JPH0291717A - File backup system - Google Patents

Abstract

PURPOSE:To back up an important file without any sense by making plural drive selections effective only in backup mode, allowing and inhibiting an interruption from a drive accordingly, and recognizing the interruption. CONSTITUTION:This system is equipped with a connection cable 1 which is used for a daisy chain system, hard disk controllers(HDC) 2 and 4, hard disk drives(HDD) 3 and 5,and a host interface circuit 6. Then a backup mode is entered and both drives 3 and 5 are made ready; and one drive 3(5) is set in an interruption ready state and a write command is generated after data is loaded in a sector buffer, so that a file controller 2(4) operates to write the data on a file device. Those file controllers 2 and 4 operate asynchronously, so they know the end from the end of the interruption; and those are repeated alternately to know the end of backup operation. Consequently, the important file can be backed up without any sense.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a file backup method.

(Prior art) Recently, personal combinators (hereinafter simply referred to as PCs) and work stage machines (hereinafter simply referred to as WS) have been developed.
It is becoming common knowledge for a class of combination vehicles to be equipped with a hard disk drive as standard, and the storage capacity of these devices has increased from 40MB (megabytes) to 100MB, and is said to reach around 300MB in the near future.

The issue here is how to protect the memory contents. Up until now, there was not that much difference between the capacity of a floppy disk and the capacity of a hard disk, so backup files could fit on a floppy disk, at most 10 disks. However, when the hard disk capacity reaches 40 MB, 20 to 30 floppy disks are required, no matter how large the capacity.

In addition, things that had not been a concern before, such as the time required to save a file and the storage location of a floppy disk, have come to the fore.

(Problem to be Solved by the Invention) Recently, in order to solve the above-mentioned problem, a large-capacity streamer tape device has appeared, and attempts have been made to save backup files on a cassette chip. However, the Streamer Theso device also has drawbacks listed below.

(1) Since it is a sequential file, it takes time to save/load.

(2) Since the file format has not yet been standardized, problems may arise in the future regarding file compatibility.

The present invention has been made in view of the above drawbacks.

The purpose of the present invention is to provide a file backup method in which another hard disk device of the same type is prepared and a backup file is created in parallel with normal file writing.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a computer system that includes a plurality of file controllers in which when a drive select signal is in a state, other signals become valid. 1. Means for disabling one drive select in normal operating mode and enabling multiple drive selects only in backup mode, and accordingly enabling/disabling interrupts from drives and recognizing these interrupts. This system is configured with means for recognizing the end of backup.

(Operation) In the above configuration, the backup mode is set to put both drives in the READY state, and one drive is set in the interrupt enabled state. When a write command is issued after loading data into the sector buffer, the file controller operates and writes the data to the file device. Since each file controller operates asynchronously, its termination is known by the termination of an interrupt. By repeating this alternately, you will know when the backup is complete.

This allows you to back up important files without being aware of it.

(Example) Examples of the present invention will be described in detail below.

FIG. 1 is a diagram showing a connection system of a hard disk device used in the present invention. In fig.

Reference numeral 1 denotes a connection cable used in a daisy chain system, and all signals except the drive select signal are connected by wired OR. 2 is the hard disk controller (I
DC÷1), hard disk drive (HDDφ1)
Control 3. Bares 2 and 3 are hard disk drives that can be normally accessed by software. 4 is also a hard disk controller (IDC≠2), which controls the hard disk drive (HDD+2) 5. Bearings 4 and 5 are hard disk drives for file backup, which is the key point of the present invention. 6 is a host interface circuit, the details of which are shown in FIG.

FIG. 2 shows a host interface circuit accessed by a PC or WS processor.

3 shows additional circuitry for implementing the invention. In the figure,
61 is a flip-flop (hereinafter referred to as F/F) that is set/reset by the OUT instruction of the processor (hereinafter referred to as CPU)
It is. The Q output of F7F61 is and dart (A) 63
is input to control drive select≠2 (line 13). 62 is an F/F that is set/reset by the CPU's OUT command, and its Q output (line 12) controls drive select +1 and also controls drive select +2 through AND/DATERO 3. and date 63
When the output of F/F61 (line 14) is @1#O, F/
Drive select +2 (line 12) of F6Z output (line 12)
It is output to line 13), and when it is 'O', line 13 is made inactive.

F/F 64 is IDC+1 (,') KF/F6
5 exists in I(DC+2(4)), and both CPU
This is an F/F that is set/reset by the OUT command.

The Q output of F/F64 is input to Andr-Toro 6,
) (Interrupt signal from DD÷1 (3) (IREQ÷1)
Allow/prohibit. Similarly, the Q output of the F/F 65 is input to the AND/DART 6t7, which enables/disables the interrupt signal (IRE(1,?) from the HDD/2(5)).

Andr-Toro 6 and 67 are wiped-ORed on the host interface. BUSY flowing through line XO
The (busy) signal indicates that the node disk drive is in operation and is wired ORed so
When both DD S1/Dish D÷2 are in the READY state, the CPU recognizes it as READY, and the data
Commands and other information can be transferred.

Hereinafter, the operation of the embodiment of the present invention will be explained in detail. H
To write to DC/) IDD, when the BUSY signal is inactive, load one sector worth of data into the built-in sector buffer and then issue a write command, IDC+1(2) becomes 1 (DD+1( 3), and when completed, issues an interrupt signal to notify the CPU of the completion.Data, command 9, and other information are written to IDC+1 (2) only when the Drino Select signal is active. It receives the information given to it and starts a predetermined action.

Commands other than writing are not directly related to the present invention and will therefore be omitted.

Here, the backup operation of the present invention will be explained with reference to FIG. When the F/F 61 is in the reset state (Q="O"), the AND/DART 63 is prohibited, so the drive select +2 (line 13) is inactive. In this case, IDC+2 (4) does not respond to any of the host interface signals; therefore, as a hard disk device, HDC+1/I (DDS1 (2/3)
) is the same as if only one was equipped. This is normal mode operation.

Next, the backup mode will be explained.

Set F/F61. This indicates backup mode. At this time, when F/F 62 is set, AND gate 63 is enabled, so drive selector 1
, drive select≠2 becomes active, and the same data is placed in each IDC +1 (,?), +2 (4),
Commands and other information can be transferred.

However, at this time, F/F6 controls interrupt enable/disable.
4 and 65 are set in the F/F 64 (enabling engineering part Q+1) and reset in the F/F 65 (prohibiting IREQ+2). When a write command is issued after loading data into a sector buffer (not shown), IDCs (2) and (4) start operating and transfer the data in the sector buffer to HDD+1 (J), Write to +2 (5). Since DCs 1 (3) and +2 (, 5) of my husband operate asynchronously with each other, their termination is triggered by an interrupt signal I R
You will find out through EQ.

The CPU detects I_REQsu1 at the first I_REQ. Next, F/Fs 64 and 65 control interrupt enable/disable.
Reset the state of F/F64 (disable IREQ+1)
, reset F/F 65 to set (IREQφ2 is enabled). The CPU detects I REQφ2 at the next I REQ.

In other words, the CPU detects IREQ twice and
) It can be recognized that the operations of both IDDφ1 and HDC/HDDφ2 have been completed.

With the above operations, the same data is written to the same sector in each )[)D. By repeating this operation, a predetermined file can be written to HDD S2 with the same contents as HDD φ1. If you are writing a file that does not require backup, no time loss will occur unless you set the F/F 61.

[Effects of the Invention] As explained above, according to the present invention, it becomes possible to back up one important file without being aware of it.

The present invention is economical because it requires less additional circuitry if it is a hard disk drive that has a buffer memory and uses a bar-disk control system.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a connection system of a node disk device in which the present invention is realized, and FIG. 2 is a diagram showing an additional circuit for realizing the present invention. 6...Host interface circuit, 61, 62.

Claims (1)

[Claims] When one drive select signal is in the state, other signals are valid.In a computer system equipped with multiple file controllers, the CPU controls one drive select, and in normal operation mode, one drive select is prohibited, and only in backup mode, multiple file controllers are enabled. A file backup method characterized by comprising means for enabling drive selection, means for permitting/disabling interrupts from the drive in accordance with this, and means for recognizing the end of backup by recognizing this interrupt.