SU594497A1 - Interface - Google Patents

Description

one

The invention relates to computer technology and is intended for use in the technique of interfacing communication channels with electronic computers.

A device for interfacing is known, which contains a unit of matching with a computer, shift registers, synchronization blocks, transducer blocks, as well as blocks for analyzing starting and stop parcels.

Significant drawbacks of the device include significant hardware costs and low reliability of receiving parcels with impulse noise.

The closest proposed interface device containing a computer matching unit, connected bilaterally with a shift register, the first input of which is connected to the first output of the control unit and the input of the matching computer unit, the second output of the control unit and the control inputs of the channel selection unit and the distributor, the input of which is connected to the output of the shift register, the second input of which is connected to the first output of the synchronization unit, the input of the channel selection unit and the output of the distributor soy a dinene with the input of the converter unit; a memory unit connected by two-way communications with a control unit, a shift register and a synchronization unit connected by two-way communication with a control unit.

However, this device has a significant drawback, which consists in low reliability of reception with impulse noise, which, in addition to edge distortions, causes fragmentation of elementary parcels.

The aim of the invention is to increase the reliability of the device.

This is achieved by introducing zero and single sample counters, two comparison circuits, three AND elements, a marginal distortion norm register, two triggers, a front detection unit, the outputs of the channel selection block are connected to the first inputs of single and zero samples and inputs the edge detection unit, the output of which is connected to the first input of the first comparison circuit, the second and third inputs of which are connected respectively to the second output of the synchronization unit and the output of the edge distorted register, whose input is with the third output of the control unit, the outputs of the first comparison circuit are connected to the first inputs of the first and second I elements, the outputs of which are connected to the information inputs of the first trigger, the first n second outputs of which are connected respectively to the first input of the third element And and the second input of the second element And, outputs the second and third elements And are connected to the second and third inputs of the counters of single and zero samples, the outputs of which are connected to the information inputs of the second comparison circuit, the output of which is connected to a shift register input, a first output of the second flip-flop is connected by second inputs of the first and third elements AND, a second output of the second flip-flop is connected to the third input of the second element AND, the control input of the second comparison circuit is connected to the first output of the synchronization unit and the control inputs of which the ports with the third output of the synchronization block, the memory block are connected by two-way communications with the triggers, the marginal distortion norm register, the front registration block and the counter sam single and zero samples. The drawing shows a block diagram of the proposed device. It contains a transducer unit 1, a channel selection unit 2, a distributor 3, a front detection unit 4, counters 5, 6 zero and single samples, a comparison circuit 7, 8, a synchronization block 9, a marginal distortion register 10, triggers L, 12, elements And 13, 14, 15, shift register 16, control unit 17, computer matching unit 18, memory unit 19. The pairing device operates according to the principle of dividing the time between the connected channels, and the block 17 uses the sync pulses of the block 9 to select from the block 9 of the control word for this channel, control and write back the control word in sequence for each of the connected channels in such a way that during the duration of any elementary sending, discrete control of each channel is performed discretely at certain times, several times. By means of the control word for the selected channel, the device accepts a sign containing several elementary parcels, which through block I arrive at block 2. Then, in time, corresponding to the beginning of the next burst, block 17 samples the control word for block 19 from channel, the address of which also goes to block 2 to poll the state of the input channel of the corresponding channel. As a result of the survey, a single or null sample corresponding to a single or zero state of a parcel during this cycle is recorded in counters 6 or 5 and in block 4. Let the unit state accepted parcel be distorted so that there are boundary distortions in its first and second halves, the magnitude of which, within the limits of the duration of the parcel, corresponds to the fifth and the penultimate cycle, respectively, and the crushing pulse struck the center of the parcel. Then, during the first four control cycles of this channel, four zero samples accumulate in counter 5. In the fifth cycle, a single sample from block 2 enters the counter b beating block 4, at the output of which a signal appears, in this case an edge distortion signal arriving at the circuit 8. Circuit 8 compares the signal from block 9 with the signal 10, specifying the minimum mandatory interval for registering a parcel. If the recorded signal front in the first half of the parcel is in the zone of the minimum registration interval, then the sampling operation in counters 5 and 6 continues. Let the first registered front in the first half of the parcel be beyond the limits of this zone, then the signal from triggers 1 and 12, which are in the zero state, and circuit 8, through element And 14, reset the counters 5 and b and set it to one trigger 12. During the subsequent registration of the fronts in the range; 1x the duration of the first half of the parcel, indicating the presence of crushing, the reset of counters 5 and 6 is prohibited by a single state of trigger 12, i.e. the process of sampling continues. 8-stroke, corresponding to the center of the parcel, the block 9 realizes the installation of the trigger 11 and the reset of the trigger 12, the unit state of the trigger And corresponds to the registration of the second half of the parcel. Further, in the penultimate cycle, block 4 registers the next edge of the signal, corresponding in this case to the marginal distortion of the trailing edge of the message, and in scheme 8 the states of block 9 and register 10 are compared. If the detected signal edge is in the minimum required registration area, the collection samples in counters 5 and 6 continues. Let the registered front is outside this zone, then the signal from circuit 8 and trigger 11 through element AND 13 sets in one state trigger 12 and triggers And and 12, which are in one state, through element And 15 prohibit further counting of samples in counters 5 and 6. Block 9 per beat corresponding to the end of the burst, resets triggers 11 and 12, preparing them to register the next burst, shifts 16, preparing the position for recording the "next bit state, and controls the comparison of counter states 5 and 6 on mazh the critical principle in scheme 7. As a result of the comparison, the polarity of the received parcel is determined, the state of which from scheme 7 goes to register 16 for storage. After completion of gg of receiving several parcels, the sign code accumulated in register 16 is rewritten by block 17 to block 18. - The device for coupling favorably differs from the known one, since it accepts elementary parcels by measuring the edge distortions and registering a part of the parcel free from edge distortions, with the accumulation of discrete single and zero samples and the determination of the polarity of the parcel according to the majority principle, resulting in increased reliability, i.e. the probability of correct parcel reception the action is not only edge distortion, but also crushing. The total economic effect with a single installation of the proposed invention