JPH0664828B2 - Floppy disk drive control system - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a system having a plurality of Flotpies disk drives, in which the Flotpies disk drives are particularly daisy-chained to a Flotpies disk controller. And a floppy disk drive control method suitable for.

[Technical background of the invention and its problems]

In recent years, in systems such as personal computers and small business computers, Floppy disks, such as 5.
In many cases, a plurality of floppy disk drives (hereinafter, referred to as FDD) to which a 25-inch floppy disk is applied are connected to a floppy disk controller (hereinafter, referred to as FDC). In such a system, one connection cable is required to connect each FDD to the FDC.
Mainly the daisy chain connection method is adopted so that it can be done with a book.

FIG. 1 shows an example of connection signals between FDC and FDD, and these connection signals also include a motor on / off signal for controlling a motor that rotationally drives a floppy disk (storage medium). In the system as described above, each FDD is also daisy-chain connected to the line of this motor on / off signal, so that the motor on / off signal is commonly transmitted to each FDD, causing the following problems.

Now, it is assumed that processing such as data reading / writing (FDD processing) is performed on the FDD designated by the FDC according to a command from the host device. In this case, at least the motor of the designated FDD needs to be turned on as shown in the flow chart of FIG. However, in the above system, the motor on / off signal is transmitted to each FDD,
The FDD motor that is not specified (not processed) is also turned on. As a result, in the non-processed FDD, the floppy disk rotates at the same track position in contact with the magnetic head. If this state continues, the applicable floppy disk will have its durable life (eg 3 million passes /
The track will be reached soon. That is, the conventional system has a drawback that the durability life of the floppy disk is shortened even when the FDD process is not performed.

[Object of the Invention]

The present invention has been made in view of the above circumstances, and its purpose is to:
It is an object of the present invention to provide a floppy disk drive control system capable of preventing the durable life of the floppy disk from being spoiled.

[Outline of the present invention]

The present invention relates to a system in which a motor on / off signal from an FDC (Floppy disk controller) is commonly transmitted to each FDD (Floppy disk drive) in the system.
By performing idle seal regularly or irregularly on the FDD that is not subject to D processing, the floppy disk is prevented from rotating while maintaining contact with the magnetic head at the same track position. It is a thing.

Example of Invention

An embodiment of the present invention will be described below with reference to the drawings. FIG. 3 shows a system to which the present invention is applied, for example, a personal computer system. In the figure, 1 is a microprocessor for controlling the entire system, 2 is a main memory for storing various programs and data, and 3 is a programmable timer. Reference numeral 4 is an FDC, and 5 and 6 are FDDs connected to the FDC 4 by a cable 7 in a daisy chain (any connection method in which information is commonly transmitted).
A schematic of the signals passing through this cable 7 has already been shown in FIG. Reference numeral 8 is a system bus which connects the microprocessor 1, the main memory 2, the programmable timer 3, the FDC 4, and the like.

Next, the operation of the embodiment of the present invention will be described with reference to the flow charts of FIGS. Now, suppose that the microprocessor 1 has given a command to the FDC 4 to make the FDD 5 the FDD processing target. This allows FDC4
The FDD processing routine (refer to the flow chart in FIG. 4) is started. In this FDD processing routine, the FDC 4 first determines whether or not a motor on / off signal designating on is output (step S11). If the determination in step S11 is YES, FDC4 directly
Similarly, if the judgment is NO, the motor on / off signal is turned on (step S13), and then step S13.
Go to 12. At step S12, the FDC 4 determines whether or not the given command is correct. The operation up to this point is the same as before (see FIG. 2). If the determination in step S12 is NO, FDC4 performs the operation of setting the invalid command status as in the conventional case (step S12).
S14). On the other hand, if the determination in step S12 is YES, F
DC4 determines whether or not an idle seek flag (not shown) is on (step S15). This idle seek flag indicates whether or not the unspecified FDD can idle seek before entering the processing of the specified FDD number (in other words, the idle seek is performed on the unspecified FDD). This is a flag for indicating whether or not to perform. Here, the idle seek is to perform a seek operation for changing the current track irrespective of a command from the host device and without the purpose of read / write. In this embodiment, the idle seek flag is turned on by a timer processing routine (which is one of FDD processing routines) in FDC4. This timer processing routine is started by an interrupt signal generated from the programmable timer 3 for a fixed time, for example, every 20 msec. In the timer processing routine, as shown in the flow chart of FIG. 5, it is first determined whether or not the idle seek flag is on (step S31). In the case of NO determination, the software counter (which may be a hardware counter) is incremented by 1 (step S32), and then it is determined whether or not 1500 times have been counted (step S33). YE in this step S33
If the result is S, the idle seek flag is turned on (step S34). At this time, it is necessary to clear the software counter. As is apparent, in this embodiment, the idle seek flag is basically turned on once every 30 seconds.

Referring again to the flow chart of FIG. 4, step S1
When YES is determined in 5, that is, when it is determined that the idle seek flag is turned on, FDC4 is different from the specified FDD (FDD5 in this example) (in this example, FDD4).
FDD6), that is, an FDD that is not a processing target is designated (step S16). Next, FDC4 is the FDD specified in step S16 (FDD
It is determined whether or not the current track (6) (the track on which the magnetic head is located) is the innermost track (step S17), and if the result is NO, the current track is, for example, one track in the inner circumference direction. Seek (idle seek) (step S18). On the other hand, YES at step S17
In the case of determination, the FDC 4 seeks the current track to the outermost position (track 0) (idle seek) (step S19). The operations of these steps S18 and S19 are performed by issuing a seek command after designating the corresponding track number.

When FDC4 executes step S18 or step S19, it turns off the idle seek flag (step S20). Then F
The DC4 returns the designated FDD from the non-processing FDD (FDD6) to the FDD (FDD5) which is the processing target (step S21), and then performs the processing corresponding to the command (step S22). If NO is determined in step S15, that is, if it is determined that the idle seek flag is off, the command processing in step S22 is directly executed.

As described above, according to the present embodiment, the idle seek is performed for the non-processed FDD (the FDD on the side not accessed by the software) at regular intervals (30 seconds in this example), and the current track is set. Since each track is changed in a fixed direction, it is possible to prevent the inconvenience that the floppy disk continues to rotate for a long time with the same current track.

In the above embodiment, the case where the current track is changed by one track by the idle seek has been described, but the number of changed tracks is not limited to this. Also,
In the above embodiment, the idle seek flag is turned on once every 30 seconds, but the present invention is not limited to this. Also,
The routine for turning on the idle seek flag (see FIG. 5) is not limited to the interrupt signal from the programmable timer 3, and may be started by a timer mechanism inside the FDC 4, for example.

Although the processing speed becomes slow, the idle seek may be always performed in the FDD processing. In this case, the idle seek flag indicating whether or not idle seek is possible and the time management mechanism (routine in FIG. 5) for the flag are unnecessary.

Further, in the above-mentioned embodiment, the case where the FDD is applied to a system in which two FDDs are connected, but in the case of a system in which the FDD is three or more, simply checking the FDD number makes What the idle seek can do can be easily judged from the flow chart of FIG. Further, it is obvious that the present invention can be applied not only to the FDD to which the 5.25-inch floppy disc is applied but also to other FDDs.

〔The invention's effect〕

As described in detail above, according to the present invention, an FDD that is not a processing target is processed.
Since it is possible to prevent the floppy disk from continuing to rotate for the same track for a long time, it is possible to prevent the durable life of the floppy disk from being spoiled.

[Brief description of drawings]

Figure 1 shows FDC (Floppy disk controller) and FDD.
FIG. 2 is a diagram showing an example of a general connection signal with a (floppy disk drive), FIG. 2 is a flow chart for explaining the operation of a conventional example, and FIG. The system configuration diagram shown in FIGS. 4 and 5 is a flow chart for explaining the operation of the above embodiment. 4 ... Flotpie disk controller (FDC), 5, 6 ...
… Floppy Disk Drive (FDD), 7… Cable.

Claims (1)

[Claims] 1. A plurality of floppy disk drives and a floppy disk controller for controlling the specified floppy disk drive in response to a command from a host device, and a motor on / off from the floppy disk controller. In a system in which a signal is commonly transmitted to the plurality of floppy disk drives, when processing the floppy disk drive designated by the host device, the floppy disk drives not designated are periodically or A floppy disk drive control method characterized by being configured to execute idle seeks irregularly.