SU1151943A1 - Interface for linking computer with telegraph communication line - Google Patents

Abstract

A DEVICE FOR COMMUNICATING A COMPUTER WITH A TELEGRAPHY COMMUNICATION LINE containing a trigger, first and second elements AND, first and second elements OR, first register, first decoder and pulse generator, the start input of which is the clock input of the device, the output of the pulse generator is connected to the clock input of the first register, the first stop input of the pulse generator is connected to the first input of the first element OR and the output of the first decoder, the inputs of which are connected to the information outputs of the first register, information the inputs of which are the information inputs of the device group, the single trigger input is the input of the beginning of the device transfer, and the single and zero trigger outputs are connected respectively to the first inputs of the first and second elements AND, the first input of the second element OR is connected to the zero input of the trigger and is input ending the transfer of the device, characterized in that, in order to expand the scope of application by increasing the number of modes of the device, a second register, a second section and a zad The information outputs of the second register are connected to the inputs of the second decoder and are information outputs of the device group, the output of the second decoder is connected to the second input of the second OR element, and is the output output of the device, the first and third inputs of the second OR element are connected respectively to zero and one trigger inputs, the fourth input of the second element OR is the input signal of the device Start, the output of the second element OR is the input of the device readiness signal, the output of the first The first register is connected to the second input of the first element I, the output of which is the information output of the device, the first input from the second element I is the information input of the device, the output 00 of the second element I is connected to the start input of the pulse generator and the information input of the second register which is connected to the second input of the pulse generator stop and is the ready output of the device symbol, the reset input of the second register is the input of the device received, the clock input of the second register tra connected to the output

Description

the pulse generator, the OR element is the device, the second output of the first OR element is connected via a delay element to the output request connected to the single input of the first input of the first switch. 1151943

The invention relates to computing technology and can be used, for example, to interface a computer (VM) with a telegraph unit (TA) in information processing systems received from remote subscribers. The purpose of the invention is to expand the scope by increasing the number of modes of operation. The drawing shows a structural diagram of the device. The device contains a subscriber station 1, consisting of a telegraph unit (TA) 2 and a calling device pa 3, connected to a line control unit 4, which contains an electrical line matching unit 5 and a line power source switching unit 6 with analog output 7, second register 8, first register 9, pulse generator 10, second decoder 11, delay element 12, first decoder 13, tr ger 14, second and first elements 15 and 16, second and first elements OR 17 and 18. The circuit also contains a telegraph line 19 connected to the linear input unit 4 and group 20 and 21 informational output-device inputs, outputs 22-24, respectively, symbol readiness, device symbol reception and request, inputs 25-28 symbol, received, device synchronization, device start and transmission end, input 29 from a linear power source (source not shown), output 30 of the device’s ready signal, input 31 of the line ready signal, input 32, information output 33. Line control unit 4 serves to electrically match telegraph line 1 signals 9 communications and signals of logical elements of the proposed device. Receiving elements of node 5 react to changes in the load circuit of the telegraph apparatus and when increasing the magnitude of the currents in the telegraph line, the Ready Line signal appears at input 31. When the Device Ready signal is sent to unit 4, node 6 switches the power source, resulting in node 5 changes the polarity of the current flowing in the telegraph link 19. Node 5 consists of receiver amplifiers, transmitter amplifiers and isolating elements. As node 6, for example, an electromechanical polarized relay or its electronic analog can be used. The device works as follows. Assume that the subscriber station 1 works with a computer (VM) connected to the inputs and outputs 20-28. In the process of information exchange between the subscriber station 1 and the VM, the following modes of operation of the device are possible: input of information into the VM; information output from VM; interruption of local processing mode initiated by VM. In the initial state of the device (the installation circuit is not shown), the trigger 14 is in the zero state, the registers 8 and 9 are reset. In this state, a high-omnibus loop of ringing device 3 is switched on in the circuit of the telegraph line 19 and the rest current flows through the line 19. TA motor disconnected from mains. When information is entered into the VM at the initiative of the subscriber on the calling device 3, the Call button is pressed, which leads to a high-impedance loop dropping and an increase in the linear current.

The increase in linear current excites the corresponding input amplifier - receiver of node 5 and through the element OR 17 to the output 30 the switching signal of the source of linear power supplies. In this case, node 6 commutes the polarity of the voltage of the linear supply source, as a result of which the direction of the current changes in the telegraph line 19. The calling device 3 detects a change in the direction of current flow and connects the TA motor to the electrical network. Thus, TA is ready to go.

When transmitting information from TA 2, the symbol code from the telegraph line 19 of communication through node 5 and element 15 arrives at the information input of the shift register 8 and at the start input of the generator 10, from whose output the pulses go to the clock input of register 8 and gates the recording of the received information .

After forming a specified number of cycles (for example, the 8th when working with the telegraphic 5th MKT-2 element code), the character code is written in register 8, the starting element being written in its highest bit, the following five bits are symbol, and in two lower bits there are two stop elements of the symbol.

From the output of the high bit of register 8, where the starting element of the symbol is written, the unit potential is input to the generator 10 stop input and the symbol reads out through the output 22 into the VM. Symbol readiness indicates the need to enter the symbol into the VM. tasks and proceeds to receive information from the telegraph. The code of the character from the register 8 in parallel form enters the outputs of group 20 in the VM. Upon receipt of the VM symbol via bus 25, a signal is received. The symbol is received, on which register 8 is zeroed.

After that, the device is ready to receive the next character from the TA 2. The command to complete the reception of information is a special package containing c in the message. The occurrence of this switch is fixed by the decoder 11, which at output 23 transmits to the high voltage a pulse signal of reception and excites the OR element 17, which generates a switch signal ({and linear power source and current direction change in the telegraph link 19). to the actuation of the ringing device 3, which connects the high-om cable to the telegraph line 19 of the communication and disconnects the TA engine from the mains. Information entered into the VM is completed.

When information is output from the VM, input 27 receives a pulse signal. The transmission starts, which is fed to the input of delay element 12, and through the OR 17 element to input of node 6 via bus 30. This signal switches trigger one to 14. Node 6 changes the field lness connection power source. This polarity change is recorded by the ringing device 3, which resets the high-resistance loop of the telegraph line 19 and connects the motor to the mains. The trigger 14 blocks the element And 15, prohibiting the reception of information from the telegraph line 19, and connects through the terminal 16 the output of the register 9 to the output 33.

After the delay element 12 is triggered, the OR element 18 generates a signal at the output 24 of the symbol request. The time setting of the delay element 12 is determined by the preparation time of the TA 2 for operation, including the start time of its electric motor. On a signal Request symbol at output 24 of the VM, outputs 21 in parallel receive a character code, which is accompanied by a signal Readiness of outputting a character at input 26.

The character is written into register 9, and the most significant and two of its least significant bits are written, respectively, of the start and stop letters of the telegraph code. After writing the symbol n, the register 9 triggers a generator 10 at the input 26, the pulses from the output of which advance the character code through the element 16 to node 5 and further to the telegraph line 19

After the character is output from the register 9, the decoder 13 triggers, according to the signal of which the generator 10 is stopped and the symbol 24 is generated at the output 24 of the signal. On this signal, the VM writes the next character to the shift register 9. To complete the transmission of information, the VM drives a pulse signal to the input 28. The end of the transmission, through which the trigger 14 returns to its initial state. In this case, the ringing device 3 disconnects the electric motor TA 2 from the electrical network, connects the high-frequency, loop and current in the telegraph communication line 19 reduced to a quiescent current value. At this mode, the output of information from the VM ends. Interruption of the local processing mode of the TA 2 on the initiative of the VM occurs as follows. VM generates at input 27 a signal to begin transmission, which is fed to the input of the element OR 17 and excitation gives output 30. Node 6 switches the bus 29 so. that a change in the direction of the current of the rest of the telegraph communication line 19 occurs. The calling device 3 resets the high-resistance loop, the TA 2 engine remains on. Further, the output of information from VM to TA 2 occurs similarly to the described output of information from VM. Thus, the device provides the ability to connect the telegraph apparatus through the communication line and its autonomous operation with the possibility of entering the reception mode by a signal from the computer. This allows the telegraph apparatus to be used for local processing without limiting the capabilities of the system.

Claims (1)

DEVICE FOR COMMUNICATING A COMPUTER WITH A TELEGRAPHIC LINK OF COMMUNICATION, containing a trigger, first and second elements AND, first and second elements OR, a first register, a first decoder and a pulse generator, the start input of which is the synchronization input of the device, the output of the pulse generator is connected to the clock input of the first register , the first stop input of the pulse generator is connected to the first input of the first OR element and the output of the first decoder, the inputs of which are connected to the information outputs of the first register, the information inputs are of which are the information inputs of the device group, the single input of the trigger is the input of the start of transmission of the device, and the single and zero outputs of the trigger are connected respectively to the first inputs of the first and second elements AND, the first input of the second OR is connected to the zero input of the trigger and is the input of the end of the transmission of the device, characterized in that, in order to expand the scope by increasing the number of device modes, a second register, a second decoder and a delay element, information The output outputs of the second register are connected to the inputs of the second decoder and are the information outputs of the device group, the output of the second decoder is connected to the second input of the second OR element and is the output end of the device, the first and third inputs of the second OR element are connected respectively to the zero and single inputs of the trigger, the fourth the input of the second OR element is the input of the Start device signal, the output of the second OR element is the input of the device ready signal, output from the first register nen / · {with the second input of the first element And, the output of which is the information output of the device, the first input of the second element And is the information input of the device, the output of the second element And is connected to the start input of the pulse generator and the information input of the second register, the output of which is connected to the second input the pulse generator shutdown is the ready symbol output of the device, the reset input of the second register is the signal input The device is accepted, the clock input of the second register is connected to the output of the pulse generator, the output of the first OR element is the output of the device request, the second input of the first OR through the delay element is connected to a single trigger input.