SU1377856A1 - Priority device - Google Patents

Abstract

The invention relates to computing and can be used in multiprocessor systems to control the access of subscribers to a data transmission highway and other shared resources. The aim of the invention is to extend the functionality by serving several groups of requests in a cyclic mode. The device contains channels 1, and in the trigger 2, the elements AND-NOT 3, AND 4, ELI 5, AND 6, query inputs 7, polling input 8, reset input 9, resolution outputs 10. When a group of requests to inputs 7 is received, due to the connection of the inverse outputs of the AND 6 elements with the inputs of the lower elements AND 6, the resolution will be received at the output 10 of the request received in channel 1 with a minimum number, At the end of the service of the first request of the group, a polling pulse input 8, unserved requests are written to the corresponding: - 1cne triggers 2 and are subsequently serviced cyclically in the order of the age of channel number 1. Thanks to the inverse outputs of all terminals-S

Description

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Comm and 3 with the input of the element And 6 of the first channel and through the elements of OR 5 with the request inputs of the 7 remaining channels, the requests of the served group, re-received into the channels with small numbers, are served only after the end of the started cycle. With

1377856

From the inputs 7 of unserved requests of the first group and submitting to the other inputs 7 requests of the second group, a new service cycle begins, which can be similarly interrupted and the next one is started or the previously interrupted cycle is continued. 2 or

nor, which can be similarly interrupted and the next one is started or the previously interrupted cycle is continued. 2 or

one

The invention relates to computing and can be used in multiprocessor computers for priority service of subscriber requests for data transmission lines and other shared resources.

The aim of the invention is to expand the functionality of the device by cyclically servicing several groups of requests.

FIG. 1 shows a functional diagram of the proposed device; FIG. 2 is an example illustrating the maintenance of three groups of requests.

The device (Fig. 1) contains N channels 1 (N is the number of sources of requests). Each channel, except the first one, contains trigger 2, AND-NOT 3, AND 4 elements and SH-5 element. All channels also contain AND-6 elements. The numbers 7 indicate the device's request inputs, 8 is the polling input, 9 is the reset input, 10 is EXITS OF PERMISSIONS (FOR SERVICE).

The device can operate in two modes: priority and cyclic.

In the priority mode, the reset signal from input 9, all triggers 2 are set to the zero state in which they remain during the entire operation of the device. Polling signals to input 8 are not given in this mode,

Zero signals from the outputs of the flip-flops 2 close the elements AND-NOT 3, on the inverse outputs of which there is 1, coming to the second input of the element AND 6 of the first channel and to the second inputs of the elements. OR 5 other channels, and at the outputs of all the elements OR also 1,

Requests to the device 7 inputs come in the form of 1, the absence of the request is denoted by O. Due to the fact that the outputs of the sources of the requests at the device inputs 7 are connected to the outputs of the SHSh 5 elements of these channels, a logical operation is implemented on the connecting conductor I. Since the device’s priority mode of operation at the outputs of all elements OR 5 are generated 1, then

10 as a result of the mounting operation, and the first inputs of the AND elements 6 receive constant request signals.

(one

or o) developed by subscribers. If there are several requests (1), only the subscriber who is connected to the channel with the lowest number will receive a permission to serve (a single signal at output 10), because the signal O from the inverter 20 output of the AND 6 element of this channel and 6 channels from large rooms will be closed.

After servicing the selected subscriber, this subscriber removes (returns) his request ya corresponding to input 7. As a result, the subscriber who receives the request in one of the following channels will receive permission for servicing. If, in the course of such sequential servicing of requests, a request is re-submitted to a channel with a small number, then it will again (out of turn) receive a service permit, i.e. The priority mode of service requests is implemented. The positional priorities of the subscribers are taken into account: the priority depends on the channel number of the device to which

40 subscriber is connected.

To provide guaranteed service requests for all channels, the device has a cycle mode

This service is implemented as follows.

In the initial state, by the reset signal on input 9, all the triggers 2 are set to the zero position. Let an arbitrary group of inputs 7 receive requests in the form 1. At the same time, as in the priority mode, the service permission in the form 1 on one of the outputs 10 will receive a request received in the channel with the lowest number. At the end of the service, the subscriber generates a polling pulse, which is fed to the input 8 of the device. In channels that have requests for inputs 7, the polling pulse through elements of AND 4 will go to the synchronization inputs of trigger 2. In all channels that have requests (except for the channel currently being serviced), from the inverse outputs of elements 6, a single signal will be written to corresponding trigger 2, i.e. unserved requests of this group will remain at inputs 7 and will be written into the corresponding triggers 2.

A request at input 7 of at least one channel 1 and the unit state of flip-flop 2 of this channel open element AND-HE 3 of this channel and provide O at the outputs of elements AND-HE 3 of all channels in. This signal closes the element And 6 of the first channel. If the input 7 of the first channel was a request, then it served in the first cycle of the device, so closing And 6 of the element prohibits re-servicing the request of this channel.

In channels that have unserved requests at inputs 7 and triggers 2 in a single state, the outputs of the OR 5 elements produce 1, which does not affect the request signal of this channel. In channels-in which the triggers 2 remained in the zero state, the outputs of the elements OR 5 will be 0% which, in accordance with the operation Assembly And support at the first inputs of the elements AND 6 of these channels O, prohibiting the maintenance of a new group of requests that did not manage to be recorded in its triggers 2, but can appear after registration in triggers 2 unserved requests

sov of the group in question.

Service requests of this group in the channels having triggers 2 in a single state are performed in

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order of increasing channel numbers. At the end of the service of each successive request to the input 8 of the device, a pulse is sent, which, through the elements AND 4 channels having requests, goes to the synchronization inputs of the flip-flops 2 of these channels. In the channel that generated the single resolution signal at output 10, the zero signal from the inverse output of the element 6 is inserted into the trigger 2 of this channel, i.e. after servicing the request, the corresponding trigger 2 is zeroed.

Thus, the device implements a cyclic service mode for a group of requests. During the service cycle of the entire request group, new requests due to zero signals at the outputs of the elements OR 5 of the corresponding channels are zeroed and are not passed to the service. At the end of the service cycle of a group of requests. the triggers of 2 all channels will be zeroed out, and at the outputs of the elements AND-NOT 3 and OR 5 will be 1. The last. they allow the input of 7 new requests to inputs (Mounting And doesn’t return requests signals). A new service cycle of a new group of requests begins with the service of the request received on the channel with the lowest number, and the recording of the remaining unserved requests to the triggers 2.

The advantage of the proposed device is the possibility of cyclic maintenance of not one, but several groups of requests: the service cycle of this group of requests can be interrupted and the service cycle begins. neither the newly received request group or the service cycle of any of the previously interrupted service cycles of the request groups from the corresponding breakpoint is continued, as follows.

Let the device perform the service cycle of the S-th group of requests and in Ig X the triggers 2 record the un-served requests of the S-th group. To switch the device to service (S + 1) -th group of requests, all questions of the S-th group are removed from the corresponding inputs 7, and the other inputs 7 are asked (S + 1) -th group. In this case, the Ig-e elements AND-NOT 3 and 4 will be closed, and in Ij-x triggers 2 will remain unserved requests of the S-th group, which are not

they interfere with the service of requests (S + 1) -th group. Similarly, you can interrupt the started service cycle (S 2) -th group. If you interrupt the running request service cycle, remove requests from this group from inputs 7, and submit requests from any of the interrupted request groups to other inputs 7, then the remaining 2 serviced requests of the interrupted group stored in the corresponding triggers allow you to continue the maintenance cycle breakpoints.

The described procedure of cyclic servicing of groups of requests with interruptions and continuations of interrupted cycles is similar to the procedure of interruptions and continuations of the execution of programs in a computer.

FIG. Figure 2 shows an example of interrupting the service cycle of the first group of requests by the second group of requests for interrupting the service cycle of the second group of requests by the third group and then continuing the interrupted second and first request service cycles.

Claims (2)

Invention Formula The device has a priority containing N channels (N is the number of request inputs of the device), with i and channel (i - 2, N) containing the first AND element and a trigger, the device polling input is connected to the first inputs of the first I elements of the i – x channels X jifayw Jl I 2 3 4 S at 7 8 $ Iff five 0 50 five The moves of which are connected to the clock inputs of the flip-flops of the respective channels, characterized in that, in order to expand the functionality of the device by cyclically servicing several groups of requests, an AND element is entered into the first channel of the device, AND-NOT element, OR element and second element AND, the request input of the first channel is connected to the first input of the element AND of the first channel, the output of which is the channel resolution output, on the iM channel, the channel input and the output of the element OR through the connected to the first inputs of the element AND –NE, the second element AND and the second input of the first element AND, the inverse output of the second element AND connected to the information input of the trigger, the output of which is connected to the first input of the element OR and the second input of the element IS — NOT the inverse output of the element AND the first channel is connected to the second inputs of the second elements AND the i-th channel, the inverse output of the second element And the j-ro channel j 2., (N - 1) is connected to the (j + 1) -th inputs of the second elements AND channels from (j + 1) -th to the N-th, the outputs of the elements AND-HE of the ix channels through the installation And connected to the second inputs of the elements OR i-channels and the second input element AND of the first channel, the device reset input is connected to the reset inputs of the channel triggers ix, the output of the second element AND the i-ro channel is the output of the i-ro channel. wasp Jl