JP3600008B2 - Recording / reproducing device for batch erase type memory - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a recording / reproducing apparatus of a collective erasing memory that records and reproduces information using a collective erasing memory such as a flash memory.
[0002]
[Prior art]
In recent years, as information devices have been downsized, large-capacity semiconductor memories have been attracting attention as information recording media. In a semiconductor memory, as represented by a flash memory, information is written in a direction in which charge is extracted from a state where charge is injected into a cell for recording information in a bit unit, and the charge is injected into a plurality of bits, for example, A collective erasure type memory composed of 64 K bits or the like performed in units of blocks does not require a power supply for storing recorded contents and can be increased in capacity, so that it is widely used as a recording medium for information equipment. Is coming. The batch erasing type memory is used not only as being directly mounted in an information device but also as an information recording medium such as a memory card which is removable from the information device.
[0003]
Information devices to which a batch erasure type semiconductor memory is applied as an information recording medium are, for example, a personal computer, a digital camera, a voice recording / reproducing device, an electronic organizer, and the like. The information equipment system manages it using some means. Auxiliary information such as a flag is frequently changed with respect to main information having an attribute indicated by the auxiliary information. For this reason, even when the main information is recorded in the batch erasure type memory, a method of storing the auxiliary information in another type of semiconductor memory, for example, a static random access memory (SRAM) is generally used. ing.
[0004]
Most of the auxiliary information has a basic unit of a byte which is a processing unit of information, and one to several bytes constitute one information unit due to a system configuration, and recording and reproduction, transmission and reception are performed. I have. At the time of these processes, a synchronization signal, a correction signal, or the like is added to the main information signal constituting the minimum information unit, or a process such as interleaving is performed. The processing of recording, reproduction, transmission, and reception is performed as a signal of a plurality of bytes. For this reason, it is basically impossible to decompose an information unit and perform recording or reproduction, transmission or reception in units of one bit. Therefore, also on the information recording medium, the main information is basically recorded in an information unit of 1 byte to several bytes, and the auxiliary information indicating the attribute of the main information is naturally also in the unit of 1 byte to several bytes similarly to the main information. Is recorded in units of information. Since an information unit is composed of a plurality of bits, a temporary buffer for writing is generally used when writing information to a recording medium for transmission speed reasons. Further, the auxiliary information needs to be rewritten when there is a change in the attribute even if the content of the main information is not changed, and thus the auxiliary information is rewritten more frequently than the main information.
[0005]
[Problems to be solved by the invention]
In the collective erasure type memory, a cell in which data is recorded in bit units can only perform storage by rewriting from the recording state of one logical value corresponding to the erased state to the recording state of the other logical value. In order to rewrite the recording state of the other logical value to the recording state of one logical value, the entire block to which the bit belongs is erased once, and the entire block is changed to a state where one logical value is recorded. A batch erase that changes must be performed. Therefore, in order to record and manage the auxiliary information in the batch erasing memory, even if it is only necessary to rewrite one byte or one bit of information in one byte, the entire block including the information bit must be rewritten. In addition, rewriting takes a lot of time and inconvenience becomes a problem.
[0006]
As described above, due to the characteristics of the batch erasing memory, bits that have been written once cannot be overwritten unless the entire block is erased, and it is necessary to frequently rewrite information. For information management, there is a problem that the usability is poor and the number of times of rewriting increases. At the time of rewriting the entire block, the recorded content that does not need to be changed must be temporarily stored in another memory, and the stored content must be written again after erasing the block. Rewriting takes time. If the power is turned off during the rewriting, there is a problem that correct auxiliary information cannot be recorded. Further, in the batch erasure type memory, it is said that if the number of times of rewriting increases, there is a problem in data reliability, and if the number of times of rewriting increases, the life of the batch erasing type memory is shortened. Further, the erasing operation of the entire block consumes a large amount of power, and the more the number of times of rewriting, the more the power consumption. In particular, in a portable information device that operates on a battery, the duration of the battery is shortened.
[0007]
When the auxiliary information is recorded using a semiconductor memory of a type different from the batch erasing memory, the number of elements of the semiconductor memory that must be mounted increases, and many peripheral control circuits are required. If the semiconductor memory for recording the auxiliary information is a static random access memory, a power supply is required for holding the recorded contents. Mounting other semiconductor elements, batteries, and the like makes it difficult to miniaturize information devices, memory cards, and the like, and increases the manufacturing cost.
[0008]
An object of the present invention is to provide a recording / reproducing apparatus for a batch erasure type memory, which can record and reproduce main information and auxiliary information which needs to be rewritten more frequently than the main information. That is.
[0009]
[Means for Solving the Problems]
According to the present invention, a recording unit hierarchy is provided in the order of a bit which is a minimum recording unit, a byte which is an integral multiple of a bit, and a block which is an integral multiple of a byte, and information can be recorded from an erased state. In the recording / reproducing device of the batch erasure type memory as a unit,
The information to be recorded is divided into main information indicating the content of the information itself and auxiliary information indicating a predetermined attribute of the main information with a smaller number of bits than the main information. The main recording area for recording information and the auxiliary informationFirstRecording / reproduction control means for providing an auxiliary recording area having a number of bits recordable a plurality of times and recording and reproducing the main information on the main recording area;
Auxiliary recording means for performing the change of the auxiliary information by recording the auxiliary information in an area other than the area where the auxiliary information is already recorded in the auxiliary recording area;
An auxiliary reproduction unit that reproduces the auxiliary information based on the latest recorded content in the auxiliary recording area,
Recording and playbackcontrolThe auxiliary recording area provided by the means,
An integer multiple of the number of bits constituting the byte, and the number of bits required for the auxiliary information to indicate a change in the attribute of the main information for one cycle.SecondThe attribute indicated by the auxiliary recording area immediately after erasing,SecondAfter the attribute change for a plurality of cycles, all the bits of the auxiliary recording area are used to indicate the same attribute,
A recording / reproducing apparatus for a batch erasing memory, wherein the main recording area is for recording main information having an attribute indicated by auxiliary information to be recorded, and is provided in the same block.
[0010]
According to the present invention, a main recording area and an auxiliary recording area are provided by the recording / reproduction control means so that auxiliary information indicating an attribute of the main information can be recorded together with the main information in the batch erasing memory. The auxiliary recording area contains auxiliary information.FirstThe auxiliary recording means has a number of bits that can be recorded a plurality of times, and the auxiliary recording meansFirstCan be recorded multiple times. The auxiliary reproducing unit reproduces auxiliary information based on the latest recorded contents in the auxiliary recording area. In advanceFirstIf a method of reproducing the recorded content when a plurality of auxiliary information are recorded in the auxiliary recording area is defined, the auxiliary recording area is not used until the auxiliary information is recorded using all the one auxiliary recording area. It is not necessary to erase and rewrite the entire block to which it belongs, and the recorded content based on the additional rewriting of only the auxiliary recording area can be reproduced as auxiliary information. As a result, the number of times of rewriting as a whole block can be reduced, and the block rewriting life of the collectively erased memory can be extended. In addition, since erasure is not required for each rewrite, the time required for rewriting the auxiliary information can be shortened. The auxiliary information can be represented by the position and the number of bits having a logical value different from the erased state among the bits constituting the auxiliary recording area.
[0012]
The number of bits in the auxiliary recording area is one cycle for indicating the attribute of the main information, ie, 2 bits when the attribute is indicated by 1 bit, and 2 bits when the attribute is indicated by n bits.ⁿAll attributes of the main information can be represented by bits.Its secondSince the auxiliary recording area is set to be multiple times and to be an integral multiple of the byte that is the unit for information recording, the auxiliary informationSecondWhen recording is performed for a plurality of cycles, additional recording of auxiliary information can be performed by effectively using the auxiliary recording area.SecondEven after an attribute change for a plurality of cycles, since the same attribute as the attribute indicated by the multi-function recording area immediately after erasure is shown, it can be used effectively. Since the number of bits in the auxiliary recording area is an integral multiple of the number of bytes, the recording of auxiliary information after block erasure can be quickly performed in byte units.
[0014]
In addition, since the auxiliary area and the main area are provided in the block of the batch erasing memory, the main information and the auxiliary information indicating the attribute thereof can be recorded in the same block. When the number of bits of the auxiliary information is small, it is not necessary to use one entire block for recording the auxiliary information, and the main information and the auxiliary information can be recorded by effectively using the recording area in the block. For example, recording of main information requires a plurality of blocks, and auxiliary information indicating the attribute of the main information can be recorded in only one of the plurality of blocks. Further, only the main recording area can be allocated to the main information that does not require the auxiliary information, and the recording capacity of the collectively erasing memory can be effectively utilized.
[0015]
Further, in the present invention, the auxiliary recording unit records the auxiliary information in the auxiliary recording area in a predetermined order with respect to an array of bits constituting the auxiliary recording area.
[0016]
According to the present invention, when the auxiliary information is recorded a plurality of times in the auxiliary recording area, a predetermined order for an array of bits constituting the auxiliary recording area, for example, from the LSB bit area corresponding to the lowest weight, The recording is performed sequentially toward the MSB bit area corresponding to the highest weight. As a result, it is possible to shorten the time when the auxiliary information is recorded by the auxiliary recording unit and the time when the auxiliary information is reproduced by the auxiliary reproducing unit, and reduce the load on the software for performing those processes. it can. That is, in the batch erasing type memory, additional writing cannot be performed on the bit once written, so that if the auxiliary information is randomly written in the auxiliary recording area, the writing of the next auxiliary recording information is not performed. At this time, it is necessary to search for an area in which writing has not yet been performed and write auxiliary information in the searched area, and the operation of the searching means and control means for this and the time required for searching need to be performed. Although necessary, by performing recording in a certain order, these times can be reduced, and the burden on hardware and software can be reduced.
[0017]
The present invention also provides a temporary memory for temporary storage,
The auxiliary recording unit includes the auxiliary recording unit in the auxiliary recording area.FirstWhen recording the auxiliary information more than once, the recorded content of the block having the auxiliary recording area is stored in the temporary memory, and after the recorded content of the block is erased, the stored content of the temporary memory is deleted. It is characterized by recording in blocks.
[0018]
According to the present invention, the auxiliary recording area is provided by the auxiliary recording means.FirstIt is possible to record auxiliary information a plurality of times. If the number of times of recording of the auxiliary information exceeds the plurality of times, the auxiliary recording unit saves the recording content of the block having the auxiliary recording area in a temporary memory for temporary storage when recording the next auxiliary information, and Since the recorded contents of the temporary memory are recorded in the block after erasing the recorded contents of the block, recording exceeding the plurality of times in the auxiliary recording area without affecting other information in the same block as the auxiliary recording area is performed. It can be performed. Since other blocks of the batch erasure type memory are not used for temporarily storing other information of the block, it is possible to prevent the life of the block from being shortened by rewriting.
In the present invention, the attribute indicates whether data can be written to or erased from the block.
According to the present invention, the attribute indicated by the auxiliary recording area can indicate whether writing or erasing to a block is possible.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows a schematic electrical configuration of a recording / reproducing apparatus for a batch erasure type memory according to an embodiment of the present invention. In the flash memory 1 which is a batch erasing memory, recording and reproduction are controlled by the control circuit 2. The control circuit 2 includes a microcomputer, and also includes a ROM for storing a program for operating the microcomputer. The key input means 3 is used to input a read / write command, a read / write prohibition command, and the like, and its output is given to the control circuit 2. The data input / output means 4 is provided for inputting / outputting data for recording and reproducing information in the flash memory 1, and is connected to the control circuit 2. As the data, for example, data such as music is handled. The protection switching means 5 is capable of switching between protection and non-protection for the entire memory of the flash memory 1, for each block, or for a storage unit such as a song for music. The protection switching means 5 may be provided in the flash memory 1, or may be independently provided outside the flash memory 1 as protection switching means 5 'indicated by a virtual line. The control circuit 2 can also cause the display means 6 to display the input contents from the key input means 3 and the protection switching means 5 and 5 '. The display means 6 is composed of, for example, a liquid crystal display (LCD). The control circuit 2 has a built-in memory 23 used for temporary buffering of data.
[0020]
The flash memory 1 is composed of a chip group 1 ′ composed of n flash memory chips 7, 8, 9,..., And the above-described protection switching means 5. It is used as a recording medium that is removable from the device.
[0021]
FIG. 2 shows a configuration of a main part as one semiconductor memory chip of each of the flash memory chips 7, 8, 9,. Each flash memory chip 7, 8, 9,... Includes m blocks 11, 12, 13,. The blocks 11, 12, 13,... Of each batch erasing unit are data areas 15, 16, 17,... Which are main recording areas for recording main information, and flag areas 19, 20 which are auxiliary recording areas for recording auxiliary information. , 21,... Respectively. All blocks that do not use the flag area for recording the auxiliary information can be used as the main information data area. That is, a part of the data area is used as the flag area. Also, the byte setting addresses indicating the address positions in the memory space of the auxiliary information recording flag area need not necessarily be unified designated addresses, and there is no need to set restrictions on the address setting.
[0022]
Next, the data format of the main information and the sub auxiliary information will be described. The data handling unit at the time of transmission / reception by the data input / output means 4 of FIG. 1, the data handling unit at the time of data processing at the control circuit 2, and the data processing unit at the time of transmission / reception to the flash memory 1 are main information and Both auxiliary information is processed in units of bytes. If the auxiliary information is, for example, a one-bit flag indicating permission and prohibition of recording and reproduction of the main information, an attribute of one cycle can be represented by two bits, and eight bits, which is four times as large as one cycle, can be represented by one. Treat as a byte. When the attribute of the main information is represented by two bits, one cycle requires four bits, and eight bits can indicate the attribute for two cycles. When the number of bits of the auxiliary information indicating the attribute increases, the number of bits of one byte is increased. Further, depending on the processing speed and the processing form of the control circuit 2, one byte can be composed of 16 bits, 32 bits, or even 64 bits. Although the minimum unit for recording to the flash memory 1 is a bit, it is generally recorded in a byte unit. The minimum unit at the time of erasing is a block unit.
[0023]
FIG. 3 shows a procedure for collectively erasing blocks in the flash memory 1. The procedure starts from step a1, and in step a2, all the charges in the cells in the block to be erased in batch are removed. In a cell for recording one bit, a logic value "1" is shown when charge is injected, and a logic value "0" is shown when charge is removed. Then, each bit becomes “0000000000”. Next, in step a3, erase is performed by injecting charges into all the bits in the block. As a result, in the byte within the erased block, the bit data becomes “11111111”, and the erase ends at step a4. Some types of flash memories require that charge injection and extraction be performed in reverse. In such a type, the handling of charges is reversed from that described above.
[0024]
Recording of data in the flash memory 1 is performed by removing charges from cells corresponding to “0” bits of recording data. That is, when data "11111100" is to be recorded, it is only necessary to remove the 2-bit charge on the LSB side. Then, when the byte is rewritten to the data “11111101”, the data “0” of the bit on the LSB side may be rewritten to “1”. However, in the flash memory 1, charges are injected only to a specific bit. I can't. Therefore, as shown in FIG. 3, after the data of all the bits in the block including the byte is collectively erased, the charge of only the second bit is extracted from the LSB side of the byte, thereby obtaining the data “11111101”. Rewriting is finally completed. At this time, in the block to be collectively erased, data that is not to be rewritten needs to be temporarily recorded in another part before the collective erasure, and to be recorded with the original contents after the collective erasure. In the current flash memory 1, reduction of the area required as a semiconductor chip and reduction of power consumption are prioritized over convenience of enabling erasing in byte units.
[0025]
In the recording / reproducing apparatus of FIG. 1, for example, when music information is input from the data input / output unit 4 and recording is designated by the key input unit 3, a recording command is input to the control circuit 2. The control circuit 2 confirms that the protection switching means 5, the key input means 3 or the dedicated protection switching means 5 'provided in the flash memory 1 is set to be recordable, and determines that the recording mode is set. It is displayed on the display means 6. The music signal data byte as the main information and the flag byte as the auxiliary information are both sent to the chip group 1 ′ of the flash memory 1. The transmitted music signal data bytes as main information and the flag bytes as auxiliary information are input to the chip group 1 'of the flash memory 1 and recorded in byte units.
[0026]
When the control circuit 2 confirms that the recording is prohibited by referring to the protection switching means 5, the key input means 3 or the external dedicated protection switching means 5 ', each data is recorded in the flash memory 1. Without the recording, the reason why the recording cannot be performed is displayed on the display unit 6.
[0027]
Next, when reproduction is input from the key input means 3, a reproduction command is input to the control circuit 2. The control circuit 2 confirms that the protection switching means 5, the key input means 3 or the external dedicated protection switching means 5 'in the flash memory 1 is set to reproduction permission, and indicates that the reproduction mode is set. To display. The control means 2 calls the recorded data from the designated address of the chip group 1 'of the flash memory 1 and outputs the data from the data input / output means 4 to the outside.
[0028]
FIG. 4 shows a processing procedure in one flash memory chip 7, 8, 9,... In the flash memory chip group 1 '. As shown in FIG. 2, the flash memory chips 7, 8, 9,... Have a data area composed of a plurality of bytes in which main information is recorded and a flag area composed of one byte in which auxiliary information is recorded. .. Having a plurality of batch erase blocks 11, 12, 13,. In step b1, an erase operation is performed in block units as shown in FIG. When the erasing operation in units of blocks is executed, all the bytes existing in the block are initialized to “11111111”. Each bit of one byte of the flag area is initialized similarly. This state is set to a writable state as shown in step b2. Next, in step b3, it is determined whether or not there is an input from the key input means 3 for prohibiting the writing of the flag byte information as auxiliary information. If there is an input for prohibiting the writing of the information of the flag byte, the LSB bit of the flag byte is reduced to “0” in step b4, and is set to “11111110”. Next, in step b5, the process waits for an input from the key input means 3 to enable writing of the flag byte of the auxiliary information. If there is an input indicating that writing is possible, the flag byte is updated in step b6 so as to be in a writing enabled state. That is, when the auxiliary information is updated, the state of the flag byte may be changed, and the second bit is dropped from the LSB side to be “11111100”.
[0029]
In step b7, it is determined whether or not the entire one-byte flag byte has been updated. As described above, when the bits from the LSB side to the second bit have been updated, there is room for recording data for an additional 6 bits, and the process returns to step b3. When an input for inhibiting the flag byte information of the auxiliary information from being written is performed from the key input means 3 in step b3, an update is performed in step b4 such that the flag byte of the auxiliary information is set in the write-inhibited state. As a result, the flag byte becomes “11111000”. As described above, even if the block to which the flag byte belongs is not collectively erased, it is possible to update the auxiliary information only by dropping the bit using the characteristics of the flash memory 1.
[0030]
As described above, when the flag byte of the auxiliary information is updated according to the input from the key input unit 3, the state of the last flag byte becomes “00000000”. In this case, since there is no more bit to be dropped to "0", the update cannot be performed by the above-described method. In this case, the process moves from step b7 to step b8, and the flag byte automatically belongs to the flag byte. A block erase operation is performed to return the flag byte to the initial state “11111111”.
[0031]
However, in block erasure, each byte of the main information data area recorded in the main recording area other than the flag byte is also initialized to “11111111”. Therefore, if it is difficult to initialize the entire erase block, the memory 23 in the control circuit 2 is used to temporarily store the recording data in the block at step b8. Thereafter, in step b9, the blocks as shown in FIG. 3 are erased collectively, and in step b10, the blocks having the storage contents temporarily stored in the memory 23 are re-recorded, and the process returns to step b2.
[0032]
If a block is set to be writable, and if the system configuration is such that all the main information of the block is erased, there is no need to perform the processing of steps b8 and b10, and only the block erasing of step b9 is performed. For example, it can be automatically initialized. Also, the order of recording for each bit may be determined not in the order from the LSB side to the MSB side but in the opposite direction or in another order.
[0033]
What is important here is that one byte is 8 bits, and the auxiliary information is a repetition of “erasable” and “erase prohibited”. That is, the number of bits to be executed is four times the number of bits per cycle, that is, an integral multiple. As a result, the attribute of the main information indicated by the auxiliary information does not change at all when all the bits of one byte are rewritten, even if the data is erased and initialized one byte at a time. . Even if one byte is composed of eight bits, if the number of bits for one cycle of the auxiliary information is, for example, three bits, the initialization will affect the state before the initialization, and the attribute indicated by the auxiliary information will be affected. The content changes. When the number of bits for one cycle of the auxiliary information is three, for example, one byte needs to be 12 bits. However, it is preferable that one byte is an integral multiple of 8 bits because of a data bus width of a microcomputer or the like constituting the control circuit 2, and the size of the flag area for recording the auxiliary information is 8 bits × 3 = The size of the auxiliary recording area may be treated as 3 bytes, with 24 bits being 1 byte or 1 byte being 8 bits.
[0034]
That is, assuming that the initial value of the flag byte as the auxiliary information is “11111111”, if the state immediately after the initialization is previously defined as the erasure prohibited state, the flag byte of the auxiliary information is changed from the erasing permission “11111110” to the erasing prohibited “11111100”. , The erasure permission “11111000” can be sequentially updated. Eventually, the flag byte of the auxiliary information becomes “00000000”, which is the same as the initial value, meaning that erasure is prohibited. The auxiliary reproducing means for reproducing the flag byte at this time may determine whether the number of bits "1" is even or odd and indicates whether erasure is prohibited or erasure permitted.
[0035]
If the initial value of the flag byte of the auxiliary information is set to “11111111” and the state immediately after the initialization is defined in advance as a state in which erasure is permitted, contrary to the above description, the flag byte of the auxiliary information is set to “11111110”. Can be sequentially updated to erase permission “11111100” and erase inhibition “11111000”. Eventually, the flag byte of the auxiliary information becomes “00000000”, which means that erasure is permitted. That is, setting the flag byte of the auxiliary information to “00000000” means that the block including the flag byte is collectively erased by inputting this area to the key input means 3. When the erasure is completed, the data area for recording the main information and the flag area for recording the auxiliary information in the block are initialized, and all the bytes in the block become "11111111" again. Then, the flag byte becomes the same as the initial state, and indicates the erasure permission. The block that has been subjected to batch erasure is in an initial state in both the data area for recording main information and the flag area for recording auxiliary information, and can be used without changing the auxiliary information when next used.
[0036]
However, when the erasure prohibition is performed by changing only the auxiliary information from the state where the flag byte of the auxiliary information is “00000000”, the erasure prohibition is input from the key input means 3, and the flag byte of the auxiliary information already has all the bits. Since it is "0", no further rewriting can be performed. When the block including the flag byte is initialized collectively and the auxiliary information is rewritten, the main information is also initialized. Remember temporarily. After block erasure, the main information data of all data temporarily stored in the memory 23 in the control circuit 2 is re-recorded in the data area of the block. Since the flag byte of the auxiliary information is "11111111" indicating erasure permission, the LSB side bit is dropped to "11111110" to prohibit erasure. This makes it possible to prohibit erasure while maintaining the data for recording main information.
[0037]
Further, although the above description is directed to a batch erase type semiconductor memory, the present invention can be applied to other batch erase type information recording media such as a write-once optical disc.
[0038]
【The invention's effect】
As described above, according to the present invention, for the auxiliary information indicating the attribute of the main information, the block erasure is not performed in the batch erasure type memory.FirstMultiple recordings can be made. Generally, the auxiliary information can be updated promptly without the time-consuming batch erasing operation, so that the operation waiting time can be greatly reduced. In addition, since the auxiliary information can be updated quickly, it is possible to reduce the possibility of occurrence of an accident such as a power-off during the update of the auxiliary information. In addition, since the life of a batch erase type semiconductor memory generally becomes shorter as the number of batch erases increases, the life can be extended by greatly reducing the number of batch erases. In addition, since power consumption increases at the time of batch erasure, by reducing the number of times of batch erasure in portable information devices and the like, power consumption can be reduced and the life of a power supply battery can be extended. .
[0039]
Further, the number of bits of the auxiliary recording area is an integral multiple of the number of bits required to indicate a change in the attribute of the main information by one cycle by the auxiliary information, so that the attribute of the main information can be easily managed cyclically. It becomes. If the auxiliary information is set so that the initial state of the auxiliary information is displayed after the batch erasure, it is possible to eliminate the waste of initializing the auxiliary recording area after batch erasing the entire block including the auxiliary recording area. it can.
[0040]
Further, the auxiliary recording area for recording the auxiliary information is provided in the same block as the main recording area for recording the main information having the attribute indicated by the auxiliary information, so that one block is provided in the main recording area and the main recording area. It consists of an auxiliary recording area for recording auxiliary information indicating the attribute of the main information to be recorded, or consists only of the main recording area. Therefore, the auxiliary information can be set in a part of the block without providing an auxiliary recording area for recording the auxiliary information indicating the attribute of the main information separately from the block to which the main recording area belongs. . As a result, restrictions on block setting when using the batch erasing memory are reduced, and the degree of freedom can be increased. Further, the number of bits in the auxiliary recording area is less restricted, and the recording area in the block can be effectively used.
[0041]
According to the present invention, the recording order of auxiliary information in the auxiliary recording area is sequentially recorded from the LSB side to the MSB side in accordance with the bit arrangement, thereby shortening the time required for recording and reproduction, and reducing hardware and software. Can be reduced.
[0042]
According to the present invention, the number of times of recording the auxiliary information in the auxiliary recording area can be recorded.FirstWhen the number of times exceeds a plurality of times, the recording contents of the block to which the auxiliary recording area belongs are temporarily stored in the temporary memory, so that the auxiliary information can be recorded with minimum necessary rewriting without rewriting other blocks of the batch erasure type memory. It can be performed.
Further, according to the present invention, it is possible to effectively indicate whether or not a block can be written or erased.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic electrical configuration of an embodiment of the present invention.
FIG. 2 is a block diagram showing an internal configuration of the flash memory chips 7, 8, 9,.
FIG. 3 is a flowchart showing a procedure in which a control circuit 2 in FIG. 1 performs block erasure of a flash memory 1;
4 is a flowchart showing a recording procedure of auxiliary information in each of the flash memory chips 7, 8, 9,... Of FIG.
[Explanation of symbols]
1 Flash memory
1 'chip group
2 Control circuit
3 Key input means
4 Data input / output means
5,5 'protection switching means
6 Display means
7, 8, 9, ... Flash memory chip
11, 12, 13, ... block
15, 16, 17, ... data area
19, 20, 21, ... Flag area
23 memory

Claims (4)

A recording unit hierarchy is provided in the order of a bit which is the minimum recording unit, a byte which is an integral multiple of a bit, and a block which is an integral multiple of a byte, and information can be recorded from the erased state. In an erasable memory recording / reproducing device,
The information to be recorded is divided into main information indicating the content of the information itself and auxiliary information indicating a predetermined attribute of the main information with a smaller number of bits than the main information. A main recording area for recording information and an auxiliary recording area having a first plurality of recordable bits for the auxiliary information are provided, and recording and reproduction of the main information are performed on the main recording area. Recording and reproduction control means;
Auxiliary recording means for performing the change of the auxiliary information by recording the auxiliary information in an area other than the area where the auxiliary information is already recorded in the auxiliary recording area;
An auxiliary reproduction unit that reproduces the auxiliary information based on the latest recorded content in the auxiliary recording area,
The auxiliary recording area provided by the recording / reproduction control means,
The number of bits is an integral multiple of the number of bits constituting the byte, and the auxiliary information is composed of a second multiple of the number of bits required to indicate a change in the attribute of the main information for one cycle, and is erased. and attribute indicated by the auxiliary recording area immediately after, after a change of the second plurality of cycles minutes attributes are identical to the attributes shown in all the bits are used for auxiliary recording area,
A recording / reproducing apparatus for a batch erasing memory, wherein the main recording area is for recording main information having an attribute indicated by auxiliary information to be recorded, and is provided in the same block. 2. The batch erasure according to claim 1, wherein said auxiliary recording means records said auxiliary information in said auxiliary recording area in a predetermined sequence with respect to an array of bits constituting said auxiliary recording area. Recording / reproducing device for die memory. Provide temporary memory for temporary storage,
When the auxiliary information is recorded in the auxiliary recording area more than the first plurality of times, the auxiliary recording unit stores the recording content of the block having the auxiliary recording area in the temporary memory, and 3. The recording / reproducing apparatus according to claim 1, wherein the contents stored in said temporary memory are recorded in said block after erasing the recorded contents. 4. The recording / reproducing apparatus according to claim 1, wherein the attribute indicates whether data can be written to or erased from the block.

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