JPS6348656A - Flexible disk drive - Google Patents

Abstract

PURPOSE:To prevent the destruction of data recorded on a flexible disk by inhibiting the recording to the flexible disk if the commanded recording density differs from the recording density of the loaded flexible disk. CONSTITUTION:A signal (a) is a recording density command signal for the flexible disk inputted from a host device, its high level indicates the standard recording density and its low level represents a high recording density. A signal (b) is a write gate signal commanding the recording and its low level depicts the recording. A signal (c) is a recording data string to make a changing point at the trailing of a signal effective. A photo transistor (TR) 5 and a light emitting diode 3 are arranged while being opposed to each other with a recording density sensing hole 2 of the flexible disk inbetween, and the state of the recording density sensing hole 2 of the flexible disk is outputted as a signal (d). In this case, since the signals (a, d) are dissident, a signal (e) is at a high level, the signals b, c from the host device are not effective signals and the recording onto the flexible disk is disabled.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to the field of flexible disk drives.

[Conventional technology]

Conventional flexible disk drives that can accommodate flexible disks with a plurality of recording densities perform recording and reproducing operations according to the recording degree instructed by a host device.

[Apex while the invention is about to come to fruition]

However, in the conventional technology described above, recording and playback are performed only at the recording density instructed by the host device, regardless of the recording density of the flexible disk installed in the flexible disk drive, so that normal recording and playback operations cannot be performed. The data recorded on the flexible disk may be destroyed.

Therefore, the present invention aims to solve these problems.
The purpose of this is to detect the recording density of the flexible disk detected by the flexible disk drive's recording density detection mechanism and the recording density that the flexible disk drive's host device instructs to the flexible disk drive via the interface signal. If the densities differ, the problem lies in providing a flexible disk drive having a recording control circuit that prohibits recording operations on the flexible disk mounted in the flexible disk drive. [Means for Solving the Problem] The flexible disk drive of the present invention allows the recording density of the flexible disk detected by the recording density detection mechanism of the flexible disk drive to be detected by the host device of the flexible disk drive via an interface signal. The flexible disk drive is characterized by having a recording control circuit that prohibits a recording operation on the flexible disk mounted in the flexible disk drive when the recording density instructed to the flexible disk drive is different from the recording density instructed to the flexible disk drive. do.

[Effect]

According to the above configuration of the present invention, if the recording density of the flexible disk on which the host device attempts to perform the recording or reproducing operation is different from the recording density of the flexible disk installed in the 7 lexiple disk drive, By prohibiting the recording operation on the flexible disk using the recording system of the flexible disk drive, it is possible to prevent the data recorded on the flexible disk from being destroyed.

〔Example〕

FIG. 1 is a block diagram of a flexible disk drive in an embodiment of the present invention. The signal α is a flexible disk recording density instruction signal inputted from a host device, and a high level indicates a standard recording density, and a low level indicates a high recording density. The signal S is a write gate signal that is input from a host device and instructs a recording operation to a flexible disk, and the recording operation is performed at a low level.

Signal C is a data string to be recorded on a flexible disk that is input from a host device, and the falling transition point of the signal is made valid. 1 is a flexible disk attached to a flexible disk drive.
2 is a recording density detection hole for indicating the recording density of the flexible disk to the flexible disk drive;
An open detection hole indicates that the flexible disk has a high recording density, and a closed detection hole indicates that the flexible disk has a standard recording density. 3 is a light emitting diode, and 4 is a resistor for limiting the current flowing through the light emitting diode. 5 is a phototransistor. A phototransistor 5 and a light emitting diode 3 are placed opposite each other across the recording density detection hole of the flexible disk 2, and output the state of the recording density detection hole of the flexible disk as a signal d. 6 is a pull-up resistor. Signal d and signal a are input to a 7 exclusive OR circuit, the output of which is applied to signal e. If the state of the signal d and the state of the signal α match, the signal C becomes a low level, and if the state of the signal d and the state of the signal α do not match, the signal C becomes a high level. signal d
When the signal α and the signal α match, the signal e becomes high level, and the signal C becomes the AND circuit output signal f, ! of 8.9, respectively. 1 is output. On the other hand, if the signal d and the signal α do not match, the signal e becomes high level and the signal f9g becomes low level regardless of the status of the signals 1 and 2. Since no signal is input to the recording circuit, the recording operation on the flexible disk is not possible. Not done.

Fig. 2 shows the timing chart for the recording operation when the signal α and the signal d in Fig. 1 match, and Fig. 3 shows the timing chart for the recording operation when the signal
1! is a timing chart regarding the recording operation when the signal a and the signal d in FIG. 1 do not match. In FIG. 2, since the signal α and the signal d match, the key word C is at a low level, and the write gate signal from the host device and the recording data string, that is, the key word and the signal C, respectively. This appears in the signal f and the signal j, making it possible to perform a recording operation on the flexible disk. On the other hand, in Fig. 2, the signal α
Since there is a mismatch between signal d and signal d, signal C is at a high level, and when the signal from the host device is sent, signal C does not become a valid word and recording on the flexible disk becomes impossible. ing.

〔Effect of the invention〕

As described above, according to the present invention, when the recording density instructed by the host device to the flexible disk drive differs from the recording density of the flexible disk mounted in the flexible disk drive, the flexible disk A flexible disk attached to a disk drive.
Flexible disk recording operation
By prohibiting this in the drive's recording/playback control circuit, if a computer system operator inserts the wrong flexible disk into a flexible disk drive, the data recorded on the flexible disk can be prevented from being destroyed. It can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of a flexible disk drive of the present invention. 2 and 3 are timing charts of each signal line in FIG. 1. 1...Flexible disc jacket 2
... Recording density opening 3 ... Light emitting diode 5 ... Photo transistor 7 ...
Exclusive power OR circuit 8......AND circuit 9......AND circuit 10...Recording circuit or more 'Puff- ++-j -311・Fig.

Claims (1)

[Claims] A main shaft motor for rotationally driving a flexible disk, a magnetic head for recording and reproducing information on the flexible disk, a carriage for supporting the magnetic head, a positioning mechanism for the magnetic head and the carriage, and a positioning mechanism for the magnetic head and the carriage. A flexible disk consisting of a carriage position control circuit for controlling the carriage position, a recording circuit for recording on the flexible disk, a reproduction circuit for reproducing signals recorded on the flexible disk, and a recording density detection mechanism for the flexible disk.・
In the drive, the recording density of the flexible disk detected by the recording density detection mechanism is different from the recording density instructed by the host device of the flexible disk drive to the flexible disk drive via an interface signal. In some cases, a flexible disk drive is characterized in that it has a recording/playback control circuit that prohibits recording operations on a flexible disk mounted in the flexible disk drive.