JPH09128302A - Data access method to non-volatile memory - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently make data-access to a non-volatile memory by adding an external memory to the non-volatile memory of a package loading CPU in a transmission device system. SOLUTION: The device used for the method is provided with a non-volatile memory 1 for storing data, a CPU 7 accessing data on the non-volatile memory 1, a PKG 9 loading CUP, which has data of the same structure/same value as the non-volatile memory 1 and has RAM data 2 which can always be read/ written from/into CPU, an external by added memory 3 which has the same structure at the non-volatile memory 1 and which exists on a PKG different from the PKG loading CPU, a virtual space 4 addressing the external by added memory 3 on the same memory of RAM data 2 and the plural non-volatile memories 2 for the backup of the non-volatile memory 1. A FILE control function 6 controls/manages the PKG loading CPU 9 and a PKG loading external by added memory 10 with such constitution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data access method for a non-volatile memory of a CPU mounted package in a transmission device system. Particularly, the present invention relates to performance improvement / quality improvement / reliability improvement / control efficiency improvement in a device using a non-volatile memory.

In recent years, with the demand for data management in high-speed and multi-functional computer systems, an increasing number of devices are equipped with a non-volatile memory capable of maintaining data even after the device is stopped. The mounted non-volatile memory is often used for changing or storing data such as the setting conditions of the device and the energization time, or for the purpose of storing backup data.

[0003]

2. Description of the Related Art The use of non-volatile memories has been accompanied by some functional restrictions. FIG. 8 shows a connection configuration example and a processing flow of a conventional CPU-installed PKG. In the figure, 21
Is non-volatile memory, 22 is memory, 23 is CPU, 24 is CP
U-installed PKG, 25 is RAM data, and 26 is a FILE control function.

The CPU-equipped PKG 24 has a non-volatile memory 21 for storing data, a CPU 23 for accessing data on the non-volatile memory, and data having the same structure / value as the non-volatile memory, and always reads / writes from the CPU. It has RAM data 25 that can
It has an E control function 26, and accepts requests from requesters and controls data settings.

The process flow is as follows: (21) When a write request is received from the request source, writing is started in the non-volatile memory, (22) Wait for the write timing, and (23) Check whether or not the write is completed. If the writing is not completed yet, the writing timing is waited again. When the writing is completed within the writing timing, the writing from the request source to the nonvolatile memory is completed.

FIG. 9 shows a conventional write / read request sequence diagram. The figure shows a case where a request for reading is issued from the request source 2 during a write request from the request source 1. In the FILE control function, the time set by the timer is set between the write request to the nonvolatile memory and the write confirmation.
Even if there is a request to read data from another requester 2 during this time, the data cannot be read until the requester 1 completes writing,
It becomes possible to read after writing is completed.

As shown in FIG. 9, since a nonvolatile memory requires a certain writing time when writing data, it takes a considerable time to include the determination of the writing processing result. Furthermore, the new read and write requests received during this fixed write time cannot be processed until the result of the write process being executed is confirmed. For this reason, this becomes a constraint on the software and is a major cause of delaying the system response time.

Further, the nonvolatile memory has a limit on the number of times of writing in advance. There are many functions that notify this in some form when the maximum write count is reached, but the memory content that exceeds the maximum write count has a low degree of guarantee of data content. Further, in this case, a replacement procedure is required, and data migration at that time becomes a problem.

[0009]

As described above, the non-volatile memory has the drawbacks that "the processing time at the time of writing is long" and "the number of writable times is limited."
The application software is greatly affected by these factors.

An object of the present invention is to reduce the influence of application software by managing a combination of a non-volatile memory and a volatile memory (RAM).

[0011]

FIG. 1 is a block diagram showing the principle of the present invention. In the figure, 1 is a non-volatile memory, 2 is RA
M data, 3 external memory, 4 virtual space, 5 non-volatile memory for backup, 6 FILE control function, 7
Is a CPU, 8 is a memory, 9 is a PKG equipped with a CPU, and 10 is P
Indicates KG.

The non-volatile memory 1 is an E2PROM for storing data, the CPU 7 is a processing unit for accessing the data on the non-volatile memory, and the RAM data 2 has the same structure / value data as the non-volatile memory 1, RAM data that can always be read and written by the CPU, external memory 3
Indicates an external memory having the same configuration as the nonvolatile memory, having the latest data, and existing on the PKG 10 different from the CPU-installed PKG 9 described above.

In the virtual space 4, the external memory 3 is stored in the RA described above.
The virtual space addressed on the same memory 8 as the M data 2 and the backup non-volatile memory 5 are a plurality of non-volatile memories (E) for backup of the non-volatile memory 1.
2PROM) is shown. Control and management of the CPU-equipped PKG 9 and the external memory 3-equipped PKG 10 having these configurations are performed by the FILE control function 6 of the CPU 7.

FIG. 2 shows the principle of the present invention. The figure shows
The application program, the FILE control function, the virtual space, the external memory, and the RAM in the principle configuration diagram of FIG.
The sequence diagram between data, a non-volatile memory, and a non-volatile memory for backup is shown. When writing is set in the application program by the writing request from the request source, data is written to the FILE control function, data is written to the external memory via the virtual space, and data is written from the FILE control function. Is set in the application program. When read is set in the application program by the read request from the request source, the FILE control function is read, and data is read from the virtual space.
The data read result is set in the application program. When the next write request comes from the request source and write is set in the application program, the FI
Data is written to the LE control function, data is written to the external memory via the virtual space, and the result of data writing is set in the application program by the FILE control function. When copying from the external memory to the non-volatile memory is set by the timer 1 of the application program,
The FILE control function compares the data in the virtual space with the RAM data. Only when there is a difference in the comparison result, the copy processing is performed by the FILE control function, and the data written in the virtual space is written in the RAM data. , RAM data is written to the non-volatile memory. When priority write is set in the application program, data is written to the FILE control function and data is written to the external memory via the virtual space. The data written in the virtual space by the FILE control function is compared with the data written in the RAM data, and only when there is a difference, the FILE control function performs the copy process, writes in the virtual space, and writes the data from the virtual space to the RAM. The data is written and the non-volatile memory is written. When copying from the non-volatile memory to the backup non-volatile memory is set by the timer 2 of the application program, the copy processing is performed by the FILE control function, the non-volatile memory is written, and the non-volatile memory is used for backup. Writing is performed in the nonvolatile memory.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 shows a processing flowchart of the FILE control function of the present invention. In the figure, (1) Check whether there is an input factor from the application program. Input factors include a time condition and a write count condition, and the detection source is detected inside the FILE control or by the OS / timer control. (2) If the input factor is write acceptance, check whether it is immediate processing, (3) Check if it is not immediate processing and whether timer setting is in progress, or (4) if timer setting is not in progress, set timer The settings are made and the process ends. (5) If the timer is being set, priority timer processing is performed. (6) By the priority timer processing, it is checked whether or not a time-out is detected, and if the time-out is not detected, the processing ends. (7) If a time-out is detected, write to the non-volatile memory. If there is no input factor in the input factor check in the item (1), write to the non-volatile memory. Said
Even in the immediate processing check in item (2), if it is an immediate processing, the data is written to the non-volatile memory. (8) Wait for the write timing to the non-volatile memory, (9) Check if the write is completed, and repeat the write timing wait in (8) until the write is completed. (10) If the writing is completed, it is checked whether the number of times of writing is equal to the specified value, and if not, the processing is ended. (11) If the value is the specified value, an external notification process indicating that the specified value has been reached is performed.

Among the embodiments of the processing flow, (7), (8),
The processing of item (9) is related to the conventional processing flow, and the other processing flows are related to the present invention. Examples of the present invention will be described below. The composite request sequence diagram of the present invention is shown in FIG. The figure shows a case where a new write / read request is received during the writing process to the non-volatile memory. In the conventional case, the new request waits until the confirmation of the write result is completed. Immediate response after writing to memory. F that independently performs copy processing between external memory and non-volatile memory
The ILE control function enables simultaneous processing of new requests.

In the composite request sequence diagram of FIG. 4, when the write request from the request source 1 is accepted by the request acceptance of the FILE control function, the data is written in the RAM data and the data is written in the external memory from the RAM data. The FILE control function notifies the requester 1 of the data writing result.

A request for processing is sent from the requester 2 by a timer to F
When the ILE control function is executed, the setting control unit compares the data written in the external memory with the data written in the non-volatile memory, and only when there is a difference in the data, the external memory The data is copied to, the data having the difference is set in the non-volatile memory, and the timer for confirming the writing is set.

A request for reading data from the request source 2 is FILE.
When the control function is executed, the data is read from the external memory even while the write data timer is set, and the FI
The read data of the LE control function is read by the request source 2. Therefore, the requester 1 can read the data being written in the nonvolatile memory from the requester 2 from the external memory. . A write sequence diagram of the present invention is shown in FIG. The figure shows that when a data write request is received, it is not a non-volatile memory
By writing in the virtual space, the processing speed can be improved, the response to the requester can be made faster, and the time constraint can be eliminated. Further, copying from the virtual space to the non-volatile memory is periodically performed using a timer or the like. Therefore, when there is a write request due to the same factor within the same period, the number of times of writing can be reduced.

In the write sequence diagram of FIG. 5, when the request source requests the FILE control function to write data, R
Data is written to the external memory via the AM data, and the processing result is notified to the requester. Then, when the requester makes a similar data write request to the FILE control function, the data is written to the external memory via the RAM data and the processing result is notified to the requester.

When the FILE control function is requested to process by the timer, the data written in the external memory and the data written in the non-volatile memory are compared, and there is a difference between both data. Only at this time, data is copied to the external memory by the FILE control function, and the copied data is set in the non-volatile memory. Therefore, the data is backed up in another area to cope with the failure in the external memory. . A priority write sequence diagram of the present invention is shown in FIG. In the writing sequence of FIG. 5 described above, copying from the virtual space to the non-volatile memory is based on only timer notification, but there are two exceptions. One of them depends on the priority level of the write request. By adding the priority level to the data write request received by the FILE control task, immediate copying can be performed without waiting for the timing of the above-mentioned timer.

In the priority write sequence diagram of FIG.
When the request source issues a data write request to the FILE control function, the data is written to the external memory via the RAM data, and the processing result is returned to the request source. When a priority level processing request is sent to the FILE control function, the data written in the external memory and the data in the non-volatile memory are compared, and when there is a difference, the data is copied to the external memory and the non-volatile Data is set in the local memory.

Similar to the pattern of FIG. 6, when the apparatus falls into a state where external control is impossible due to a system failure or maintenance work, immediate copying is performed without waiting for the timing of the above-mentioned timer. As a result, the latest data is reflected in the non-volatile memory. . FIG. 7 shows a connection configuration diagram of the backup non-volatile memory of the present invention. The data in the non-volatile memory is regularly
The backup is saved in a non-volatile memory for backup different from the non-volatile memory. The non-volatile memory for pack-up can reduce the number of times of writing as compared with the non-volatile memory and can cope with a chip failure or the like. Similarly, by saving the data and history in units of designated items to a non-volatile memory for backup, partial duplication adapted to the user's needs becomes possible.

Further, by making it possible to copy these non-volatile memories for pack-up to the non-volatile memory, the maintainability of the apparatus / storability of data is improved. . Next, when data is written to the non-volatile memory that exceeds the maximum number of writes, the contents are not guaranteed due to deterioration of the non-volatile memory, etc. / Quality may be affected. In order to avoid such a decrease, advance notice is given to the maintenance person or the like before the maximum number of times of writing is achieved.

As described above, as a result of reading the data in the non-volatile memory to the RAM data / virtual space when the system is started up, when the read or write processing request is made, the non-volatile memory is originally used. It is possible to replace a place that requires access to the virtual space with access processing to the virtual space. This method causes a data shift between the non-volatile memory and the external memory.
Since the control function is solely responsible, the performance of the application software can be improved sufficiently.

The FILE control function copies data from the virtual space to the non-volatile memory in order to eliminate the above-mentioned data shift. This is performed at each timing of each timer notification in order to reduce the number of writings to the nonvolatile memory. However, there are two exceptions. First, if the priority level of the data write request is high, such as when the write data is an important item or during processing with a high degree of urgency, this is determined and immediate copying is executed. The second is to execute the actual copying process when an external control disabled state occurs due to a system failure or maintenance work.

When the copying process is executed, the difference between the non-volatile memory and the latest data is checked by comparing the RAM data with the virtual space. As a result, the actual copying process is executed only when the difference is detected. The difference check can be performed by dividing the data, and the copying process in this case is performed only on the division in which the difference is detected.

When copying data, a function to save the data in the external memory to another area at any time is also possible in order to cope with a failure of the external memory when there is a difference between the external memory and the non-volatile memory. And Furthermore, in order to improve the data storage property in the non-volatile memory, the non-volatile memory is saved wholly / partially in the backup non-volatile memory. By providing the data copying function from the backup non-volatile memory to the non-volatile memory, efficiency can be improved when the operation mode of the device is changed or a specific environment is constructed, and maintainability is improved.

[0029]

As described above, according to the present invention, the system response is speeded up by hierarchical management of data, the quality is improved by reducing restrictions on application software,
It greatly contributes to the improvement of reliability during maintenance and the improvement of reliability by controlling the number of times of communication.

[Brief description of the drawings]

FIG. 1 is a diagram showing the principle configuration of the present invention.

FIG. 2 is a diagram illustrating the principle of the present invention.

FIG. 3 is a processing flowchart of a FILE control function of the present invention.

FIG. 4 is a composite request sequence diagram of the present invention.

FIG. 5 is a writing sequence diagram of the present invention.

FIG. 6 is a priority write sequence diagram of the present invention.

FIG. 7 is a connection configuration diagram of a backup non-volatile memory of the present invention.

FIG. 8 is a connection configuration example and processing flow of a conventional PKG equipped with a CPU.

FIG. 9 is a conventional write / read request sequence diagram.

[Explanation of symbols]

 1,21 Non-volatile memory 2,25 RAM data 3 External memory 4 Virtual space 5 Non-volatile memory for backup 6,26 FILE control function 7,23 CPU 8,22 Memory 9,24 CPU mounted PKG 10 PKG

Claims (5)

[Claims] 1. In a data access to a non-volatile memory of a CPU-equipped package in a transmission device system, a non-volatile memory for storing data, a CPU for accessing data on the non-volatile memory, and the non-volatile memory. A PKG equipped with a CPU having data of the same structure / equal value and RAM data that can always be read and written from the CPU, and the latest data with the same configuration as the nonvolatile memory, which is different from the above-mentioned PKG equipped with the CPU. An external memory existing in the above, and a virtual space obtained by addressing the external memory on the same memory as the RAM data described above,
A CPU-installed PK having a plurality of non-volatile memories for backup of the non-volatile memory and having these configurations
Control and management of G and PKG with external memory are performed by the FILE control function of CPU, and when a new write / read request is accepted during the write processing to the non-volatile memory, Immediate response after writing. A data access method to a non-volatile memory, characterized in that a new request is simultaneously processed by a FILE control function for independently performing a copying process between the external memory and the non-volatile memory. 2. When receiving a data write request to the non-volatile memory, the processing speed is improved by writing to the virtual space instead of the non-volatile memory, and copying from the virtual space to the non-volatile memory is performed. 2. The method for accessing data to the non-volatile memory according to claim 1, wherein the data access is performed by using a timer. 3. When receiving a data write request to the non-volatile memory, copying from the virtual space to the non-volatile memory is performed by F.
3. The method for accessing data to a non-volatile memory according to claim 2, wherein the priority level is added to the data write request received by the ILE control task so that immediate copying is performed without waiting for the timing by the timer. 4. When receiving a data write request to the non-volatile memory, the data in the non-volatile memory is periodically saved to a non-volatile memory for backup, which is different from the non-volatile memory, and the data and the history are stored. The data access method to the non-volatile memory according to claim 1, wherein the data is saved in the non-volatile memory for backup in units of designated items. 5. When receiving a data writing request to the non-volatile memory, when the data writing to the non-volatile memory exceeds the maximum number of times of writing, a maintenance person or the like is notified in advance before the maximum number of times of writing is reached. The method for accessing data to the non-volatile memory according to claim 1, further comprising: