SU1267419A1 - Priority device - Google Patents

Abstract

The invention relates to computing, in particular, to devices for priority service of requests. The purpose of the invention is improving the speed of the device. The device contains a group of request triggers by the number of request sources, a group of priority registers, a group of comparison circuits, a group of AND elements, a clock generator, a counter, a control trigger, two AND elements, two OR elements, NOT elements, and delays. New in the device is the introduction of AND, NOT and delay elements, which allows the device to operate in two modes, taking into account the presence or absence of a service queue. This improves device performance when there is a service queue. 1 il. with

Description

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The invention relates to you: a numerical technique, in particular, to devices for the priority service of requests. The purpose of the invention is to increase the device’s likelihood by selecting the next service request during the service of the previous request. The drawing shows the structures on the device diagram. The device contains a group of triggers 1 request, a group of registers 2. Priority, a group of circuits 3 comparing the group of elements AND 4 (first 5 and second 6 elements OR, generator 7 TOV pulses, first 8 and second 9 elements And, counter 10, trigger 1 control, delay element 12, element NOT 13, device request inputs 14, reset inputs 15, groups of information inputs 16 of the priority code, device service demand output 17, device request outputs 18. The device operates as follows. In the initial state, query triggers 1, control 1 and m The sensor 10 is in the zero state, and priority is recorded in the priority registers 2. The highest priority request source has the smallest binary code. Requests from sources at random times in the form of pulses go to the device request inputs 14 and translate the corresponding the triggers 1 are in single states, preparing for the operation of the elements AND group 4. The further operation of the device depends on the availability of the service queue and the busyness of the maintenance device. If there is no service queue, then a single signal from the output of the element OR 6, the passage through the element 9 and 9, zeroes the counter 10 and four elements of the delay element 12 into the unit state trigger control 11, which opens the EI element. The clock pulses from the generator 7 begin to flow to the counting input of the counter 10. At the same time, the trigger I of the control prevents the control signal from the output of the element OR 6 from passing through the element 9, ensuring that the device operates reliably. At the outputs of counter 10, an increasing sequence of codes of binary numbers is formed, which are fed to groups of second inputs of comparison circuits 3, to groups of first inputs which are given priority codes from outputs of priority registers 2. When the codes of the outputs of the comparison circuit 3 are matched, single signals are generated that can appear at the inputs of the AND 4 elements only if the corresponding trigger of the query is in the single state. A single signal from the output of the AND 4 element arrives at the corresponding output 18 of the device, identifying the source of the request for maximum priority, through the OR element 5 transfers the control trigger 1I to the zero state, stopping the search for the source of the request for maximum priority, enters the output 17 of the device service demand and NOT 13 blocks the passage of the signal from the output of OR 6 through the element AND 9. The service device, under the condition of its idleness, begins the process of exchange of information with the selected source request and, which in this case sends a pulse signal at the input 15 of the device to the inverse input of a corresponding trigger of its request, transferring it to the zero state. This removes the lock to form a control signal when searching for the source of the request. having the highest priority. If a service queue has not formed at this time, the operation cycle is repeated. If there is a queue for service at the output of the element OR 6, there is an i single control signal. In this case, after identifying the source of the request with the highest priority and starting to service it, the blocking from AND 9 is removed, the signal from output-OR 6 goes to the input of setting the counter to the zero state and through the delay element 12 to direct input of control trigger 11, searched for the source of the request with the highest priority. The outputs I7 and 18 will form the corresponding signals.

After the end of the service of the source of the request, the service device proceeds to service the next source of the request without losing any time for identification.

Claims (1)

Invention Formula A priority device containing a group of request triggers according to the number of request sources, a group of priority registers, a group of comparison circuits, a group of elements AND, a clock generator, a counter, a control trigger, the first element AND, a first element OR, and the groups of inputs of priority groups of registers are the device priority code inputs, and the output groups are connected to the first input group of the corresponding group comparison circuits, the Equals which are connected to the first inputs of the corresponding elements AND group, the second input E connected to respective outputs of straight band request triggers group elements and outputs connected to outputs of the device requests the first inputs of the OR gate, whose output is connected to an inverted control input of the flip-flop, a first input of first AND pod674 .19 It is connected to the output of the clock pulse generator, and the output is connected to the counting input of the counter, a group of outputs connected to the second group of inputs 5 comparison circuits of the group, characterized in that, in order to increase the speed of the device, the second element AND, the second OR element, the NOT element and the delay element are additionally introduced, this is the first input of the second element AND connected to the output of the second element OR, the inputs connected to the direct outputs of the group request triggers, f5 the second input of the second element I is connected to the inverse output of the trigger) control, the third input of the second element I is connected to the output of the element KE, whose input is connected to the output 20, the service requirements of the device and the output of the first OR element, the direct output of the control trigger, are connected to the second input of the first AND element, and the direct input to the output 25 delay elements, the input of which is connected to the output of the second element AND, the installation input to the zero state of the counter, the inputs of the device request are connected to the direct inputs , Q triggers query Gruggl, inverse inputs of which are connected to the device reset inputs,