SU570897A1 - Device for preparing tests for repcatless composite circuits - Google Patents

Description

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The invention relates to computing, namely, to devices for monitoring troubleshooting in non-repetitive combinational circuits.

A device is known for obtaining tests of non-repetitive combinational circuits containing an evaluation unit, a switch of variables of a logic function, a switch of variables of elementary conjunctions, and an indicator of test sets. The control unit is connected to the commutators of variable logic functions and variable elementary conjunctions, the commutator outputs of the variable logic functions are connected to the same inputs of the variable conjunction commutator, whose load is the test case indicator 1.

The disadvantage of this device is that it is necessary to perform logical transformations in order to obtain a complete verification test, especially a minimal one, when it is necessary to solve combinatorial problems related to enumerating the number of conjunctions and finding the minimum matrix coverages.

It is also known the closest to the technical solution of the invention a device for obtaining tests of non-repetitive combinational circuits, comprising a control unit, a switch of variable logic functions, a switch of non-transitory elementary conjunctions, a switch of conjunctions, an indicator of test sets, the first output of the control unit connected to the control inputs of the switch variables of the logic function n of the conjunction commutator, the outputs of which are connected to the control inputs of the commutator of the variable elementary circuits nktsy, a first group of non-belt elementary conjunctions switch outputs connected to inputs of the first group indicator test kits 2.

The disadvantage of this device is that it is not possible to creep into minimal diagnostic tests that are among the diagnostic ones.

When monitoring combinational circuits, it is advisable to implement sets of testing tests, and when a failure is detected, the remaining sets, which together with the testing personnel, constitute a complete diagnostic test. This will reduce the time control.

The purpose of the invention is to expand the functionality of the device by obtaining complete testing tests that are included in the diagnostic test and have the shortest length.

This is achieved by the fact that a group of elements AND and an indicator of variables of a logical function are introduced into the device, the output of the control unit being connected to the control unit

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the input of the indicator of variables of the logical function, the second group of outputs of the switch of variable elementary conjunctions — with the group of inputs of the indicator of variables of the logical function and with the first inputs of the group of elements AND, the second inputs of which are connected to the outputs of the switch of variables of the logical function; the outputs of the group of elements AND are connected to the second group of inputs indicator test kits.

FIG. 1 shows a block diagram of the device; in fig. 2 - the basic electrical circuit of one of the possible variants of its technical implementation.

The device contains a control unit 1, a switch of 2 conjunctions, a switchboard of 3 variable elementary conjunctions, an indicator of 4 variables of a logical function, a switchboard of 5 variables of a logical function, a group of elements And 6, an indicator of 7 test cases.

The switch 2 of the conjunctions and the switch 5 of the variables of the logical function are connected to one of the outputs of the control unit 1, the indicator 4 of the variables of the logical function is connected to the other output of the control unit. One group of output buses of the switchboard 3 variable-elementary conjunctions are connected to the indicator inputs of the same name 7 test sets, the other — to the indicator inputs of the same name 4 variable logic functions, to the inputs of a group of elements And 6, standing between the outputs of the switch 5 variable logic functions and the inputs of the indicator 7 test kits.

Control unit 1 is a device made on switching elements, which are used to supply and relieve the voltage of the power source to the inputs of the switch 2, the switch 5 variable logic functions and the indicator 4 variable logic functions. One of the outputs of the control unit, connected to the inputs of the switch of the conjunctions and the switch of variables of the logic function, serves to supply voltage to the device for the duration of reading test sets, the other one connected to the indicator of variables of the logic function — to relieve the voltage when the device is brought into initial position.

The switch 2 of conjunctions is a set of switching elements corresponding to the elementary conjunctions with which the input of the switch 2 is connected to the corresponding output.

The switchboard of 3 variable elementary conjunctions is made matrix with two groups of output lines. The switching elements combined by the input buses correspond to the variable elementary conjunctions, and the combined output ujii-nami correspond to the variables of the logic function. Output wiring of one of the groups, connected to the inputs of the indicator 7 test sets, is connected to the inputs in the position of the switching elements, corresponding to the presence of variables regardless of their logic. The output wiring of another group connected to the indicator inputs 4 variables of the logic 5 function is connected to the inputs at the position of the same switching elements corresponding to the variables without inversion.

The indicator 4 variable logic function is made on the indicating elements

0 memory storing variable information upon receipt of all test sets. Each indicating element corresponds to a variable of a logic function.

Switch 5 variables of the logic function is performed on the switching elements corresponding to the variables of the logic function. In the on position of the switching elements, the input of the switch is connected to the corresponding output.

0 A group of elements And 6, the number of elements And in which corresponds to the number of variables of the logical function for which the device is designed, is open in the initial position and connects its own inputs to the outputs. With

5, applying voltage to the first inputs, the elements AND close and separate the outputs from the inputs.

The test case indicator 7 is a set of indicative elements corresponding to variables in the test sets, and the state of the elements corresponds to the state of these variables in the sets.

The device works as follows. In the initial position of the device, all switching elements are in the off state. To reset the memory elements of the indicator of variables of a logic function, it is necessary to remove the power supply voltage from the input of the indicator of variables of a logic function using the switching elements of the control unit. To obtain discontinuity sets using a switch, 3 variable elementary conjunctions are entered into the device.

5 is a logical function in a disjunctive normal form, and with the help of switch 5, variables of an inverse logical function are dialed. Then, using switch 2, one of the conjunctions is selected by including the corresponding switching element. When voltage is applied from control block 1, test set indicator 7 displays information about the state of variables in the set

5 breaks, and the 4 variables of the logic function variables - information about the variables controlled by this set. Next, the following conjunctions are selected by switching on the corresponding switching elements of switch 2, all variables or part of them are not controlled by the resulting sets. When power is sequentially supplied, the control unit reads information from the indicator each time.

5 test kits.

The selection of conjunctions and the receipt of sets of discontinuity occurs until there are no variables that are not controlled by the sets obtained. Functions all sets of discontinuity, which together control all variables of logic functions. These kits will be included in the test test. The device is then reset.

To obtain shunting sets using the switch 3 variable elementary conjunctions, the device introduces an inverse logic function in a disjunctive normal form, and with the switch 5 variable logic functions, variables of the logic function are dialed. Then, using switch 2, one of the conjunctions of the inverse logic function is selected by turning on the corresponding switching element.

When presenting the control unit 1 of control, indicator 7 of test sets displays information about the state of variables in the bypass set, and the indicator 4 of the variables of the logic function presents information about the control variables controlled by this set. Then, by turning on the corresponding switching elements of the switch 2, the following conjunctions are selected, all the variables of which or part of the variables e are controlled by the resulting sets. These non-set-controlled variables are read with indicators of 4 variables of the logic function. In the case of a sequential power supply, control unit 1 reads information from indicator 7 about test sets each time.

The selection of conjunctions and the collection of discontinuity sets are carried out until there are no variables of the logic function that are not controlled by the obtained bypass sets. These resulting kits will be included in the verification test.

Combining all fixed sets of rupture and bypassing, get a complete verification test. When searching for conjunctions in different sequences, one can get various complete testing tests.

When searching for conjunctions in the specified sequence, a complete testing test of the shortest length is obtained.

In order to crawl through the sets of a complete diagnostic test that contains any one of the testing tests, all the existing conjunctions of a logical and inverse logical function are sequentially searched.

FIG. 2 shows one of the possible variants of technical implementations of the device, designed for combinational circuits that implement logical functions in up to three variables.

As the number of variables of a logic function increases, only the number of elements of the device increases. The design and operation of the device does not change.

The control unit 1 is made on two buttons 8 and 9. When the button 8 is turned on, the voltage of the power source is removed from the device to bring it to its initial state. When the button 9 is turned on, the source is energized on the device while the test sets are being read.

The switch 2 conjunction has non-switches 0, 11, and 12, in the enabled state

which connects to the input of the corresponding output.

The switch 3 variable elementary conjunctions is made matrix. Switches 13–21 with fixed neutral rectum were selected as switching elements. In one of the included positions, both groups of outlet women are connected to the input wands, and in the other switched on position only wrinkles connected

with indicator inputs 7 test cases.

Indicator 4 variable logic function consists of electromagnetic relays 22-24, included in the scheme with self-locking, and combinational electric lights,

included in the chain of self-locking.

The switch 5 of the variables of the logic function is executed on the switches 25, 26 and 27, in the on state of which the corresponding outputs are connected to the input of the switch.

As elements And b used electromagnetic relays with normally closed and normally open contacts.

The indicator 7 test cases and the

a light panel on electric switching lamps 28, 29 and 30, corresponding to their variables in the test sets.

The advantage of the proposed device over the known one is that it allows to obtain the smallest testing tests, which are an integral part of diagnostic tests, as well as sets of complete testing tests, including the shortest length, ordered by the number of malfunctions that they detect. When controlling the circuit, this will reduce the control time.

F o rm} l and inventions

A device for receiving tests of non-repetitive combinational circuits containing a control unit, a switch of variable logic functions, a switch of variable elementary conjunctions, a switch of conjunctions, an indicator of test sets, the first output of the control unit connected to the control inputs of the switch of variable logical functions and a switch of conjunctions whose outputs are connected with the control inputs of the commutator of variable elementary conjunctions, the first group of the commutator output of variable elementary Onjunction is connected to the first group of inputs of the test set indicator, characterized in that, in order to extend the functionality, the device includes CI elements and And an indicator of variables of the logic function, the output of the control unit is connected to the control input of the indicator of the variables of the logic function, the second the group of outputs of the switch of variable elementary conjunctions is connected with the group of inputs of the indicator of variables of a logic function and with the first inputs of the group of elements AND, the second inputs of which are connected The switches with the switch outputs of the variables of the logic function, the outputs of the group of elements And are connected to the second group of inputs of the indicator of test sets.

P1 sources of information taken into account in the examination

1. USSR author's certificate No. 458830, cl. G 06F 11/00. 1974.

2. USSR author's certificate No. 388261 G 06F 11/00, 1971.

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