SU1510004A2 - Device for marking and search for information on carrier - Google Patents

Abstract

The invention relates to magnetic recording, namely, devices for marking and searching information on a tape medium. The invention makes it possible to increase the reliability of a search in case of a failure of a reproduced signal and provides a search for a distorted zone address. By comparing the four consecutive values of the reproduced zone addresses (assuming that they differ by one) among themselves, a reliable value of the zone address is determined. This code phases the operation of the reversible counter 17, which counts the signals from the speed sensor of the recording-playback unit 4. Thus, in the event of a distortion of the zone address on the reversible counter, the address will be restored. 1 il.

Description

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The invention relates to magnetic recording, in particular, devices for marking and searching information on a tape carrier, and is an improvement of the device according to the main author. N 1108500.

The purpose of the invention is to increase the reliability in operation when the reproduced signal fails.

The drawing shows a block diagram of the device.

The device comprises a coordinate input unit 1, a comparison unit 2, a control unit 3, a recording-reproduction unit 4, a marker signal firing unit 5, a block subtraction unit 6, a sign analysis unit 7, a difference sensor 8, the first register 9, the second register 10, the third register 11, fourth quad of register 12, first arithmetic unit / (AU) 13, second AU 14, third AU 15, comparison circuit 16, reversible counter 17.

The device works as follows.

In the recording mode in block 5 of the formation of marker signals, the zone address codes (tape marking codes) are generated from the initial zero value by the installation signal from control block 3 and the marking codes are written to the media. Depending on the information recording density, by a command from the control unit 3, in the difference sensor 8, a difference code value corresponding to a given recording density is formed. Before starting the search for information from the control unit 3, the number corresponding to the value of the inertial run of the recording medium is entered into the unit 5 for the formation of marker signals. In block 1 of entering coordinates, a code is set up for the required section of the recording medium.

When playing in block 5 of the formation of marker signals, markup codes are allocated from the recording medium, the selected codes are successively entered into shift registers 9-12. As when writing, each subsequent value of the code. markup is formed from the previous one by adding one, then the reproduced code can be considered reliable enough with sufficiently high accuracy, if the four following each

the other meaning of the markup codes differ from each other by one. A value of four is selected based on

experiment as the most optimal. Therefore, in arithmetic devices 13-15, addition is performed (if the tape moves in the forward direction) or. Subtraction (if the ribbon moves in the opposite direction) at the command from the control unit 3 from the values of the marking codes, respectively, of numbers 1, 2, 3, m. e. the codes are of the same type and, when compared, their comparison circuit 16 generates an equality signal, which indicates that a valid markup code is being reproduced from the recording medium. Numbers 1, 2,3 are set and

0 from control block 3. A valid code from the output of register 9 is entered into the reversible counter 17 by the equality signal from the comparison circuit 16. In case of a replay

5 signals to registers 9-12 comes a distorted markup code. The registers differ from each other by an amount different from one, and the scheme. 16 comparisons gives a signal

0 inequality, which prohibits the phase of the reversible counter 17 by the reproduced markup code. Counter 17 recovers the missing signals using sensor signals

5, the speed of the recording-reproducing node 4 is phased by the next valid value of the reproduced markup code.

Reverse Counter State

0 17 is constantly compared with the code entered in the coordinate input block 1, in the subtraction block 6 and the sign analysis block 7. The sign analysis unit 7 forms the corresponding signal in

5, the control unit 3, thereby setting forward or reverse movement of the recording medium. Depending on this, the control unit 3 issues counting commands for the reversible counter 17, adding or subtracting for the AU 13-15 and the direction of movement for the recording-playback unit 4 . The current difference from the subtraction unit 4 is compared with its predetermined value received from the difference sensor, and depending on this, the control unit 3 issues a speed command to the recording-playback unit 4. If the difference value is more than 515

If the specified value is exceeded, then the search is performed at the maximum speed. When the current difference decreases, the comparison unit 2 generates a signal by which the control unit 3 reduces the speed of movement of the carrier to the minimum value in the recording-playback unit 4. At the moment of equality of the codes from the coordinate input unit 1 and the reversible counter 17, the control unit 3 generates a signal for setting the recording-playback unit 4 and the reversing counter 17

Thus, the proposed device eliminates the effect of failures in the reproduced signal on the search for information, restores the distorted tape marking codes, which ensures the search for sections with a distorted zone address.

Claims (1)

Invention Formula A device for marking and searching information on a recording medium according to avt.S. No. 1108500, characterized in that, in order to improve reliability in operation when a reproduced signal fails, three arithmetic are added to it 0004 ( device, comparison circuit, reversible counter and four successively connected shift registers, the group of outputs of the first of which is connected to the first group of inputs of the comparison scheme, and groups I of the outputs of the other registers are connected to the first groups of inputs of the first, second and third arithmetic devices respectively, the output groups of the arithmetic devices are connected to the corresponding input groups of the comparison circuit, 15 second inputs of the arithmetic devices are connected respectively to the fourth, right, and estomu outputs of the control unit and the third input - to the seventh output control unit, wherein the reversible counter 20 is connected to the output from the first subtracting unit and the input analysis unit sign, the first input - with the output of the comparison circuit, the second input - to yield 25 recording-playback node, with the third input - with the eighth step of the control unit, and a group of inputs - with the output group of the first register, whose input is connected to the second OQ output of the block of formation of marker signals that i - Compiled by S. Podorsky. . Editor A. Motyl Tehred A. Kravchuk Proofreader T. Kolb Order 5822/52. Circulation 558 VNISh of the State Committee on Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk on 4/5 Subscription