SU1277206A1 - Device for checking magnetic tape recorder - Google Patents

Abstract

The invention relates to instrumentation engineering and makes it possible to increase the reliability of the control by periodically using the self-monitoring mode. A feature of the generated test signal is that each character of the generated sequential code is equal to the inverse of the sum modulo two two previous characters. After recording the test test, the recorded test test is played by the playback unit 1, which extracts the recorded information and clock pulses, which through the switches 16 and 15 arrive at the input of the register 8, respectively. The presence of errors in the individual reproduced characters results in output pulses an EXCLUSIVE OR 11 cell that is gated using the BAN 12 cell and sent to the counter 13 pulses, which, before being monitored, are zeroed by a signal from the switch 17, In the self-monitoring mode, the recording unit 3 of the magnetic recording apparatus 2 and the reproduction processing unit 1 are excluded from the test recurrent sequence circuit and the readings of the counter 13 allow to judge the device operability. 2 Il. tsD 1chR O5

Description

The invention relates to instrumentation, namely, devices for controlling a magnetic recording apparatus.

The purpose of the invention is to increase the reliability of the control by periodically using the self-monitoring mode.

Figure 1 shows the functional diagram of the device; figure 2 is a functional diagram of the pulse error generator.

The device dp control of the magnetic recording device contains a playback unit 1 connected by an input through the magnetic recording device 2 to the output of the recording unit 3, a pulse generator A connected by an output to the first input of the first register 5 connected by the outputs through the first element OR 6 to the input of the element NOT 7. connected by the output to the second input of the first register 5, the second register 8 connected by the outputs through the serially connected second element EXCLUSIVE OR 9 and the second element NOT 10 to the first input of the third ele cient exclusive OR 11, the output connected to the first input element inverted 12 output connected to an input 13 of a pulse counter.

In addition, the device for controlling the magnetic recording apparatus contains the first, second, third and quarter switches .14-I7 and the driver 18 of the error pulses, the first switch 14 being connected to the input and output of the first element HE 7 by the first and second inputs and the output to the third input the driver 18 pulses of error, connected by the first input to the interconnected generator output of 4 pulses. and the first input of the error pulse generator 18 and the second input to the first output of the playback unit 1 connected by the second output to the first input of the third switch 16 connected by the second input to the interconnected output of the first switch 14 and the input of the 3 record, the third input to the interconnected the third input of the second switch 15, the second input of the driver 18 error pulses and the first output of the fourth switch 17 and the output to the second input of the third connected to each other

the element of the STAFFLER 11) 1and 1 and the first input of the second register 8 connected by the second input to the second output of the second switch 15 interconnected to each other and the second input of the BAN 12 element, and the counter

13 pulses connected installation input with the second output of the fourth switch 17.

The driver 18 error pulses contains a counter 19 pulses, the element And 20 and the trigger 21, connected by inputs to the inputs of the imager 18 error pulses and counter

5 19 pulses directly and one of the inputs through successively connected element I 20 and counter 19 pulses.

The device works as follows.

0 way.

In the control mode of the magnetic recording apparatus 2, a control signal is generated at the output of the fourth switch 17, which sets the output pulse voltage generator O at the control input of the first switch 14, thereby providing the output to

Q switch 14 signal from its input. The control signal from the output of the fourth switch 17 is also fed to the inputs of the commentators 15 and 16, allowing the outputs of the switches 15 and 16 to pass from the outputs of the playback unit 1. General torus 4 pulse generates clock pulses with a repetition frequency equal to the frequency of recording information on a magnetic medium, which arrive at the first input of the sequential first register 5, which, together with the accumulation element of the ARCHE or 6, form a recurrent sequence sensor, which

 generates a pseudo-random signal coming through the first switch

14 to the input block 5 records. A feature of the test signal generated in this way is that

0 each character of the generated sequential code is equal to the inverse modulo 2 of the two previous characters The recording unit 3 generates a signal which is recorded on the monitored magnetic recording apparatus 2. After the recording of the test test (or simultaneously with the recording), the recording is played,

control test performed by playback unit 1, which extracts the recorded information and clock pulses, which through the switches 16 and 15 arrive at the inputs of the sequential second register 8 respectively. Element EXCLUSIVE OR 9 performs: summing up the second bits of the second register 2 modulo 2 , the result of summing from its output through the second element NOT 10 is fed to the first input of the third element of the INSAID or OR 1 1, and which in this case performs the functions of a coincidence circuit. So, when an EXCLUSIVE OR 11 element arrives at both inputs, which corresponds to reproducing information without errors, the voltage at its output is O. The presence of errors in individual reproduced symbols leads to the appearance of pulses (three for each error) at the element output EXCLUSIVE OR 1f, which are gated using the prohibition element 12 and arrive at the counter 13 pulses (counter 13 incorporates a pre-divider of the number of pulses by 3) which, before the start of control, is zeroed by a signal, the post Payuschie of the fourth switch 17,

In the self-monitoring mode, at the output of the fourth switch I7, a control signal is generated, which is fed to the input of the error pulse generator 18, as a result of which the error pulse generator 18 generates positive polarity pulses, but the phase and power coinciding with one information cycle and low repetition rate, for example, I Hz, which arrive at the control input of the switch 14 and provide, once per second, the output of the switch 14 of one clock cycle of information from the input of the switch 14, to which the incoming The test sequence is inverse. In this way, a test recurrent sequence is formed at the output of switch 14, into which errors that occur at a frequency of 1 Hz are artificially introduced. Also, the control signal of the fourth KOMf-fyTaTopa 17 output goes to the control inputs of switches 15 and 16, ensuring passage to the outputs of switches 15 and (6 signals from the output of the pulse generator and from the output of the switch 14, respectively. Thus, in the self-monitoring mode, the recording unit 3, the magnetic recording unit 2 and the playback unit 1 are excluded from the test circuit howl recursive sequence and hence counter indications 13 allow to judge the bone rabotosposob10 proposed device.

Claims (1)

Claims. Device control device 15 magnetic recording, containing a playback unit connected by an input through a magnetic recording apparatus to the output of a recording unit, a pulse generator connected by an output to the first input of the first register connected by outputs through the first element of the OPEN ALREADY connected to the output the second input of the first register, the second register connected by the outputs through the serially connected second element EXCLUSIVE OR or the second element NOT to the first input of the third element EXCLUSIVE OR, subconnect The output to the first input of the BANCH element connected to the output of the pulse counter, characterized in that, in order to increase the reliability of the control by periodic use of the self-monitoring mode, the first, second, third and fourth switches and the driver of error pulses are entered into it, the first the switch is connected by the first and second inputs to the input and output of the first element; NOT; the third input is connected to the output of the error pulse generator, under; connected by the first input to the first output of the second switch connected by the first input to the connected between the output of the pulse generator with the second input of the error pulse generator and the second input to the first output of the playback unit connected to the second output to the first input of the third switch connected by the second input to the interconnected output of the first switch and the input of the recording unit, the third input to the interconnected third input of the second switch, the second input of the error pulse generator and the first output of the fourth switch and the output to the second input of the third element EXCLUSIVE1R1EE OR or the second input of the second register connected to each other to the second output connected to each other switch on the second input of the element BANNER, and the counter pulses connected by the installation input, the second output of the fourth switch, nineteen .C5frt7c ) C (7ff - 21