JPS61201356A - Memory device - Google Patents

Abstract

PURPOSE:To eliminate the need for an incorporated secondary power source by incorporating a magnetic disk in a semiconductor file memory device and saving the contents of a semiconductor memory thereupon, and realizing nonvolatility in power-off operation. CONSTITUTION:When access for writing is attained by a processor 1, an access acceptance control circuit 21 sends an address to a semiconductor memory part 22 and also registers a write address in an address control table 23. A magnetic disk control circuit 24 accesses the address control table 23 independently and reads the write address through an address readout path 35 when the write address is registered. The magnetic disk control circuit 24 when saving data discriminates the contents of a control signal line 34 between controllers so as to avoid a competition against access from a processor 1 and sends a data transfer indication to the access acceptance control circuit 21 when access is not performed, thereby saving the data.

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary of the Invention] The present invention provides a magnetic disk drive without using a battery in order to reduce costs, reduce size, improve maintainability, and take measures to make semiconductor memory non-volatile. The contents of the semiconductor memory section and the magnetic disk memory section are managed so that they are the same at the time of initial setting and always thereafter using the write address management table. It is designed to hold.

[Industrial application field]

The present invention relates to a memory device, and particularly to a semiconductor memory device that takes measures for non-volatility.

[Conventional technology]

Conventionally, semiconductor memory has high speed but is expensive, so it has not been used for files, but has generally been used as a storage element of a main memory device. However, in recent years, as semiconductor memory has become more highly integrated, costs have been reduced.
It has become possible to configure devices with relatively large capacities at low cost, and information processing systems are becoming more and more likely to fill the access gap between main storage and file storage devices such as magnetic disks. In other words, there is a growing demand for high-speed file storage devices with little difference in access time between the two, and for these reasons, file storage devices using semiconductors have come to be constructed.

However, since semiconductor memory does not have non-volatility when the power is turned off, when used as a file storage device, some kind of non-volatile measure is required.

For this reason, conventional measures have been taken as described in (a) and (b) below.

(,) The device has a built-in battery, so when the power is turned off.

A method of retaining memory contents using this battery.

(b) A battery and a magnetic disk are built into the device;
A method of evacuating data to a magnetic disk while retaining the memory contents of semiconductor memory using a battery when the power is turned off.

However, if these countermeasures are taken.

The following problems arise. First of all, regarding the above (,), the battery is sufficient for the maximum file capacity retention time.

It is extremely uneconomical as it must be installed from the beginning, and since it has a built-in battery, it is not possible to miniaturize the device.Furthermore, due to voltage drop due to aging of the battery, it is necessary to regularly measure the capacity and replace it. As the capacity increases, maintenance becomes more difficult. Regarding (b) above, it has the advantage of requiring less battery capacity because the retention time of memory content is shorter than in (a), but it also has the advantage of being economical, downsizing, and the use of batteries and magnetic disks. In terms of maintainability, etc., there are problems similar to those in (,) above. Therefore, further advantageous non-volatization measures are desired.

[Purpose of the invention]

The purpose of the present invention is to meet such demands.

It is an object of the present invention to provide a storage device that is economical, compact, and maintainable, and that can retain stored contents when the power is turned off.

[Structure of the invention]

In order to achieve the above object, the present invention provides a storage device.

In a storage device connected to a processing device and provided with a memory means consisting of a volatile memory element, the memory means consisting of a non-volatile memory element and, at the time of initialization, from the non-volatile memory means to the volatile memory means; a control means for transferring the entire data area from the volatile memory means to the non-volatile memory means; and a control means for responding to an access from the processing device with the volatile memory means, and during the access, the contents of the volatile memory means are and control means for autonomously and asynchronously transferring the rewritten block data from the volatile memory means to the nonvolatile memory means and writing the data at a time other than when responding to the processing device. There are characteristics.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a storage device showing an embodiment of the present invention.

In the figure, 1 is a processing device, 2 is a semiconductor file storage device, 21 is an access reception control circuit, 22 is a semiconductor memory section, 23 is a write address management table, 24 is a magnetic disk control circuit, and 25 is a magnetic disk memory section. .

Regarding the signal lines, 11 is an address bus, 12 is a data bus, 13 is a control signal line, 14 is a command instruction signal line,
31 internal address bus, 32 internal data bus, 3
3 is a control signal line within the device, 34 is a control circuit amount control signal line,
35 is an address read bus, 36 is a magnetic disk address bus, and 37 is a magnetic disk control signal line.

As shown in FIG. 1, in this embodiment, only a magnetic disk device is added without using a battery, and the write address management table 23 allows the contents of the semiconductor memory section and the magnetic By managing the contents of a disk memory part so that they are the same, the stored contents are retained even when the power is turned off.

The processing bag ELt in FIG. 1 sends out a read or write instruction signal via the control signal line 13, and at the same time sends out an address indicating the read/write location in the semiconductor memory section 22 via the address bus 11. The access reception control circuit 21 is a processing device! ! When an access request from 1 is received, if the control signal line 13 indicates a read instruction, a read instruction is sent to the semiconductor memory unit 22 via the internal control signal line 33, and an address is further sent via the internal address bus 31. As a result, the semiconductor memory section 22 reads out the data at the address and transfers it to the internal data bus 32.
The access reception control circuit 21 sends the received data to the processing device 1 via the data bus 12.

Through the above operations, the processing device 1 can read data from the semiconductor file storage device 2.

Further, when the control signal 13 from the processing device 1 is a write instruction, the access reception control circuit 21.

The data received via the data bus 12 is sent to the semiconductor memory unit 22 via the internal data bus 32, and
A write instruction is sent via an internal control signal 33, and an address is sent via an internal address bus 31, respectively. Thereby, the semiconductor memory section 22 can write write data to the address. The above is the processing device i! 1 is an outline of the operation when the semiconductor file storage device 2 is accessed from 1.

Next, in addition to the above operations, the semiconductor file storage device 2 performs an autonomous data transfer operation from the semiconductor memory section 22 to the magnetic disk memory section 25 as described below.

First, when there is a write access from the processing device I, the access reception control circuit 21 sends an address to the semiconductor memory section 22 and simultaneously registers the write address in the address management table 23.

The magnetic disk control circuit 24 autonomously accesses this address management table 23.

Once the write address is registered, the address read bus 3
5 to read its address. The magnetic disk control circuit 24 first performs an operation to save data at the address from the semiconductor memory section 22 to the magnetic disk memory section 25, but at this time, in order to avoid conflict with access from the processing device I, the control table is The access reception control circuit 21 controls the processing device i! Is it being accessed from t?

Or it is not accessed by the processing device 1.

The magnetic disk control circuit 24 identifies whether it is inactive. If access is in progress, the magnetic disk control circuit 24 waits until the access is completed, but if it is not in operation, the magnetic disk control circuit 24 sends a data transfer instruction to the access acceptance control circuit 21. As a result, data is read from the semiconductor memory section 22 and sent to the magnetic disk memory section 25 via the internal data bus 38, and an address is written via the magnetic disk address bus 36 and the magnetic disk control signal line 37. Each instruction is sent to the magnetic disk memory section 25, and the data in the semiconductor memory section 22 is saved. Through these operations, the semiconductor file storage device 2 can always save data that has been rewritten by writing from the processing bag @1 into the magnetic disk memory unit 25.

Further, the semiconductor file storage table @2 is stored in the semiconductor memory section 22. In order to make the storage contents of the magnetic disk memory section 25 the same, the entire data is autonomously transferred from the magnetic disk memory section 25 to the semiconductor memory section 22 when the power is turned on.

Such transfer of the entire data can also be performed by sending a command from the processing device 1. When a command is sent from the processing device 1, a command instruction signal line 14 is used to notify that it is a command instruction signal, and an address bus 11 is used to send a command for data area transfer.

Depending on the content of the command, the semiconductor file storage device 2
From the semiconductor memory section 22 to the magnetic disk memory section 25,
Alternatively, the entire data is transferred from the magnetic disk memory section 25 to the semiconductor memory section 22.

In this way, in this embodiment, (a) write/read operations by access from the processing device 1, and (b) data saving operations of data written in the semiconductor memory section 22 to the magnetic disk memory section 25. , and (c) from the semiconductor memory section 22 to the magnetic disk memory section 25 at the time of initial setting.
By transferring the entire data from the magnetic disk memory section 25 to the semiconductor memory section 22, the storage contents of the semiconductor memory section 22 and the magnetic disk memory section 25 can always be kept the same. Even after the power is turned off, the file storage contents that existed immediately before the power was turned off can be retained.

〔Effect of the invention〕

As explained above, according to the present invention, a magnetic disk is built into the semiconductor file storage device and the contents of the semiconductor memory are saved there, thereby achieving non-volatility even when the power is turned off. Compared to conventional semiconductor-based high-speed file storage devices, it eliminates the need for a built-in secondary power source such as a battery, and uses small magnetic disks whose capacity has been increasing in recent years. This has the advantage of being economical, compact, and easy to maintain.

[Brief explanation of the drawing]

FIG. 1 is an internal configuration diagram of a semiconductor memory device showing one embodiment of the present invention. 1: Processing device, 2: Semiconductor file storage device. 11 Near address bus, 12: Data bus, 13: Control signal line, 14: Command instruction signal line, 21: Access reception control circuit, 22: Semiconductor memory section, 23 Near address management table, 24: Magnetic disk control circuit, 25 : Magnetic disk memory section, 31: Address bus within the device, 32 = Data bus within the device, 33: Control signal line within the device, 34: Control circuit amount control signal line, 35 Near address read bus, 36:
Magnetic disk address bus, 37: magnetic disk control signal line, 38: internal data bus. --7'

Claims (1)

[Claims] (1) In a storage device connected to a processing device and equipped with a memory means consisting of a volatile memory element, the memory means consisting of a non-volatile memory element and the volatile memory means are connected to the non-volatile memory means at the time of initial setting. or from the volatile memory means to the non-volatile memory means, a control means for transferring the entire data area to the non-volatile memory means; control means for autonomously and asynchronously transferring the block data whose contents have been rewritten from the volatile memory means to the non-volatile memory means and writing the data at a time other than when responding to the processing device; A storage device comprising: