SU773931A1 - Multi-channel switching device - Google Patents

Description

t

The invention relates to automation and telemechanics and can be used as a switch of digital information for bidirectional exchange with separated information sources transmitted over telephone channels.

Relay switches are known to contain relays, shift registers, control and blocking buses 1. O

The disadvantage of the device is low reliability.

In addition, multichannel switches are known, containing communication lines | 5, a switching and measuring unit, a counter, a trigger, logic elements, an information exchange unit, a pulse generator, and a control unit 2.20

The disadvantage of this device is the impossibility of bi-directional information exchange.

The purpose of the invention is to increase reliability and enhance functionality.

To this end, a multi-channel switch containing communication lines, a master oscillator, the output of which

connected to the first input of the element I, a counter, a trigger and an information exchange unit; blocks of receivers-transmitters are introduced by the number of channels, an ultiplexer, a demultiplexer and an NAND element, the bus I / O of the blocks of receivers-transmitters connected to the appropriate communication lines, and the outputs of the receivers are connected to the inputs of the multiplexers, the address inputs of which are connected to the inputs of the demultiplexer and the outputs of the counter, while the output of the multiplexer is connected to the information exchange unit and the first input of the NAND element, the second input of which connected to the trigger output and the second input of the AND element, and the output of the NAND element is connected to a single trigger input, the zero input of which is connected to the zero input of the counter, bus End of exchange and the output of the information exchange unit, besides another output of the latter is connected to the strobe input of the demultiplexer The outputs of which are connected to the inputs of the transmitters of the respective blocks of the receiver-transmitters, while the output of the element I is connected to the input of the counter.

The drawing shows the functional diagram of the proposed device.

It contains communication lines 1, master oscillator 2, counter 3, information exchange unit 4, receiver-transmitter blocks 5, multiplexer 6, AND-HE 7 element, trigger 8, And 9 element, demultiplexer 10, bus 11 End of exchange.

The device works as follows.

Communication line 1 is a two-wire telephone pair, information on which can alternately be transmitted in two directions, which is provided by blocks 5. Information on communication lines 1 is fed to the input of blocks 5.

In the initial state, the potential of logical 1 is present at all inputs of multiplexer b, since there is no information on the line. At the output of multiplexer 6 - the potential of logical zero. Information entering the information exchange unit is also missing. The trigger 8 is in the zero state, i.e. Potential 1 appears at the inverse output,

The address inputs of multiplexer b and demultiplexer 10 receive signals from the outputs of counter 3. The width, counter of multiplexer b and demultiplexer 10 are determined depending on the number of commutated channels. The counting pulses with the set; its generator 2 through the element And 9 is fed to the counting input of counter 3. Occurs, polling multiplexer b and demultiplexer 10. When information arrives on any of the inputs of multiplexer b at the time when the bus is selected at the address inputs multiplexer b appears positive potential When there are potentials of a logical unit at the two inputs of the NE-7 element, the potential zero appears at the output of the IS-NE element 7, which flips the trigger 8 to the one state, i.e. at the inverse of the trigger output 8, a potential of zero appears. This potential prevents the transfer of trigger 8 and the arrival of counting pulses at the counting input of counter 3. The counter stops. As a result, link 1 is connected to the output of multiplexer 6, and information from this line goes to exchange unit 4, and on demultiplexer 10, the bus to which

information from the information exchange unit 4 is received at the transmitter input of the same unit 5.

Information is exchanged in the selected communication channel until such time as a signal is received from the bus 11 End of the exchange. This signal will set trigger 8 and counter 3 to the initial state. The presence of information on any of the communication lines 1 will cause a repetition of the described actions.

Thus, the introduction of the 5 transmitter receiver modules, the multiplexer b, the NAND element 7 and the demultiplexer 10 allows for two-way exchange of the transmitted information and increase its reliability.

Claims (2)

1. USSR author's certificate number 362494, cl. H 03 K 23/255, 10.03.73. 2. USSR author's certificate number 588633, cl. H 03 K 17/04, 04/04/75.