SU1109931A1 - Start-stop receiver - Google Patents

Abstract

1. START-UP RECEIVER, containing a receiving-diaplex block, an OR element, a master oscillator, an input Noah an adapting block, the output of which is connected to the first input of a blocking trigger, characterized in that, in order to increase noise immunity, a pulse shaper is entered into it, the first output of which connected to the first input of the receiving-dialing unit, the second input of which is connected to the output of the OR element and to the first input of the pulse former, the second output of which is connected to the second input of the blocking trigger, the output of which is under for prison to the first input of the OR gate, a second input coupled to an output of the input matching unit, wherein the oscillator output is connected to the second input of the pulse shaper. 2. Receiver POP.1, characterized in that the pulse lighter contains two Counters and an element AND whose output is connected to the first input of the first counter and to the first input of the second counter, the second input of which is connected to the output of the first counter, and the output of the second counter with the first input of the element AND and is the second output of the pulse generator, the first output of which is the output of the first counter, the second input of the element AND is the first input of the pulse generator, the second input of which is the second CO th input of the first counter. from 00

Description

The invention relates to telecommunications and can be used in telegraphy. Known receiving start-stop device containing the input unit, the output of which is connected to the first. the input of the parcel registration unit, the output of which is connected to the first input of the protection unit, the output of which is connected to the input of the control unit and to the output of the start unit of the graphical apparatus, the input of which is connected to the output of the distributor, the additional output of which is connected to the second input of the protection unit The disadvantages of this device are design complexity and low noise immunity. The closest technical approach to the invention is a start / stop receiver containing a receiver-dialer unit, an OR element, a master oscillator, an input matching unit, the output of which is connected to the first input of lock 2 trigger. However, the well-known receiver has low noise immunity. The purpose of the invention is to increase the noise immunity. To achieve the goal, a start-stop receiver containing a receiving-dialing unit, an OR element, a pre-set generator, an input matching block, the output of which is connected to the first input of the blocking trigger, is inserted into the pulse shaper, the first output of which is connected to the first input of the receiving-dialed block, the second the input of which is connected to the output of the OR element and the first input of the pulse former, the second output of which is connected to the second input of the lock trigger, the output of which is connected to the first input of the PfflH element, the second input of the cat cerned input connected to the output of the matching unit, wherein the oscillator output is connected to the second input of the pulse shaper. In this case, the pulse shaper contains two counters and an element I, the output of which is connected to the first input of the first counter and to the first input of the second counter, the second input of which is connected to the output of the first counter, and the output of the second counter connected to the first input of the element I and is the second output of the pulse generator, the first output of which is the output of the first counter, the second input of the And element is the first input of the pulse generator, the second input of which is the second input of the first counter. Fig. 1 shows a structural electrical circuit of the proposed receiver; in fig. 2 - timing charts of the receiver; in fig. 3 structural electric circuit of pulse generator; in fig. 4 time diagrams of pulse shaper operation. Start-stop receiver contains input matching -block 1, lock 2 trigger, shaper 3 pulses, receiving and dialing unit 4, element OR 5 and master oscillator 6. Shaper forming 3 pulses contains first 7 and second 8 counters and element 9. 9. Input matching unit 1 contains the Schmitt trigger 10, the transistor 11, the optocoupler 12, the first 13, the second 14, the third 15 and the fourth 16 resistors and the first 17 and second 18 diodes. The receiving unit 4 contains the triggers 19. The start-stop receiver works as follows. In the initial state in the communication channel, the signal has a stop polarity, in which the current flows through the light-emitting diode of the optocoupler 12 in the conducting direction and the transistor of the optocoupler 12 is unlocked. When this current flows at the output of the optocoupler 12 through the circuit from the positive potential of the source E through the optocoupler 12, resistors 13 and 15 to the negative potential of the source E, creating a positive potential at the base of the transistor 11 relative to its emitter, and the unlocking transistor 11. On the open transistor 11 collector, a low level potential is generated (on the order of O, 7 V) which is converted by a Schmitt trigger 10 into a logic unit level signal. In the initial state in blocking trigger 2, one is written,; and the driver of 3 pulses is reset as a result of a single signal level from the output of the input matching unit 1 through the OR element 5. At the output of trigger 2, the start-stop receiver is formed zero potential signaling that there is no error. Before receiving the next code combination, a training impulse (FIG. 2e) arrives at the control input of the receiver-dialing unit 4, which sets the triggers 19 to the initial state. When a regular code combination arrives from the communication channel, its starting element (Fig. 2a) creates a potential at the input of the input matching unit 1, in which current flows in the conductive direction through diode 18, and the light emitting diode of the optocoupler 12 is blocked. As a result, the optocoupler transistor 12 is locked and current flowing through the circuit from the positive potential of the power source EJ through the optocoupler 12, resistors 14 and 15 to the negative potential of the source E3, the circuit from the zero potential of the power sources through diode 17 and resistor 14 continues to flow to minus potential of the source EJ and creates a potential of negative polarity on the diode 17 (on the order of minus 0.7 V), and a locking transistor 11. On the collector of transistor 11, a potential of high 5fn (about 4.5 V) is formed, which transforms Schmitt trigger 10 to the logic level signal zero. In the absence of interference in the communication channel (1, Fig. 2), the starting element of the next code combination in the form of a zero-level potential from the output of the input matching unit 1 enters through the element OR 5 (Fig. 2e) and the first input of the imager 3 pulses and starts it ( Fig. 2g). At the output of the pulse generator 3, a sequence of pulses is formed, the number of which is determined by the recalculation coefficient of the counter 8, recording in the receiving-dialing unit 4 information elements of a code combination (Fig. 26), which arrive at the second input of the receiving-dialing unit 4 through the OR element 5c the output of the input matching unit 1 In this case, the unit value of the information elements of the code combination corresponds to the stop field of the signal in the communication channel, and the zero value corresponds to the starting polarity of the signal. In the process of registering information elements of a code combination, the information in the receiving-dialing unit (4 is advanced by triggers 19 when each shift cycle arrives at the first input of the receiving dial-up unit 4 from the first output of the imaging unit 3 and the pulses. time ment 3, fig. 2a) at the second, the output of the end of the cycle of the pulse generator 3, a single potential is formed (fig. 2c), and the stop element (fig. 2a) of the code com-binning arrives from the COMMUNICATION channel 1 at this moment in time. the front of the signal of the end of the cycle in the blocking trigger 2 is registered the state of the communication channel at the moment of arrival of the stop element of the code combination.If there is no interference in the communication channel, then at the time the stop element of the code combination arrives from the communication channel at the output of the input matching unit 1 unit level and in blocking trigger 2 a unit is registered, i.e., the initial state of blocking trigger 2 after receiving the code combination does not change if there is no interference in the communication channel, the claim the code combination, resulting in the output of the start-stop receiver lock 2, the error signal remains in the zero state. During operation of the start / stop receiver, an electrical circuit may interrupt, interrupt, or impulse noise on any part of the information transmission path between the message source and the start / stop receiver, resulting in a single-pole or two-pole telegraph communication circuit (data transmission) the effective value of the signal is reduced to zero. Such a change in the signal in the communication channel, which leads to the formation of a starting parcel with a duration by the input unit of the receiver, is much longer than the start-stop cycle of the receiver, hereinafter referred to as a link in the communication channel. When a rupture occurs in a communication channel in the process of receiving code combinations by a start-stop receiver (21, Fig. 2), it is launched for the first time by a false start element and then functions as described above. At the same time, at the second output of the pulse generator 3, a signal of the end of the pulse generator cycle 3 (Fig. 2c) is generated, which is fed to the second input of the blocking trigger 2 And registers in it the signal state on the communication channel at the moment of arrival of the stop link. Since during this time trial, at the first input of the O2 trigger, the signal has a zero level, due to the presence of a gap in the communication channel, a single potential is formed at the output of the blocking trigger 2 (Fig. 2d), which is fed to the first input of the OR 5 element and artificially forms a stop element at its output (Fig. 2e). At the same time, the output signal of the stop polarity blocking trigger 2 prevents the launching of the driver 3 emuls over the entire duration of the rupture in the communication channel. The unit potential of the trigger output 2 blocking ki is fed to the output of the start-stop receiver as an error signal. In this case, the blocking trigger 2 remains in the single state until the stop polarity of the signal in the communication channel is restored. Thus, in the event of a disturbance such as an interruption in the communication channel, only one false code combination is received, accompanied by the Oshabka signal. The rest of the distorted code combinations are not accepted by the start / stop receiver. Start-to-stop reception also provides for the detection of errors caused by the acceleration of shsh lengthening the start-up cycle. When the receiver's start-stop loop is lengthened (3, Fig. 2) or when the start-stop loop of the transmitting device is shortened, the end-of-cycle signal (time instant L, fig. 2b) is formed after the stop element arrives from the communication channel (Fig. 2a) and falls from the moment the old parcel arrives at the next code combination or with its information elements of zero value. As a result, zero is registered in lockout trigger 2 and an Error signal is generated (Fig. 2d), as in the previous case, which indicates a code-distortion-correcting code pattern. 11 316 When shortening the start / stop cycle of the receiver (, Fig. 2a) or when the start / stop cycle of the transmitting device is lengthened, the end of cycle signal (time instant M, fig. 2b) is formed before entering the stop element of the code combination from the communication channel (Fig. 2a) and coincides with one of the zero information elements of the code combination. As a result, the Opshbka signal is generated, as in the previous case, which indicates the distortion of the code combination. After elimination of the malfunction, the blocking trigger 2 is set to the one state by applying to its third input a signal of the initial setting of the unit level. At the same time, at the output of the lockout 2 of the start / stop receiver, a zero signal level is generated, indicating that there is no error. The shaper 3 pulses works as follows. In the initial state, the signal at the first input has a single level, and the second synchronization input receives pulses (Fig. 4a) from the master oscillator 6. The output potential of element And 9 is formed by a single potential, resetting counters 7 and 8, and prohibiting their operation. At the output of the counter 7 with a variable conversion factor, a unit potential (Fig. 4k) is formed, which, together with the unit potential of the signal at the first input (Fig. Ae), forms the unit potential of the initial installation of counters 7 and 8, outputting: them in the initial state. In this case, the bits of the counter 7 (Fig. 4b, c, d, e) are in the zero state and do not switch. In the zero state are also the bits of the counter 8 with a variable conversion factor (Fig. Dz, and, k). The initial state of the counters 7 and 8 does not change until the zero level control signal (time moment L, Fig. 4e) arrives at the first control input of the pulse generator 3. As a result, at the output of element 9, a zero-level signal is generated (fig. 4g), allowing counters 7 and 8 to work. The pulses coming from the first input (synchronization) switch the bits of counter 7 (fig. 4b, c, d) and to its output. Through a time interval T, a first clock pulse is formed (Fig. Hell), which is fed to the first output of the driver 3 pulses and to the input of the first discharge of counter 8 with a variable conversion factor.

At the same time, time Tj, which determines the phase of the pulses at the first output, is equal to

Тз Т -0/2, where TC is the repetition period of synchronization pulses at the second input; n is the conversion factor of the counter 7. After the first clock pulse arrives at the input of the counter 8 with a variable conversion factor, its output produces the zero potential of the inverse output of the last bit (Fig. 4k) entering the input of the element 9. At the same time, the signal transition control at the first input of the pulse driver 3 in a single state, for example, under the influence of interference does not affect the further operation of counters 7 and 8, since the zero potential of the output of counter 8 with a variable conversion factor blocks the element Both 9 and its output maintain zero potential, permitting the operation of counters 7 and 8, regardless of the state of the signal at the first control input. Clock pulses from the output of the counter 7 are fed to the first output of the imaging unit 3 pulses. After placing the first discharge of the counter 8 of a predetermined number of clock pulses equal to the recalculation coefficient of the counter 8, a single potential of the end of the cycle is formed at the output of the last (time H, Fig. 4e), which is fed to the second output of the imager 3 pulses and at the same time coincides with the unit signal ypoBHei at the first input, control {time point H, FIG. 4e) and a unit potential is formed at the output of the element AND 9

reset counters 7 and 8 (time H, Fig. 4g), prohibiting their work. The shaper of 3 pulses provides protection against spurious triggering by a pulse whose duration is less than the specified one. When a mt pulse arrives, the zero level noise (time moment P, fcg 4e) at the first input (control) of the counter 7 is switched (Fig. 4b, c, d) under the influence of synchronization pulses. If during time T the signal at the first control input goes into a single state (time point P in Fig. 4e), then its state at the inputs of the element And 9 is identical with the one state of the output signal of counter 8 (time point P, fig 4k) with a variable n scaling factor and at the output of element L-9, a single latching of the initial installation of counters 7 and 8 is formed, resetting the bits of the counter 7 to the zero state (time P, Fig. 46, c, d). In this case, the first clock pulse is generated and the pulse shaper 3 is prevented from a false start. Introduction of new connections to the device, as well as a pulse former, allows to increase the noise immunity of the proposed start / stop receiver.

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Claims (2)

1. A START-STOP RECEIVER containing a receiving-and-receiving unit, an OR element, a generator, an input matching unit, the output of which is connected to the first input of the blocking trigger, characterized in that, in order to increase the noise immunity, a pulse shaper is introduced into it, the first output of which connected to the first input of the receiving-dialing unit, the second input of which is connected to the output of the OR element and to the first input of the pulse shaper, the second output of which is connected to the second input of the blocking trigger, the output of which is connected · a first input of the OR gate, a second input coupled to an output of the input matching unit, wherein the oscillator output is connected to the second input of the pulse shaper. 2. The receiver according to claim 1, characterized in that the Pulse former contains two Counters and an element And whose output is connected to the first input of the first counter and to the first input of the second counter, the second input of which is connected to the output of the first counter, and the output of the second counter is connected with the first input of the element And is the second output of the pulse former, the first output of which is the output of the first counter, the second input of the element And is the first input of the pulse former, the second input of which is the second input Vågå counter.