Data security device

Claim 2

Arrangement according to claim 1, characterized in that the release signal is produced and supplied to the circuit arrangement from the computer with the aid of a program recorded in the fixed store (4) preferably after input of a pass word.

Claim 3

Arrngement according to claim 1, characterized in that furthermore an inhibit signal is preset, which inhibits access to the movable data carrier.

Claim 4

Arrangement according to claim 1, characterized in that different signals are provided for the inhibition or release of write and read access.

Claim 5

Arrangement according to claim 1, characterized in that furthermore network voltage may be supplied to the circuit arrangement (9) over the bus (7, 2).

Claim 6

Arrangement according to claim 5, characterized in that there are provided as outputs switches for one or more of the conductors "read data", "write protection", "selection page 1", and "disk change".

Claim 7

Arrangement according to claim 6, characterized in that there are provided for a computer with a Shugart bus switches for connecting one or more of the connections 28, 30, 32 and 34 with earth potential.

Claim 8

Arrangement according to claim 7, characterized in that furthermore a release and/or inhibit signal is transmissible over the connection 10.

Claim 9

Arrangement according to claim 8, characterized in that the voltage supply of the circuit arrangement (9) takes place over the connection 8 or over the connections 8 and 28.

Claim 10

Arrangement according to claim 2, characterized in that the program for the production of the release signal can be called by input of the program name with the pass word as a parameter.

Claim 11

Arrangement according to claim 10, characterized in that with a preset number of inputs of the program name with a wrong pass word a further call of the program together with the pass word is prevented.

Claim 12

Arrangement according to claim 1, characterized in that a store for a code word is provided in the circuit arrangement.

Claim 13

Arrangement according to claim 10, characterized in that means are provided in the program for the listing of the last pass word entry at any one time and/or a manipulation of the program.

Claim 14

Arrangement according to claim 10, characterized in that means are provided in the program which render the program inoperative after a manipulation of the program.

Claim 15

Arrangement according to claim 10, characterized in that an acoustic report is provided in the program when a wrong pass word is entered or when the program is being manipulated.

Claim 16

Arrangement according to claim 1, characterized in that the controllable circuit arrangement (61) is disposed on a control card (5) which is provided for the control of the write and/or read device.

Claim 17

Arrangement according to claim 16, characterized in that the controllable circuit arrangement (61) is disposed in a control circuit in the form of an integrated circuit (controller).

Claim 18

Arrangement for the protection of data from unauthorised access for a computer with at least one fixed store with a write and/or read device (drive) for a movable data carrier and with a bus connecting the computer and the write and/or read device, characterized in that - a circuit arrangement (71) is provided as a separate modular unit and comprises in known manner a decoder (11, 12, 13) for a release signal supplied at an input, a store (14; 18, 19, 20) for the output signal of the decoder and at least one switch (15; 21, 22, 23) connected to an output, preferably a semiconductor switch, which is controllable from the srored output signal of the decoder, - means are provided for the connection of the input with a conductor (S10) of the bus (7,2) for the supply of the release signal from the computer and - means are provided for the connection of the output with a conductor (74) between the computer and the fixed store (4) which conducts a signal for the switching of the fixed store (4) to write operation.

Claim 19

Arrangement according to claim 5, characterized in that at least one connection of the circuit arrangement (9, 61) for the operating voltage is connectable with a conductor (S8, S28) of the bus (7, 2) and that the connection is connected to a condenser (17) over a diode (16, 24).

Claim 20

Arrangement according to claim 19, characterized in that several connections are each connectable with one conductor (S8, S28) of the bus (7, 2) and in that the connections are each connected with a condenser (17) over a diode (16, 24) each.