JPS6070549A - Control device of floppy disc - Google Patents

Abstract

PURPOSE:To control the head loading and unloading state of plural floppy disc devices individually under control by a CPU by forming an output port for outputting a drive selection signal-enable signal and a head loading signal. CONSTITUTION:Although a drive select ''0'' signal 30a and a drive select ''1'' signal 30b are supplied from a floppy disc controller LSI20a through a driver 20c, the driver 20c determines the valid state and invalid state of both the drive select signals 30a, 30b on the basis of the state of the drive select-enable signal 31a supplied from an output port 20d under control by the CPU22. On the other hand, the output port 20d supplies the 1st head loading signal 31b and the 2nd head loading signal (motor ON signal) 31c to respective floppy disc devices 26a, 26b under the control by the CPU22. Thus, it is possible to control the loading and unloading state of respective heads of a pair of floppy disc devices 26a, 26b individually on the basis of a command from the CPU22.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a floppy disk control device, and more particularly to a floppy disk control device for driving each motor of a plurality of floppy disk drives (floppy disk devices) connected to the same system. The present invention relates to a floppy disk control device that can individually control the loading and unloading states of heads in each floppy disk drive.

BACKGROUND OF THE INVENTION Floppy disk devices have been used as randomly accessible storage devices, and 8-inch series, 5-inch series, etc. have been developed and are widely used. A floppy disk controller is used to control the writing and reading operations of a floppy disk as a storage device.
It functions as an interface between the floppy disk device and the host computer. An overview of such a floppy disk device is shown in FIG.

As shown in FIG. 1, a floppy disk control device 1
The C
Performs interface control between PtJ2 and FDDs 3a to 3d. In the system shown in Figure 1, 4
Floppy disk devices 3a to 3d are connected to the floppy disk control device 1. The floppy disk controller 1 controls these floppy disk devices 3.
A to 3d are selectively driven to control the writing and reading of data in the selected floppy disk device, thus controlling the floppy disk device itself and formatting and controlling the data on the floppy disk. It has the function of

As shown in Figure 1, the floppy disk controller is a CPU that interfaces with CPtJ2 on the host side.
an interface 1a, an FDC control unit 1b that performs data writing/reading control and data format control;
It has an FDD interface 1C that controls the driving of the floppy disk devices 3a to 3d. The CPU interface 1a connects to the host side CPU 2 via the bus.
The CPU interface 1a mainly consists of a data bus, an address bus, a control bus, and various registers connected to these buses, such as command registers, status registers, data registers, track registers, and sector registers. and command.

It has the function of controlling the exchange of status, track address, sector address, etc., and data transfer. F.C.
The C control unit 1b has functions of controlling head positioning and controlling data writing and reading according to a predetermined data format. For example, in response to a command from the CPU 2, a predetermined sector of the selected floppy disk is searched, the data on the floppy disk is serial-parallel converted, and the data is transferred one byte at a time to the CPtJ2. There are two types of data transfer: a program transfer method in which data is transferred via the CPtJ2, and a DMA transfer method in which data is directly exchanged using hardware without going through the CPU2. The FDD interface 1C connects the FDC controller 1b and each floppy disk device 3a to 3d.
It consists of drivers, receivers, and terminators necessary for transmitting and receiving signals between the terminal and the terminal, and a data separator for separating read data into data and clock. or,
A day chain method and a star chain method are used as methods for selectively driving and controlling the plurality of floppy disk devices 3a to 3d. In addition, as shown in FIG. 1, the memory 4 and the input/output device (Il
o) 5 is CPU 2 and floppy disk control device 1
and is connected to.

In the floppy disk controller shown in FIG. 1, an LSI for the floppy disk controller has been developed in which the function of an FDC control section 1b for controlling data format is incorporated into a single chip integrated circuit. Such floppy disk and controller LSIs are
It is also possible to incorporate one or more of the functions of the CPU interface 18 and the FDD interface 1c. In such a one-chip floppy disk controller LSI, a head load signal is used to control the operating state of the head of the floppy disk device, and such a head load signal is connected to the LSI. Used as a load instruction signal for two floppy disk devices, and as a CPU
Normally, the motor-on signal supplied under the control of floppy disk drive 2 is used as a motor-on instruction signal for each floppy disk device 3a to 3d. By the way, in a floppy disk device, when data is to be written or continuously output, the head is in pressure contact with the floppy disk, and in other cases, the head is separated from the floppy disk. . Figures 2a and 2b show an example of a head loading mechanism in a floppy disk drive; Figure 2a shows the head in an unloaded state, while Figure 2b shows the head in a loaded state. It shows the state of being in a state. In addition, in FIG. 28 and FIG. 2b, 10 is a floppy disk, 11 is a jacket, 12 is a head, 13 is a head opening/door arm, and 14
indicates a veil, and 15 indicates a pad. As described above, since the floppy disk 10 is in pressure contact with the head 12 at least when writing and reading data, the floppy disk 10 is subject to wear and tear. By the way, as shown in FIG. 1, when a plurality of floppy disk devices 3a to 3d are connected to the floppy disk control device 1, the floppy disk drive is opened so that the floppy disk that is selected and is in the driving state is head loaded. need to be done. For this purpose, it is necessary to add a drive select signal as an AND condition to the head load instruction signal supplied to each drive. However, with such a configuration, if a floppy disk is copied track by track between two floppy disk drives, the heads of each floppy disk drive will alternately load and unload. Not only does this repeatedly generate noise, but it also generates vibration, which causes problems with the durability and reliability of the device.

Purpose The present invention has been made in view of the above points, and solves the drawbacks of the prior art as described above, and enables head loading and unloading of a plurality of floppy disk drives under the control of a central processing unit on the host side. It is an object of the present invention to provide a floppy disk control device that makes it possible to individually control the unload state.

Configuration A specific embodiment of the present invention will be described in detail below with reference to FIGS. 3 and 4. As shown in FIG. 3, a floppy disk controller 20 which is an embodiment of the present invention
is connected to the central processing unit (CPU) on the host side via the bus 21.
)22. In the illustrated example, memory 2
3 and an input/output device (Ilo) 24 are also connected to the bus 21.

On the other hand, the floppy disk controller 20 is connected via a bus 25 to a pair of floppy disk devices 26a and 26b. In this embodiment, the pair of floppy disk devices 26a and 26b are connected in a daisy chain manner.

The floppy disk controller 2o is an LSI for a floppy disk controller configured as a one-chip TC.
The LSI 20a is connected to the CPU 22 via a bus 21. This floppy disk controller L8120a has an interface function with the CPU 22, as well as data input/output control and format control functions. The floppy disk controller LSI 20a is connected via a bus 25 to a pair of floppy disk devices 26a and 26b in a daisy chain. The floppy disk control device 20 further includes a data separator 20b,
Floppy disk drive 26 selectively activated
It has a function of separating the read data read in a or 26b into a reception clock signal and a data signal and supplying them to the floppy disk controller LSI 20a. Note that the data separator 20b may be LS if desired.
It is also possible to integrate it into I20a. The floppy disk controller @2o further includes a driver 20c that drives each floppy disk device I@26a and 26b, and selectively brings each floppy disk device 26a and 26b into a driving state, as will be described later. Provides a drive select signal for A first drive select signal line 30a is connected from the floppy disk controller LSI 20a to the floppy disk device 26a via the driver 20c, and a second drive select signal line 30b is also connected from the floppy disk controller LSI 20a to the driver 20c. It is connected to a floppy disk device 26b. The first drive select signal line 30a is a drive select signal line.

It is for supplying signals to the floppy disk device 26a, and the drive select signal line 3゜b is for supplying the drive select 1 signal to the floppy disk device 26b.
It is for supplying to.

The floppy disk controller 2o further has an output port 20d, which is connected to the bus 21.
It is connected to the CPLI 22 via the CPU 22, and can perform predetermined functions in response to commands from the CPU 22. The output port 20d has three output signal lines, and the first output signal line 31a is connected to the driver 20c and supplies a drive select enable signal. The drive select enable signal controls driver 20c to control whether the drive select O signal and drive select 1 signal are supplied to the respective floppy disk drives 26a and 26b. Output port 20
A second output signal line 31b extending from b is connected to the floppy disk device 26a and supplies a first head load signal. Further, the output port 20b receives the third output signal I
I! 31C, which is connected to the floppy disk drive 26b and provides a second head load signal (in this embodiment, the motor-on signal). As a matter of course, the output port 20d supplies each signal to each device via these three output signal lines under the control of the CPU 22 and the like.

Although only the drive select signal, motor on signal, and drive select enable signal are shown in Figure 3, in a floppy disk system like the one shown in Figure 3, other signals are required to perform the required functions. Interface signals are also used. Therefore, the interface signals and their functions used in a floppy disk system such as that shown in FIG. 3 will be briefly described below.

tzy Ho-Nito' No. 1 - Controls the position of the read/write head, and typically brings the head into contact with the disk at a low level.

Drive select signal: A signal that selectively drives one floppy disk device in a system in which a plurality of floppy disk devices are connected in a daisy chain. When only drive select N (N=0.1.2.3) is set to a low level, the floppy disk device corresponding to that number is selectively driven. Therefore, in the embodiment of FIG. 3, when the drive select O goes low, the floppy disk device 2.6a is put into the driving state, while when the drive select 1 signal goes low, the floppy disk device 26b goes into the driving state. It is said that

Index signal A signal that generates one pulse every time the floppy disk rotates, and the falling edge of that pulse indicates the start of a track.

Motor-on signal This is a signal that controls the driving state of the motor of each float-to-bee disk device, and normally, when the level is low, the motor is driven to rotate.

Direction signal A signal indicating the direction of movement of the head, and is usually at a low level when moving inward, and at a high level when moving outward.

Step signal A signal used to control the movement of the head. Usually, after the direction is instructed by the direction signal, when this step signal becomes low level, the head starts moving. Note that normally, one pulse moves one track.

Write gate signal A signal used for write control, and usually indicates a write-enabled state by going low.

Write data signal A signal used to control data writing. Normally, when the write gate is at a low level, data is written onto the floppy disk by applying a pulse train to this input signal. It will be done.

Track OO signal This is a signal used to detect the track position, and is normally at a low level when the read/write head is at the track OO position.

Write protect signal A signal used to inhibit writing when necessary, and becomes low level when a disk with a write-protection notch is installed, inhibiting writing by the head. .

Read data signal A signal that transfers data read from a floppy disk, and is output in the same format as the write data signal.

Side O signal A signal indicating which side is used on a double-sided floppy disk.

1i-<-'@@ This is a signal indicating that the preparation for reading/writing is completed, and the ready signal becomes true when the three conditions of the normal method are satisfied, indicating the completion of the preparation. That is, (
1) It has been detected that A, C, and DC voltages are being supplied, (2) that the disk is correctly installed, and (3) that the disk has rotated and a predetermined number of index pulses have been generated.

In the embodiment shown in FIG. 3, a normal head load signal is used as the first head load signal, which is used to control the load/unload state of the head of the floppy disk device 26a. On the other hand, the motor-on signal is used as a second head load signal, and is supplied to the second floppy disk 1if26b via the output signal line 31c from the output port t-20b, and is used to load the head in the floppy disk device 26b. - Used to control unload status. By the way, the bus 25 connecting the floppy disk devices fi 26a and 26b to the floppy disk controller 20 is normally
Connected by a single 4-core flat cable.

In the embodiment of FIG. 3, the drive select signal not only functions as a selection signal for selectively activating each floppy disk drive @26a and 26b, but also serves as a selection signal for selectively activating each floppy disk drive @26a and 26b. It also functions as a motor-on signal that controls the driving state of the motor.

Therefore, when these drive select signals are low enable signals, when each drive select signal is set to a low level, the corresponding floppy disk device is selectively driven, and its motor is also driven. Let it be. On the other hand, the so-called motor-on signal supplied to the tray 3 output signal line 31C of the output port 20d is the second
/\If the second head load signal is used as a low enable signal and it is a low level state, the floppy disk 'a' position 26
1] is placed in a loaded state. The first head load signal supplied to the floppy disk device 26a via the second output signal line 31b of the output port 2Od is a so-called head load signal, and therefore, depending on the state of the signal, the load/load of the head in the floppy disk device 26a is determined. Control unload state.

The drive select O signal and the drive select 1 signal are supplied from the floppy disk controller LSI 20a via the driver 20c, and the driver 20c is connected to the output port 20 under control from the CPU 22.
The valid and invalid states of the drive select O signal and the drive select 1 signal are determined by the state of the drive select enable signal supplied through the first output signal line 3'la of the drive select O signal and the drive select 1 signal. That is, when the drive select enable signal supplied from the output port 20d under the control of the CPtJ 22 indicates a prohibited state, the drive select signal is supplied to each of the floppy disk devices 26a and 26b via the driver 20c. There is nothing to do. As mentioned above, the output port 20d outputs the first head load signal and the second head load signal (under the control of the CPU 22).
motor on signal) to each floppy disk device @26
a and 26b. Thus, according to the present invention,
The loading/unloading status of each head of the pair of floppy disk devices 26a and 26b is individually checked by the CPU 2.
It can be controlled by commands from 2. Therefore, for example, the floppy disk drive fff26a
When copying a floppy disk from track to track from the floppy disk drive 26b, even if the operating states of the floppy disk drives are alternately changed over a short period of time, the head of each floppy disk drive must be continuously operated. It is possible to maintain the load state, and therefore it is possible to prevent the generation of noise and vibration that may occur at that time.

On the other hand, when using only a specific floppy disk drive that is open for a long time, it is possible to keep the head in an unloaded state by leaving the other floppy disk drives in a non-driving state, thus reducing wear on the floppy disk. It is possible to prevent this to the maximum extent possible.

In the embodiment shown in FIG. 3, a drive select enable signal is used, so if, for example, all floppy disk drives are not used at all, by turning off this drive select enable signal, all floppy disk drives can be switched off. It is possible to deselect a floppy disk device. Therefore, since the floppy disk drive is set to the non-selected state in this way, the motors of all the floppy disk drives are stopped, and it is therefore possible to expect the life of the motors to be extended. This drive select enable signal is turned on before using any floppy disk device, and if there is no plan to use the floppy disk device again after a predetermined period of time has elapsed after the floppy disk device is used. It is said to be in the OFF state. Incidentally, the operation of the floppy disk system shown in FIG. 3 is shown in a flowchart in FIG.

Effects As described in detail above, according to the floppy disk control device of the present invention, when a plurality of floppy disk devices are connected, it is possible to individually control the ON state of the head of each floppy disk device. Therefore, it is possible to prevent noise and vibration from occurring in the floppy disk device even under certain usage conditions. Further, in the present invention, by using the drive select enable signal, when none of the plurality of floppy disk devices connected to the floppy disk system is used, all of them are set to a non-selected state. Therefore, it is possible to keep all the motors in a non-driving state, and it is possible to expect a longer lifespan of the motors and, in turn, a longer lifespan of the floppy disk device itself.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing the entire floppy disk system, Fig. M2a and Fig. 2b show the state of the head mechanism of the floppy disk device, and Fig. 2a is an explanatory diagram showing the helad unloading state. FIG. 2b is an explanatory diagram showing a head loaded state, FIG. 3 is a block diagram showing one embodiment of the present invention, and FIG. 4 is a flowchart useful for explaining the operation of FIG. 3. . (Explanation of symbols) 20: Floppy disk control device 20a: 5I for floppy disk controller 20b = Data separator 20C: Driver 20d: Output port 22: Central processing unit (CPLI) 26: Floppy disk device (drive) Patent applicant Co., Ltd. Rico -

Claims (1)

[Claims] 1. In a floppy disk control device interposed between a central processing unit and an appropriate number of floppy disk devices, writing and reading of data in the floppy disk devices is performed under the control of the central processing unit. a write/read control means for controlling the floppy disk device; and a drive selection signal enable signal for controlling supply of a drive selection signal from the control means to the floppy disk device for selectively putting the floppy disk device into a driving state. A floppy disk control device comprising: an output port for outputting an equal number of head load signals to be supplied to each of the floppy disk devices under 1ilJfll of the central processing unit.