SU1099324A1 - Device for reproducing digital information signals from magnetic medium - Google Patents

Abstract

DIGITAL SIGNAL REPRODUCING APPARATUS information from magnetic media, comprising power-generator, a first group of two D -triggerov, output data bus and bus clock pulses, an inertial generator connected to the clock input of the first D -triggera first group, an information input of which is connected to the output The second D-trigger of the first group, and the output of the first D-flip-flop is connected to the output information bus, characterized in that, in order to increase the fidelity of reproduction, delay element, controllable delay unit, pulse distributor, delay codes memory block, second D-flip-flop group and OR element, the output of the amplifier-former is connected to the inertial generator input and the D-trigger synchronization inputs of the second group, the output of the inertial generator is connected bus synchronization pulses and through the delay element - with the input of the controllable delay block, the output of this block is connected to the input of the pulse distributor and the clock input of the second D-flip-flop of the first group, Each output of the pulse distributor is connected to one of the address inputs of the memory block of the delay codes and the information input of one of the D triggers of the second group, while the reset input of each previous D trigger of the second group (L is connected to the information input of the next D trigger of this group, and the reset input of the last D-flip-flop of the second group is connected to the information input of the first D-flip-flop of the second group, the outputs of all D-flip-flops of the second group are connected with co with to the inputs of the OR element, the output of which is connected with the information input of the second D trigger of the first group, and the outputs of the memory block of the delay codes are connected to the address inputs of the block 0 of the controlled delay. J

Description

110 The invention relates to magnetic recording and computing techniques and can be used in memory devices on moving magnetic media. A device for reproducing signals of digital information from a magnetic carrier is known, which contains an inertial generator, a counting trigger. time warp corrector

The first of the two channels connected to the output OR circuit, made in the form of the first AND circuit, a trigger and the OR circuit, one input of which is connected to the output of the second AND circuit, and a pulse separator. The device provides reproduction of signals recorded on magnetic media using the modified phase modulation method L.

The disadvantage of this device lies in the lack of universality, since it does not provide reproduction of signals encoded with another code or recorded on magnetic media in another way.

The closest in technical essence to the present invention is a device for reproducing signals of digital information from a magnetic carrier, comprising a series-connected amplifier-shaper, a phase detector, a filter; inertial generator, first and second monostable multivibrators, three D-flip-flops, the driver amplifier output is additionally connected to the first D-TpHfrepa synchronous input, the second output of the inertia generator is connected to the second input of the phase detector, the input of the first monostable multivibrator is connected to the bus of the phase inductors of the phase detector, connected to the second input of the phase detector, to the second monostable multivibrator, connected to the bus of the phase detector, connected to the second input of the phase detector, to the second monostable multivibrator, connected to the second bus of the phase detector; the synchronous input of the second D-flip-flop, the output of the second monostable multivibrator is connected to the reset input of the first D-flip-flop and to the synchronous input of the third D-flip-flop, the inverse output of the first D- the trigger is connected to the information input of the third D-flip-flop, the direct output of which is connected to the ion input of the second D-flip-flop, the direct output of the second D-flip-flop is connected to the output information 2 bus.

The disadvantage of this device is that it can only be used in storage devices on the maggo carrier, which contains an amplifier-former, an inertial generator, the first group of two D-flip-flops, an output information bus and a synchronization pulse bus, an inertial generator connected to the synchronization input of the first D -trigger of the first group, the information input of which is connected to the output of the second D-flip-flop of the first group, and the output of the first D-flip-flop is connected to the output information bus, a delay element, block y is entered equal delay, pulse distributor, memory of delay codes, second group of D-flip-flops and an OR element, the output of the amplifier-former is connected to the input of the inertial generator and the clock inputs of the second flip-flops, the output of the inertial generator is connected to the bus of synchronization pulses and through the delay element - with the input of the controllable delay block, the output of this block is connected to the input of the pulse distributor and the clock input of the second D-flip-flop of the first group, each output of the distributor the pulses are connected to one of the address inputs of the memory of the delay codes and the information input of one of the D-flip-flops of the second group, and the reset input of each previous D-flip-flop of the second group is connected to the information input of each subsequent O-flip-flop of this group, and the reset input of the last The D-flip-flop of the second group is connected to the information input of the first D-flip-flop of the second group, the outputs of all D-flip-flops of the second group are connected to the inputs of the OR element, the output of which is connected to the information input of the second D-flip-flop rvoy group, and outputs the delay memory code block unit coupled to address inputs of a controllable delay.

Introduction to a digital information reproduction device of a 24nit carrier, information in which is recorded by a modified phase modulation (IMF) method in view of a limitation on recording density with significant phase distortions, i The purpose of the invention is to increase the fidelity of the reproduction. This goal is achieved by the fact that the proposed device can be applied to a device for reproducing digital information from a magnetic carrier of a delay element, a controllable delay unit, a pulse distributor, a memory of delay codes, an OR element, and a second group of D-flip-flops. in magnetic magnetic disk storage systems in which information is encoded by any self-synchronizing code with a constant word length and the recording is carried out using the BVIM method, which consists in changing the direction ka records for each unit or zero input digital information. Fig, 1 shows the structural diagram of the proposed device; in fig. 2 - time diagrams that show his work. The device for reproducing digital information signals from a magnetic carrier contains amplifier-generator 1, inertial generator 2, delay element 3, controllable delay unit 4, impulse distributor 5, delay code memory block 6, D-flip-flops 7-9 of the second group, the element OR 10, two D-flip-flops 11 and 12. of the first group, the output information bus 13 and the synchronization pulse bus 14. Amplifier-shaper 1 is designed to amplify signals of digital information reproduced from a magnetic carrier and to form rectangular pulses on them. Inertia generator 2 is designed to generate a series of pulses with a stable frequency, according to the average phase and frequency of the pulses arriving at its input from the output of the amplifier of the former 1. Element 3 delays delay a series of pulses arriving at its input from the output of the inertial generator 2 Controllable delay unit 4 is a digital control delay line that is designed to delay the time of each pulse arriving at its information input from the output of delay element 3. The delay value determines the combination of signals at the control inputs of control delay unit 4. From the output of block 4 of the controlled delay, pulses are fed to the input to distribute 5 pulses, which is an annular shift register, in one of whose bits a unit is written. The pulse distributor 5 is designed to form waiting intervals for the reproduced digital information signals and to generate code combinations at the outputs. The delay code memory unit 6 is designed to store N constant codes corresponding in advance known for this method of encoding the probability density of the reproduced signals. The address inputs of the block 6 of the memory of the delay codes are connected to the corresponding outputs of the distributor 5 pulses, and the outputs are connected to the control inputs of the block 4 of the controlled delay. D-triggers 7, 8, 9, 11, 12 and the element OR 10 are designed to separate the signals reproduced from the magnetic carrier and bind them to the output clock pulses. The synchronization inputs of the D-flip-flops 7-9 are connected to the output of the amplifier-former 1, the information input of the D-flip-flop 7 and the reset input of the D-flip-flop 9 are connected to the first output of the distributor 5 pulses, the reset input of the D-flip-flop 7 and the information input of the D-flip-flop 8 connected to the second output of the distributor 5 pulses, the reset input of the D-flip-flop 8 and the information input of the D-flip-flop 9 are connected to the third output of the distributor 5 of the pulses. The outputs of the D-flip-flops 7-9 are connected to the inputs of the element OR 10, the output of which is connected to the information input of the D-flip-flop 11. The synchronizing input of the D-flip-flop 11 is connected to the input of the ring shifter 5, and the output of the D.-flip-flop 11 is connected to the information input D-flip-flop 12. The output of the D-flip-flop 12 is connected to the output information bus 13. Synchronized input D-flip-flop 12, is connected to the output of the inertial generator 2 and the bus 14 pulse synchronization. The device works as follows. The coded digital information recorded on magnetic media (Fig. 2a) is reproduced with phase distortions caused by the mutual influence of the reproduced signals, which, for example, are equal to it, it2 and At. (Fig. 2b). According to the peaks of the reproduced signals (Fig. 26), the Usi-Soul-Former 1 generates pulses (Fig. 2c), in the middle phase and frequency of which the inertial generator 2 produces a series of pulses (Fig. 2d) of a stable frequency. Then this series of pulses is delayed by a delay element 3 at a value of 0.5 T (Fig. 2d), where X is the period of the pulses generated by the inertial generator 2, and is fed to the input of an adjustable delay unit 4, in which a time delay occurs each pulse (Fig. 2g, the delay value is bi5 and ut 6). The delay value is set by the code combination received at the address inputs of the controlled delay unit 4 from the outputs of the delay codes memory block 6. The code pattern at the output of memory block 6 of the delay code varies for each pulse received from the output of control block 4 to the input of the distributor 5 pulses (Figure 2d), where the output combination to the address-inputs of memory block 6 is changed delay codes. Thus, each previous pulse arriving at the input of the control delay unit 4 sets the value of the delay of the next pulse. The number of cells in block 6 of the memory of the code of the delay is generally equal to the number of characters in each coded group (three cells are used in the example) .. The cells contain codes known in advance for this recording method (code) of the probability probability density of the reproduced signal (Fig. 2e), setting such delay values of the pulses arriving at the input of the control unit 4 of the delay to combine their fronts with the moments of equality of the densities of probabilities of displacement of two adjacent playback signals I ( . 2e, f). The pulse delay operation in block 4 of the controlled delay allows the output of the pulse distributor to generate 5 pulses optimal for this method of recording the sleep interval signals (Fig. 2h) and which are fed to the information inputs of the D-flip-flops 7-9 of the second group. When a playback signal arrives at the synchronization inputs of D-flip-flops 7-9 (Fig. 2c), that trigger 4 is set at one input at whose information input the sleep interval signal is active. The next sleep interval signal is reset. the cocked trigger is in the zero state (fig. 2z, and, k, l). At the output of the element OR 10 (fig. 2l), a series of reproduced signals is formed which are uneven in duration and randomly spaced in time. This series of signals enters To the information input of the second D-flip-flop 11 of the first group, to the synchronization input of which pulses are given with an uneven tracking frequency (Fig. 2g). A series of signals from the output of the D-flip-flop 11 is fed to the information input of the D-flip-flop 12 of the first group, to the sync input which Serial enters Pulses from the output of the inertial generator 2 (FIG. 2d). From the output of the D-flip-flop 12, the playback information signals (Fig. 2n) are received into the output information bus 13 (Fig. 2n), corresponding to the signals recorded on the digital information carrier. The introduction of digital information from a magnetic carrier of a delay element, a controllable delay block, a pulse distributor, a block of memory of delay codes, an OR element, and a group of D-flip-flops to a device for reproducing signals advantageously distinguishes it from the basic device for reproducing digital information signals from a magnetic carrier used in the system of an EU 5080 magnetic disk drive, since the proposed device makes it possible to reproduce digital information signals encoded by any self-synchronizing device. th. The separation of reproduced signals is based on their statistical characteristics, namely, the probability density of the reproduced signals depending on the selected record code, which reduces the likelihood of error when playing digital information signals with significant phase distortion. The application of the proposed device in a magnetic storage system allows you to reproduce the data presented in the code with increased information content, i.e. if instead of code modified

phase modulation, information content of data transfer to magnetic media

which is 2 bits / period, apply ln / 25% and thereby increase the inforcode 2.7 with the information content of 3 bits / storage capacity of the drive, which

If the period, then without increasing the size, but it provides higher technical media, you can increase the density of economic indicators.

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Claims (1)

DEVICE FOR PLAYING DIGITAL INFORMATION SIGNALS FROM A MAGNETIC MEDIA, comprising a driver amplifier, a first group of two D triggers, an output information bus and a synchronization pulse bus, an inertial generator connected to the synchronizing input of the first D trigger of the first group, the information the second D-trigger of the first group, and the output of the first D-trigger is connected to the output information bus, characterized in that, in order to increase fidelity of reproduction, an element is inserted into it delays, controlled delay unit, pulse distributor, delay code memory block, the second group of D-flip-flops and the OR element, while the output of the amplifier-former is connected to the input of the inertial generator and the synchronizing inputs of the D-triggers of the second group, the output of the inertial generator is connected to the synchronization pulse bus and through the delay element - with the input of the controlled delay unit, the output of this unit is connected to the input of the pulse distributor and the synchronizing input of the second D-trigger of the first group, each output is distributed The pulse distributor is connected to one of the address inputs of the delay code memory block and the information input of one of the D-triggers of the second group, while the reset input of each g of the previous D-trigger of the second group is connected to the information input of each subsequent D-trigger of this group, and the reset input the last D-trigger of the second group is connected to the information input of the first D-trigger of the second group, the outputs of all D-triggers of the second group are connected to the inputs of the OR element, the output of which is connected to the information input of the second D - rigger first group, and outputs the delay memory block codes connected with the address inputs of controllable delay unit. SU .... 1099324>