JPH02270195A - Data write device - Google Patents

Abstract

PURPOSE:To write data as many as possible in the range of the life of an EEPROM by providing plural data areas, etc., where the data are written, and when the number of times of write exceeds a reference number of times, prohibiting the data from being written to the data storage area. CONSTITUTION:EEPROMs (electrically erasable programmable read-only memory) 22a to 22n are divided into plural data storage areas 41a to 41n where the data are written, and write frequency storage areas 42a to 42n where the number of times of data write is stored. In addition the number of times of write is compared with the reference number of times set beforehand by a comparing means, and when that the number of times of the write has exceeded the reference number of times is decided, a prohibiting means is operated, and the write of the data to the data storage area 41i is prohibited. Thus the maximum data are written in the life range of the EEPROMs 22a to 22n.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is directed to an EEPROM' (e Electrical
y erasable programmab
The present invention relates to a data writing device having read-only memory, and particularly to a data writing device configured to prohibit writing to each of a plurality of data storage areas more than a reference number of times.

<Prior Art> Data writing devices that write or rewrite various data such as control program data into the EEPROM of a terminal device using a ROM rotor are used in various fields.

For example, the data writing device described above is also used in a remote monitoring device that centrally manages equipment such as air conditioners, lighting equipment, and water supply and distribution equipment installed in a building at a monitoring center.

That is, the terminal device of this type of remote monitoring device has EEP.
A computer with ROM is installed, and this EEP
Program data for application software for equipment is written into the ROM. The terminal device is connected to a monitoring center via a communication line, and the monitoring center is provided with a ROM rotor, and the ROM rotor writes program data for application software of the equipment into the EEPROM of the terminal device.

For example, since the control method for air conditioners is different in summer and winter, the monitoring center's ROM
By operating the rotor, the air conditioner's summer program data written in the EEPROM of the terminal device is erased.
Winter program data is written.

Such a remote monitoring device is described in Toyoda, Okuda; Dempa Kogyo (March 1980 issue, pp. 39-54).

Furthermore, when EEPROM memory is repeatedly erased and written, the memory reaches the end of its lifespan, and the reliability of the written data deteriorates.Furthermore, the data is destroyed, making it impossible to use it thereafter. So before the memory reaches the end of its lifespan,
Japanese Unexamined Patent Publication No. 61-59692 describes a memory card system that notifies an external party when the number of times data is written to an EEPROM exceeds a predetermined number so that the written data can be protected and rewritten to a new EEPROM. is proposed.

Therefore, if the technical idea related to this proposal is applied to the above-mentioned remote monitoring and control method, the program data of the equipment can be rewritten to the EEPROM of the terminal device without reducing the reliability of the data or destroying the data. However, it is possible to control and monitor equipment optimally in summer and winter.

<Problem to be solved by the invention> In the memory card system according to the above proposal, the EEPR
Each time data is written to OM, the number of writes is memorized.
Based on this stored number of times, a notification that writing is disabled is performed.

For this reason, when the data storage areas of the EEPROM are divided and used for each piece of equipment, for example, the number of times of writing is different in each data storage area, and the frequency of writing in each data storage area is different. For this reason, the maximum amount of writing within the EEPROM's lifespan is not possible, and a write-unable notification may be issued while a writable data storage area remains, which shortens the lifespan of the terminal device. There was a problem.

The present invention was made in view of the current state of this type of data writing device as described above, and its purpose is to write to an EEPROM having multiple storage areas to the maximum extent possible within the life span of the EEPROM. Do, E E P RO
An object of the present invention is to provide a data writing device that extends the life of a terminal device equipped with M.

Means for Solving the Problems> To achieve the above object, the present invention provides a terminal device having an EEPROM in which data can be written and erased, and a ROM for writing data into the EEPROM of this terminal device.
In the data writing device comprising a rotor, the E
An EPROM is divided into a plurality of data storage areas into which data is written, and a write count storage area which is provided corresponding to each of these data storage areas and stores the number of times data has been written to the corresponding data storage area. a comparison means for comparing the number of writes and a preset reference number for each write number storage area; and when the comparison means determines that the number of writes exceeds the reference number; The storage device has a prohibition means for prohibiting writing of data to the data storage area.

<Operation> According to the present invention, the EEPROM of the terminal device is provided with a plurality of data storage areas into which data is written and corresponds to these data storage areas, and the number of times data is written to each data storage area is stored. It is divided into a storage area for the number of writes.

When write data is input to the terminal device from the ROM rotor, the data is rewritten in the data storage area of the EEPROM where the data is stored, and the write count in the corresponding write count storage area is updated.

Furthermore, the comparison means for each data storage area compares the number of writes stored in the number of writes storage area with a preset reference number of times, and if it is determined that the number of writes exceeds the reference number, the prohibition means is activated and writing of data to that data storage area is prohibited.

In this way, data is written to each partitioned data storage area of the EEPROM of the terminal device, which has a different number of writes and a different write frequency, while comparing the number of writes with a preset reference number.
It is carried out to the maximum extent within the life span of M.

<Example> Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 3.

Here, FIG. 1 is a block diagram showing the configuration of the main part of the embodiment, FIG. 2 is an explanatory diagram showing the configuration of the EEPROM of the embodiment,
FIG. 3 is a flowchart showing the operation of the embodiment.

As shown in FIG. 1, the embodiment comprises a ROM rotor 1, a terminal device 2, and a cable 3 having an address bus 36 and a data bus 37 that connect the ROM rotor 1 and the terminal device 2 to each other.

The ROM rotor 1 includes an MPU 11, a ROM 12 in which operating programs of the MPU 11, etc. are stored, a RAM 13 in which data can be read and written, a ROM socket 14 into which a ROM 4 in which data to be written to the terminal device 2 is stored is installed. It has an input/output port 15, which are connected to each other by an address bus 16 and a data bus 17.

The terminal device 2 also includes an MPU 21, EEPROMs 22a to 22n in which data can be written and erased, a RAM 23 in which data can be read and written, and an interface 25, which are connected to each other by an address bus 26 and a data bus 27. , interface 25 and R
The input/output boats 15 of the OM rotor 1 are connected to each other by a cable 3.

As shown in FIG. 2, the above-mentioned EEPROM 22a includes a first partition range data storage area 40a to an n-th partition range data storage area 40n, a data storage area 41a, and a first partition write count storage area 42a to an n-th partition. It is divided into write count storage area 42n.

The first partition range data storage area 40a to the nth partition range data storage area 40a include EEPROMs 22a to EE.
Data indicating the partition range of PROM2'2n is written respectively. The data storage area 41a includes a ROM
Data from rotor 1 is written.

In addition, the number of times data is written to the data storage area 41a of the BEFROM 22a to the data storage area 41n of the EEPROM 22n is written in the first partition write count storage area 42a to the nth partition write count storage area 42n. ing. And EEPROM22b to EEPROM
22n are data storage areas 41b to 41 in which data from the ROM rotor 1 is written, respectively.
n is provided.

Next, the operation of the embodiment will be explained with reference to the flowchart in FIG.

In order to rewrite the control program of the equipment of the terminal device 2 in the ROM rotor 1, the ROM 4 in which the data of the new control program is written is transferred to the ROM of the ROM rotor 1.
Attach it to the socket 14.

When the ROM rotor 1 is operated in this state, data is input from the input/output boat 15 to the terminal device 2 from the interface 25 via the cable 3.

When data from the ROM 4 is input to the terminal device 2, in step S1 of the flowchart in FIG.
The writing range of data written in 4 is EEP, R
Confirmation is made as to which of the first partition range data storage area 40a to nth partition range data storage area 40n of the OM 22a corresponds to the written range, and step S2a
- Step S2n, whichever is confirmed.

For example, if it is assumed that the process has proceeded to step S2n, in step S2n, the MPU 21 writes the EEPROM 22
Data on the number of writes is read from the n-th section write number storage area 42n of a, and compared with a preset reference number n.

As a result of this comparison, if the write count data of the n-th partition write count storage area 42n is less than or equal to n, the data written in the EEPROM 22r17) data storage area 41n is erased in step S4, and the data stored in the ROM of the ROM rotor 1 is erased.
4 new data is written to the data storage area 41n.

Then, the process proceeds to step S5, where the number of writes in the n-th section write count storage area 42n of the EEPROM 22a is incremented by 1 and updated.

In step S1, if the write range of the data written in the ROM 4 does not belong to any of the ranges written in the above-mentioned first partition range data storage area 40a to nth partition range data storage area 40n. No processing is performed. Further, in step S2n, if the number of writes read from the aforementioned n-th partition write frequency storage area 42n exceeds the preset reference number N, writing to the aforementioned data storage area 41n is stopped. It is forbidden.

In this way, according to the embodiment, the EEPROM of the terminal device 2
is divided into n data storage areas 41a to 41n, and data writing is performed while comparing the number of times of writing to each data storage area with a preset reference number of times.
Since the process is performed efficiently and without waste to the maximum within the life span of the ROM, the life of the terminal device is extended.

In the embodiment, a configuration is described in which the range data storage area and the write count storage area for each storage area are all concentrated in one of a plurality of EEPROMs provided corresponding to the storage area. However, the present invention is not limited to the embodiments, and the range data storage area and the write count storage area may be provided in an EEPROM having corresponding storage areas.

<Effects of the Invention> As explained in detail above, according to the present invention, the EEPR
By effectively using a plurality of data storage areas provided separately in the OM, maximum data can be written within the life span of the EEPROM, thereby extending the operational life of the terminal device.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the main part of the embodiment of the present invention, FIG. 2 is an explanatory diagram showing the structure of the EEPROM of the embodiment of the present invention, and FIG. 3 shows the operation of the embodiment of the present invention. It is a flowchart. 1... ROM rotor, 2... terminal device, 3... cable, 4... ROM, 11
...MPU, 12...ROM, 13.
...RAM, 14...ROM socket,
15...Input/output boat, 21...MP
U, 22 a ~ 22 n-・-・E E P ROM
, 23...RAM, 25...Interface, 40a...First section range data storage area, 40n...Song/nth section range data storage area, 4
1a to 41n...data storage area. 1st Figure 1 ----FKDM rotor Saetsuji---Atoshiku bus 2---Mizumisousuke 37------Data bus 3---Cable

Claims (1)

[Claims] In a data writing device comprising a terminal device having an EEPROM in which data can be written and erased, and a ROM rotor for writing data to the EEPROM of this terminal device, the EEPROM has a plurality of data storages into which data is written. and a write count storage area that is provided corresponding to each of these data storage areas and stores the number of times data is written to the corresponding data storage area, and the number of writes and a preset standard number of times are stored. and a prohibition means for prohibiting writing of data to the data storage area when the comparison means determines that the number of writes exceeds the number of times. A data writing device comprising: