SU1068926A1 - Device for mating subscribers with computer - Google Patents

Abstract

A DEVICE FOR PAIRING USERS WITH ELECTRONIC COMPUTER MACHINE (COMPUTER), containing a communication unit with a computer and the first communication unit with a subscriber, and a linear output; a computer communication unit is connected via a communication line to a first linear input of a first communication unit with a subscriber, the first linear output of which is connected through a communication line: to a linear input of a communication unit with a computer, which contains the first and second triggers, ; the first delay element and the first element NOT, the output of which through the load resistor is connected to the positive bus of the power supply unit of the communication unit with the computer, the output of the first trigger is connected to the first input of the first element And, the output of which is connected to the input of the installation of the second trigger The output of the interrupt signal of the device and connected through the first delay element to the input of the first element is NOT, the inputs of setting and resetting the first trigger, the second input of the first element AND and the reset input of the second trigger are co installation, prohibiting interruptions, interrogating the presence of interruptions, acknowledging a communication unit with a computer device, which is different, that, in order to increase the flexibility of the device operation, n-1 communication units with subscribers are inserted into it, and the first linear inputs and the output of each i-ro communication unit with the subscriber is connected respectively via a communication line to the second line output and the input of the (i-1) -th communication unit to the subscriber, and the second linear output and input of the i-ro communication unit the subscriber is connected, respectively, through the line sv - {zi with the first linear by the input and output of the (i + 1) -th communication unit with the subscriber, npri. By this, the computer communication unit additionally contains a current generator, the first transmitting and receiving optocouplers, the second element NOT, the first and second inputs of the first transmitting optron are connected respectively to the output of the first element NO and the negative bus; power supply unit of the communication unit with a computer, 1 the first and second outputs of the first transmitting optocoupler are connected respectively to the output of the current generator and to the linear output of the communication unit with a computer, and the input of the current generator is connected to the positive bus of the linear power source; A computer is connected to the first input of the first receiving optocoupler, the second input of which is connected to the negative linear input power source, the output of the first receiving optocoupler through the second power supply: is NOT connected to the third input of the first element enta And, the i-th communication unit with the subscriber contains the second receiving and transmitting optocouplers, the third and fourth elements are NOT, the second delay element, the second element AND, the element AND-NOT and the third, fourth, fifth triggers, and the synchronous input of the third O5 trigger is the input of the request for communication from the computer with the computer from the subscriber, the reset input of the fourth trigger is the input of the acknowledgment of the communication unit with the subscriber of the device, the unit output of the fourth trigger is the output signal of the communication enable signal from the computer of the device, zero output of the fourth trigger connection with the reset input of the fifth trigger, the sync input of the fourth figger is connected to the output of the NAND element and the reset input of the third trigger, the output of which is connected to the first input of the second element AND, the second input of which is connected to the output of the second receiving optocoupler and connected to the first input of the element AND NONE AND: through the second delay element with the second input of the element NONE, the third input is

Description

poro is connected to the output of the fifth trigger and to the input of the fourth element HE, the output of which is connected to the first input of the second transmitting optocoupler, the second input of which through the second load resistor is connected to the positive bus power source of the communication unit with the subscriber, the output of the second element I is connected to by the synchronous input of the fifth trigger, the first output of the second transmitting optocoupler is connected to the first linear input and the second linear output of the communication unit with the subscriber, the second output of the second transmitting optocoupler is connected to the second linear input House communication with the subscriber unit and the first input receiving the second photocoupler, a second input coupled to an output of the first linear connection with .abonentom.

The invention relates to digital computing and can be used to interface remote peripheral devices with an electronic computer (computer) using a two-wire communication line both for transmitting interrupt requests to a computer and for selecting one of their competitors in priority. .

A device for connecting subscribers to a computer is known, comprising a computer interface unit and a group of subscriber units combined by a three-wire communication line 11.

The drawback of the device is a large response time to an interrupt, since in the absence of competitors the peripheral device must wait for service for the whole period following the commands of the interrupt request. An increase in the frequency of the following interrupt request commands reduces the performance of the computer, since (; e most of the jvI-wide time is spent on executing scan commands.

The closest to the invention to the technical essence is a device for interfacing subscribers with a computer, containing communication units with a subscriber and a computer, interconnected by a two-wire communication line, the communication unit with a computer contains two triggers, the And element, the delay element and the first inverter with an external load resistor, the output of the first trigger is connected to the first input of the element I, the output of which is connected to the input of the installation of the second trigger, the output of which is the output of the interruption of the communication unit with the computer and connected through the delay element move the first inverter and the reset inputs of the first trig ger, the second input of AND gate and the reset input of the second flip-flop are input by the control unit communicating with a computer. When requesting a service, the external device sends a potential interrupt request signal to the computer and receives a response "t computer via the same line as a potential signal

The two-way exchange of these signals is carried out according to the asynchronous principle 2. A disadvantage of the known device is the impossibility of connecting to the two-wire communication line additional external devices of the subscriber.

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

This goal is achieved by the fact that a device for interfacing subscribers with a computer containing a communication unit with a computer and a first communication unit with a subscriber, the linear output of the communication unit with a computer being connected via a communication line with the first linear input of the first communication unit first subscriber with subscriber

5 the output of which is connected through a communication line with a linear input of a communication unit with a computer, which contains the first and second triggers, the first delay element and the first element NOT, the output of which through the load resistor is connected to the positive bus

0 of the source of the power supply of the communication unit with a computer, the output of the first trigger is connected to the first inlet. the house of the first e.pement And, the output of which is connected to the installation input of the second trigger, the output of which is the output of the device interrupt signal and connected via the first delay element to the input of the first Element NOT, the installation inputs and the reset of the first trigger, the second input of the first And element and the input the reset of the second trigger are respectively installation inputs,

0 prohibition of interruption, interrogation of the presence of an interruption, acknowledgment of a communication unit with a computer, p-I communication units with subscribers are entered, and the line input and output of each i-ro communication unit with the subscriber are connected via a second line respectively

5 linear output and input of the (i-1) -th communication unit with the subscriber, and the second linear output and input of the 1st communication unit with the subscriber are connected via a communication line with the first linear input and output - {i -f 1 ) th communication unit with the subscriber, with

This unit of communication with the computer additionally contains a current generator, the first transmitting and receiving optocouplers, the second element NOT, the pepper and the second inputs of the first transmitting

The optocouplers are connected respectively with the output of the first element and the negative bus of the power source of the communication block with the computer, the first and second outputs of the first transmitting optocoupler are connected respectively to the output of the current generator and to the linear output of the communication unit with the computer, and the input of the current generator is connected to the positive bus the linear power supply, the linear input of the computer communication unit is connected to the first input of the first receiving optocoupler, the second input of which is connected to the negative linear power supply bus, the output of the first About an optocoupler is NOT connected to the third input of the first element I via the second element, the i-th communication unit with the subscriber contains the second receiving and transmitting optocouplers, the third and fourth elements NO, the second element 3c; NOT and third, fourth, fifth triggers, the synchronization of the third trigger is the input of the request for communication with the computer from the subscriber, the reset input of the fourth trigger is the input of the acknowledgment of the communication unit with the subscriber of the device, the single output of the fourth trigger is the output of the enable signal ai with the computer device-, the zero output of the fourth trigger is connected to the reset input of the fifth trigger, the sync input of the fourth trigger is connected to the output of the NAND element and the reset input of the third trigger, the output of which is connected to the first input of the second element And, the second input of which is connected to the output of the second receiving optocoupler and with the input of the third element NOT, the output of which is connected to the first input of the element and through the second delay element to the second input of the element NAND, whose third input is connected to the output of the fifth trigger and to the input quarter HE element, the output of which is connected to the first input of the second transmitting optocoupler, the second input of which through the second load resistor is connected to the positive bus of the power source of the communication unit with the subscriber, the output of the second element I is connected to the synchronous input of the fifth trigger, the first output of the second transmitting Opt prna is connected to the first linear input and the second linear output of the communication unit with: the subscriber, the second output of the second transmission, its optocoupler is connected to the second linear input of the communication unit with the subscriber and to the first input of the second terminal a receiving optocoupler, the second input of which is connected to the first linear output of the communication unit with the subscriber.

FIG. 1 shows the block diagram of the proposed device; in fig. 2 is a functional diagram of a computer communication unit; in fig. 3 - a functional diagram of the block of communication with the subscriber.

A device for interfacing subscribers of a computer contains a block I St. zi with a computer and n blocks of 2 communication with subscribers. These blocks are interconnected by a two-wire communication line 3 containing a linear output 4 and a linear input 5,

The computer communication unit 1 has a setup input 6, an interrupt disable input 7, an interrupt presence input 8, a computer communication unit input 9 input, a line input 10, an output 11 of the interrupt signal and a linear output 12.

Unit 2 of communication with the subscriber has input 1E of communication request with a computer, input 14 of acknowledgment

the communication unit with the subscriber, the first 15 and second 16 line inputs, the output 17 of the communication permission signal from the computer, the first 18 and second 19 line outputs.

Unit I of communication with a computer contains (Fig. 2) two trigger 20 and 21, the element And 22, the element

5 23; delays, two elements 24 and 25, a current generator 26, transmitting the optocoupler 27, receiving optocoupler 28, a load resistor 29, a positive 30 and a negative 31 bus power supply of the communication unit t; Computers, 32 positive, 33 negative and 0 left 34 tires of a linear power source. The current generator 26 comprises, for example, a transistor 35 connected in a circuit with a common bus base, and a load resistor 36. The collector of transistor 35 is

5 by the generator output connected to the i p output of the transmitting optocoupler 27, the second output of which is connected to the linear output 12. Line input 10 is connected to the first input of the receiving optocoupler 28, the second input of which is connected to the negative

0 shnnaya 33 linear power supply.

Inputs 6 and 7 of block I are connected to the inputs of the installation and reset of the trigger 20, input 8 to the second input of the element 22, input 9 to the reset input of the trigger 21, and the output of the trigger 21 is connected to the output I.

5 Each communication unit 2 with a subscriber (FIG. 3) contains a receiving optocoupler 37, transmitting optocoupler 38, elements HE 39 and 40, delay element 41, element I 42, element 43, three Triggers 44-46, resistor 47 and positive bus 48 of the power source of the communication unit with the subscriber.

The trigger input of the trigger 44 is connected to the input 13 of the communication request, the reset input of the trigger 45 is connected to the acknowledgment input 14 of the communication unit with the subscriber, and the first output of the trigger trigger 45 is the output of the computer communication enable signal.

The first output of the transmitting optocoupler 38 is connected to the first linear input 15 and the second linear output 19 of the communication unit with the subscriber, the second output of the transmitting

6 optocoupler 38 is connected to the second linear input 16 and the first input of the receiving optocoupler 37, the second input of which is connected to the first linear output 18..

The device works as follows. som ..:

When one or several requests appear, the communication from subscribers on inputs 13, the device generates a generalized request signal and, if there is no prohibition from the computer, sends an interrupt signal to the computer through the block 1 on the output of the computer, temporarily halts the execution of the current task. communication with subscribers. At this point in time, the device prepares one of several initiative blocks of communication with subscribers (if there were several requests) to work by sending it a computer communication enable signal to the corresponding output 17, therefore the computer gpm, requesting the address of the subscriber Prepared for the exchange, receives an unequivocal answer indicating which subscriber will be exchanged. The process of transmitting a generalized request signal to a computer and issuing a response to one of the subscribers goes without the fate of a computer using a two-wire communication line 3. A computer communication unit 1 is designed to provide a connection between a computer and a two-wire communication line 3. In the initial state, the interrupt enable trigger 20 is set to a single position at the expense of the previously incoming signal at input 6. In one of the last cycles of execution of each current command, a positive impulse is received at input 8 from the computer. In the absence of interrupt requests at the output of the NOT element 25, the logical zero signal is maintained, the interrupt trigger 21 remains in the merged state. The interrupt signal at output I is absent, the element 24 is turned off and the current flows through the resistor 29 and the opt () LED 27. The transmitter of the transmitting optocoupler 27 is saturated, but its collector current is close to zero, i.e. in the absence of requests, all the transistors of the optocouplers 38 units 2 communications with subscribers are turned off. The TNC through the LED of the receiving optocoupler 28 is also practically Yaben zero, so a logical unit is formed at its output. Such a state is maintained until the moment when one or more service requests are received, as a result of which one or several optocouplers 38 are turned on and the resistance between output 4 and input 5 becomes low. In this case, the current from the current generator 26 flows through the saturated transistor of the optocoupler 27 into the closed line 3 and then through the LED of the optocoupler 28. Since the LED emits energy, a logical zero signal is generated at the output of the optocoupler 28 and a logical signal at the output of the inverter 19. units. When the next command is completed, the command from the control unit of the computer on the device's input 8 receives the interrogation signal for the presence of an interrupt, the element 22 triggers, the interrupt trigger 21 sets to one, the interrupt signal enters the computer from the output I. The same signal passes through element 23 delay and turns on the element NOT 24. The LED on the optro on 27 is turned off, the transistor of this optro does not go high, the LED on the optocoupler 28 turns off, the And element, 22 is blocked by a zero signal from the output of the HE 25. This hundred of block 1 is maintained. before the acknowledgment signal arrives from the computer at input 9. This signal comes either after the end of the data exchange with the subscriber, liipo in the process of exchange. After resetting trigger-i. 21, unit 1 goes into the described mode of checking the line 3 for the presence of a generalized Request Interrupt signal. Prohibition of receiving interrupt signals from subscribers is worn by setting trigger 20 through 7 to the zero state. The communication unit 2 with the subscriber operates as follows. The request signal of communication with the computer comes from the subscriber at the input 13 to the sync input of the trigger 44, setting this trigger to one state. If there is no current through the LED of the optocoupler 37, then a logical unit is formed at its output. In this case, And 42 sets the trigger 46 and the LED of the optocoupler 38 to turn on. If there are no competing requests, then the current coming from the first linear input 15 from block 1 passes through the transistor of the optocoupler 38 and turns on the LEDs of the optocouplers 37 "of its own and all the subsequent receiving optocouplers of communication units with subscribers located in the direction of unit 1. After the operation of the optocouplers 37 in the indicated units, these units are blocked, since the And 42 elements in them are closed with zero signals from the outputs of the corresponding optocouplers 37. The remaining blocks 2 of communication with subscribers are far from the unit 1 of communication with a computer, in comparison with the selected unit 2 also can not transmit to the computer signals of interrupt requests, i.e. the switched on transistor of the optocoupler 38 shunts similar circuits and none of Remote blocks do not receive a response signal in a given device operation cycle. In the selected block 2, the signal from the output of the element HE 39, if it has a sufficiently long duration (greater than the delay time of the element 41), interacts with a single signal from the output of the trigger 46 and turns on the element IS-NOT 43. The zero signal from the output of this element resets the trigger 44 , trigger 45 continues to collapse in a bridged state. After a time determined by the delay of the element 23 of the block J, the current from the current generator 26 ceases to arrive at output 4, therefore, all the LEDs of the optocouplers 37, which were previously turned on, are turned off. Turning off the LED of the optocoupler 37 in the power supply unit; Dites to turn off the element AND-43, i.e. to the formation of the output of the optocoupler 37 unit signal. In this case, the trigger 45 goes into one state and the trigger 46 is reset. The LED of the optocoupler 38 turns off. The signal from output 17 allows this subscriber to exchange information with a computer. The trigger 45 is reset by the input 14 either at the end of the exchange or in the process of information exchange, depending on the features of the computer software building and the design of the subscriber equipment.

With the simultaneous receipt of several. Signals on inputs 13 are possible “races associated with“ interception of current by blocks 2 located closer to block 1 (having a higher priority). However, this process cannot lead to an ambiguous choice of one of the initiative blocks of communication with subscribers.

Indeed, the time T for the existence of these races is limited by the response time of the blocking circuits made on the elements 39, 41 and 43, and since the delay of the element 41 is chosen longer than the time T, only one communication unit with the subscriber can be selected in the device.

The use of the proposed device allows either to save a single communication line or to increase the system performance by eliminating periodically executed subscriber scanning commands from programs.

Claims (1)

A DEVICE FOR INTERFERING SUBSCRIBERS WITH AN ELECTRONIC COMPUTER MACHINE (COMPUTER), comprising a communication unit with a computer and a first communication unit e by a subscriber, the line output of: a communication unit being connected to a computer being connected via a communication line with a first linear input of a first communication unit with a subscriber, a first linear output which is connected through a communication line: to the linear input of a communication unit with a computer, co-; which contains the first and second triggers, the first delay element and the first element NOT, the output of which through the load resistor is connected to the positive bus of the power supply of the communication unit with the computer, the output of the first trigger is connected to the first input of the first element And, the output of which is connected to the input of the installation of the second trigger, the output of which is the output of the device interrupt signal and is connected through the first delay element to the input of the first element NOT, the inputs of the installation and reset of the first trigger, the second input of the first element And and the input with dew second flip-flop are respectively setting inputs prohibition interrupt polling presence interrupt acknowledgment block ustroyst- connection with a computer. VA, characterized in that, in order to increase the flexibility of the device, η-l communication units with subscribers are introduced into it, and the first linear input and output of each i-ro communication unit with a subscriber are connected respectively through a communication line with the second linear output and input (i -— 1) -th communication unit with the subscriber, and the second linear output and input of the 1st communication unit with the subscriber are connected respectively through a communication line-j with the first linear input and output of the (i + 1) -th communication unit with subscriber this, the communication unit with the computer additionally contains a current generator, the first transmitting receiving optocouplers, the second element NOT, the first and second inputs of the first transmitting optocoupler are connected respectively to the output of the first element NOT and the negative bus of the power source of the communication unit with the computer,) the first and second the outputs of the first transmitting optocoupler are connected respectively to the output of the current generator and to the linear output of the communication unit with the computer, and the input of the current generator is connected to the positive bus. a linear power supply, the linear input of the computer communication apple is connected to the first input of the first receiving optocoupler, the second input of which is connected to the negative bus of the linear power supply, the output of the first receiving optocoupler through the second element is NOT connected to the third input of the first element And, i'th the communication unit with the subscriber contains the second receiving and transmitting optocouplers, the third and fourth elements NOT, the second delay element, the second element AND, the element AND NOT and the third, fourth, fifth triggers, and the sync input of the third trigger is the input of the communication request with the computer from the subscriber, the reset input of the fourth trigger is the acknowledgment input of the communication unit with the device subscriber, the single output of the fourth trigger is the output of the communication enable signal from the computer of the device, the zero output of the fourth trigger is connected to the reset input; · the fifth trigger, the fourth sync input (the trigger is connected to the output of the AND element and the reset input of the third trigger, the output of which is connected to the first input of the second element And, the second input of which is connected to the output of the second receiving optocoupler and the input of the third element NOT, the output of which is connected to the first input of the AND AND NOT element _; through the second delay element with the second input of the AND-NOT element, the third input of which is connected to the output of the fifth trigger and to the input of the fourth element NOT, the output of which is connected to the first input of the second transmitting optocoupler, the second input of which through the second load resistor is connected to the positive bus of the power supply unit of the communication unit with the subscriber, the output of the second element And is connected to the fifth input of the fifth trigger, the first output of the second transmitting optocoupler is connected to the first linear input and the second linear output of the unit with ides with the subscriber, the second optocoupler vyhbd second transmission line connected to a second input of the connection with the subscriber and to a first input receiving the second photocoupler, a second input coupled to the first output of the linear connection with the subscriber.