SU1418714A1 - Multichannel priority device - Google Patents

Abstract

. The invention relates to automation and computer technology, in particular to the organization of interruption systems and data transmission control. The purpose of the invention is to reduce equipment. The device contains an element of AND 8 and channels, and in each channel - an element of AND 9, an element of OR-NOT 10, an element of OR 11, inverters 12 and 13. In the device, a polling signal a, arriving at the polling input of the next priority channel, propagates along interrogation circuit of channels until it detects a channel in which there is a request signal at the input. 1 il.

Description

The invention relates to automation and computing, in particular, to the organization of interruption systems and data transmission control. The purpose of the invention is to reduce equipment.

The drawing shows a functional diagram of the multichannel priority devices a. I The device contains channels 1-3, the demand inputs 4 of the device, the outputs 3 of the device resolution, the input 6 of the device survey, the signal output 7 | of the device, the element 8, and in each analog channel the element 9, the element OR NOT 1: 0 5 element OR 11 and inverters 12 and IJ3. -. - i The device operates as follows.

; IN THE INITIAL STATE, NO

from the request ignals (the levels of logic phgl on the inputs 4) and the signal interrogation (the level of the logical unit, on the input S) 5, as a result of which the outputs 5 will be output. the levels are logical zero, and at the signal output 7 - the level of the logistic unit, signaling about: the presence of request signals in the device. On the second entrances of the elements. And 9 in each channel enters the level of the l) unit from input 6 and up, 7 devices through the elements OR rij allowing reception of request signals to: the channel. .

When a request signal at the output of an element TJa AND 9 of this channel arrives in any channel, the logical unit level arrives at the inputs of inverters 12 and 13 and the first input of the element OR 1 1, resulting in the second input of the AND element 9 (. The level of the logical unit is maintained regardless of the signal levels at the second and third inputs of the OR 11 element. In addition, the request signal through the inverter 12 level of logical zero opens the first input OR-NOT 10 element, and closes the second input flies from input 6 Through the second inverter 13, the request signal by the logic zero level through the AND 8 element is output to output 7 and the third inputs of the OR elements 11 of all channels, preparing them for passing the interrogation signal. The appearance of the logical zero level at output 7 signals to the external system that at least one request in the device, as a result of which it issues a polling signal with a logic zero level at input 6 and further to the first channel, where elements OR NOT 10 and OR 11 are opened via the second inputs. If there is no request signal in the first channel, then OR one 0 will be closed at the first input by the level of the logical unit from the inverter 12, and the inputs of the OR element 11 will be logic zero levels, with the result that tJ of its output will also appear as a logical zero level closing the second input of the AND 9 element (which , the request signal to the first channel) and the incoming one to the polling input of the second channel

Thus, the signal of the interrogation, arriving at the polling input of the next priority channel, propagates through the interrogation circuit of channels, as described above, until it detects a channel in which a request signal is present at the input. In this channel, the polling signal through the element OR-NOT 10. is sent by the output at the output signal 5 in the form of a logic unit level, and the output state of the OR element 11 does not change t since its first input contains the level of the logical unit, resulting in further propagation the polling signal is terminated. Thus, if there is at least one request at the inputs 4 of the device, the interrogation signal from the input 6 of the device propagates along the interrogated circuit of channels in the absence of request signals at their inputs simultaneously blocking the reception of request signals into these channels. The polling signal propagation occurs up to the channel, at the input of which there is a request signal. By polling the elements of the SH-NOT 10 in this channel, the polling sigap changes the state at its output from the logical zero level to the logical one level, which corresponds to the selection of the highest-priority request signal. Since in all previous channels, which have a higher priority, the request inputs are disabled, and the polling inputs with a lower priority do not propagate the interrogation signal, requests in these channels will not pass to outputs 5 during 3

the total service time of this request.

After servicing the selected request, the request signal is removed, which leads to blocking the AND 8 and OR-NOT 10 elements of this channel and the distribution of the interrogation signal to the next channel if there is a request signal in at least one of the lower priority channels, which for maintenance. If there are no more request signals in any of the lower priority channels, then the logical unit level is set at the signal output 7, as a result of which And 9 elements in all channels will be ready to receive request signals.

The polling signal can be cleared by the external system prior to the end of the service request. In this case, after servicing the request, the external system issues the next polling signal only if there is a logical zero level at the output 7 of the device, which will signal to it that there is at least one request.

Formula of Invention

A multichannel priority device containing an AND element, a channel

14

In each canape, an OR-NOT element and a first inverter, the signal output of the device is connected to the output of the AND element, the polling input of the device is connected to the first input of the ILN-NOT element of the first channel, characterized in that, in order to reduce the equipment, each channel contains the element AND, the element OR, and the second inverter, each request input device is connected to the first input element AND of the same channel, the second input element AND each channel is connected to the output element OR its channel, the output element AND channel connected through the first inverter with the second input of the element OR NOT its channel and through the second inverter with the corresponding input of the element AND whose output is connected to the first input of the element OR of each channel, the second input of the element OR of each channel connected to the output of the element AND its channel, the third input of the element IL1 -1 of the first channel is connected to the device polling input of the third input of the ISh element of each channel, starting from the second one and connected to the output of the OR element of the previous channel.

Claims (1)

SUMMARY OF THE INVENTION A multi-channel priority device comprising an AND element, and, in each channel, an OR-NOT element and a first inverter, the signal output of the device being connected to the output 5 of the AND element, the device polling input connected to the first input of the OR-NOT element of the first channel, characterized in that, in order to reduce equipment, each channel 10 contains an AND element, an OR element, and a second inverter, and each request input of the device is connected to the first input of the And element of the same channel, the second input of the And element of each · 15th channel connected to the output of the OR element of its channel, the output of the element AND channel is connected through the first inverter to the second input of the OR element of its channel and through the second inverter with the corresponding input of the AND element, the output of which is connected to the first input of the OR element of each channel, the second the input of the OR element of each channel is connected to the output of the element 25 and its channel, the third input of the OR element of the first channel is connected to the polling input of the device ^ the third input of the OR element of each channel, starting from the second, is connected to the output of the elec- previous channel.