RU1839257C - Device for interface between computer and peripheral device - Google Patents

Abstract

A device for interfacing a computer with an external device relates to computer technology. The purpose of the invention is to reduce the necessary equipment and expand the scope of the device. The device contains a status register, signal reception and control units, three AND elements, a data register, a request trigger, two data transmitter blocks and three 1-il amplifiers.

Description

The invention relates to computing

A device is known for interfacing two highways 1, comprising a group of information trunk transceivers, three synchronization trunk transceivers, a switch, three NOT elements, an AND element, a block of terminating resistors.

The disadvantages of the known device are its complexity, requiring a large amount of equipment, and a limited scope, due to the inability to exchange data on the initiative of an external device.

The closest in technical essence to the proposed one is a device for interfacing a computer with an external device 2, comprising a receiver unit, a transmitter unit, a transceiver unit, a status register, address counters, a control unit, a buffer memory, a data multiplexer, a control signal multiplexer , a divider and a bus driver for connecting to a group of computer control inputs, the information output of the transmitter node being the output of a device for connecting to a computer clock input, the first group is information of the input-output nodes of the transceiver unit forms a group of input-output devices for connecting to a group of computer information inputs / outputs, the second group of information inputs and outputs of the transceiver node, the first group of information outputs of the counter address a and the group of information outputs of the buffer memory form a group of inputs and outputs devices for connecting to the group of information inputs / outputs of an external device, the first information input of the control signal multiplexer is the input of the device for connections to the sync output of an external device, while the first to fifth information outputs of the receiver node are connected respectively to the installation input, the first to fourth inputs of the logical condition of the control node, the first output of which is connected to the information input of the transmitter node, the second output is from the control the input node of the transceivers, the group of information outputs of which are connected to the group of information inputs of the address counter and the group of inputs of the logical condition of the control node, the third and fourth the outputs of which are connected respectively to the read and write inputs of the counter, the second group of information outputs of which is connected to the group of address inputs of the buffer memory, the enable and write-read inputs of which are connected respectively to the first and second information outputs of the control signal multiplexer, the second and third information inputs which are connected respectively to the fifth and sixth outputs of the control unit, the first installation input of the status register is the input of the device for connecting to the installation output of the external device, information output of the buffer

5 memory is connected to the information input of the bus driver and is the output of the device for connecting and the information input of the external device, the first group of information inputs of the data multiplexer forms the group of inputs of the device for connecting to the group of information outputs of the external device, the first information output of the status register is the output of the device for connecting to the start input of an external device, the second information output of the status register is connected to the fourth information the input of the control signal multiplexer and is the output of the device for connecting to the read-write input of the external device, the third information output of the status register and the information output of the bus driver of the connection with the senior bit of the second group of information inputs and outputs of the transceiver unit, while the group information outputs of the transceiver node is connected to the group

0 information inputs of the status register with the second group of information inputs of the data multiplexer, the control input of which is connected to the fourth information output of the status register and with the control input of the multiplexer of control signals, the first information output of which is connected to the clock input of the divider, the input of which connected to the fifth information output of the status register, the read and write inputs of which are connected to the seventh and eighth outputs of the control unit, respectively, the ninth output which is connected to the control input

5 of the bus driver, the setting input of the status register is connected to the first information output of the receiver unit, the output of the divider is connected to the counting input of the address counter, the group of information outputs of the data multiplexer is connected to the group of information inputs of the buffer memory.

The disadvantages of this device are the large number of equipment used and the limited scope.

The purpose of the invention is to reduce equipment and expand the scope.

The object is achieved in that a device for interfacing a computer with an external device, comprising a status register, a block of control signal receivers, three AND elements, the status register outputs being the device status outputs to an external device, further comprising a register, a trigger. a data receiver unit and a data transmitter unit, three amplifiers, wherein the data input and the register clock are the data input and the write input from the computer of the device, and its output is connected to the data input of the data transmitter unit, the output of which of which is the data output to an external device, and the control input is connected to the output of the first element And, the input of which is connected to the first output of the state register and through the first amplifier with the control input of the device, a group of control inputs from an external device is connected to the data inputs of the receiver unit control signals, the control output and input of which are connected with the data output to the computer and the read input from the computer of the device, the data and status register control inputs are connected to the data and write inputs from the computer devices a, the inputs of the block of data receivers are data inputs from an external device, and the outputs and control input are connected respectively to the data outputs to the computer and the read input from the computer of the device, the write and read inputs from the computer of the device are connected to the inputs of the second element And, the output of which is connected with a trigger sync input, the installation input of which is connected to the first input of the third AND element and through the second amplifier with the request input from an external device, the output and the second input of the third AND element are connected respectively to the request output and the computer of the device and the first output of the trigger, the second output of which through the third amplifier is connected to the output of the request to the external device.

A diagram of the proposed device is shown in the drawing.

The device contains a data register 1, blocks 2.3 of data transmitters, a block 4 of control signal receivers, a state register consisting of state triggers 5, 6, a trigger 7 of the request, elements 8, 9, amplifiers 10, 11, 12 , element And 13, line 14 of the computer, line 15 of the external device. The outputs of triggers 5, 6 are

the status outputs of the device to an external device, the data input and the register input of register 1 are the data input and recording input from the computer of the device, and its output is connected to the data input of unit 2, the output of which is the data output to the external device, and the control input -connected to the output of the element And 9, the inputs of which are connected to the first output of the trigger 5 and through the amplifier 10 with the control input of the device5. A group of control inputs from an external device is connected to the data inputs of block 4, the outputs and control input of which are connected to a data output to a computer and a read input from the computer of the device.

0 The data and control inputs of triggers 5, 6 are connected to the data and write inputs from the computer of the device, the inputs of block 3 are the data inputs from the external device, and the control outputs and input are connected respectively to the data outputs to the computer and the read input from the computer of the device. The write and read inputs from the computer device are connected to the inputs of the element And 13, the output of which is connected to the trigger input of the trigger 7,

0 installation input which is connected to the first input of the element And 8 and through the second amplifier 11 input request from an external device. The output and the second input of the element And 8 are connected respectively to the output

5 of the request to the computer of the device and the first output of the trigger 7, the second output of which through the amplifier 12 is connected to the output of the request to the external device.

In the manufacture of data register 1, microcircuits of type 555IR23 were used. Blocks 2, 3 of data transmitters, block 4 of receivers and amplifiers 10, 11, 12 are made on microcircuits of type 531APZ. Triggers 5, 6 states are made on type microcircuits

5 531TM2, and trigger 7 requests - on the 555TM2 chips. Elements I, 8, 9, 13 are built on type 555LI1 microcircuits.

The device is designed to interface the input / output interface of a personal computer No. 9000 with the main types of system devices, mainly NMD, NML, ADCU (SCSI interface). At each moment in time, a computer and only one external device are logically connected.

5 Each external device is identified by a corresponding bit located on the data bus DVO - DV7. The device operates as follows. At the beginning of the computer, the DO line issues a reset signal, which is synchronized by the BW

sets trigger 5, from the output of which the reset signal RST enters the trunk of external devices. The interaction of a computer and an external device is characterized by the following states.

In the Free state, it is induced that the interface does not have an active device and that it is available for use, which is ensured by the absence of the SEL signal from the output of trigger 6 and the BUSY signal from the output of the external device.

The state of Sampling by the signal from the output of the computer is set to trigger 6, which generates a signal SEL, which is output to the corresponding trunk line of external devices, which selects an external device.

Then, the information transfer phase begins. The direction of transmission determines the I / O signal supplied to the input of block 4. and the read signal BR, read in the computer. Synchronization is provided by REQ and ACK signals. The transfer of information to the computer is initiated by the REO signal coming from an external device through an amplifier 11 at the input of the And 8 element and the installation input of the trigger 7. When the write signal arrives, the BW resets the And 13 element and the trigger 7 is set to one state. At the same time, from the direct output of trigger 7, the signal opens the And 8 element, generating a request signal in the computer. The computer generates a signal BR at the input of block 3 and reads the data.

The transmission of information to an external device is initiated by an ACK signal generated at the inverse output of flip-flop 7 and received from the computer by a recording signal. The data is written to

register 1,

When an I / O signal arrives, the And 9 element opens, the output signal of which controls block 2, through which data from the register is supplied to an external device.

(56) Copyright certificate of the USSR No. 1462329, cl. G 06 F13 / 00, 1989. USSR author's certificate No. 1401470, class G 06 F 13/00, 1988.

Claims (1)

The claims A DEVICE FOR COMMUNICATING A COMPUTER WITH AN EXTERNAL DEVICE, comprising a status register, a block of control signal receivers, three AND elements, the status register outputs being the status outputs of the device to an external device, characterized in that, in order to reduce equipment and expanding the scope, it contains a data register, a request trigger, two blocks of data transmitters, three amplifiers, the data input and the clock of the data register being the data input and recording input from the computer of the device, and its output is connected with the data input of the first block of data transmitters, the output of which is the data output to an external device, and the control input is connected to the output of the first element And, the inputs of which are connected to the first output of the status register and through the first amplifier with the control input of the device, a group of inputs external controls devices connected to data inputs 0 5 0 5 0 a block of control signal receivers, the outputs and control input of which are connected to the data output to the computer and the read input from the computer of the device, the data and status register control inputs are connected to the data and write inputs from the computer of the device, the inputs of the second block of data transmitters are data inputs from an external device, and the outputs and control input, respectively, with data outputs to a computer and a read input from the computer of the device, the write and read inputs from the computer of the device are connected to the inputs of the second element And, the output of which is connected to the clock the request trigger input, the installation input of which is connected to the first input of the third AND element and through the second amplifier with the request input from an external device, the output and the second input of the third And element are connected respectively to the request output to the computer of the device and the first output of the request trigger, the second output of which the third amplifier is connected to the request output to an external device. 35 40 45 50 55 # fifteen