JP3271935B2 - Control system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control system having a flash memory for storing data such as setting data indicating the setting of a control device and status data indicating a control state.

[0002]

2. Description of the Related Art As a control system of this kind, for example, there is a control system used for controlling lighting equipment. In this control system, a setting such as which lighting equipment is turned on at a certain operation and at what output level is performed. It is necessary to store data and status data indicating the status of the lighting equipment, such as the output level of the lighting equipment and the timer time until output switching. By the way, if stored data such as setting data and status data is lost when a power failure occurs, it will not be possible to set the control system and reproduce the control state after the power failure is recovered. It was stored in a non-volatile memory.

[0003] In recent years, flash memories have become the mainstream of non-volatile memories. When data is written to a specific address in a flash memory, if the data has already been written to the same address, the value of the data is In some cases, new data cannot be written without first erasing the data. In addition, in the flash memory, the memory space is divided into a plurality of sectors as a fixed storage / erasing unit, and data erasing operation cannot be performed in byte units, but only in sector units.

Therefore, when rewriting management of data stored in the flash memory is performed, if specific data is managed at a specific address in the memory, such as a RAM or an E ² PROM, even if only one byte of data is rewritten, the data is not rewritten. If the data changes arbitrarily, once every two times
It is necessary to write new data after erasing already written data, save the data in sector units, and after erasing the data in this sector, write the saved data back to this sector. This requires a lot of time to write data into the flash memory, resulting in a loss in time. In addition, since the number of times of rewriting of the sector is increased, the life of the flash memory is shortened.

Therefore, when performing data rewrite management using a flash memory as a storage medium, when updating certain data, it is not necessary to overwrite old data written in the flash memory with new data, but to update the flash memory. New data is written in the unused area, and the pointer to the old data is discarded by the program of the interface unit that writes and reads the data to and from the flash memory, and the pointer to the new data is stored.

When the unused area in the sector is exhausted when writing new data to the flash memory, only valid data to which a pointer is connected in the original sector to be copied is transferred to another unused sector. Unnecessary data in the source sector to which the pointer is not connected is discarded, and an unused area is created in the write destination sector (hereinafter, this operation is referred to as garbage collect). Even if the used area is exhausted, data can be stored continuously. It should be noted that the data in the original sector to be copied is erased and reproduced in an unused sector.

For example, as shown in FIG. 9A, in a state where three data A, B, and C are stored in blocks 1, 3, and 2 which are storage units of a sector X, the data A is stored. When updating, as shown in FIG. 9B, the interface unit (not shown) writes the new data A to the unused block 4 of the sector X, and pointers to the old data A stored in the block 1. Is discarded, and the pointer to the new data A stored in the block 4 is stored in the pointer table.

FIG. 9C shows a case where the data A and C are updated in a state where the three data A, B and C are stored in the blocks 4, 3 and 2 of the sector X, respectively. As described above, the interface unit writes the new data A and C into the unused blocks 5 and 6 of the sector X, discards the pointers to the old data A and C, and
Is stored in the pointer table.

Thereafter, when the data C is updated, new and old data are written in all the blocks 1 to 6 of the sector X, and the unused area of the sector X is lost.
As shown in (d), the interface unit is provided for the sector X.
Of the blocks A, B, and C to which the pointers are connected, are copied to the blocks 1, 2, and 3 of the unused sector Y, and the blocks 1 and 6 to which the pointers are not connected. Unused data 2 and 4 are discarded, and unused blocks 4 to 6 are provided in sector Y. At this time,
The interface unit erases the data of the sector X to be copied and reproduces the data in an unused sector.

[0010] By the way, by adding a code for identifying the stored contents and information indicating the validity / invalidity of the stored contents to the stored contents written in the flash memory, when returning after a power failure occurs, , The storage contents of the flash memory can be identified and read.

[0011]

In the control system having the above-mentioned configuration, when updating certain data already written in the flash memory, an unused area in a sector disappears, and a power failure occurs during garbage collection. When this occurs, there is a problem that it is not possible to determine which of the source sector and the destination sector is valid data depending on the timing of the power failure.

Further, when updating certain data already written in the flash memory, if a power failure occurs while new data is being written to an unused area in a sector, depending on the timing of the power failure, Another problem is that the interface unit cannot determine which of the newly written data and the old data is valid data.

Furthermore, when data is saved to the flash memory in an emergency such as a power outage, there is no unused area in the sector, and if garbage collection is performed, it takes time to copy the data. There was also a problem that evacuation might not be in time. In addition, when unused areas in a sector are lost and data is written to another unused sector, it is preferable to use each sector as evenly as possible in order to extend the life of the sector. In addition, since the number of times of use of each sector cannot be determined, there is a problem that each sector cannot be used evenly.

Furthermore, when the power is turned on to the system, the flash memory is in an undetermined state of data immediately after shipment or has been initialized, and a state in which data has already been stored after recovery from power failure. There was also a problem that it was impossible to tell what it was. The present invention has been made in view of the above problems, and an object of the present invention is to provide a control system that can easily determine a writing state for each memory erasing unit.

It is another object of the present invention to provide a control system which can easily determine a writing state for each storage unit of storage data in addition to the above-mentioned objects. A third object of the present invention is to provide a control system capable of reliably saving data in an emergency in addition to the above objects. The object of the invention of claim 4 is, in addition to the above object,
An object of the present invention is to provide a control system for extending the life of a flash memory.

Another object of the present invention is to provide a control system which can easily determine whether or not a flash memory has been initialized.

[0017]

In order to achieve the above object, an electrically rewritable flash memory in which a memory space is divided into a plurality of storage erasure units and data is erased for each storage erasure unit, An interface unit for writing and reading data to and from a memory, wherein a first write state storage area for storing write state information indicating a data write state for each storage erase unit is provided in the flash memory; The unit writes only valid data in the storage erasing unit to another unused storage erasing unit when there is no free space in the storage erasing unit when writing data to any of the storage erasing units. , Data write start time, write completion time,
At the time when the data of the memory
At the point when the data of the memory erase unit of the copy source is used
Since the write state information in the first write state storage area is updated, the interface unit
From the write state information written in the write state storage area of
The current writing state of the corresponding storage erasure unit can be grasped.

According to a second aspect of the present invention, in the first aspect of the present invention, a plurality of storage units to which data is written and write state information indicating a data write state of each storage unit are stored in the storage erase unit. A second write state storage area, and the interface unit updates the write state information of the second write state storage area when the data write state of each storage unit changes. The unit can grasp the write state of data to each storage unit from the write state information written in the second write state storage area.

According to a third aspect of the present invention, in the first or the second aspect of the present invention, the interface unit further includes an application unit for outputting instruction data for instructing data writing and reading, and the emergency response to the instruction data from the application unit is provided. When the emergency code shown is included, the interface unit writes data in an unused emergency write storage / erasure unit different from the storage erase unit normally written. When data is evacuated in an emergency, there is no free space in the memory erasure unit, and if garbage collection is performed, data may not be able to be written in time. Since the data is saved, it is possible to prevent a situation in which data writing cannot be performed in time.

According to a fourth aspect of the present invention, in the first to third aspects of the present invention, a counter area for storing the number of times of use of the storage erasure unit is provided for each storage erasure unit. Since the number of uses stored in the counter area is counted up and written in the counter area, the interface unit can grasp the number of uses of the storage erase unit from the number of uses written in the counter area.

According to a fifth aspect of the present invention, in the first to fourth aspects of the present invention, an initialized code area for storing an initialized code indicating whether or not the flash memory has been initialized is provided in the flash memory. Writes the initialized code in the initialized code area when the flash memory is initialized and when erasing data in the storage erasing unit, the interface unit is initialized in the initialized code area. It is possible to determine from the code whether the flash memory has been initialized.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a schematic configuration diagram of a control system according to the present embodiment. The control system includes a lighting control device 10 for controlling a lighting state of a lighting fixture and a setting for setting setting data such as which lighting fixture is to be turned on at what output level for which operation in a memory unit 13 described later. Lighting control device 1 via device 11 and communication line 12
0 and connected to the setting device 11 to store state data such as a lighting output of the lighting fixture and a timer time until output switching transmitted from the lighting control device 10 and data such as setting data set by the setting device 11. And a memory unit 13.

The memory unit 13 includes a transmission processing unit 14 for exchanging signals with the illumination control device 10 and the setting device 11 via the communication line 12 and a power failure detection unit 15 for detecting a stop of power supply due to a power failure or the like. And an application unit 16 that outputs instruction data for instructing writing and reading of data to and from a flash memory 18, which will be described later, based on a signal received via the transmission processing unit 14 and a detection signal of the power failure detection unit 15.
An interface unit 17 for writing data to and reading data from the flash memory 18 based on the instruction data input from the application unit 16;
It comprises an electrically rewritable flash memory 18 in which data such as setting data and status data is written and read by the interface unit 17.

As shown in FIG. 2, the memory space of the flash memory 18 is divided into, for example, ten sectors (Secta) 19 _{0, which} are storage erasure units, and a program storage sector 19 for storing a program. _0, and data storage sectors 19 ₁ for storing data such as setting data and status data. The data storage sector 19 ₁ ... includes a sector 19 ₁ ... capacity of 64K bytes, sectors 19 ₈ a capacity of 8K bytes, 19 ₉ and is provided, set in the sector 19 ₁ ... 64K bytes of Data is stored in an 8 Kbyte sector 19 ₈ , 1
The state data ₉ is stored in ₉ .

Sector 19 to which setting data is written_ThreeIs
It comprises a management unit 20 and a data unit 27, and the data unit 27
Up to 256 bytes of data can be stored respectively
Block of 254 storage units (Block) 28₁, 28
_Two… 28₂₅₄Consists of On the other hand, the management unit 20
The sector management unit 21, which is a write state storage area for the
K28₁, 28_Two… 28₂₅₄Provided for each
Index 24 as second write state storage area₁, 24
_Two… 24₂₅₄And the sector management unit 21
Sector 19_ThreeIndicates what content is used for the data
Content code CODE₁And this sector 19_ThreeData to
Status information indicating the write status (sector use status) of the
The sector status data 23 is written. In addition,
Index 24₁, 24_Two… 24₂₅₄Has the corresponding
Lock 28₁, 28_Two… 28₂₅₄What data is
Content code CODE indicating whether it is stored_TwoAnd corresponding
Block 28₁, 28_Two… 28₂₅₄Writing data to
Status information indicating the write status (block use status)
The block status data 26 is written. In addition, each
Sector 19₀.. Are stored in the flash memory 18.
Initialized code is written to indicate whether or not is already initialized
Writes the initialized code area and the number of times each sector has been used
A counter area is provided. Also, state data
Sector 19 to which is written₈Contains 16 bytes of data
508 blocks 28 that can store ₁, 28_Two… 28
₅₀₈And 508 insets provided for each block.
Index 24₁, 24_Two… 24₅₀₈And is provided
You. Block 28₁… And index 24₁... after
The outer configuration is the same as the sector 19 described above._ThreeIs the same as
Description is omitted.

The interface section 17 shows the correspondence between the data content codes CODE ₁ and CODE ₂ and the sectors and blocks to which the data is written in order to manage the data write destination in the flash memory 18. A data position search table (Table 1) and a sector status / last used block list (Table 2) indicating the use state (in use or unused) of each sector and the number of the last used block of each sector are provided. . For example, according to Table 1, sectors 191 to 193 having any one of numbers _{1 to 3} are assigned to the content codes CODE ₁ = 1 and 2, and the content code CO
Sector 1 of any of numbers 8 and 9 for DE ₁ = 3
9 _8, 19 ₉ are assigned. And the content code C
_{One of the} blocks 28 ₁ ... Is assigned to the ODE ₂ . Therefore, the interface unit 17 can easily retrieve the data of the content codes CODE ₁ and CODE ₂ designated from Table 1 in which block of which sector. Also, the interface unit 17
Can read the sector in use and the number of the last used block from Table 2 and determine the next available block number when writing data.

[0027]

[Table 1]

[0028]

[Table 2]

The interface unit 17 is a flash memo
Code CODE of data to be written to the memory 18₁, CO
DE_TwoTable 3 shows the relationship between and the contents. Flash memo
3A to 3I are data to be written to the file 18.
As shown in the figure, a maximum of 256 loads y (y = 1 to 25)
6) and up to 16 extended loads z (z = 1 to 16)
Pattern x registration data for lighting in a fixed pattern
D₁(X = 1 to 72) and the load y in each pattern
Pattern x level data D for setting dimming level
_Two(X = 1 to 72), load y (y = 1 to 256) and
Expanded load z (z = 1 to 16) collectively for each predetermined group
G registration data D for turning on and off_Three
Setting data such as (g = 1 to 127) and each group
Group on / off state data D indicating the on / off state of
_FourAnd timers for turning on or delaying off lights for each group
-Group timer status data D indicating whether or not operation is in progress
_FiveOr for each load y (y = 1 to 128, 129 to 256)
Indicates the load timer status data (previous
Half) D₆, Load timer status data (second half) D₇And each extension
Indicates whether or not the timer is operating for each tension load z (z = 1 to 16)
Extended load timer status data D₈And the current
Extended load level status data D indicating the current dimming level ₉What
Which has state data.

Here, as shown in Table 3, each pattern x
The registration data D ₁ (x = 1 to 72) contains the content code COD
E ₁ = 1 and CODE ₂ = 1 to 72 are respectively assigned,
Content codes CODE ₁ = 1 and CODE ₂ = 73 to 144 are assigned to each pattern x-level data D ₂ (x = 1 to 72), respectively. Each group g registration data D ₃ (g = 1 to 127) has a content code CODE ₁ =
2, CODE ₂ = 1 to 127 are assigned respectively. The status data D _{4 to} D ₉ include the content code CO
DE ₁ = 3 is assigned, group on / off state data D ₄ , group timer state data D ₅ , load timer state data (first half) D ₆ , load timer state data (second half)
D ₇ , extended load timer status data D ₈ , and extended load level status data D ₉ include content codes CODE ₂ = 1 to 6, respectively.
Is assigned. As described above, the data written to the flash memory 18 corresponds to the content codes CODE ₁ and CODE ₂ indicating the types of data, respectively, and the application unit 16 collectively stores these data in the flash memory 18. The command data is output to the interface unit 17 so as to be written.

[0031]

[Table 3]

The operation of this control system will now be described with reference to FIG.
This will be described according to the flowchart of FIG. At system startup,
The interface unit 17 determines whether the flash memory 18 has been initialized (step 50). If the initialized code the initialized coding region of the sector in the flash memory 18 is not written, the interface unit 1
7 determines that the flash memory 18 has not been initialized, and waits for instruction data from the application unit 16 (step 52). On the other hand, if the initialized code has been written in the initialized code storage area of the sector of the flash memory 18, the interface unit 17 determines that the flash memory 18 has already been initialized, and writes the data to the flash memory 18. The above-described data position search table and the like are created from the data (step 51), and instruction data from the application unit 16 is waited for (step 5).
2).

In step 53, the interface unit 17
When instruction data for confirming the state of the flash memory 18 (whether the flash memory 18 has been initialized) is input from the application unit 16 to the interface unit 17, the interface unit 17 sends to the application unit 16 data indicating whether the flash memory 18 has been initialized. Is returned (step 54), and the application unit 1
Wait for the next instruction data from step 6 (step 52).

After confirming whether or not the flash memory 18 has been initialized, the application unit 16 sends instruction data for initializing the flash memory 18 to the interface unit 1 if the flash memory 18 has not been initialized.
7 is output. In step 53, the interface unit 1
7 is the flash memory 1 from the application unit 16
When the instruction data for initializing the flash memory 18 is received, the entire data area of the flash memory 18 is erased and the flash memory 1 is erased.
8 is initialized (step 55), a default storage destination is allocated (step 56), and the above-described data position search table and the like are created (step 57), and the initialized code is stored in the initialized code area of the flash memory 18. (Step 58), and waits for the next instruction data from the application unit 16 (step 52).

As described above, the application unit 16
Based on the initialized code written in the initialized code area of the flash memory 18, the flash memory 18
It is determined whether or not the flash memory 18 has been initialized. If the flash memory 18 has not been initialized, the interface unit 17 has initialized the flash memory 18 based on the instruction data from the application unit 16. Is not initialized, a default storage destination is assigned, a write error occurs, a malfunction occurs when an attempt is made to create a data position search table or the like from the uninitialized flash memory 18, or the initialization is performed. The used flash memory 18 will not be initialized by mistake.

Further, the user operates the setting device 11 to
For example, when setting the pattern 72 registration data, the transmission processing unit 14 receives the pattern 72 registration data transmitted from the setting device 11 via the communication line 12 and outputs the pattern 72 registration data to the application unit 16. The application unit 16 transmits the pattern 7 from the transmission processing unit 14.
2 When the registration data is input, the data
2 Content code CODE ₁ indicating registration data =
1. A signal in which CODE ₂ = 72 is added to the pattern 72 registration data is output to the interface unit 17 as instruction data, and a write request is made.

In step 53, the interface unit 17
When the write request instruction data is input from the application unit 16 to the interface unit 17, the interface unit 17 determines the write destination of the pattern 72 registration data from the content code (CODE ₁ = 1, CODE ₂ = 72) and the data position search table. A sector and a block are selected (step 59), and it is determined whether or not there is an empty block in the write destination sector (step 60).

If there is an empty block in the write destination sector, the interface unit 17 executes the flash memory writing subroutine shown in the flowchart of FIG. 5 (step 62), and the next instruction from the application unit 16 is issued. It waits for data (step 52). Less than,
The operation at the time of writing to the flash memory will be described with reference to FIGS. At the point in time before the start of writing of new data (time t _{1 in} FIG. 6), block status data (for example, 1000) indicating “running” (RUNNING) is written in the index corresponding to the block in which the old data has been written. , The index corresponding to the block to write new data to,
Block status data indicating erasure (ERASED) (for example, 11
11) is written, and no data is stored in the block to which new data is written. Therefore,
If a power failure occurs at this point, the old data block in which the block status data indicating the operation is being written becomes valid, and the old data is used when the power is restored.

In the flash memory writing subroutine, the interface unit 17 stores, in the index corresponding to the block in which the new data is to be written, a content code indicating the content of the new data and a block state indicating that writing is in progress (WRITING). Data (for example, 1110) is written (step 65). At this time (time t _{2 in} FIG. 6), the block status data indicating the operation is written in the index corresponding to the block in which the old data is written, and the index corresponding to the block in which the new data is written is
Block status data indicating that writing is in progress has been written,
The data of the block to which the new data is to be written has not been determined. Therefore, if a power failure occurs at this time, the old data block in which the block status data indicating the operation is being written becomes valid, and the old data is used when the power is restored.

Thereafter, the interface unit 17 writes new data in the block in which the new data is to be written (step 66), and writes block status data (for example, 1100) indicating write completion (WROTE) in the index corresponding to this block. (Step 67). At this time (time t _{3 in} FIG. 6), the block status data indicating the operation is written in the index corresponding to the block in which the old data is written, and is written in the index corresponding to the block in which the new data is written. The block status data indicating completion is written, and the data of the block in which the new data has been written is determined. Therefore, if a power failure occurs at this time, the new data block in which the block status data indicating the completion of writing is written becomes valid, and the new data is used when the power is restored.

Next, the interface unit 17 determines whether or not there is old data (step 68). If there is old data, it is used (USED) for the index corresponding to the block in which the old data has been written. Is written (step 69). At this time (time t _{4 in} FIG. 6), the block status data indicating used is written in the index corresponding to the block in which the old data has been written, and the index is written in the index corresponding to the block in which the new data has been written. Block status data indicating completion has been written, data of the block to which old data has been written has disappeared, and data of the block to which new data has been written has been determined. Therefore,
If a power failure occurs at this point, the new data block in which the block status data indicating the write completion is written becomes valid, and the new data is used when the power is restored. After that, the interface unit 17 writes the block status data indicating that it is in operation to the index corresponding to the block in which the new data has been written (step 70). On the other hand, if there is no old data, the process proceeds to step 70 and the interface unit 1
Reference numeral 7 writes block status data indicating that operation is in progress to an index corresponding to the block in which the new data has been written.

As described above, when data is written to a free block in a sector, the interface unit 17 is writing to the index corresponding to the block in which new data is to be written, and is a block state indicating a write state such as writing completed. Since data is being written, even if a power failure occurs at any point during writing, the interface unit 17 can easily determine from the block state data which block data should be used as the latest data when the power is restored. it can.

If it is determined in step 60 whether or not there is an empty block in the write destination sector, and there is no empty area in the write destination sector, the interface unit 17
Executes the garbage correct subroutine shown in the flowchart of FIG. 7 (step 61), and then proceeds to the flash memory writing subroutine of step 62.

In the garbage collect subroutine,
First, the interface unit 17 includes a flash memory 18.
The sector with the least number of uses is selected as a destination sector (hereinafter referred to as a new sector) from among the unused sectors (step 71). At this point (time t in FIG. 8)
₁₁ ) Sector status data (for example, 1000) indicating operation (RUNNING) is written to the sector management unit of the currently used sector (hereinafter, referred to as the old sector), and erase ( ERASED) has been written, and no data is stored in the new sector. Therefore, if a power failure occurs at this time, the old sector in which the sector status data indicating the operation is being written becomes valid, and the old sector is used when the power is restored.

Next, the interface unit 17 writes the content code indicating the content of the data to be written and the sector status data (for example, 1110) indicating the writing (WRITING) to the sector management unit of the new sector (step 72). ). At this point in time (time t _{12 in} FIG. 8), the sector status data indicating the operation is written in the sector management unit of the old sector, and the sector status data indicating the writing is written in the sector management unit of the new sector. The data of the new sector has not been determined. Therefore, if a power failure occurs at this time, the old sector in which the sector status data indicating the operation is being written becomes valid, and the old sector is used when the power is restored.

Thereafter, the interface unit 17 copies only the data of the block in which the block status data indicating the operation is written in the corresponding index to the new sector (step 73), and completes the writing to the sector management unit of the new sector (step 73). WROTE) Sector status data (eg, 1100)
Is written (step 74). At this time (time t in FIG. 8)
_{In 13} ), the sector status data indicating the operation is written in the sector management unit of the old sector, and the block status data indicating the completion of writing is written in the sector management unit of the new sector, and the data of the new sector is determined. ing. Therefore, if a power failure occurs at this time, the new sector in which the sector status data indicating the completion of writing is written becomes valid, and the new sector is used when the power is restored.

Next, the interface unit 17 writes sector status data (for example, 0000) indicating used (USED) to the sector management unit of the old sector (step 75). In this point (time t ₁₄ in FIG. 8), the sector status data indicating a dirty sector management of the old sector is written, and the block status data indicating the completion of writing to the sector management section of the new sector is written , The data of the old sector has been lost, and the data of the new sector has been determined. Therefore, if a power failure occurs at this time, the new sector in which the sector status data indicating the completion of writing is written becomes valid, and the new sector is used when the power is restored.

Further, the interface unit 17 writes sector status data indicating that the sector is in operation to the sector management unit of the new sector (step 76). In this point (time t ₁₅ in FIG. 8), the sector status data indicating a dirty sector management of the old sector is written, and the block state data indicating in operation to the sector management section of the new sector is written, The data of the old sector has been lost, and the data of the new sector has been determined. Therefore, if a power failure occurs at this time, the new sector in which the sector status data indicating that the operation is in progress is valid, and the new sector is used when the power is restored.

Thereafter, the interface unit 17 reads the number of times of use stored in the counter area of the old sector (step 77), deletes the data of the old sector (step 78), and adds 1 to the number of times of use of the old sector. The written value is written to the counter area of the old sector (step 79), and the initialized code is written to the initialized code area of the old sector (step 80).

As described above, when there is no free block in the sector and garbage collection is performed, the interface unit writes sector status data indicating the status of the sector, such as writing or completion of writing, to the sector management unit. Therefore, even if a power failure occurs at any point during writing, which sector data should be used as the latest data after the power failure recovery,
The interface can be easily identified.

When the power supply is stopped due to a power failure or the like, the power failure detection unit 15 detects the stop of the power supply and outputs a detection signal to the application unit 16. When a detection signal is input from the power failure detection unit 15, the application unit 16 outputs instruction data to which an emergency code indicating emergency writing is added to the interface unit 17, and sends the instruction data to the interface unit 17 so as to save predetermined state data. Make a write request. In step 53, when the interface unit 17 receives the instruction data with the emergency code added from the application unit 16, it selects an unused sector for emergency writing (step 63) and stores predetermined state data in this sector. Write (step 64). After the power is restored, once the interface unit 17 once reads data from the emergency write sector, the interface unit 17 erases the data in the emergency write sector and sets this sector to an unused state. Sometimes data can always be written to unused sectors. Therefore, it is possible to prevent a situation in which data cannot be saved due to a time delay due to garbage collection without the occurrence of empty blocks in the sector in an emergency and no garbage collection.

In this embodiment, the control system of the present invention is applied to a lighting control device. However, it goes without saying that the control system may be applied to a control device other than lighting, such as air conditioning and power.

[0053]

As described above, according to the first aspect of the present invention, there is provided an electrically rewritable flash memory in which a memory space is divided into a plurality of storage erasure units, and data is erased for each storage erasure unit; An interface unit for writing and reading data to and from a memory, and storing first write state information indicating a write state of data for each storage erase unit
Is provided in the flash memory, and when writing data to any one of the storage erasure units, if there is no free space in the storage erasure unit, the interface unit stores the valid data in the storage erasure unit. Is copied to another unused storage erasure unit, and at the same time, the data write start time, write completion time, and copy destination
When the data in the erase unit becomes valid, the copy source
At the time when the data in the erase unit is used,
Since the write state information of the first write state storage area is updated, the interface unit performs the corresponding storage erase from the write state information written in the first write state storage area. The current write state of the unit can be grasped.
Therefore, even if a power failure occurs at any time during writing, it is possible to easily determine whether or not the data of the storage erase unit is valid from the write state information.

According to a second aspect of the present invention, there is provided a second write state storage for storing a plurality of storage units into which data is written and write state information indicating a write state of data for each storage unit in a storage erase unit. And the interface unit updates the write state information of the second write state storage area when the write state of the data for each storage unit changes. From the write state information written in the write state storage area, the write state of data to each storage unit can be grasped. Therefore, even if a power failure occurs at any time during writing, it is possible to easily determine which of the old data before writing and the newly written data is valid.

According to a third aspect of the present invention, an interface unit is provided with an application unit for outputting instruction data for instructing data writing and reading, and when the instruction data from the application unit includes an emergency code indicating an emergency, The unit writes data in an unused emergency write storage erase unit different from the memory erase unit normally written. When evacuating data in an emergency,
If there is no free space in the memory erasure unit and garbage collection is performed, data may not be written in time.However, data is saved in an unused emergency write memory erasure unit. This has the effect of preventing a situation in which the user cannot make it in time.

According to a fourth aspect of the present invention, a counter area for storing the number of times of use of the storage erasure unit is provided for each storage erasure unit,
Each time data in the storage erasure unit is erased, the number of times of use stored in the counter area is counted up and written to the counter area. The number of uses of the erase unit can be grasped, and the life of the memory can be extended by using the memory erase unit equally.

According to a fifth aspect of the present invention, an initialized code area for storing an initialized code indicating whether or not the flash memory has been initialized is provided in the flash memory, and the interface unit is provided when the flash memory is initialized. Since the initialized code is written in the initialized code area at the time of erasing the data of the memory erasing unit, the interface unit
It is possible to know whether or not the flash memory has been initialized from the initialized code written in the initialized code area, and it is possible to prevent the failure of writing data to the flash memory.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a control system according to an embodiment.

FIG. 2 is a diagram showing a memory map of the flash memory according to the first embodiment;

FIGS. 3A to 3I are diagrams for explaining data written to a flash memory according to the first embodiment;

FIG. 4 is a flowchart showing the operation of the above.

FIG. 5 is a flowchart showing a data write operation of the above.

FIG. 6 is a diagram for explaining a process of changing block state data at the time of writing data in the embodiment.

FIG. 7 is a flowchart showing an operation when garbage collection is performed.

FIG. 8 is a diagram illustrating a process of changing sector state data when performing garbage collection according to the first embodiment.

FIGS. 9A to 9D are diagrams illustrating an operation when performing garbage collection in a conventional control system.

[Explanation of symbols]

 Reference Signs List 10 lighting control device 11 setting device 14 transmission processing unit 16 application unit 17 interface unit 18 flash memory

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G06F 12/16 310 G11C 16/02

Claims (5)

(57) [Claims] 1. An electrically rewritable flash memory in which a memory space is divided into a plurality of storage erasure units and data is erased in each storage erasure unit, and an interface unit for writing and reading data to and from the flash memory. A first write state storage area for storing write state information indicating a data write state for each storage erase unit is provided in the flash memory, and the interface unit stores the data in one of the storage erase units. If there is no free space in the storage erasure unit when writing, only valid data in the storage erasure unit is copied to another unused storage erasure unit,
At the start of writing data and at the end of writing data for each storage erasure unit
When validating the data of the memory erase unit of the point and the copy destination
The data of the memory erase unit of the
At a certain point in time, the control system updates the write state information in the first write state storage area. A plurality of storage units to which data is written, and a second write state storage area for storing write state information indicating a write state of data for each storage unit; 2. The control system according to claim 1, wherein the interface unit updates the write state information of the second write state storage area when the data write state of each storage unit changes. 3. An interface unit comprising: an application unit for outputting instruction data for instructing writing and reading of data; and when the instruction data from the application unit includes an emergency code indicating an emergency, the interface unit writes in an ordinary time. 3. The control system according to claim 1, wherein data is written in an unused emergency write storage erase unit different from the storage erase unit. 4. A counter area for storing the number of times of use of the memory erasure unit is provided for each memory erasure unit, and the number of times of use stored in the counter area is counted up every time data of the memory erasure unit is erased. 4. The control system according to claim 1, wherein the data is written in a counter area. 5. An initialized code area for storing an initialized code indicating whether or not the flash memory has been initialized is provided in the flash memory. 5. The control system according to claim 1, wherein when the data is erased, the initialized code is written to the initialized code area.