SU1550606A2 - Leading clock signal shaper - Google Patents

Abstract

The invention relates to a pulse technique and can be used to synchronize visualization devices using a spatial selection method for observing objects and objects in a closed atmosphere, for example, in a fog. The aim of the invention is to increase the reliability of operation by eliminating the appearance of spurious pulses during the absence of an input pulse sequence or part of its pulses, which is achieved by introducing new electrical connections between functional elements. The shaper contains the trigger 1, the first, second, third and fourth elements AND 3, 5, 14 and 15, the first and second counters 4 and 6, the first, second, third elements OR 7, 9 and 12, the first and second one-shot 8 and 11 , generator 13 pulses, input bus 2, output bus 10. 1 Il.

Description

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The invention relates to a pulse technique and can be used to synchronize visualization devices using a spatial selection method for observing objects and objects in a turbid atmosphere, for example, in a fog.

The purpose of the invention is to increase the reliability of operation by eliminating the appearance of parasitic pulses during the absence of an input pulse sequence or part of its pulses.

FIG. 1 shows the electrical functional diagram of the proposed device; in fig. 2 - time diagrams that show his work.

The driver of the advance signal contains trigger 1, the counting input of which is connected to the input bus 2, the direct output is connected to the first input of the first element 3 and the input of the first counter of 4 pulses, the inverse output of the trigger 1 and 5 the input of the addition of the second counter 6 pulses, the subtractive input of which is connected to the output of the first element AND 3, the outputs through the serially connected first element OR 7 and the first one-shot 8 are connected to the first input of the second element OR 9 output second Element I 5 is connected to the subtraction output of the first counter 4 pulses, the output of the second element OR 9 is connected to the output bus 10, and the second input is connected through the second single-oscillator 11 and the third element OR 12 in series with the outputs of the first counter 4 pulses, the counting inputs The first 4 and second 6 pulse counters are connected to the generator output 13 pulses, the third and fourth elements are And 14 and 15, the outputs of which are connected to the installation inputs of the first and second counters, 4 and 6 pulses, the first inputs - to the input bus 2, second These inputs are to the inverse and direct inputs of the trigger 1, respectively, and the second inputs of the first and second elements AND 3 and 5 are connected respectively to the outputs of the first element OR 7 and the output of the third element OR 12, and the input of the first counter 4 is connected to the auxiliary input of the first one-shot 8, and the input of the addition of the second counter 6 pulses with

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united with the additional input of the second one-shot 11.

The shaper works as follows (Fig. 1).

The pulses of the input pulse sequence (VIL) of a constant frequency come from the input bus 2 to the counting input of the trigger 1, alternately changing its state and the potentials of its forward (Fig. 2b) and inverse (Fig. 2c) outputs. The potentials control the operating mode of the two reversible counters 4 and 6, the counters of which are counted, the pulses of the generator 13, This control in the driver is arranged so that the operating modes of the counters are shifted by one VIP period (, and), t. e. when one counter is in Addition mode, the other counter is currently in the Subtraction or Stop modes.

To form a single clock pulse leading the corresponding VIP pulse, the shaper uses a cyclic sequence of two modes of operation of counters 4 and 6 — Addition and then Subtraction. In the latter mode of operation, a sync pulse is formed, which is ahead of every second impulse of the VIP by time tv. This sync pulse appears at the output of that one-shot 8 or 11, which through element 7 or 12 is connected to a meter operating in the Subtraction mode. Due to the shift in operation, the modes of the counters 4 and 6 at the output of the single-oscillators 8 and 11 (fig.2z.n) are alternately formed with a frequency that is two times less than the frequency of the VIP, the sync pulse, which are combined in element 9 and arrive at the output bus 10 in the form of a sequence of pulses (FIG. 2o), which coincides in shape with the VIP and is ahead of each of its pulses by time t0,

The formation of a sync pulse is preceded by the supply of a high resolution potential to the gate input of the one-shot 8 (Fig. 2g) from the direct output of the trigger 1 (Fig. 26) and respectively to the same input of the one-shot 11 (Fig. 2m) from the inverse output of the trigger 1 (Fig. 2c) . Taking into account the cyclical operation of counters 4 and 6, a detailed description of the operation of the imaging unit is performed on a time interval that includes two periods

HIL, for example, between the second and fourth pulses for the control circuit of the operating mode of the counter 6 and between the first and third pulses of the HIL for the corresponding circuit of the counter 4 (FIG. 2a).

The control circuit of the operation of the counter 6 contains the elements of the elements And 15 and 3 and - works as follows.

Assume that at the moment of the arrival of the second VIL pulse, the counter 6 was in the Stop state (Fig. 2d), which corresponds to the value of the low potential O at the inputs C and B of the counter 6. Since the input C of this counter is directly connected to the inverse output of the trigger 1, the direct output of this trigger was at a high potential 1 (FIG. 26), which is fed to the first input of the element 15, the first input of the element 3 and the auxiliary input of the one-shot 8. The high potential of the second pulse

2d), so the high potential of the direct output of trigger 1 (Fig. 26) permits passage of 1 from the output of the element OR 7 to the input B through the element AND 3. In this mode of operation of the counter 6, a sync pulse is formed that is ahead of time t0 next fourth impulse VIL (Fig.2A),

since the high potential of the direct output of the trigger 1 removes the blocking of the one-shot 8 via its additional input. The sync pulse shaping process is determined by the mechanism

the interaction of the counter 6, the element OR of the single-oscillator 8. At the moment of the fourth impulse of the VIL appears, at the input of the former, all bits of the counter 6 are zeroed, so

0 as the high potential of the VIL impulse passes through the second input of the element I 15 to the input U of the counter 6 (fig.2d), since at the direct output of the trigger 1 and, therefore, at the first input of this

VIL during the occurrence of the second input element 25, there is a high potential of the element 15 and, respectively, at the input At counter 6 (FIG. 2 d), the bits of this counter are zeroed. The condition of the state of the stop of the counter 6 at the input B at the same time is realized by the low potential of the output of the element OR 7 (Fig. 2e), which, the passage to the input of the element FROM, is at the entrance B of the counter 6.

The cycle of operation of the control circuit of the counter 6 begins at the moment of termination of the second impulse VIL pulse (Fig. 2a), in which the state of the trigger 1 is set to the opposite, since a push-pull trigger with a counting input, for example T-, is used as the trigger element. type At this point in time, the forward and inverse outputs of trigger 1 appear, respectively, low (Fig. 26) and high (Fig. 2c) potentials, the first of which prevent the third impulse from passing to the input Y of counter 6 and blocks the formation of an impulse. the output of the one-shot 8 for one period of VIL (fig.2zh), and the second potential converts the counter 6 to the mode Addition (fig.2g). This mode continues until the next third pulse (Fig. 2a) returns trigger 1 to its initial state (Fig. 26, 2c). In this case, the counter 6 stops and at the next moment switches to the Subtraction mode (Fig.

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al (Fig. 26). At the moment when the fourth VIL ends, the new cycle of operation of counter 6 begins, in which the sequence of cycle operations and the corresponding states of the elements included in the control circuit of counter 6 are repeated again.

The formation of a sync pulse, which is performed in the operation mode Subtraction of counter 6, is determined by

The collaboration of this counter 6, the element OR 7 and the one-shot 8. The work is considered under conditions taken for definiteness, i.e. Counter 6 is binary, and the one-shot 8 produces a pulse only in the case of a potential drop at its input from a high level to a low level and in the presence of a high r resolution potential at its input. At the output of the lower of the higher bits of the counter 6, connected to the inputs of the element OR 7, after the termination of the second VIL impulse, after a time interval, a high potential appears. As a result, a high potential also occurs at the output of the element OR 7 (Fig. 2e). Subsequently, Addition mode leads to an increase in the value of the logical number at the outputs of counter 6. Despite this, the high potential at the output of the element OR 7 at the time t & (Fig. 2e) does not give

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det to the occurrence of a pulse at the output of the one-shot 8 (Fig, 2h). In addition, the operation of the one-shot is blocked by a low potential coming from the direct output of flip-flop 1 (Fig. 2g). In the following mode, Subtraction, which begins after the appearance of the third VIL impulse, there is a gradual decrease in the value of the logical number in the bits of the counter- chip 6. As a result, after a certain period of time, all the higher bits of the counter zero out, , the element OR 7 from high to low, the operation of the one-shot 8, since at its additional input there is 1 from the direct output of the trigger 1, and the appearance at the output 2Q of the one-shot of the sync pulse, which is ahead of time tQ, the arrival on the input bus 2 of the fourth pulse generator VIL (Fig. 2h). At the time of the formation of the clock pulse, the counter 6 25 stops (Fig. 2d), since the low potential at the output of the element OR 7 (Fig. 2e) through the second input of the element And 3 arrives at the input B of the counter 6. At the end of the cycle of operation of the control circuit of the counter 6 its lower bits, which are not connected to the element OR 7, form the remainder of a logical number, the value of which is related to time t by the following formula tn 2 ™. T

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where tp is the number of low bits of counter 6;

Tststs - the period of the following counting pulses .40

In this case, the total number of digits n of the counter, equal to the sum of the lower and upper digits, is determined depending on the maximum possible value of the period of VIN according to the expression

n log2 (TM (W / T.c4),

The operation of the control circuit of the counter 4 and the formation of a sync pulse at the output of the one-shot 11 is similar to the control circuit of the counter 6 and the one-shot 8, since the process of functioning of these circuits (Fig.2i-n) is almost the same and only shifted in time (forward) by one VIL period.

15506068

Thus, when a sync signal generator, representing a constant frequency VIP, arrives at the input bus 2, its output bus 10 produces a sync pulse sequence ahead of time t0 or an advance sync signal.

In the case of the termination of the arrival of the VIP impulses on the bus 2, the driver operates as follows.

Counter 6 after the arrival of the 6th and last impulse of the VIP goes to the Addition mode (Fig. 2d), at which a periodic (with period T) occurs, all its bits are zeroed and the potential at the output of the element OR 7 changes from a high to a low level (Fig. 2e). In this mode of operation of the counter at the additional input of the one-shot 8, the potential of the direct output of the trigger 1 is kept continuously low. Due to this, the one-shot 8 does not work and does not form parasitic sync pulses.

Claims (1)

After the arrival of the sixth VIP pulse, the counter 4 goes into the Subtraction 1 mode, in which after some time the single vibrator 1 generates one parasitic sync pulse (Fig. 2i), because the additional potential of the inverse output of the trigger 1 (Fig. 2m) is present at the auxiliary input of this single vibrator . At the moment of the formation of the synchro pulse, the counter 4 stops, since the low output potential of the element OR 12 through the element 5 goes to the input B of this counter. Subsequently, counter 4 is in Stop mode. Invention Formula thirty 45 50 Shaper advanced sync on auth.St. No. 1385276, characterized in that, in order to increase the reliability of operation, the input of the addition of the first pulse counter is connected to the auxiliary input of the first one-oscillator, and the input of the addition of the second pulse counter is connected to the additional input of the second one-oscillator. Shaper advanced sync on auth.St. No. 1385276, characterized in that, in order to increase the reliability of operation, the input of the addition of the first pulse counter is connected to the auxiliary input of the first one-oscillator, and the input of the addition of the second pulse counter is connected to the additional input of the second one-oscillator. 1 2 3 4 5 6 hp i i i i i i i i 0 п п ч -. C | "CIf 4Jtf j | - Well P P and 14-1- I t-i BUT P FIG. g