DE19606663A1 - Locking device for disk drive protection - Google Patents

Abstract

The apparatus has the diskette mechanism (35) connected with the controller (36) of a computer via a flat ribbon cable (37). The cable has many conductive lines (1 to 34), of which a control line (28) of the mechanism, is connected with the write protecting switch, and the line number 30 transmits the read data. The lines 27 and 29 are earthing lines, while the lines 27 and 28 and the lines 29 and 30, respectively, are individually connected together through a double pole switch (38). The line 30 and the line 28 can be connected to the earthing lines by this switching arrangement, If the control lines (28,29) and the earth line are connected through the switch (38), a diskette in the drive cannot be used for recording or reading data. The computer will inform the user of this condition..

Description

The invention relates to a backup for a floppy disk drive, especially to protect against unwanted Access to data on the diskette and / or one via the Floppy drive tapable hard disk space from a computer.

Conventional floppy drives have among others for their functions, such as drive motor, Stepper motor and control electronics, two combined Read / write heads on. These are for the transfer of Read / write data via lines with the controller of the Computer connected to the individual components of the Computer system controls. The floppy drives are included a write protection switch equipped by a inserted floppy disk can be operated predetermined. Pressing the write protection switch turns on Ground connection established, the transfer of data on the disk is disabled. The disadvantage is that the Floppy drives have an unprotected interface between a computer's hard drive and the outside world represent, so that every unauthorized user Copy data unhindered or view the installed data Programs can take control.

External closure devices are already on the market available, but which have the disadvantage that with their Actuation the drive is completely locked.

The invention has for its object a backup for a floppy disk drive in the preamble of claim 1 Specify the type mentioned, with which optionally beforehand  can be determined whether the user is unimpeded, i. H. can normally access the floppy disk drive or whether it should only be able to read floppy disks if, for example Customer disks - e.g. B. common with DTP users - read must be, or whether in another case the floppy disk drive should be locked completely if that Drive only needed to install programs and the computer is then only used as a workstation should serve.

The task is performed on a floppy disk drive after Preamble of claim 1 by its characterizing Features resolved. Predefined lines, especially the Line connected to the write protection switch in the Floppy disk drive is connected and / or the line that Read data is transmitted via switching means with the Ground wire connected, causing the transfer of Signals is prevented. This can be done in advance set whether the user is normal to the drive can access whether he can only read floppy disks, or but whether the floppy drive will be completely locked should. The fuse can be installed with minimal effort and protects the floppy drive as an interface reliable against unwanted access. she is easy to use and uncomplicated.

For example, the floppy disk drive can use a Special key operated key switch with on Continuity or interruption of switchable relay contacts assigned to the control lines between the Floppy drive and the controller of the computer are switched.

An embodiment essential to the invention provides that the Key switch three switch positions "LS", "L" and "0" has, the position "L" the line, which with the Write protection switch in the floppy disk drive is connected, shorts to the ground line, such that the floppy disk  cannot be described. In the switch position "0" the key switch closes the line connected to the Write protect switch in the floppy disk drive is connected and at the same time the one intended for the transmission of read data Short with the respective ground line, so that the Diskette can neither be written nor read.

And finally, according to the invention, the fuse provides that in the "LS" position of the switch, the short-circuit scarf open to the ground and the floppy disk drive is released.

According to a further embodiment, the floppy disk drive arranged in a mounting frame in which the key switch and the lines from this to the floppy disk drive are accommodated. As a result, the invention Device like a ordinary floppy disk drive from anyone who has PC knowledge, can be easily installed. Ins special is the installation with a conventional floppy disk drive absolutely identical. It goes without saying factory standard equipment of floppy disks given drives with the fuse according to the invention.

In the following the invention with reference to drawings explained in more detail.

Show it:

Fig. 1 is a diagram of the wiring connections between a floppy disk drive and the controller of a computer with an inventive fuse,

Fig. 2 shows a key switch as switching means with three switching stages,

Fig. 3 is a front view of a mounting frame with the floppy disk drive and the key switch and

Fig. 4 is a plan view of the mounting frame, schematically.

In Fig. 1, the connection of a floppy disk drive ( 35 ) with the controller ( 36 ) of a computer is shown schematically, which is given via a ribbon cable ( 37 ). Lines 1 to 34 are arranged in the ribbon cable ( 37 ), of which line ( 28 ) is connected as a control line in floppy disk drive ( 35 ) to a write protection switch (not shown) and line ( 30 ) transmits read data as control line. The lines ( 27 and 29 ) are ground lines. The lines ( 27 and 28 ) and the lines ( 29 and 30 ) can each be connected to one another via switching means ( 38 ), that is to say the line ( 30 ) transmitting the read data to the ground line ( 29 ) and the line connected to the write protection switch (not shown) ( 28 ) with the ground line ( 27 ). If the respective control line ( 28 , 29 ) and the ground line are connected by the switching means ( 38 ), a floppy disk located in the floppy disk drive ( 35 ) cannot be written or read. The computer issues a corresponding message to the user.

In FIG. 2, a composite used as switching means (38) key switch (38) is shown. It has two mutually independent contact rows, each with two movable switch contacts ( 39 and 40 ). The zero position of the key switch ( 38 ) is shown, which corresponds to the switch position "L", in which the contact ( 39 ) is closed and the diskette cannot be written to. In the left key position (corresponds to the "LS" position) the upper row of contacts is switched and the contact ( 39 ) is opened. Thus both contacts ( 39 and 40 ) are open, the floppy disk drive is released ( Fig. 1).

At the transition from the key position "L" to the key position "0", the lower row of contacts is actuated, the upper row maintaining its position, and the contact ( 40 ) is closed, so that both contacts ( 39 and 40 ) are now closed and the Diskette can neither be written nor read.

Fig. 3 shows the disposed in a mounting frame (39) adjacent to the floppy disk drive (35) key switch (38) with the switching positions "0", "L" and "LS", Fig. 4, the connection of the key switch with the connector (41) for the ribbon cable ( 37 ) on the floppy disk drive ( 35 ), the lines to the key switch ( 38 ) being coupled to the corresponding soldering points of the plug ( 41 ) on the printed circuit board (not shown).

Claims (6)

1. Backup for a floppy disk drive, in particular for protection against undesired access to data on a floppy disk and / or a hard disk memory of a computer which can be tapped via the floppy disk drive and which is connected to a controller of the computer via control lines, characterized in that predetermined lines, in particular the Line ( 28 ), which is connected to the write protection switch in the floppy disk drive ( 35 ), and the line ( 30 ), which transmits read data, can be connected to the respective ground line ( 27 ; 29 ) by switching means ( 38 ). 2. Fuse according to claim 1, characterized in that as switching means ( 38 ) the floppy disk drive ( 35 ) is assigned a key switch which can be actuated by means of a special key with contacts ( 39 , 40 ) which can be switched to pass or break and which are connected between the control lines ( 28 ; 30 ) and the corresponding ground lines ( 27 ; 29 ) are arranged between the floppy disk drive ( 35 ) and the controller ( 36 ) of the computer. 3. Fuse according to claim 1, characterized in that the key switch ( 38 ) in the "0" position shorts the line ( 28 ) and at the same time the line ( 30 ) provided for the transmission of read data with the respective ground line ( 27 ; 29 ), so that the diskette cannot be written and read. 4. Fuse according to claim 1, characterized in that in the "LS" position of the key switch ( 38 ) the short-circuit circuits ( 28 , 30 ) to ground ( 27 , 29 ) are open and the floppy disk drive ( 35 ) is released. 5. Fuse according to claim 1, characterized in that the floppy disk drive ( 35 ) is arranged in a mounting frame ( 39 ) in which the key switch ( 38 ) and the lines from this to the floppy disk drive ( 35 ) are housed. 6. Fuse according to claim 1, characterized in that in the "L" position of the key switch ( 38 ) the short circuit between the control line ( 28 ) and the ground ( 27 ) is closed and the diskette cannot be written to, but can only be read .