SU291193A1 - LIBRARY i - Google Patents

Description

This invention relates to the field of computing technology and is intended for use in storage devices by a pair of moving carriers. The main author. St. No. 225549, issued to a synchronization device and intended to generate clock signals when reading information from a magnetic mite, contains a time discriminator that converts the time interval between two series of pulses into voltage, an adjustable delay line, a trigger, a pulse shaper combined by a feedback line. . The said device has a low accuracy in output phase with input pulses, therefore, it can monitor the input signal frequency only in the presence of a voltage error at the output of the time discriminator. Suppose that at the output of the device a pulse appears with a period TI different from the minimum period Go. Then, if there is a signal at the input with a period of Ti, the error voltage of the temporary discriminator will not be generated, as a result of which the next pulse will be output with the nominal period of Go. Thus, in this device there is a periodic deviation of the output frequency from the input frequency. The purpose of the present invention is to improve the accuracy of the synchronization device. This goal is achieved by introducing into the device a summing unit that algebraically sums the voltage produced by the temporary discriminator. Due to this, the periods of successive output pulses do not change abruptly from the nominal value to the value corresponding to the input pulses. FIG. 1 is a block diagram of the device according to the invention; FIG. 2 - timing charts of the known and proposed devices. The device contains a temporal discriminator 1, the inputs of which are connected to the ground 2 sync pulses and a pulse shaper 3 connected to a single output of trigger 4. The counting input of trigger 4 is connected to the outputs of the valve 5 and the driver 6 of pulses. The valve 5 is controlled by the potential from a single output of the trigger 7, which in the state "1" is set as the first clock pulse. The pulse input of the valve 5 is connected to the output of an adjustable delay line 8, the pulse input of which is connected to the outputs of the valve 5 and the pulse shaper 6. Thus, the adjustable delay line 8 and the valve 5 represent an adjustable generator triggered by a pulse from the output

shaper 6. The delay time (thereby the pulse repetition frequency at the generator output) is controlled by the voltage from the output of the smoother 9, the input of which is connected to the output of the time discriminator via the summing unit 10. The zero inputs of the flip-flops 4 and 7 are connected to the bus //, in which an immobilizer appears to reset the device. The output of the driver 12 pulses connected to the zero output of the trigger 4, is connected to the bus clock signals 13.

The device works as follows. The first input pulse puts trigger 7 in the state "1. The pulse generated by shaper 6 puts trigger 4 into state "1 and enters the input of adjustable delay line 8. Thus, the first pulse triggers the generator, the generation frequency of which is twice the frequency of the input pulses, and arrives at the time discriminator input. The error voltage is summed up and remembered by the summing unit 10, which, through smoother 9, controls the delay time of delay line 8. The pulses taken from the driver 12 correspond to the clock signals delayed by half of the current average period. In the case of input signals falling out, the time discriminators usually produce zero voltage.

Therefore, in such cases, the voltage at the output of the summing unit 10 does not change, and the clock pulses are output at a frequency equal to the current average frequency of the input pulses before the latter fall.

After a gap of outgoing input pulses, when they appear again, the frequency of the output signals is adjusted to the new value of the current average frequency. When a pulse of the end of the access to the magnetic tape on the splint arrives, the flip-flops 4 and 7 turn over into the zero state. The valve 5 closes and the generation of the clock signals is stopped.

FIG. 2 shows the diagrams showing a higher accuracy of the proposed device compared with the known. Plots 14, 15, 16 show, respectively, the input and output pulse sequences and the voltage at the output of the temporary discriminator (the frequency of the input pulses is less than the nominal one). Plots 14, 15, 16 show the same voltages for the proposed device, and plot 17 shows the form of the voltage at the output of the adder.

Subject invention

A device for generating synchronizing pulses when reading information from a magnetic tape on ed. St. No. 225549, characterized in that, in order to increase the synphase of the output clock with the input signals, it contains a summing unit, the input of which is connected to the output of the time discriminator, and the output to the input of the smoother.

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