RU2054796C1 - Pulse signal sequence monitoring device - Google Patents

Abstract

FIELD: automatic control and computer engineering. SUBSTANCE: device has multichannel commutator, pulse counter, decoder, comparison unit, and input buses of device. EFFECT: improved design. 2 dwg

Description

 The invention relates to a pulse technique and can be used in automation and computer technology to control pulse sequences.

A device for controlling the sequence of alternating pulse signals containing an AND element, a pulse counter, a multi-channel switch, the first group of inputs of which is connected to the input buses, and the second control group of inputs is connected to the outputs of the pulse counter, an inverter and an OR element, the output of the multi-channel switch is connected to the input counter and through an inverter to the first input of the AND element, the second input of which is connected to the output of the OR element, the inputs of which are connected to the input buses, the output of the AND element is connected n to the output bus of [1]
A disadvantage of the known device is that it in the process of monitoring the sequence of pulse signals does not detect errors associated with the simultaneous receipt of signals on two or more input buses.

 It is also known a device for monitoring the sequence of alternating pulse signals containing a multi-channel switch, the first and second elements OR, the element NOT, the group of elements AND, the counter, the element And, the decoder, input buses, the first and second output buses.

 The input buses of the device are connected to the information inputs of the multi-channel switch, the inputs of the first OR element and the first inputs of the elements of group I. The control group of inputs of the multi-channel switch is connected to the outputs of the counter and the inputs of the decoder, the outputs of which are connected to the second inputs of the elements of group I.

 The outputs of the elements of the AND group are connected to the inputs of the second OR element, the output of which is connected to the second output bus of the device. The output of the multi-channel switch is connected to the input of the counter and the input of the element NOT, the output of which is connected to the first input of the element I.

The output of the first OR element is connected to the second input of the AND element, the output of which is connected to the first output bus of the device [2]
The disadvantage of this device is that it does not allow reliable control of the sequence of pulse signals generated by the principle of the distribution of pulses on a circular shifting register. So, in the absence of signals at the outputs of the pulse distributor (if a unit disappears in the annular shift register of the pulse distributor), the control device does not generate an "Error" signal.

 The aim of the invention is to improve the quality control sequence of alternating pulse signals.

 The goal is achieved by the fact that in the device for controlling the sequence of alternating pulse signals containing a multi-channel switch, pulse counter, decoder, a comparison unit is introduced.

 The essence of the invention lies in the fact that in the proposed device, the control of the sequence of alternating pulse signals is carried out by comparing two position codes received at the first and second groups of inputs of the block.

 The first position code corresponds to the combination of ones and zeros currently on the input buses of the monitoring device in accordance with the sequence of pulse signals.

 The second position code is formed by the joint work of the multichannel switch, pulse counter, and decoder included in the control device. With the correct alternation of signals on the input buses, the two position codes will always be equal to each other and there is no "Error" signal on the output bus. In the case of a violation of the order of signals to the input buses, when several signals are received instead of one, if there is a constant signal on the input buses, as well as if there are false signals on the input buses during the next monitored signal or the absence of signals on the input buses from the above cases, non-comparison of two position codes and the signal "Error" is generated on the output bus.

 The drawing shows the proposed device.

 A device for monitoring the sequence of pulse signals contains a switch 1, a pulse counter 2, a decoder 3 and a comparison unit 4. The information inputs of the switch 1 are connected to the input buses 5-1-5-N and the first group of inputs of the comparison unit 4. The output of the multi-channel switch 1 is connected to the input of the pulse counter 2, the outputs of which are connected to the second control group of the inputs of the multi-channel switch 1 and the inputs of the decoder 3, the outputs of which are connected to the second group of inputs of the comparison unit 4, whose inverse output is connected to the output bus 6.

 The block diagram of the proposed device (see figure 1) is presented for the case of a four-input sequence of alternating pulse signals generated by the pulse distributor on a four-digit ring shift register.

 The control device includes a four-channel switch, a two-bit pulse counter, a four-output decoder and a four-bit comparison unit. With an increase in the number of inputs of a pulse signal sequence, the pulse counter width increases accordingly, the number of decoder outputs increases, the number of control inputs of a multichannel switch increases, the width of the first and second groups of inputs of the comparison unit does not decrease the quality of control.

 The device operates as follows.

 Before starting work, the counter 2 pulses is set to zero by any known method (reset circuit is not shown). The outputs of the counter 2 pulses connected to the second control group of inputs of the multi-channel switch 1, specify the number of the polled input bus.

 When setting the counter 2 pulses to zero, the output of the multi-channel switch 1 is connected to the first input bus 5-1. The signal received at the first input of the multi-channel switch 1 passes to its output and the input of the counter 2 pulses. At the end of the input signal, the pulse counter 2 changes its state to the next one and thereby the next one is connected to the output of the multi-channel switch 1, i.e. second input bus 5-2. With the correct sequence of alternating pulse signals, this process of connecting the input buses 5-1-5-4 to the output of the multi-channel switch 1 is repeated.

 Each of the signals arriving at the input buses 5-1-5-4 also goes to the first group of inputs of the comparison unit 4. Moreover, the codes 1000, 0100, 0010, 0001, 1000, 0100, etc., are alternately generated at the inputs of this group of inputs of the comparison unit 4

 The second group of inputs of the comparison unit 4 receives signals from the outputs of the decoder 3 in accordance with the binary code supplied to its inputs from the output of the counter 2 pulses.

 With the sequential arrival of pulse signals to the input buses 5-1-5-4 of the device, the position codes 1000, 0100, 0010, 0001, 1000, 0100, etc., will be sequentially generated at the outputs of the decoder 3.

 With the correct alternation of signals on the input buses 5-1-5-4 of the device, the code is compared on the first group of inputs of the comparison unit 4 with the position code from the outputs of the decoder 3, while on the inverse output of the comparison unit 4, and therefore on the output bus 6 there is no error signal.

 If there is a constant signal on the controlled input bus, which can happen, for example, in the event of a failure of a trigger (constant unit) of the ring shift register of the pulse distributor, the 2 pulse counter does not change its state, since it works by decreasing the input signal, and therefore does not connect the next input bus to the output of multichannel switch 1. When a signal arrives on the next input bus, the codes are compared at the inputs of the comparison unit 4. So, if there is a constant signal on the second input bus 5-2 with the signal arriving on the third input bus 5-3, the codes on the first and second groups of inputs of the comparison unit 4 will be equal to 0110 and 0100, respectively. In this case, the comparison unit 4 outputs to the output bus 6 signal "Error".

 With the simultaneous absence of signals on the input buses 5-1-5-4, which can happen, for example, when a unit disappears in the ring shift register of the pulse distributor, the code 0000 is present on the first group of inputs of the comparison unit 4. At this time, the second group of inputs of the block 4 of the comparison, there is any other code other than the code 0000. So, for example, if a unit disappears in the third category of the ring shift register of the pulse distributor, the code of the second group of inputs of the comparison unit 4 will be 0010. At the same time, there are 6 forms on the output bus ruetsya signal "Error".

 If the alternation of signals on input buses 5-1-5-4 is violated, for example, after a signal arrives on bus 5-1, a signal is sent to bus 5-3, this signal does not pass to the output of multi-channel switch 1, since the code is on the second control group inputs of the switch 1 connects to its output input bus 5-2. In the absence of signals at the output of the switch 1, the state of the pulse counter 2 does not change, i.e. remains as it was after the signal was received on the first input bus 5-1. With the arrival of the signal on the bus 5-3 on the first and second groups of inputs of the comparison unit 4, the codes will be 0010 and 0100, respectively. In this case, the comparison unit 4 gives an error signal to the output bus 6.

 Monitoring the simultaneous occurrence of false signals on the input buses 5-1-5-4 during the next one is carried out by comparing the codes at the inputs of the comparison unit 4. Moreover, the position codes 1000, 0100, 0010, 0001, 1000, 0100, etc., formed by the decoder 3, are sequentially fed to the second group of inputs of the comparison unit 4 as in the case of the correct alternation of signals on the input buses 5-1-5-4 of the control device. The first group of inputs of the comparison block will contain a positional code consisting of two or more units. So, when a false signal appears on the first input bus 5-1 during the operation of the next signal on the third input bus 5-3, the position code at the inputs of the comparison unit 4 will be 1010 instead of the correct code 0010.

 In this case, the comparison unit 4 provides an error signal to the output bus 6.

 When two pulses arrive at any of the input buses 5-1-5-4, instead of one, the control device generates an alternation order violation signal on the output bus 6 as follows. At the end of the input signal, the pulse counter 2 is set to the next state and connects the next input bus to the output of the switch 1. Decoder 3 generates a position code for the next input bus. The signal received a second time on the same input bus does not go to the output of the multi-channel switch 1 and does not change the state of the counter 2 pulses.

 Thus, on the block 4 of the comparison receives two positional codes that differ from each other. On the first group of inputs of the comparison unit 4 there is a position code of this input bus, and the second group of inputs of the comparison unit 4 receives the position code of the next input bus from the outputs of the decoder 3.

 So, when two pulses appear on the second input bus 5-2 instead of one, the position codes on the first and second groups of inputs of the comparison unit 4 will be equal to 0100 and 0010, respectively. An error signal is generated on the output bus 6.

 The operation diagram of the device for a four-input sequence of alternating pulse signals is presented in figure 2. The sequence of alternating pulse signals, the signals from the outputs of the pulse counter, the decoder and the signal "Error" are shown.

 The diagram vertically shows the input buses 5-1, 5-2, 5-3, 5-4, the outputs of the pulse counter СЧ1Р, СЧ2Р, the outputs of the decoder Дш0, Дш1, Дш2, Дш3, the output bus "Error", and the horizontal area , characterizing the operation of the control device: area a with the correct alternation of the input pulse signals; area b if there is a constant signal on the input bus 5-2; region in with the simultaneous absence of signals on the input buses; region g in violation of the order of arrival of the input signals; area d in the presence of false signals on the input bus 5-1; region g when two signals are input to the input bus 5-2 instead of one.

 The present invention improves the quality of control by changing the circuit design. Moreover, the formation of the "Error" signal is provided in case of a violation of the order of the signals to the input buses, when several signals are received instead of one, if there is a constant signal on the input buses, and also if there are false signals on the input buses during the action of the next monitored signal or at the same time lack of signals on input buses.

Claims (1)

 DEVICE FOR CONTROLLING A PULSE SIGNAL SEQUENCE, comprising a multi-channel switch, the information inputs of which are connected to input buses, a pulse counter, a counting input of which is connected to the output of the multi-channel switch, a decoder whose inputs are connected to the outputs of the pulse counter and a second control group of inputs of the multi-channel switch that, in order to improve the quality of control of the sequence of alternating pulse signals, a comparison unit is introduced, and the second group of inputs dov is connected to the outputs of the decoder, the inverse output of the comparison unit is the output bus.

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