JPH04369095A - Method for storing numerical data for electronic integrator - Google Patents

Abstract

PURPOSE:To suppress the writing of data in a defective position and to improve reliability by dividing a storage area in a non-volatile memory into a data area and a counter area, and in a specific condition, newly storing data in a unused area. CONSTITUTION:In a method for rewriting numerical data stored in the non- volatile memory to new numerical data and storing the new data, the storage area of the non-volatile memory is divided into a data area A for storing numerical data and a counter area B for storing the rewritten frequency of numerical data in the data area A. The area A is divided into a distance value area C for storing an integrated traveling distance value and a pulse number area D for storing the integrated number of pulses and the counter area B is divided into an area E for storing rewriting frequency in the area D and an area F for storing rewriting frequency in the area C. When the value of the area A reaches rewriting guarantee frequency or no data can be stored in the areas A, B, the numerical data are stored in an used storage area.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a numerical data storage method for an electronic totalizer that stores information such as cumulative mileage of a vehicle and cumulative operating time of a marine engine in a non-volatile memory.

0002

2. Description of the Related Art Conventionally, there is an electronic odometer that employs a method of storing the cumulative mileage of a vehicle in a non-volatile memory, as disclosed in, for example, Japanese Patent Laid-Open No. 2-8713. In this electronic odometer, the storage area of the nonvolatile memory is divided into three areas, and each storage area stores numerical data for the upper digit, middle digit, and lower digit of the cumulative mileage number. Since there is a limit to the number of times numerical data can be rewritten in non-volatile memory,
In conventional electronic odometers, the three storage areas are replaced periodically. That is, the storage area for lower digits, which has been rewritten relatively frequently, is replaced with the storage area for upper digits, which has been rewritten relatively few times.

0003

[Problems to be Solved by the Invention] However, although conventional electronic odometers are configured to replace the storage area in non-volatile memory, the number of rewrites in non-volatile memory exceeds the guaranteed number of times. Since it is not possible to detect whether or not the target has been reached, reliability is low. Furthermore, if there is a defect in even one part of the area to be stored, there is also the problem that numerical values cannot be stored accurately.

0004

[Means for Solving the Problems] The method for storing numerical data in an electronic totalizer according to the present invention includes a data area for storing numerical data, and a counter area for storing the number of times the numerical data has been rewritten in this data area. Numerical data and the number of times the numerical data has been rewritten are each stored in a non-volatile memory that has storage areas divided into two. When the data cannot be confirmed after being read once, the numerical data and the number of times the numerical data has been rewritten are newly stored in unused portions of the storage area.

[0005]

[Operation] Numerical data is rewritten in the data area until the guaranteed number of rewrites is reached, and data is stored in the data area and counter area while avoiding defective areas.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 8. Fig. 1 is a side view of a motorcycle equipped with an electronic odometer employing the numerical data storage method according to the present invention, and Fig. 2 is a side view of an electronic odometer used to implement the numerical data storage method of the present invention. A block diagram showing the configuration, FIG. 3 is a circuit diagram of a self-power-off circuit similarly used in an electronic odometer, and FIG. 4 is a diagram showing an address map of a nonvolatile memory used in carrying out the numerical data storage method of the present invention. , FIG. 5 is an enlarged view of the data area of the address map shown in FIG. 4, FIG. 6 is an enlarged view of the counter area of the address map shown in FIG. 4, and FIG. 7 is an enlarged view of the data area of the address map shown in FIG. A flowchart showing a method for storing numerical data of an odometer. FIG. 8 is a flowchart showing an operation when storing odometer data in a nonvolatile memory. In these figures, 1 is an off-road motorcycle, 2 is a frame of this motorcycle 1, 3 is an engine, 4 is a front wheel steerably connected to the frame 2 via a front fork 5, and 6 is a rear arm. The rear wheel is swingably supported by the frame 2 via 7. 8 is a handle, 9 is a fuel tank, and 10 is a seat. In addition,
11 is a cowling structured to cover the front part of the vehicle body.

12 is an electronic odometer according to the present invention,
The odometer 12 includes a display section 13 that is a digital display installed in front of the steering wheel 8, and a control unit 15 that is installed below the seat 10 and connected to the display section 13 via a connection cord 14. It is composed of. The display section 12 includes a liquid crystal display unit 13a, and is supported by the cowling 11 via mounting hardware (not shown). Display unit 1
3a, in this example, the speed is expressed as 3 digits in decimal notation,
The system is designed to display the cumulative mileage in decimal notation using only 6 digits. In addition, the minimum digit of the cumulative mileage number is 0.
．． It is displayed as 1km. Further, the liquid crystal display unit 13a is equipped with a surface emitting element that illuminates the liquid crystal plate from the back side. This surface emitting element is shown as E in Figure 2.
Indicated by L. The control unit 15 is connected via a power cord 17 to a battery 16 located below the seat, and is also connected via a sensor cord 19 to a speed sensor 18 that detects the rotational speed of the output shaft of the engine 3. There is. Note that this speed sensor 18 outputs a pulse signal of 1 when the motorcycle 1 travels 0.4 m.
A device that outputs pulses to the control unit 15 is adopted.

Next, the configuration of the control unit 15 will be explained with reference to FIGS. 2 and 3. As shown in FIGS. 2 and 3, the control unit 15 includes a CPU 2
0 and volatile memory (hereinafter referred to as RAM) 2
1, a self-power-off circuit 23 as a power-off means interposed between the control unit 22 and the battery 16, and numerical data (mileage data). , the cumulative number of pulses), etc. This non-volatile memory 24 is an EEPROM.
is used. Note that 25 is a main switch of the motorcycle 1, and 26 is a power supply circuit connected to the self-power-off circuit 23 to supply stabilized power to the control unit 22.

Reference numeral 27 indicates an oscillation element constituting an oscillation circuit for driving the CPU 20, 28 indicates a CPU set consisting of a watchdog timer that resets the CPU 20 when the CPU 20 goes out of control, and 29 and 30 drive the display unit 13a. An oscillation circuit 29a is connected to the liquid crystal driver 29, which is a liquid crystal driver and a booster circuit for displaying numerical data. 31 is CP
This is a jumper wire for changing the operating conditions of U20, and the CPU 20 used in this embodiment can change the meter specifications depending on the model of the motorcycle by changing the connection point of this jumper wire 31. It is configured. With such a structure, the specifications of the meter (oddometer) can be easily changed. Said CP
When the main switch 25 is turned on (input state), the U20 calculates the speed and cumulative mileage of the motorcycle 1 from the number of pulses of the pulse signal emitted from the speed sensor 18, and calculates the cumulative number of pulses and the cumulative mileage. RA the number
It is configured to store the speed and cumulative mileage number in the M21, and to digitally display the speed and cumulative mileage number on the display unit 13. Note that the CPU 20 used in this example has a 100 m
The vehicle is configured to store the cumulative distance traveled in the nonvolatile memory 24 each time the vehicle travels. Furthermore, when a switch-off detection signal is input from the self-power-off circuit 23, which will be described later, the cumulative number of pulses and the cumulative mileage number stored in the RAM 21 are stored in the non-volatile memory 24, and the self-power-off circuit 23 When a switch-on detection signal is input from the non-volatile memory 24, the above-mentioned data stored in the non-volatile memory 24 are written into the RAM 21, and then the above-mentioned input state is established. and,
Since there is a limit to the number of times that numerical data can be rewritten in the non-volatile memory 24 such as an EEPROM used in this embodiment, the CPU 20 uses the numerical data (total distance traveled, cumulative pulse number) in the non-volatile memory 24. ) is configured to store the numerical data in an unused storage area of the nonvolatile memory 24 when the number of rewrites reaches the guaranteed number of rewrites. In this embodiment, an EEPROM with a guaranteed number of rewrites of approximately 100,000 times is used. Further, the value of the number of rewrites (hereinafter, this numerical value will be referred to as counter data) is stored separately from the numerical data in a storage area of the nonvolatile memory 24, which will be described later. In addition, when there is a location in the storage area of the non-volatile memory 24 where data cannot be stored, data is stored in such a way as to avoid that location. A method for checking the location where data cannot be stored is to store data in the non-volatile memory 24 and then read the data once, and then compare the data in the RAM 21 and the data in the non-volatile memory 24 when the data could not be read. When the data do not match, a method is adopted in which it is determined that the storage portion of the data is an unstorable portion. In this case, the data includes, in addition to the above-mentioned cumulative travel distance and cumulative pulse number, counter data indicating the number of times of rewriting in the nonvolatile memory 24.

The self-power-off circuit 23 is connected to the battery 16 via a main power line connected to the main switch 25 from a connection point a, and a backup line bypassing the main switch 25 from a connection point b.
The structure is such that power is supplied even if the main switch 25 is turned off. And this self power off circuit 23
is configured to output a switch-off detection signal to the CPU 20 when the main switch 25 is turned off, and cut off power supply to the CPU 20, nonvolatile memory 24, etc. when a data storage end signal from the CPU 20 is input. . Further, when the main switch 25 is turned on, a switch-on detection signal is output to the CPU 20. Note that in FIGS. 2 and 3, symbol c indicates a connection point to which a switch-off detection signal and switch-on detection signal are input/output, and d indicates a connection point to which a data storage end signal from the CPU 20 is input. Note that e and f indicate the input side connection point and the output side connection point of the power supply circuit 26.

The nonvolatile memory 24 uses a large number of 8-bit (1 byte) memory blocks arranged as shown in FIGS. 4 to 6. In FIGS. 4 to 6, one square indicates a storage area for one bit, and the storage block is composed of eight squares arranged in a horizontal row in the figures. The storage area of this non-volatile memory 24 is a data area A that stores the cumulative mileage number and the cumulative pulse number.
and a counter area B that stores the number of times the data area A has been rewritten. Further, the data area A is divided into a distance number area C that stores the cumulative number of traveled distances, and a pulse number area D that stores the cumulative number of pulses. In the distance number area C, 6 displayed on the display unit 13
The cumulative mileage number for the digits is allocated and stored in memory blocks two digits at a time. That is, when storing the cumulative mileage number for the first time, the lower two digits are stored in the lowest two digits in the lowest memory block in FIGS. 4 and 5 among the many memory blocks in the distance number area C. The middle two digits are stored in a storage block, and the upper two digits are stored in an adjacent storage block. In addition, in order to store the cumulative mileage number, the cumulative pulse number described later, counter data, etc. in the nonvolatile memory 24, the decimal data is converted into binary numbers, and this binary data is stored in each storage block. I will do it. In FIGS. 4 to 6, upper and lower digit data storage blocks, middle digit data storage blocks, and lower digit data storage blocks that store mileage data of upper digits, middle digits, and lower digits are respectively shown. Marked as middle and bottom.

In the pulse number area D, the cumulative number of pulses stored in the RAM 21 in the control unit 15 is stored. When storing the cumulative pulse number, all digits are stored at once, instead of being stored digit by digit like the mileage number.

The counter area B is a pulse counter data area E that stores the number of rewrites in the pulse number area D.
and a distance counter data area F that stores the number of rewrites in the distance number area C. Further, the distance counter data area F is a lower digit area G as shown in FIG.
, middle digit area H, and upper digit area I. Of these three areas, the lower digit area G stores the number of rewrites in the memory block that stores the lower two digits of the cumulative mileage number in the distance number area C. In other words, in the lower digit area G, FIGS.
The number of rewrites in the lowest memory block is stored. Similarly, the middle digit area H stores the number of rewrites in the memory block that stores the middle two digits of the cumulative mileage number, and the high-order digit area I stores the top two digits of the cumulative mileage number. The number of rewrites in each memory block is stored. In the pulse counter data area E, the number of rewrites in the pulse number area D is stored.

Next, the operation of the electronic odometer according to the present invention will be explained with reference to FIGS. 7 and 8. First, when the main switch 25 is turned on, C is set as the initial setting in S1.
Setup of the PU 20 is performed. Next, in S2, the numerical data (accumulated pulse number, accumulated distance traveled) stored in the nonvolatile memory 24 is read out and written into the RAM 21. Then, the motorcycle 1 is driven in this state. While the vehicle is running, the CPU 20 counts pulses emitted from the speed sensor 18 in S3, and calculates the distance traveled from the counted values. At this time, the cumulative number of pulses is stored in the RAM 21. In this embodiment, the pulse is emitted once when the vehicle travels 0.4 m. The travel distance data is sent to the liquid crystal driver 29 in S5 after passing through a distance data addition step S4, which will be described later, and is displayed on the display unit 13a in S6. Further, in S6, the speed calculated by the CPU 20 from the number of pulses is also displayed on the display unit 13a at the same time. Next, in the determination step S7, it is checked whether the main switch 25 is turned off, and the main switch 25 is turned off.
If 5 is not cut off, the process returns to S3. That is,
After the main switch is turned on, the distance data addition and display steps are repeated until the main switch 25 is turned off.

The distance data addition step S4 will now be described in detail with reference to FIG. Distance data addition step S4
In this case, the cumulative mileage number is updated every time the motorcycle 1 travels 100 m and is stored in the nonvolatile memory 24 each time. P1 in FIG. 8 is a step for determining whether the vehicle has traveled 100 m, and when the lowest numerical value of the displayed distance number displayed on the display unit 13 increases by 1 (indicating 100 m), the process advances to the next step P2. At P2, mileage data for the lower two digits of the displayed distance number is stored in the lower digit data storage block of the distance number area C of the nonvolatile memory 24. At this time, data is stored in the lowest storage block in FIGS. 4 and 5. Next, P3 indicates that the memory block for lower digit data of the non-volatile memory 24 has been rewritten once.
In step P4, it is determined whether the mileage data is stored in the storage block for lower digit data. The method of determination is to read the data in the storage block for lower digit data once and check whether the data exists or not, and if it is data, check whether it matches the data in the RAM 21. .

When it is determined at P4 that the mileage data is not stored, it is determined that the storage block cannot be stored, and at P5 the storage blocks for upper, middle, and lower digit data are shifted one byte at a time. In other words, Figure 5
If there is a defective location indicated by C1 in the storage block for lower digit data in , the 1-byte memory block containing the defective location is not used, and the memory block indicated by (1) is placed on the left side of the address map in Figure 5. , the next storage block next to each storage block that has been used up to that point will be used from next time. After shifting the memory blocks in this manner, the counter data of the memory blocks used for the upper, middle, and lower digits is changed at P6. The counter data of the lower digit data storage block is stored in the lower digit area G of the distance counter data area F, the counter data of the middle digit data storage block is stored in the middle digit area H, and the counter data of the upper digit data storage block is stored in the lower digit area G of the distance counter data area F. Since they are stored in the upper digit area I, in the above case, the lower digit area G
storage block for middle digit data (2nd from the bottom in Figure 5)
Writes the counter data in the memory block (the first memory block). Furthermore, the counter data in the storage block for upper digit data is stored in the middle digit area H, and the counter data in the storage block next to the upper digit data storage block is stored in the upper digit area I (
In this case, since it is an unused portion, 0 is stored. )
Write each. In addition, in this embodiment, since the non-volatile memory 24 with a guaranteed number of rewrites of 100,000 times is used, the counter area B is divided into 3 bytes each so that the counter data value can be stored up to 100,000 in binary. Counter data is stored in the designated storage area. This 3-byte storage area is shown in parentheses on the right side of FIG. Note that if there is no defective location in the distance number area C, each memory block is rewritten once when the lower digit data memory block reaches a predetermined number of rewrites, as shown on the right side of the address map in FIG. Shift bytes.

After changing the counter data at P6, the process returns to P2 and the lower digit storage operation is performed again.

[0018] When the data can be confirmed in P4 above (
When the mileage data for the lower two digits is stored in the non-volatile memory 24), it is determined at P7 whether the mileage data for the lower digits has overflowed.
8, 1 is added to the middle digit of the mileage data stored in the RAM 21. If there is no overflow, the process returns to the input waiting state.

Next, at P9, the mileage data for the middle two digits of the displayed distance number is stored in the middle digit data storage block of the distance number area C of the nonvolatile memory 24. Note that if the storage block has not been shifted in the lower digit storage step described above (writing is OK in the determination step P4)
), the data is stored in the storage block located in the second row from the bottom in FIG. 5, and if the storage block is shifted by 1 byte as shown in (1) in FIG. Data is stored in the storage block located in the third row from the bottom. Next, in P10, RA
M21, and in P11 it is determined whether the mileage data is stored in the middle digit data storage block.
Confirm using the same method as in 4. When the check result in P11 is NO, it is determined that the storage block cannot be stored, and the storage blocks for upper, middle, and lower digit data are shifted by 2 bytes at P12. In other words, Figure 5
If there is a defective location shown as C2 in the storage block for middle-order digit data in , the 1-byte storage block containing the defective location is not used, and the address map shown in (2) is placed on the left side of the address map in Figure 5. As shown, the memory blocks above the defective location will be used from next time onwards. After shifting the memory blocks in this way, the counter data of the memory blocks used for the upper, middle, and lower digits is set to P13.
Changes will be made in In this case, the counter data in the storage block for upper digit data (the fourth storage block from the bottom in FIG. 5) is written in the lower digit area G. Furthermore, the counter data in the storage block next to the above storage block for upper digit data is stored in the middle digit area H (in this case, 0 is stored because it is an unused portion), and the counter data is further stored in the upper digit area I. Furthermore, the counter data in the adjacent memory block (also in this case, 0 is stored since it is an unused portion) is written respectively. After changing the counter data in P13, the process returns to P9 and the middle digit storage operation is performed again.

When the confirmation result at P11 is OK (when the mileage data for the middle two digits is stored in the non-volatile memory 24), it is checked at P14 whether the mileage data for the middle digits has overflowed. When you judge whether or not, and the digits overflow,
At P15, 1 is added to the upper digit of the mileage data stored in the RAM 21. If there is no overflow, the process returns to the input waiting state.

Next, in P16, the mileage data for the upper two digits of the displayed distance number is stored in the upper digit data storage block of the distance number area C of the nonvolatile memory 24. Note that if the memory block is not shifted in the middle digit storage step described above (if writing is OK in the determination steps P4 and P11), the memory block located in the third row from the bottom in FIG. When data is stored in a block and the storage block is shifted by one byte as shown in (1) in FIG. 5, the data is stored in the storage block located at the fourth stage from the bottom. Similarly, Figure 5
If the data has been shifted as shown in (2), the data is stored in the sixth storage block from the bottom. Next, the fact that the storage block for upper digit data of the non-volatile memory 24 has been rewritten once is stored in the RAM 21 in P17, and P1
At step 8, it is confirmed whether or not the mileage data has been stored in the upper digit data storage block using the same method as at step P4.

When the check result at P18 is NO, it is determined that the storage block cannot be stored, and the storage blocks for upper, middle, and lower digit data are shifted by 3 bytes at P19. In other words, if there is a defective location indicated by C3 in the storage block for high-order digit data in FIG. As shown in (3), the memory blocks above the defective location will be used from next time onwards. After shifting the memory blocks in this manner, the counter data of the memory blocks used for the upper, middle, and lower digits is changed in P20. In this case, all data storage blocks for upper digits, middle digits, and lower digits are changed to unused areas, so lower digit area G, middle digit area H, and upper digit area I of counter area B are Write 0 to each. After changing the counter data in P20, the process returns to P16 and the upper digit storage operation is performed again.

When the confirmation result at P18 is OK (when the mileage data for the upper two digits is stored in the non-volatile memory 24), at P21 the counter data in the storage block for lower digit data is the guaranteed number of times. Determine whether it exists or not. The determination method at this time is to check whether the numerical value written in the lower digit area G of the counter area B is 100,000 or less. If the guaranteed number of times has not been reached, the process returns to the input waiting state. Further, when the counter data reaches 100,000 (when the guaranteed number of times is reached), the storage block for each digit in the distance number area C is shifted by 1 byte at P22. For example, if writing is OK at each of P4, P11, and P18, in other words, if there is no defective location in the distance number area C, each memory block is Shift bytes. Then, after shifting the memory blocks and writing data into the nonvolatile memory 24 in P22, the counter data of each memory block is rewritten in P23. That is, the counter data of the storage block that was previously used as a storage block for middle-order digit data is written in the lower-order digit area G of counter area B, and the counter data of the storage block that was previously used as a storage block for upper-order digit data is written in the middle-order digit area H. Write the counter data of the memory block that was previously stored, and write 0 to the upper digit area I. After updating the counter data in this way, the process returns to the input waiting state.

Next, the operation when the main switch 25 is turned off will be described in detail. The self-power-off circuit 23 detects whether the main switch 25 is turned on or off. When the main switch 25 is turned off, the process advances from S7 to S8 in FIG. Next, the cumulative number of pulses written in the non-volatile memory 24 is once read out in S9, and it is checked in S10 whether the data in the RAM 21 and the data in the non-volatile memory 24 match. In addition,
When the integrated pulse number is stored in the non-volatile memory 24 in S8, the fact that the counter data in the pulse number area D has been increased by 1 is stored in the RAM 21.

If the result of the determination in S10 is that the data do not match, it is determined that the memory block in the pulse number area D cannot be stored, and the memory block in the pulse number area D is shifted by one byte in S11. In other words, if there are defective locations indicated by D1 to D3 in the memory block of the pulse number area D in FIG.
Instead of using the memory blocks for bytes, the memory blocks above the defective location are used from the next time, as shown in (1) to (3) on the right side of the address map in FIG. After shifting the memory block in this manner, the counter data of the newly used memory block is changed to 0 in S12. At this time, the counter data in the pulse number area D is the pulse counter data area E in the counter area B.
will be written to. After changing the counter data in S12, the process returns to S8 to perform the cumulative pulse number storage operation again.

After it is confirmed in S10 that the data match, the cumulative mileage number is stored in the nonvolatile memory 24 in steps S13 to S17. This operation is almost the same as the memorization operation that is performed every 100 meters while driving. That is, the cumulative mileage number stored in the RAM 21 is stored in the nonvolatile memory 24 in S13, the data is once read out in S14, and the data is stored in the RAM 2 in S15.
Check if it matches the data in 1. If they do not match, the memory block in the distance number area C is shifted in S16, and the counter data is rewritten in S17. Thereafter, the cumulative mileage number is stored again. These series of operations are performed for each lower digit, middle digit, and upper digit.

After it is confirmed in S15 that the data match, the counter data of the distance number area C and the counter data of the pulse number area D are respectively stored. That is, in S18, the counter data of each data storage block is stored in the counter area B of the nonvolatile memory 24, and in S1
In step 9, the data is read once, and in step S20, it is checked whether it matches the data in the RAM 21. If it is not data, the storage area in counter area B is set to 1 in S21.
Shift only once. For example, if there are defective locations indicated by E1 to E2 in the pulse counter data area E in FIG. (1
) to (3), the memory blocks above the defective location will be used from next time onwards. Such a shift operation causes G1 to G2, H1 to H2,
The same process is carried out even when there are defective locations as indicated by I1 and I2. After shifting the storage area in count area B in this way, the process returns to S18 and the operation of writing the counter data is performed again.

As described above, after writing the respective count data in the storage area for storing the cumulative mileage number and the cumulative pulse number, the power is turned off in S22. At this time, the CPU 20 outputs a data storage end signal to the self-power-off circuit 23, and this self-power-off circuit 23
Power supply to the PU 20, nonvolatile memory 24, etc. will be cut off.

Therefore, according to the numerical data storage method of the present invention, numerical data is rewritten in data area A until the guaranteed number of rewrites is reached, and data is rewritten in data area A and counter area B while avoiding defective parts. It will be remembered.

In this embodiment, P4 and P11 in FIG.
, P18, when the result was NO, the process immediately proceeded to the next step (to P5, P12, P19), but when the result was NO, the user checked "Is writing OK?" several times. good.

[0031]Also, in this embodiment, an example was explained in which the number of traveled distances is stored using an odometer for a motorcycle, but the method for storing numerical data of the present invention is as shown in It can also be applied to an hour meter that totals the cumulative operating time of a machine. 9 and 10 are diagrams showing other embodiments, in which FIG. 9 is a block diagram of an hour meter that stores cumulative time using the numerical data storage method according to the present invention, and FIG. 10 is a flowchart showing the operation of the hour meter. . In these figures, the same or equivalent members as those explained in FIGS. 2 and 7 are given the same reference numerals, and detailed explanations are omitted here. In FIGS. 9 and 10, 41 is a timer circuit connected to the CPU 20, and 42 is a sensor that detects the rotational speed of the engine. In addition, display unit 1 used in this example
3a is one that displays the engine speed in three decimal digits and the cumulative operating time in six decimal digits. In an hour meter configured in this way,
The cumulative engine operating time is stored instead of the cumulative mileage. That is, the engine rotation speed detection sensor 42 generates one pulse per unit time during engine operation, and the cumulative operating time is calculated from the cumulative number of pulses. The cumulative operating time is then stored in the nonvolatile memory 24. Further, the pulse is configured to occur once every 25/1000 seconds. The method of writing the cumulative operating time, cumulative number of pulses, counter data, etc. into the non-volatile memory 24 is the same as in the previous embodiment, and therefore will not be described here. Note that step S in FIG.
7, when the main switch 25 is not turned off, the S
It is checked in step 7a whether or not the engine is rotating, and if the engine is rotating, the time is continued to be measured in step S7b, and if the engine is stopped, the time measurement is interrupted in step S7c. Even if the cumulative time is configured to be stored in this way, the same effect as in the embodiment described above can be obtained.

Furthermore, in this embodiment, the counter area B is roughly divided into four areas: the pulse counter data area E, the lower digit area G, the middle digit area H, and the upper digit area I. When the memory block existed, the memory block was shifted for each area, but it is also possible to shift the four areas at once as shown in FIG. 11. FIG. 11 is a diagram showing another embodiment of the numerical data storage method, and is an enlarged view of the counter area in the address map of the nonvolatile memory. When there is a defective location indicated by E1 in FIG. 11, as shown in (1) on the right side of the address map in FIG. Shift all storage areas. Similarly, when there is a defective location indicated by H1, it is shifted as shown in (2), and when there is a defective location indicated by I1, it is shifted as shown in (3).

[0033]

As explained above, the method for storing numerical data of an electronic totalizer according to the present invention has a data area for storing numerical data and a counter area for storing the number of times the numerical data has been rewritten in this data area. Numerical data and the number of times the numerical data has been rewritten are stored in a non-volatile memory that has separate storage areas, and when the number stored in the counter area reaches the guaranteed number of rewrites, When the data cannot be confirmed after reading the data, the numerical data and the number of rewrites of the numerical data are newly stored in the unused part of the storage area, so the data area is stored until the guaranteed number of rewrites is reached. Numerical data is rewritten and stored in the data area and counter area while avoiding defective areas. Therefore, it is possible to prevent numerical data from being rewritten more than the guaranteed number of rewrites, and it is also possible to prevent data from being written to a defective location, making it possible to obtain a highly reliable electronic totalizer.

[Brief explanation of drawings]

FIG. 1 is a side view of a motorcycle equipped with an electronic odometer employing the numerical data storage method according to the present invention.

FIG. 2 is a block diagram showing the configuration of an electronic odometer used to implement the numerical data storage method of the present invention.

FIG. 3 is a circuit diagram of a self-power-off circuit of an electronic odometer used to implement the numerical data storage method of the present invention.

FIG. 4 is a diagram showing an address map of a nonvolatile memory used in implementing the numerical data storage method of the present invention.

FIG. 5 is a diagram showing an enlarged data area of the address map shown in FIG. 4;

FIG. 6 is an enlarged view of a counter area of the address map shown in FIG. 4;

FIG. 7 is a flowchart showing a method for storing numerical data of an electronic odometer according to the present invention.

FIG. 8 is a flowchart showing the operation when storing mileage data in a nonvolatile memory.

FIG. 9 is a block diagram of an hour meter that stores cumulative time using the numerical data storage method according to the present invention.

FIG. 10 is a flowchart showing the operation of the hour meter.

FIG. 11 is a diagram showing another embodiment of the numerical data storage method, and is an enlarged view of the counter area in the address map of the nonvolatile memory.

[Explanation of symbols]

12 Electronic odometer 13 Display section 15 Control unit 16 Battery 20 CPU 21 RAM 22 Control unit 23 Self power off circuit 24 Non-volatile memory 25 Main switch

Claims (1)

[Claims] Claim 1. A numerical data storage method for an electronic totalizer in which numerical data stored in a non-volatile memory is rewritten and saved as new numerical data, a data area for storing numerical data, and a data area for storing numerical data. Numerical data and the number of times the numerical data has been rewritten are each stored in a non-volatile memory that has a storage area divided into a counter area that stores the number of times data has been rewritten, and the number stored in the counter area is the guaranteed number of rewrites. To newly store the numerical data and the number of times the numerical data has been rewritten in unused portions of the storage area, respectively, when the data area and the counter area are read once and the data cannot be confirmed. A method for storing numerical data of an electronic totalizer.