into the date and time on the GPS communication module side is not correct, it is possible to prevent incorrect conversion of the date when converting the GPS time into the date and time. can be used to accurately set the date of the onboard device's built-in clock.

FIG. 1 is a block diagram showing functions of a vehicle-mounted device according to one embodiment of the present invention. FIG. 2 is a flow chart showing correction processing of the time of the built-in clock in the vehicle-mounted device shown in FIG.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below along with preferred embodiments. It should be noted that the present invention is not limited to the embodiments described below, and can be modified as appropriate without departing from the gist of the present invention. In addition, in the embodiments shown below, there are places where illustrations and explanations of some configurations are omitted, but the details of the omitted technologies are provided within the scope that does not cause contradiction with the contents explained below. , Appropriately known or well-known techniques are applied.

FIG. 1 is a block diagram showing functions of a vehicle-mounted device 1 according to one embodiment of the present invention. The vehicle-mounted device 1 shown in this figure is a drive recorder, and particularly in this embodiment, it is a drive recorder mounted on a forklift.

The vehicle-mounted device 1 includes a GPS antenna 2 , a GPS communication module 3 , and a main CPU (Central Processing Unit) 10 . The GPS antenna 2 receives GPS signals transmitted from GPS satellites. This GPS signal contains GPS time. This GPS time includes the GPS week number (week number) and GPS seconds within the week. The GPS second-in-week is the exact time ticked by the GPS atomic clock, incrementing by 1 from 0 at the beginning of each GPS week to 67499 at the end of each GPS week, and back to 0 when the GPS week changes.

The GPS week number is 10-bit information. Since the GPS week number is 10-bit information, it takes 2 ¹⁰ =1024 weeks. That is, the GPS week number increases by 1 from 0 to 1023, and then returns to 0 again. The first round of GPS weeks is from January 6, 1980 (Japan time) to August 22, 1999 (Japan time). The second round of GPS weeks is from August 22, 1999 (Japan time) to April 7, 2019 (Japan time). Furthermore, the third round of GPS weeks is from April 7, 2019 (Japan time) to November 21, 2038 (Japan time).

The number of accumulated weeks from the time when it started synchronizing with UTC (Coordinated Universal Time) is 0 to 1023 in the first round of GPS weeks, 1024 to 2047 in the second round of GPS weeks, and It is 2048-3071 in the third round of the number of weeks. 2021 is included in the third round of GPS weeks.

The GPS communication module 3 has a GPS time conversion function 31 and a memory 32 . The memory 32 stores a program for executing the GPS time conversion function 31, and first and second conversion information 321 and 322 for converting the GPS week number and GPS week seconds into date and time. there is The first conversion information 321 is information for converting the GPS week number (0 to 1023) into the accumulated number of weeks (2048 to 3071) from the UTC start date (January 6, 1980) to the present. The second conversion information 322 is information for converting the cumulative number of weeks and the GPS seconds within a week (0 to 67499) into a date and time.

The GPS time conversion function 31 converts the GPS week number (0 to 1023) received by the GPS antenna 2 into the current cumulative week number (2048 to 3071) based on the first conversion information 321 stored in the memory 32. . In addition, the GPS time conversion function 31 converts the current cumulative week number converted from the GPS week number and the GPS week seconds (0 to 67499) received by the GPS antenna 2 into the second conversion information 322 stored in the memory 32. Based on this, the current date (April 7, 2019 to November 21, 2038) and time (00:00:00 to 23:59:59) are converted and output to the main CPU 10.

Here, the first conversion information 321 is information indicating to which round the current accumulated week number (2048 to 3071) corresponds to the accumulated GPS week number. That is, the memory 32 stores the information “3rd round” as the first conversion information 321 .

The second conversion information 322 is information such as mathematical formulas and tables indicating the relationship between the accumulated number of weeks and seconds in the GPS week, and the date and time. The GPS time conversion function 31 converts the current integrated week number and GPS week seconds into the current date and time based on the formula, table, or the like.

The main CPU 10 includes a memory 11 , a time correctness determination function 12 , a time correction function 13 , a conversion information setting function 14 , a communication function 15 and a cycle information setting function 16 . The memory 11 stores a program for executing each function of the main CPU 10 , the time of an internal clock 111 (RTC (Real Time Clock) time), and cycle information 112 . The cycle information 112, like the first conversion information 321, is information indicating which cycle the accumulation of the GPS week number corresponds to. As of December 2021, the round information 112 corresponds to the third round. That is, in the memory 11, the information "3rd round" is stored as the round information 112. FIG.

The time correctness determination function 12 calculates the date range (April 7, 2019 to November 21, 2038) corresponding to the cycle information 112 stored in the memory 11 . Then, the time correctness determination function 12 determines that the current date output from the GPS time conversion function 31 of the GPS communication module 3 corresponds to the date range (April 7, 2019 to November 2038) corresponding to the cycle information 112. 21st), and outputs the determination result to the time correction function 13 and the conversion information setting function 14 .

The time correction function 13 is stored in the memory 11 when a determination result (positive determination) that the date output from the GPS time conversion function 31 is included in the date range corresponding to the cycle information 112 is input. The date and time of the built-in clock 111 are corrected to the date and time output from the GPS time conversion function 31 .

On the other hand, the conversion information setting function 14 receives a determination result (negative determination) that the date output from the GPS time conversion function 31 is not included in the range of dates corresponding to the cycle information 112. The first conversion information 321 stored in the memory 32 of the communication module 3 is reset by the cycle information 112 stored in the memory 11 .

The communication function 15 communicates with an external terminal 4 such as a mobile terminal or a PC (Personal Computer) using wireless communication technology such as Bluetooth (registered trademark). The external terminal 4 has a communication function 41 and a memory 42 . The communication function 41 communicates with the vehicle-mounted device 1 and other devices by wireless communication technology such as Bluetooth.

The memory 42 stores cycle information 112 . The external terminal 4 outputs the cycle information 112 stored in the memory 42 to the vehicle-mounted device 1 according to the user's operation. The cycle information 112 output from the external terminal 4 is input to the cycle information setting function 16 via the communication function 15 . When the cycle information 112 is input, the cycle information setting function 16 resets the cycle information 112 stored in the memory 11 based on the input cycle information 112 .

FIG. 2 is a flow chart showing a process of correcting the time of the built-in clock 111 in the vehicle-mounted device 1 shown in FIG. The correction process shown in this flowchart is started when the vehicle-mounted device 1 is activated, and proceeds to step S1. The vehicle-mounted device 1 is automatically activated when the ignition of a vehicle such as a forklift is turned on.

In steps S1 to S3, the main CPU 10 of the vehicle-mounted device 1 executes a normal processing loop. The condition for exiting this normal processing loop is that the ignition of the vehicle is turned off, and the main CPU 10 continues the reception processing of the GPS antenna 2 until the ignition of the vehicle is turned off (step S2).

In step S4 after exiting the normal processing loop, the time correctness determination function 12 of the main CPU 10 determines the date range (April 7, 2019 to November 2038) corresponding to the cycle information 112 stored in the memory 11. 21 days) is calculated. Next, in step S5, the time correctness determination function 12 determines that the date output from the GPS time conversion function 31 of the GPS communication module 3 corresponds to the date range (April 7, 2019 to 2038) corresponding to the cycle information 112. November 21, 2012), and outputs the determination result to the time correction function 13 and the conversion information setting function 14 . If an affirmative determination is made in step S5, the process proceeds to step S6, and if a negative determination is made in step S5, the process proceeds to step S7.

In step S<b>6 , the time correction function 13 of the main CPU 10 corrects the date and time of the built-in clock 111 stored in the memory 11 to the date and time output from the GPS time conversion function 31 . Thus, the process of correcting the time of the built-in clock 111 is finished, and the vehicle-mounted device 1 stops.

On the other hand, in step S7, the conversion information setting function 14 of the main CPU 10 resets the first conversion information 321 stored in the memory 32 of the GPS communication module 3 with the cycle information 112 stored in the memory 11. . Thus, the process of correcting the time of the built-in clock 111 is finished, and the vehicle-mounted device 1 stops.

That is, in the vehicle-mounted device 1 of the present embodiment, the correction processing of the time of the built-in clock 111 is executed once after the ignition of the vehicle is turned on until it is turned off. In the process of correcting the time of the built-in clock 111, the main CPU 10 determines whether the conversion from the GPS week number and the seconds within the GPS week to the date executed by the GPS communication module 3 is correct. Specifically, the time correctness determination function 12 of the main CPU 10 determines whether the date output from the GPS communication module 3 is correct or incorrect within the date range corresponding to the correct cycle (currently the third cycle). It is determined by whether or not Then, if the conversion is correct, the conversion information setting function 14 of the main CPU 10 corrects the date of the built-in clock 111 according to the converted date. On the other hand, if the conversion is erroneous, the conversion information setting function 14 resets the first conversion information 321 relating to the cycle stored in the memory 32 of the GPS communication module 3 with the cycle information 112 stored on the main CPU 10 side. . As a result, even if the first conversion information 321 is incorrect on the GPS communication module 3 side, the GPS week number and the GPS week seconds received by the GPS antenna 2 are converted into accurate dates, and the built-in clock of the vehicle-mounted device 1 is corrected. 111 dates can be set accurately.

Further, in the vehicle-mounted device 1 of the present embodiment, when the first conversion information 321 as the cycle information is incorrect, the first conversion information 321 is reset by the cycle information 112 stored on the main CPU 10 side. . As a result, the GPS time conversion function 31 of the GPS communication module 3 can be prevented from calculating the accumulated number of weeks shifted by 1024 weeks, 2048 weeks, or 3072 weeks. Therefore, the date can be calculated based on the accurate accumulated number of weeks by the GPS time conversion function 31, and the date of the built-in clock 111 of the vehicle-mounted device 1 can be corrected accurately.

In addition, in the vehicle-mounted device 1 of the present embodiment, the cycle information 112 stored in the memory 42 of the external terminal 4 is input to the main CPU 10, and the cycle information 112 stored in the memory 11 is input based on the input cycle information 112. can be reset. As a result, even if the cycle information 112 stored in the memory 11 of the main CPU 10 is out of order or lost, the correction processing of the time of the built-in clock 111 of this embodiment can be continued.

Although the present invention has been described above based on the embodiments, the present invention is not limited to the above-described embodiments, and may be modified without departing from the scope of the present invention. You can combine techniques. For example, in the above embodiment, the vehicle-mounted device 1 is a drive recorder, but the present invention can also be applied to other vehicle-mounted devices such as a digital tachograph, a car navigation system, and a driving support system.

Moreover, although the vehicle-mounted device 1 of the above embodiment has the GPS antenna 2 built therein, the GPS antenna 2 may be provided separately from the vehicle-mounted device 1 and may be connected by wire or wirelessly. Alternatively, instead of inputting the round information 112 to the main CPU 10 through wireless communication with the external terminal 4, a recording medium on which the round information 112 is recorded may be connected to the main CPU 10 to transmit the round information 112 to the main CPU 10. You may make it input.

Furthermore, in the vehicle-mounted device 1 of the above-described embodiment, the time correction process of the built-in clock 111 is performed after the ignition of the vehicle is turned off. processing may be performed.

1: On-vehicle device 2: GPS antenna 11: Memory (cycle information storage unit)
12: Time correctness judgment function (judgment unit)
13: Time correction function (correction unit)
14: Conversion information setting function (conversion information setting part)
15: Communication function (input unit)
16: Cycle information setting function (cycle information setting unit)
31: GPS time conversion function (conversion unit)
32: memory (conversion information storage unit)
42: Memory (external recording medium)
111: built-in clock 112: cycle information 321: first conversion information (conversion information, cycle information)
322: Second conversion information (conversion information, relationship information)

Claims (4)

a conversion information storage unit storing conversion information for converting the GPS time received by the GPS antenna, including the GPS week number and the GPS time within the GPS week, into a date and time;
a conversion unit that converts the GPS time received by the GPS antenna into the date and time based on the conversion information stored in the conversion information storage unit and outputs the date and time;
a cycle information storage unit storing cycle information indicating the current cycle of the accumulation of the GPS week number;
a determination unit that determines whether the date output from the conversion unit is included in a range of dates corresponding to the cycle information stored in the cycle information storage unit;
built-in clock and
When the determination unit determines that the date output from the conversion unit is included in the date range corresponding to the cycle information, the date and time of the built-in clock are output from the conversion unit. a correction unit for correcting the date and time;
When the determination unit determines that the date output from the conversion unit is not included in the range of dates corresponding to the cycle information, the conversion information stored in the conversion information storage unit is and a conversion information setting unit configured to reset based on the cycle information stored in the cycle information storage unit. The conversion information includes the cycle information and relationship information indicating the relationship between the accumulated number of weeks and the GPS seconds in the week corresponding to the cycle information and the date and time,
The conversion unit converts the GPS week number received by the GPS antenna into the accumulated week number corresponding to the cycle information stored in the conversion information storage unit, and the accumulated week number and the GPS antenna receive converting the GPS second within a week to the date and time based on the relational information stored in the conversion information storage unit and outputting the date and time;
When the determination unit determines that the date output from the conversion unit is not included in the range of dates corresponding to the cycle information, the conversion information setting unit stores 2. The vehicle-mounted device according to claim 1, wherein the cycle information stored in the conversion information storage unit is reset based on the stored cycle information. an input unit for inputting the cycle information stored in an external recording medium;
3. The vehicle-mounted device according to claim 1, further comprising a cycle information setting unit that resets the cycle information stored in the cycle information storage unit according to the cycle information input by the input unit. a conversion information storage unit storing conversion information for converting the GPS time received by the GPS antenna, including the GPS week number and the GPS time within the GPS week, into a date and time;
a conversion unit that converts the GPS time received by the GPS antenna into the date and time based on the conversion information stored in the conversion information storage unit and outputs the date and time;
built-in clock and
A program for controlling a vehicle-mounted device comprising a cycle information storage unit storing cycle information indicating the current cycle of the GPS week number integration,
a determination process for determining whether or not the date output from the conversion unit is included in a range of dates corresponding to the cycle information stored in the cycle information storage unit;
When it is determined by the determination process that the date output from the conversion unit is included in the range of dates corresponding to the cycle information, the date and time of the built-in clock are output from the conversion unit. a correction process for correcting the date and time;
When it is determined by the determination process that the date output from the conversion unit is not included in the range of dates corresponding to the cycle information, the conversion information stored in the conversion information storage unit is A program for causing the vehicle-mounted device to execute conversion information setting processing for resetting based on the cycle information stored in the cycle information storage unit.

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