SU1024983A1 - Device for testing multichannel magnetic recording apparatus - Google Patents

Abstract

A DEVICE FOR CONSTRUCTING A MULTICHANNEL MAGNETIC RECORDING DEVICE, containing recording current sensors connected to magnetic heads of recording channels, a control unit whose inputs are connected through the first and second multiplexers to the input channels of the recording channel and from the recording current sensor sensors, respectively, the control unit, an input connected to the output of the generator, and outputs connected to the corresponding control inputs of the multiplexers, and an output counter, characterized in that, in order to provide the possibility of a roll of the specified number of channels, a self-blocking counter is inserted in it, connected between the output of the control unit and the information input of the output counter with an additional input of the account module installation, the installation input of which is connected to the additional output of the control unit, and the installation input is self-locking (L counter connected to the output of generator.

Description

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The invention relates to instrumentation, in particular, to recording devices for recording recording, and can be used in multichannel equipment of a digital magnetic recording with redundancy. A device for monitoring a multi-channel magnetic recording apparatus, included in a magnetic recording device and containing recording current sensors (each consisting of an exemplary resistor and two opposite key elements), connected to magnetic heads of recording channels, and a multi-channel control unit ( contains in an amount equal to the number of control “dx recording channels, control circuits, each of which includes a switching capacitor and a rectifier trigger) 1. The drawbacks of this device are that it does not provide high accuracy of monitoring the operation of digital magnetic recording channels and does not allow automatic control of the time of failure of the multichannel magnetic recording apparatus as a whole according to a given failure criterion. Asked by the criterion of the multi-channel apparatus, i.e. a sign on the basis of which it is necessary to automatically make an exact determination of the moment of his refusal is the excess of the number of the indicated channels of that possible number of channels that failed to record information, which is still valid relative to the total number of simultaneously used recording channels of the device without issuing a signal from its failure. It is also known a device for monitoring a multi-channel magnetic recording apparatus, a device for magnetic information recording and containing recording current sensors (assembled on the basis of the OR elements), connected to the magnetic heads of the Recording Channels (each of which includes a coding unit, a switch and two current record drivers), and a multichannel control unit (contains, in a quantity equal to the number of monitored recording channels, control circuits, each of which is derived from the AND element, two blocks; neither f impulses, delay lines, two prohibition elements and the OR element 2. However, such a device does not automatically control the failure of the multichannel magnetic recording apparatus according to a given failure criterion. The device with high accuracy controls the functioning of the channels of the digital magnetic recording separately and at the same time, it signals to the operator channel-by-channel about a malfunction of one or several recording channels of the device. However, this is not enough for the monitoring device to ensure that the backup recording device automatically switches on in time when the main one fails, since a possible failure criterion could be, for example, at least half of the recording channels of a multichannel device failing. Automatic fixation of this situation and others like it In the equipment operated by an operator-free operator, the known device does not provide. The closest in technical essence of the present invention is a device for monitoring recording channels of a magnetic recording apparatus, comprising recording current sensors connected to magnetic heads of recording channels, a control unit whose inputs are connected through first and second multiplexers to inputs of recording channels and to outputs recording current sensors, a control unit, an input connected to the output of the master oscillator (includes the generator itself and a divider), and the outputs connected to the control inputs of the multi lexors, and output counter (includes the pulse shaper X) The device controls the performance of the magnetic recording channels according to the most correct criterion of their failure (failure of a separate channel) according to the reliability of their transmission of digital information, while using a single-channel control unit that alternately connects two inputs } to the input and output of each channel of the recording of the reference. The disadvantage of the known device is that it does not provide the ability to automatically control the moment of failure nogokanalnogo magnetic recording apparatus according to claim, to specify criteria in advance of failure. The known device generates an output signal when one of the recording channels fails, which, for example, when parallel recording digital information is pre-temporal. And set another failure criterion, i.e. To change (increase) the permissible number of failed Channels, the excess of which by the actual number of failed channels is considered a failure of the multichannel device, the known device does not allow.

The aim of the invention is to enable the monitoring of failures of a given number of channels.

The goal is achieved by the fact that in the device containing the recording current sensors,

iK magnetic recording channel heads, a control unit whose inputs are connected through the first and second multiplexers to the inputs of the recording channels and to the outputs of the write current sensors, respectively, the control unit, the input connected to the output of the master oscillator, and the outputs connected to the corresponding control inputs of the multiplexers, and, output counter, a self-blocking counter is inserted, connected between the output of the control unit and the information input of the output counter with an additional input of the installation of the counting module, installation whose input is connected to the auxiliary output of the control unit, and the installation input of the self-locking counter is connected to the output of the master oscillator,

 FIG. 1 shows a functional diagram of the device; in fig. 2 one of the variants of the scheme of the control unit j in FIG. 3 is an example of a specific implementation of a self-blocking counter.

The proposed device for monitoring a multichannel magnetic recording apparatus, each recording channel of which consists of serially connected buses 1 for entering information from recording unit 2 and magnetic recording head, contains recording current sensors 4, first 5 and second 6 multiplexers, control unit 7, self-locking counter 8 weekend

the counter 9 and the output signal 10 of the signal transmission Device failure, as well as the master oscillator 11, the control unit 1 and the auxiliary input 13 of the control module of the counting module of the output counter 9.

The signal inputs of multiplexer 5 are respectively connected to the inputs of recording units 2, and the signal inputs of multiplexer 6 are respectively connected to the outputs of sensors 4 of the recording current. The sensor inputs 4 write current connected to the corresponding

magnetic heads 3. The output of the multiplexer 5 is connected to the first input, and the output of the multiplexer b is connected to the second input of the control unit 7. The output of the control unit 7 is connected to the information input of the self-blocking counter 8 ,. the output of which is connected to the information input of the output counter 9, the output of the counter 9 is connected to the output bus 10. The output of the master oscillator 11 is connected to the installation input

Self-blocking counter VIS by the input of the control unit 12, the output group of which is respectively connected to the control inputs of multiplexers 5g and 6. The additional output of the control unit 12 is connected to the installation input of the output counter 9, which has the additional input 13 of the installation of the counting module. .I

The control unit 7 (Fig. 21 contains a selector of 14 fronts (front and rear) pulses, a pulse expander 15, an interdiction element 16, an AND 17 element and an OR 18 element, with this one input of the control unit (input connected to the output of multiplexer 5) connected to the input of the pulse front selector 14. One output of the front 14 selector (output of a short pulse formed on the leading edge of the input pulse of the selector) is connected via AND 17 and OR 18 elements to the output of the control unit, the other output of the front selector 14 (short pulse output on the falling edge of the input pulse of the selector) is connected to the first signal input of the prohibition element 16, the output connected to another input of the element OR 18, and the other input of the control unit (input connected to the output of the multiplexer 6) is connected to another input of the element And 17 and through the expander 15 pulses - with the second blocking input element 16 for. Ban.,;

The self-blocking counter 8 (FIG. 3) contains a pulse counter 19, a delay element 20. and a trigger 21, while the information input of the self-blocking counter is connected to the information input of a pulse counter 19, the overflow output of which is the output of the counter 8 and is connected via delay element 20 to one input of the trigger 21, the other input of which is the installation input of the self-blocking counter 8 and is connected to the installation input of the pulse counter 19, the counting resolution input of which is connected to the output of the trigger 21.

Control unit 12 is made on the basis of a binary pulse counter whose counting input is connected to the output of the master oscillator 11, the bit outputs (parallel binary code outputs) are respectively connected to the control inputs of multiplexers 5 and 6, and the overflow output of this binary pulse counter (additional output block 12) control is connected to the installation input of the output counter 9.

The device works in the following way. Recorded information in the form of pulse code sequences is transmitted by bus 1 to the inputs to the recordings — to the inputs of their recording units 2, in recording units 2 the necessary conversions of the input information are performed in accordance with the recording method used and the recording current is generated in the respective magnetic heads 3. Sensors 4 of the recording current pick up short (in duration) pulses that occur at the terminals of the windings of the magnetic heads every time they turn off or change (switch) the direction of the current in them. si. At the same time, at the outputs of sensors 4 of the recording current, short rectangular pulses are formed the number and relative localization of which is in strict accordance with the input code sequences of the record. Syvayeluy information in the normal operation of units 2 records and the health of the magnetic, heads 3 and their chains. In the process of recording information, the device constantly monitors the operation of the recording channels, i.e. blocks 2 recording and magnetic. heads 3. For monitoring all channels in the device, only one control unit 7 is used, which alternately periodically controls each recording channel. The time interval during which a periodically separate recording channel is continuously monitored is a monitoring cycle. The control unit 7 by the incoming reaction pulses of the magnetic heads 3 determines the presence of a recording current of the required magnitude and switching its direction. When an open circuit in the winding circuit of the magnetic head 3 pulses at the output of the corresponding sensor 4 write current are missing. In this case, the output pulses of the Selector are 14 fronts (Fig. 2), corresponding to the back edges of the information pulses, PASS through the prohibition element 16 (at the second input of which there are no blocking response pulses of the magnetic head in this case) and output OR 18 block 7 control l. In the case of a short circuit in the water of the magnetic head 3, a potential signal is set at the output of the corresponding write current sensor, which opens element AND 17 of the control unit 7 for passing through it the output pulses of the front selector 14 corresponding to the leading edges of the information pulses. Next, the output pulses of the element AND 17 pass through the element OR 18 to the output of the control unit. The output pulses of the control unit 7, each of which indicates the presence of one fault in. The recording channel is counted by a self-blocking counter 8. To ensure that only each ONE cycle corresponding to a given cycle is counted in each error control cycle, the recording channel at the beginning of each self-blocking control cycle with the counter B is set to the zero state of the master oscillator 11, whose frequency determines the duration of the control cycle. The permissible number of errors in one monitoring cycle in the transmission of information by each recording channel is set by the capacity of counter 8. When fully filled, it issues a signal. The presence of a signal (for example, a pulse) at the output of the counting circuit 8 in one of the control cycles indicates that, in accordance with this recording channel, the accuracy of information transmission decreased below the required one; To ensure that during one control cycle, the self-locking counter K 8 gave only one im-. pulse and with a high frequency of a trace of failures of one channel, it is made with self-blocking after issuing the first pulse. In the event of overflow, the counter 19 (Fig. 3) gives out a pulse that passes to the output, and also arrives with a delay to the second input of the trigger 21. The trigger 21 is reset to the initial state. In this case, its output potent signal is removed from the counting resolution input of the pulse counter 19. At the beginning of each monitoring cycle, the pulse counter 19 is set to the zero state and the flip-flop 21 is switched. At THIS, the output signal of the flip-flop 21 gives permission to the pulse counter 19 to be counted. The specified number of errors, relative to which their actual number is monitored, can be varied by changing the capacity of the counter 19, to allow the flexibility to change the confidence level threshold based on the specific structure of the recorded digital signals. The output signals of the self-blocking counter are counted by the output counter 9. It is periodically zeroed by pulses generated by the control unit 12 each time after the end of the last control cycle. Thus, the counter 9 records the number of failed recording channels. The failure criterion of a multichannel magnetic recorder required for automatic monitoring, which is selected based on the number of failed channels (for a given type of recorded digital data stream), is easily established by a corresponding change in the counting module of the counter 9 via the additional input 13. When overflowed, the counter 9 outputs to the output bus 10 devices signal command Failure of the device, indicating that the number of failed recording channels of the device has exceeded the allowable one.

As a base object, a known device is included, which is part of the multichannel equipment and provides signaling of the failure of each recording channel separately and determining the moment of failure of a magnetic device as a whole (for subsequent switching on of a similar, backup device) with the operator.

The technical advantage of the proposed device, as compared with the base one, is that it provides the possibility of automatic control of the failure time of the multichannel magnetic recording apparatus by any given failure criterion. As a result, a significant increase in the accuracy of automatic detection is achieved.

0 moment of switching records of information to the backup device in case of failure of the main, t, e. provides a significant reduction in the error of the reserved and. In connection with

5, this reduces both the flow rate of the magnetic media (precluded switching on the backup device) and loss of the recorded information (ensuring that the backup

0 apparatus and more use. information capacity of the main unit).

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Claims (1)

DEVICE FOR MONITORING MULTI-CHANNEL MAGNETIC RECORDING APPARATUS, containing recording current sensors connected to magnetic ₍ boats of recording channels, a control unit whose inputs are connected through the first and second multiplexers to the inputs of the recording channels and to the outputs of the recording current sensors, respectively, the control unit, the input is connected to the output of the master oscillator, and the outputs connected to the corresponding control inputs of the multiplexers, and an output counter, characterized in that, in order to provide the ability to control the open call a predetermined number of channels, it introduced self-locking counter connected between the output of the control and data input the output of the counter with an additional input account module installation, the installation input of which is connected to an additional output of the control unit and the installation consist: ^ samoblokirukschegosy counter connected to the output of the master oscillator. u with Q0 SaZ