JPH06187205A - Method for accessing eeprom and surveying equipment - Google Patents

Abstract

PURPOSE:To greatly decrease the frequency of writing to the EEPROM. CONSTITUTION:When the power source is turned on, the file allocation table(FAT) and root director stored in the EEPROM 14 are copied to a main memory 12. Subsequent processing is carried out by accessing the FAT and root directory stored in the main memory 12 and when the power source is turned off, the FAT and root directory stored in the main memory 12 are written in the EEPROM 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an EEPROM access method and a surveying instrument.

[0002]

2. Description of the Related Art Conventionally, EEPROM (Electric)
all Erasable and Program
The data can be erased electrically in the same manner as data writing, and can be used as if it were a static RAM. Moreover, since it is a non-volatile memory, it can be used as a data memory in a logic circuit such as a microcomputer,
It is used in logic arrays that can rewrite logic.

[0003]

However, the EEPROM is
Has a limited number of writes, and was rarely used as a random access device. Also, M
Under S-DOS (“MS-DOS” is a trademark of Microsoft Corporation), the FAT (file allocation table) area and the root directory area are frequently written, so the number of writes is limited. A certain EEPROM has not been used as an external storage device of an OS (operating system).

The present invention has been made in view of the above circumstances, and it is a first object of the present invention to provide an EEPROM access method capable of significantly reducing the number of writing times of the EEPROM.

A second object of the present invention is to provide an EEPROM access method capable of repairing even if the FAT is destroyed.

A third object of the present invention is to provide an EEPROM access method capable of repairing a damaged root directory.

A fourth object of the present invention is to provide an EEPROM access method which can use the entire area of the EEPROM evenly.

A fifth object of the present invention is to provide a surveying instrument which can use the EEPROM as an external storage device without any trouble.

[0009]

The first EEPR of the present invention
The access method of the OM is to copy the file allocation table stored in the EEPROM to the main memory when the power is turned on, and perform the subsequent processing by accessing the file allocation table stored in the main memory. When the power is turned off, the file allocation table stored in the main memory is written in the EEPROM.

According to the second EEPROM access method of the present invention, when the power is turned on, the root directory stored in the EEPROM is copied to the main memory, and the subsequent processing accesses the root directory stored in the main memory. When the power is turned off, the root directory stored in the main memory is set to EEPR.
It is characterized by writing in the OM.

According to a third EEPROM access method of the present invention, for each file, a recovery table holding the first logical cluster number and the last logical cluster number of the corresponding file is stored in the EEPROM, and the recovery table is stored. The file allocation table is repaired based on the contents of the.

According to a fourth EEPROM access method of the present invention, a recovery table holding the file name of a corresponding file is stored in the EEPROM for each file, and the root directory is restored based on the contents of the recovery table. It is characterized by doing.

A fifth EEPROM access method of the present invention is provided with a cluster management table for storing a logical cluster number and a physical address which is a writing position of the EEPROM corresponding to the logical cluster number, and the EEPROM is provided.
Each time a logical cluster number for writing is given, the physical address for writing to the EEPROM is incremented, and the logical cluster number given for writing is added to the area of the cluster management table corresponding to the incremented physical address. It is characterized by storing.

According to a sixth EEPROM access method of the present invention, a cluster management table for storing a logical cluster number and a physical address which is a writing position of the EEPROM corresponding to the logical cluster number is provided, and the EEPROM is provided.
When a logical cluster number is already written in the target area of the cluster management table where the given logical cluster number should be written, the already written logical cluster number is not written in the cluster management table. By moving the storage position of the storage data of the corresponding EEPROM by moving it to a non-stored area, and then writing the logical cluster number given for writing in the EEPROM to the target area of the cluster management table. Is characterized by.

The first surveying instrument of the present invention comprises an EEPROM (eg, EEPROM 14 in FIG. 1) as an external storage device of the operating system, a main memory (eg, main memory 12 in FIG. 1), and an EEP when the power is turned on.
The file allocation table stored in the ROM is copied to the main memory, and when the power is turned off, the file allocation table stored in the main memory is copied.
Processing means for writing the table to the EEPROM (eg,
The CPU 8) of FIG. 1 is provided.

The second surveying instrument of the present invention comprises an EEPROM (eg, EEPROM 14 in FIG. 1) as an external storage device of the operating system, a main memory (eg, main memory 12 in FIG. 1), and an EEP when the power is turned on.
It is characterized by comprising a processing means (for example, CPU 8 in FIG. 1) for copying the root directory stored in the ROM to the main memory and writing the root directory stored in the main memory into the EEPROM when the power is turned off. .

[0017]

In the first EEPROM access method of the present invention, when the power is turned on, the file allocation table stored in the EEPROM is copied to the main memory, and the subsequent processing is performed by the file stored in the main memory. -The file allocation table stored in the main memory is stored in the main memory when the power is turned off by accessing the allocation table.
Written to EPROM. Therefore, the number of writings to the EEPROM can be greatly reduced.

In the second EEPROM access method of the present invention, the root directory stored in the EEPROM is copied to the main memory when the power is turned on, and the subsequent processing accesses the root directory stored in the main memory. When the power is turned off, the root directory stored in the main memory is written in the EEPROM. Therefore, EEPR
The number of writings to the OM can be significantly reduced.

In the third EEPROM access method of the present invention, the recovery table stored in the EEPROM holds, for each file, the first logical cluster number and the last logical cluster number of the corresponding file. . Therefore, the file allocation table can be restored based on the contents of the recovery table.

In the fourth EEPROM access method of the present invention, the recovery table stored in the EEPROM holds the file name of the corresponding file for each file. Therefore, the root directory can be restored based on the contents of the recovery table.

In the fifth EEPROM access method of the present invention, a cluster management table for storing a logical cluster number and a physical address which is a writing position of the EEPROM corresponding to the logical cluster number is provided.
Each time a logical cluster number for writing to the EEPROM is given, the physical address for writing to the EEPROM is incremented, and the logical cluster given for writing is written in the area of the cluster management table corresponding to the incremented physical address. The number is stored. Therefore, writing can be performed on the entire area of the EEPROM evenly.

In the sixth EEPROM access method of the present invention, a cluster management table for storing the logical cluster number and the physical address which is the writing position of the EEPROM corresponding to the logical cluster number is provided.
When the logical cluster number has already been written in the target area of the cluster management table to which the logical cluster number given for writing to the EEPROM should be written, the already written logical cluster number is written in the cluster management table. The logical cluster number given for writing to the EEPROM is written to the target area of the cluster management table after being moved to a non-stored area, and thus the storage position of the storage data of the corresponding EEPROM is moved. . Therefore, EEPRO
Writing can be performed on all areas of M on average.

In the first surveying instrument of the present invention, the processing means copies the file allocation table stored in the EEPROM to the main memory when the power is turned on and stores the file allocation table in the main memory when the power is turned off. Write file allocation table to EEPROM. Therefore, the processing after the power is turned on can be performed by accessing the file allocation table stored in the main memory.
Since the number of times of writing to M can be greatly reduced, the EEPROM can be used as an external storage device without any trouble.

In the second surveying instrument of the present invention, the processing means copies the root directory stored in the EEPROM to the main memory when the power is turned on, and copies the root directory stored in the main memory when the power is turned off. Write to EEPROM. Therefore, the processing after power-on can be performed by accessing the root directory stored in the main memory.
Since the number of writings to the OM can be greatly reduced, the EEPROM can be used as an external storage device without any trouble.

[0025]

1 shows the construction of an embodiment of a surveying instrument according to the present invention. The operation unit 2 is provided with buttons for powering on / off and buttons for performing various inputs for surveying. The input interface 4 sends a command or data corresponding to a button operation of the operation unit 2 via the bus 6.
It is supplied to the CPU 8. The CPU 8 performs processing according to the input command or data. ROM10 is CPU8
Stores the programs needed to perform processing.

The main memory 12 stores the processing result of the CPU 8 and the like. The EEPROM 14 is provided as an external storage device of MS-DOS. The ROM 10, the main memory 12, and the EEPROM 14 are connected to the CPU 8 via the bus 6.

The survey instrument interface 16 is a CPU 8
The various commands from are transmitted to the surveying instrument hardware 18, and the surveying instrument hardware 18 is caused to perform distance measurement, angle measurement, and the like. Further, the surveying instrument interface 16 sends the measurement result obtained by the surveying instrument hardware 18 to the CPU 8 via the bus 6. The CPU 8 obtains final distance measurement values and angle measurement values based on the sent measurement results and stores them in the main memory 12. The final distance measurement values and angle measurement values stored in the main memory 14 are
It is displayed on the LCD (liquid crystal display device) via the output interface 20. Further, the final distance measurement value and angle measurement value stored in the main memory 14 are stored in the EEPROM 14 according to an instruction from the operation unit 2, and are retained even after the power is turned off.

FIG. 2 is an explanatory diagram showing the memory configuration of the EEPROM 14 of FIG. EEPROM 31, bootstrap 31, FAT 32, root directory 3
3, the cluster management table 34, the first file F1, the second file F2 ...

FIG. 3 is an explanatory diagram showing an example of the contents of the FAT 32 of FIG. FAT is a table showing logical clusters assigned to each file. In the example of FIG. 3, the logical cluster C1 constitutes one file, the logical clusters C2, C3 and C4 constitute one file, the logical cluster C4 constitutes one file, and the logical cluster C5 is unused. Indicates that there is.

FIG. 4 is an explanatory diagram showing an example of the root directory 33 of FIG. In this example, the root directory area stores information such as file name, file size, date and time.

FIG. 5 shows the cluster management table 34 of FIG.
It is explanatory drawing which shows an example. Cluster management table 34
Is a table for storing a logical cluster number and a physical address (correctly, the head of the physical address in sector units) which is a writing position of the EEPROM 14 corresponding to the logical cluster number. A dedicated code is stored in the unused or deleted logical cluster area. In the example of FIG. 5, the information of the logical clusters C1, C2 and C3 is
Physical addresses S1 and S2 of the EEPROM 14, respectively
And S3 are stored. CPU8 is
Each time a logical cluster number for writing in the EEPROM 14 is given from the OS (operating system), the physical address for writing in the EEPROM 14 is incremented, and the writing is performed in the area of the cluster management table 34 corresponding to the incremented physical address. It stores the logical cluster number given for that purpose.
Further, when the logical cluster number has already been written in the target area of the cluster management table in which the logical cluster number given by the OS for writing to the EEPROM 14 should be written, the CPU 8 sets the already written logical cluster number. After moving to an area where nothing is written in the cluster management table and thereby moving the storage position of the corresponding storage data in the EEPROM 14, the logical cluster number given for writing in the EEPROM 14 is used for the purpose of the cluster management table. Write in the area. Therefore, even when overwriting, EEPRO
Since writing is not performed in the same sector of M14 but writing is performed in another sector, writing can be performed on all the clusters of the EEPROM 14 on average.

As shown in FIG. 2, a recovery table is provided at the end of each file. The recovery table uses FAT32 when each file is created.
And is created based on the information in the root directory 33 and written in the cluster next to the last cluster in the file. FIG. 6 is an explanatory diagram showing an example of the recovery table. In this example, the recover table has a file name, REVISION NO. , Attributes, the first logical cluster number and the last logical cluster number.

FIG. 7 is a flow chart showing an example of the processing when the power is turned on in the embodiment of FIG. The CPU 8 is shown in FIG.
FAT3 of the EEPROM 14 as shown in FIG.
2. Copy the root directory 33 and the cluster management table 34 to the main memory 12 (step S
1). Next, the CPU 8 uses the main memory 12 and the EEPR.
The FAT of the OM 14, the root directory, and the cluster management table are compared (step S2), and if they are different (NO in step S3), the recovery table added to each file is referred to and stored in the main memory 12. The FAT, root directory and cluster management table are repaired (step S4). Also, CP
If there is an incomplete file, U8 restores up to the previous sector as a file.

FIG. 8 is a flow chart showing an example of the repair processing step S4 of FIG. First, the CPU 8
The last logical cluster number of each file is acquired from the FAT 32 of the EPROM 14 (step S11). next,
The CPU 8 acquires the file name and attribute from the recover table of the cluster next to each logical cluster number acquired in step S11 (step S12).
Next, the CPU 8 restores the root directory of the main memory 12 from the file name and attribute acquired in step S12 (step S13). The directories do not have a hierarchical structure. If the same file name exists, REVISION N
O. Repair large files.

Next, the CPU 8 compares the logical cluster number obtained in step S11 with the corresponding cluster number of the FAT in the main memory 12 (step S14), and if they are different (NO in step S15), the EEPROM.
The last logical cluster number of the recover table 14 is copied to the FAT area of the main memory 12, and the FAT of the main memory 12 is restored (step S16). Then C
The PU 8 copies the first logical cluster number of the recovery table of the EEPROM 14 to the FAT area of the main memory 12 to restore the FAT of the main memory 12 (step S17).

In the embodiment of FIG. 1, the EEPROM 14
Writing of data to the memory is performed as follows. That is, the last area of the cluster management table stores the physical address of the EEPROM 14 to be written next, and the CPU 8 increments the physical address value of the last area by one each time writing occurs in the EEPROM 14. increase. The CPU 8 stores the logical cluster number passed from the OS in the last area of the cluster management table of the main memory 12, obtains the physical address of the EEPROM 14 corresponding to that area, and writes it in that area.

If a logical cluster number is already stored in the cluster management table, the CPU 8
The closest empty area is searched from that area, and the logical cluster number that has already been stored is moved to the empty area and the EE corresponding to that area is searched.
After moving the data to the physical address of PROM 14,
The logical cluster number passed from S is written in the cluster management table in the main memory and written in the EEPROM 14.

In the embodiment shown in FIG. 1, data reading is performed as follows. That is, the CPU 8
An area in which the logical cluster number passed from the device and the contents of the cluster management table match is searched for, the address of the EEPROM 14 assigned to the area is obtained, and the data of the obtained physical address is obtained from the EEPROM 14.

FIG. 10 is a flow chart showing an example of processing when the power is off in the embodiment shown in FIG. First, CPU8
Checks whether or not the FAT of the main memory 12, the root directory, and the area of the cluster management table are changed after the power is turned on (step S21). If there is a change, as shown in FIG. , The FAT of the main memory 12, the root directory, and the cluster management table are written in the corresponding areas of the EEPROM 14 (step S22). However, the writing position of the EEPROM 14 is the sector next to the sector in which the writing is performed before the power-off processing. By doing this, EE
Writing to each area of the PROM 14 can be more averaged.

Although the above-described embodiment operates under the MS-DOS, the present invention is not limited to this and can be carried out under various operating systems.

[0041]

According to the first EEPROM access method of the present invention, when the power is turned on, the file allocation table stored in the EEPROM is copied to the main memory, and the subsequent processing is stored in the main memory. The file allocation table stored in the main memory when the power is turned off.
Since it was written to EPRROM, EEPROM
It is possible to significantly reduce the number of times of writing to.

According to the second EEPROM access method of the present invention, when the power is turned on, the root directory stored in the EEPROM is copied to the main memory, and the subsequent processing is performed by copying the root directory stored in the main memory. It is done by accessing and when the power is off,
E is the root directory stored in the main memory
Since the writing is performed in the EPROM, the number of writings in the EEPROM can be significantly reduced.

According to the third EEPROM access method of the present invention, the recovery table stored in the EEPROM holds, for each file, the first logical cluster number and the last logical cluster number of the corresponding file. The file allocation table can be repaired based on the contents of the recovery table.

According to the fourth EEPROM access method of the present invention, since the recovery table stored in the EEPROM holds the file name of the corresponding file for each file, the contents of the recovery table You can repair the root directory based on.

According to the fifth EEPROM access method of the present invention, the cluster management table for storing the logical cluster number and the physical address which is the writing position of the EEPROM corresponding to the logical cluster number is provided and the EE is provided.
Each time a logical cluster number for writing in the PROM is given, the physical address for writing in the EEPROM is incremented, and the logical cluster given for writing in the area of the cluster management table corresponding to the incremented physical address. Since the numbers are stored, the data can be written in the entire area of the EEPROM evenly, and the usable capacity of the EEPROM can be prevented from decreasing.

According to the sixth EEPROM access method of the present invention, a cluster management table for storing a logical cluster number and a physical address which is a writing position of the EEPROM corresponding to the logical cluster number is provided, and the EEPROM is provided.
When the logical cluster number is already written in the target area of the cluster management table where the logical cluster number given for writing in the ROM should be written, the already written logical cluster number is written in the cluster management table. Then, after moving the storage position of the storage data of the corresponding EEPROM, the logical cluster number given for writing to the EEPROM is written to the target region of the cluster management table. Therefore, it is possible to write data to the entire area of the EEPROM on average.
It is possible to prevent the usable capacity of M from decreasing.

According to the first surveying instrument of the present invention, the file allocation table stored in the EEPROM is copied to the main memory when the power is turned on, and the file allocation stored in the main memory when the power is turned off. Since the processing means for writing the table in the EEPROM is provided, the processing after the power is turned on can be performed by accessing the file allocation table stored in the main memory.
It is possible to significantly reduce the number of times of writing to. Therefore, the EEPROM can be used as an external storage device without any trouble.

According to the second surveying instrument of the present invention, the root directory stored in the EEPROM is copied to the main memory when the power is turned on, and the root directory stored in the main memory is copied when the power is turned off.
Since the processing means for writing the data into the main memory is provided, the processing after the power is turned on can be performed by accessing the root directory stored in the main memory.
The number of writings to the OM can be significantly reduced. Therefore, the EEPROM can be used as an external storage device without any trouble.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a surveying instrument of the present invention.

FIG. 2 is an explanatory diagram showing a memory configuration of an EEPROM 14 of FIG.

FIG. 3 is an explanatory diagram showing an example of contents of a FAT 32 shown in FIG.

FIG. 4 is an explanatory diagram showing an example of a root directory 33 of FIG.

5 is an explanatory diagram showing an example of a cluster management table 34 of FIG.

FIG. 6 is an explanatory diagram showing an example of a recovery table of FIG.

FIG. 7 is a flowchart showing an example of processing when the power is turned on in the embodiment of FIG.

8 is a flowchart showing an example of a repair processing step S4 of FIG.

9 is an explanatory diagram showing a data flow of processing when the power is turned on in the embodiment of FIG. 1. FIG.

10 is a flowchart showing an example of processing when the power is off in the embodiment of FIG.

FIG. 11 is an explanatory diagram showing a data flow of processing when the power is off in the embodiment of FIG. 1;

[Explanation of symbols]

 2 Operation part 4 Input interface 8 CPU 12 Main memory 14 EEPROM 16 Surveyor interface 18 Surveyor hardware 20 Output interface 22 LCD

Claims (12)

[Claims] 1. When the power is turned on, the file allocation table stored in the EEPROM is copied to the main memory, and the subsequent processing is performed by accessing the file allocation table stored in the main memory. The file allocation table stored in the main memory is stored in the EEPR when the power is turned off.
An EEPROM access method characterized by writing to an OM. 2. When the contents of the file allocation table stored in the main memory at power-off are the same as the contents of the file allocation table at power-on, a file allocation table is displayed.
2. The EEPROM access method according to claim 1, wherein the table is not written in the EEPROM. 3. The cluster of the EEPROM to which the file allocation table is written when the power is turned off is a cluster next to the cluster written before the power-off processing. Item 1. An EEPROM access method according to Item 1. 4. A recovery table, which holds the first logical cluster number and the last logical cluster number of the corresponding file for each file, is stored in the EEPROM, and the file allocation file is stored based on the contents of the recovery table. EE characterized by repairing the table
How to access PROM. 5. When the power is turned on, the root directory stored in the EEPROM is copied to the main memory, and the subsequent processing is performed by accessing the root directory stored in the main memory. A method for accessing an EEPROM, characterized in that a root directory stored in a memory is written in the EEPROM. 6. When the power is turned off, when the contents of the root directory stored in the main memory are the same as the contents of the root directory when the power is turned on, the root directory is not written to the EEPROM. The method for accessing the EEPROM according to claim 5. 7. The cluster of the EEPROM to which the root directory is written at power-off is a cluster next to the cluster written before the power-off processing. EEP
ROM access method. 8. An access to the EEPROM, wherein a recovery table holding the file name of the corresponding file is stored in the EEPROM for each file, and the root directory is restored based on the contents of the recovery table. Method. 9. A cluster management table for storing a logical cluster number and a physical address which is a writing position of the EEPROM corresponding to the logical cluster number is provided, and each time a logical cluster number for writing the EEPROM is given, A physical address for writing to the EEPROM is incremented, and a logical cluster number given for the writing is stored in an area of the cluster management table corresponding to the incremented physical address. how to access. 10. A cluster management table for storing a logical cluster number and a physical address which is a writing position of the EEPROM corresponding to the logical cluster number is provided, and the logical cluster number given for writing to the EEPROM is written. When the logical cluster number has already been written in the target area of the appropriate cluster management table, the already written logical cluster number is moved to an area in which nothing is written in the cluster management table to store the corresponding EEPROM. A method for accessing an EEPROM, characterized in that, after moving a data storage position, a logical cluster number given for writing in the EEPROM is written in a target area of a cluster management table. 11. An EEPROM as an external storage device of an operating system, a main memory, and a file allocation table stored in the EEPROM when the power is turned on, are copied to the main memory, and are stored in the main memory when the power is turned off. The stored file allocation table is stored in the EEPRR.
A surveying instrument comprising: a processing unit for writing in the OM; 12. An EEPROM as an external storage device of an operating system, a main memory, and a root directory stored in the EEPROM when the power is turned on are copied to the main memory and stored in the main memory when the power is turned off. A surveying instrument, comprising: a processing unit for writing the existing root directory into the EEPROM.