JPH0541022A - Data backup system for electronic disk device with saving disk - Google Patents

Abstract

PURPOSE:To shorten the saving time when a power source is cut off by saving a track data to a fixed disk when the data is renewed during its employment and saving only a renewed data when the power source is turned off. CONSTITUTION:Upon receipt from a port control part 1 of an instruction from a host device H, whether it is a data renewal instruction or not is decided by a memory control part 5, and when it is the data renewal instruction, a data part is renewed, and afterward a renewal flag is set in a control part of the lead of a track and then written in a semiconductor memory 6. Then, when a read command is received from a fixed disk SVD control part 2, the data is transferred by the control part 5 to the SVD control part 2. Afterward, the renewal flag in the control part of a read track is reset and the renewed control part is written in the memory 6. By this method, the saving time to the fixed disk at the time of cutting off the power source for the electronic disk device can be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic disk device using a semiconductor memory, and more particularly to saving data when power is turned off.

[0002]

2. Description of the Related Art The following two methods have been adopted for backing up data on a memory in a conventional electronic disk device by a fixed disk in the device when the power is turned off.

1. When the power-off instruction is received from the host device, the backup mode is entered and the power is not turned off immediately until the save to the fixed disk is completed.

2. Alternatively, when the battery is held and the power-off instruction is received, the power is immediately turned off, but during the save period, the battery holds data in the memory and drives the save disk to save the data.

[0005]

In the above-mentioned electronic disk device, in order to save the data on the memory when the power is turned off, the larger the capacity of the electronic disk device, the longer the save time becomes. Therefore, if the above method 1 is adopted, even if a power-off instruction is issued, the power cannot be turned off forever.

Further, although the power supply can be cut off by the above method 2, the data of the electronic disk device having a large capacity must be held in the battery during the save period, and the fixed disk can be driven for a long time. There is a problem that a large capacity battery is required and a battery case must be provided.

The present invention has been made in view of the above-mentioned conventional circumstances, and therefore an object of the present invention is to solve the above-mentioned problems inherent in the prior art and to shorten the save time at the time of power-off. An object of the present invention is to provide a new data backup method for an electronic disk device with a save disk function that is enabled.

[0008]

In order to achieve the above object, a data backup method of an electronic disk device with a save disk function according to the present invention stores a semiconductor memory for backing up data with a fixed disk when power is turned off. In the electronic disk device used as the means, a Bit that stores that the control unit at the head of the track has been updated.
(Hereinafter referred to as "update flag"), means for activating the update flag when there is an update in the track data of the electronic disk device from the host device, and a control unit and a data area on the memory in track units at regular time intervals. Reading means, means for moving the head of the fixed disk to a save area of the fixed disk corresponding to a data area to be read next by the time until the reading means is executed, and a control section read by the reading means When an update flag indicating that the update has been performed is added to the fixed disk, a means for writing to the fixed disk in track units together with the following data, and a means for invalidating the update flag when the saving of the updated track data is completed And is configured to save data when the power is turned off, only the tracks for which the update flag of the control unit is valid are saved. It is characterized in that it has to cormorants.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the accompanying drawings with reference to the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of an electronic disk device with a save disk mechanism according to the present invention.

Referring to FIG. 1, reference numeral 1 denotes a port control unit, which is an electronic disk unit (EDU).
And the interface of the host device. Reference numeral 2 denotes a control unit of the save disk (SVD) 3, and this SVD control unit 2 is connected to the memory control unit 5 via the EBUS 4. Reference numeral 5 is a memory control unit for controlling the semiconductor memory 6 similarly to a fixed disk.

FIG. 2 is a specific block diagram of the SVD control unit 2 shown in FIG.

Referring to FIG. 2, reference numeral 11 denotes a semiconductor memory recess control circuit, which is a memory control unit 5 at fixed time intervals.
The semiconductor memory 6 can be accessed via.
12 and 13 are memories or FI for temporarily storing the data read by the memory access control circuit 11.
It is FO. An SVD control circuit 14 controls the fixed disk (SVD) 3. Reference numeral 15 is a circuit for checking the control unit (PA) of the data read by the memory access control circuit 11.

FIG. 3 is a concrete block diagram of the memory controller 5 of FIG. 1, which controls the update flag.

Referring to FIG. 3, the port control unit 1 interfaces with a host device, and the command analysis unit 21 analyzes a command sent via the EBUS 4. Reference numeral 22 is a circuit for operating a flag in the control unit of the track when the data of the track is updated or saved in a fixed disk (SVD) when the data of the semiconductor memory 6 is updated. 23
Is a memory control circuit for controlling the memory.

FIG. 4 is a data map when the electronic disk is regarded as a fixed disk, and there is a control unit (PA) storing control information at the head of each track. A flag indicating whether or not a part of this track has been updated is provided in this.

The operation of the present invention will be described below.

First, the operation relating to the update flag will be described.

(1) When receiving a series of operation instructions from the host device from the port controller 1 in FIG. 3, the command analyzer 21
At, it is determined whether the command is a command for updating data. At that time, if the data update is instructed, the update flag in the control unit (PA) at the head of the track where the data was updated is set in the update flag control circuit 22 after the data part is updated by the instruction. Then, write in the memory 6.

(2) Further, when a read command is received from the SVD control unit 2 of the electronic disk device, the command analysis unit 2
Analyze the instruction in 1 and EB the data to SVD control 2
Transfer via US4. Thereafter, the update flag of the control unit of the read track data is set to the update flag control circuit 22.
And the updated control unit (PA) is written in the memory 6.

Next, the operation of the SVD controller will be described.

(1) During operation, the memory access control circuit 11 of FIG. 2 reads data in units of one track to the memory control unit 5 via the EBUS 4 at intervals that do not hinder access from the host device. Request. The number of tracks to be read is gradually increased to 0, 1, 2, ..., N, n + 1. At this time, before issuing a request to the memory control unit 5, the SVD control circuit 14 is instructed to move the SVD head to the SVD track position corresponding to the requesting track. By doing so, there is no physical waiting time for moving the head. The data sent from the memory controller 5 is the track buffer 12
Or written in 13. At this time, it is checked whether or not the data read by the PA check unit 15 needs to be written in the SVD. If it is necessary to write the data written in the track buffer 12 or 13 into S
Write in sync with VD.

(2) Next, when the power is turned off, the memory access control circuit 11 sends the track 0,
Commands are issued in the order of 1, 2, ..., N, n + 1. The read data is stored in the track buffers 12 and 13
Is written alternately on each track. At this time, if the data written in the track buffer is not updated, it is not necessary to write the track in the SVD, so the track data is destroyed and the process is advanced to the next track.

[0024]

As described above, according to the present invention,
In the control method of the save disk (SVD) of the electronic disk device (EDU) with the save disk mechanism, the track data updated by the access from the host device is checked in a fixed time unit during operation, and if there is an update, By providing a function to save the track data to SVD sequentially, and saving only the updated track data when the data is saved at the end of the operation, the data save time at the end of the operation is greatly reduced. Therefore, the power-off time of the electronic disk device can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an electronic disk according to the present invention.

FIG. 2 is a block configuration diagram showing a specific example of the SVD control unit shown in FIG.

FIG. 3 is a block configuration diagram showing a specific example of a memory control unit shown in FIG.

FIG. 4 is a schematic diagram showing a data configuration example of an electronic disk according to the present invention.

[Explanation of symbols]

1 ... Port control unit 2 ... SVD control unit 3 ... Auxiliary storage device (fixed (save) disk (SV
D)) 4 ... EBUS 5 ... Memory control unit 6 ... Semiconductor memory 11 ... Memory access control circuit 12, 13 ... Track buffer 14 ... SVD control circuit 15 ... Update flag detection circuit (PA check) 18 ... Memory control unit 21 ... Command Analysis unit 22 ... Update flag control circuit 23 ... Memory control circuit

Claims (1)

[Claims] 1. A bit (hereinafter referred to as an update flag) for storing that an update has been made in a control unit at the head of a track in an electronic disk device using a semiconductor memory as a storage means for backing up data on a fixed disk when power is turned off. Called)) and means for activating the update flag when the track data of the electronic disk device is updated from the host device, and means for reading the control unit and the data area on the memory in track units at regular time intervals. , Means for moving the head of the fixed disk to a save area of the fixed disk corresponding to a data area to be read next by the time until the reading means is executed, and updating to the control unit read by the reading means If the update flag indicating that the And a means for invalidating the update flag when the saving of the updated track data is completed, and in the data save when the power is turned off, the track to which the update flag of the control section is added is provided. A data backup method for electronic disk devices with a save disk, which is characterized by performing only a save.