SU661552A1 - Device for test diagnosis of logic units - Google Patents

Description

one

The invention relates to computing, in particular, to devices for testing control of logic circuits: TECs, computers, digital device circuits, LSIs, and so on.

Devices for testing the operation of logic circuits are known, comprising a control unit, a data input unit, an input and reference output unit, a monitored output unit, a switch, a comparison unit, control register units, a display unit 1, 2.

A disadvantage of the known devices is that the monitoring is performed only on the external outputs of the tested block with the issuance of general information on the indication is faulty, indicating only the numbers of non-matching outputs, which makes it difficult to localize the fault in the block being tested, the time for finding the fault is long and the accuracy of control low

According to the technical solution, the device closest to the proposed device is a test diagnostics of logic blocks comprising a data input unit connected to the control unit and through the first and second registers with the inputs of the switch and the information unit, the contact control unit connected to the output of the data input unit and to the display unit, and the unit of standards, the output of which through the comparator is connected to the first input of the comparison unit, the second input of which is connected to the output of the first register, the outputs of the control unit connected to the corresponding inputs of the first and second registers, the contact control unit, the switch, the comparison unit, the comparator and the display unit 3.

The drawback of the device is that it does not allow fixing all non-occurring sets of test sequences and those output contacts where errors are detected. This. The information is necessary for the implementation of known procedures for finding a fault location in the diagnostic dictionary. In addition, the accuracy of diagnostics is low when faults in the inputs of the Tested Device distort the input set supplied to it.

The aim of the invention is to increase the reliability of diagnosing the accuracy of finding a fault site.

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This is achieved by introducing into the device a counter, two memory blocks, an OR element and a fault isolating unit whose inputs are connected to the outputs of the control unit, the comparison unit and the second register, and the outputs are connected to the inputs of the first memory unit, the display unit, and a control unit, the output of the plug-in comparison unit at the first inlet of the OR element and through the first memory unit connected to the control unit to the input of the display unit, ONE out, which is connected to the output of the second memory unit, whose input is connected to the steps of the control and input data blocks, and the second input and output of the OR element are connected respectively to the output of the contact control block and to the inputs of the second memory block and the control block.

. „1.§Т. & 9 ensures the fulfillment of the set goal.

The drawing shows the block diagram of the device .....

The device contains a control unit 1, a data input unit 2, a task unit 3 consisting of the first 4 and second 5 rotors, a switch 6, a counter 7., a control block for contacts 8, a diagnostics block 9, a comparator 10, block electro II, Comparison Unit 12, Allocation Unit 13, Second Memory Block 14, Element OR 15, First Memory Block G6.5lock Indication 17.

The control unit ensures the initial installation, devices, control of data input, the implementation of check modes — automatic, address, until the synchronization of the operation of the entire device, and control of the display unit 17.

The control unit I provides the initial installation of the device, the control in the data stream, the implementation of the check modes — automatic, address, non-matching, the synchronization of the operation of the entire device, the control of the display unit 17.,:; - The data entry unit 2 provides input of data on the inputs and outputs of the monitored unit 9 into the state data register 5, vy; 11 contact contacts of unit 9 into the register 4, data about the number of the set read into the counter 7, data of the internal internal iOHTaKTQB bdok 9 in the control unit contacts 8.,

The register 4 6 is safe; it stores the information and the ID of the reference values of the logic levels at the external input and output Cnt.act.ax of block 9 on each set and outputs it to the switch 6, to the comparison block 12 and to the display block 17.

Register 5 provides for the storage of information about the input and output contacts of block 9 and the distribution of switch 6, to the fault isolation block 13 at the input and the display block 7 ... ,,, .., .. „:.„, „...: ,,

661552

Switch 6 provides for the conversion of test information about the states of the input contacts of the tested block coming from register 4 in discrete form into analog signals and switching these signals to the input contacts of block 9 by a command from the control unit 1.

Counter 7 provides the counting of test patterns read by data entry block 2 into register 4 or into control block of contacts 8, as well as a signal about the number of the dial into memory block 16.

The control unit of contacts 8 provides the switching AND comparison of the signal coming from one of the internal contacts of block 9 with the reference value of this signal coming from the data input unit 2, and also gives the result of the comparison to the input of the element OR 15 and to the display unit 17.

Ko.vinapaTop 10 provides an analysis of the parameters of input and output analog signals alternately at each of the contacts of the diagnosed unit 9, comparing them with the reference values of the parametpoB coming from the unit of standards II, as well as converting the signals of the tested unit from the analog form. into discrete-shaped signals and their output to the comparison unit 12.

The block of standards 1.1. Provides formari-bjHHe analog. reference signals as required by,. imposed on the parameters of block 9 and the supply of these s. signals to the comparator 10.

Comparison unit 12 provides a comparison of signals in discrete form, arriving from the comparator 10 and from register 4, alternately for each contact of block 9 and outputting the comparison results to the allocation unit 13, to the memory unit 14 and to the OR 15 element.

The malfunction allocation unit 13 provides detection of the mismatch between the reference and the output signals of my switch -,, I

rum 6 to the input of block 9, and also generates a signal of a mismatch at the entrance to the memory block 14 to the display unit 17 and to the control unit .1.

The memory module 14 provides for storing the numbers of the input or output contacts of the block 9, at which the signals do not coincide with the reference values, as well as providing information to the display unit 17.

The element OR 15 provides the assembly of the results of the comparison in monitoring the external and internal contacts of the block 9 and the generation of a signal about the discrepancy in the control unit 1 and in the memory block 16.

. The memory block 16 provides .curing TecfoBbjx to the burs at which it had

There is a mismatch. Signals on contacts

lock 9 with reference values, as well as

issuing information about the mismatched and current sets in the display unit 17.

The display unit 17 in accordance with the incoming signals provides an indication of the overall result of the control, the numbers of the unmatched contacts, the failure of the input contact, the numbers of the unmatched test sets, the reference information contained in the register 4 numbers of output contacts of the block 9.

To enter information into the device, punched tapes can be used, information on which is located in the following sequence: zone of input-output block definition 9, zone with the first test set for external contacts of the diagnosed block, zone with information and the state of the internal contacts of the block on the first set followed by the zone with. the second test set and a zone with information on the state of the internal contacts of the TEC for this set, etc. Each of the zones on a punched tape has service and information lines. In the service line, information on the assignment of the zone is recorded, and for zones with test sets, information on the number of the set. In the information line of the zone, each of the tracks corresponds to the contact number of the block under test and carries the corresponding information about this contact, input or output, logical zero or logical unit. The length of the zones depends on the number of contacts of the block 9.

In the automatic control mode, the BHCHJHHx contacts of the block 9 of the punched tape information are continuously read by the data entry unit 2. When reading the service lines of the next punched tape zone, the control unit 1 generates commands for entering information into the corresponding blocks of the device. After reading the next zone with information about dialing and recording information in register 4, control unit 1 generates a command according to which switch 6, according to information of register 5 and register 4, generates and switches the required analog signals to the inputs of block 9. Further, according to the commands from the control unit 1, a sequential polling of the block 9 is performed for all contacts. The commutator 6 compares the analog signal coming from the next contact of block 9 with the reference values of the signals, converts the result of the comparison into discrete form and outputs it to the comparison block 12, where it is compared with the reference signal for the contact received from register 4 In the event of a mismatch, the comparison unit 12 outputs a mismatch signal to the memory block 14, which stores the non-matching contact, into the allocation unit 13, which analyzes the input or output contact of the tested block esovpadenie on OR gate 15 which delivers a signal

the mismatch between control unit 1 and memory 16, which stores the set that caused the mismatch. If the input contacts of the block 9 do not match, information input does not occur, if a mismatch occurs on the input contact, the malfunction allocation unit 13 gives a short impulse to extinguish the information about the mismatched output contacts in the memory block 14, as well as a potential signal about the input mismatch to the control unit 1 and to the display unit 17. The output of information is stopped. The display unit 17 highlights the number of the input contact, on which the mismatch occurred, and the “INPUT FAILURE. After completing the entry of information, the display unit 17 provides an indication of the numbers of the output contacts on which the mismatch occurred, and the numbers of the test sets causing the discrepancy-. The principle of localization of a malfunction in the tested blocks, used in the device, is based on the fact that, based on the totality of the non-fading test sets, the faulty chip or group of microcircuits (3-4 chips) is determined using the diagnostic dictionary.

In order to further localize the fault within the microchip group, the internal contacts of block 9 (the outputs of the microcircuits in the block) are used.

For this purpose, in the control unit of contacts 8 there is an internal contact switch, made in the form of a chip adapter, which allows connecting any of the microcircuits of the tested block to any of the contacts, and an internal contact address switch that provides information about this contact from the array of information, coming from the data entry block. The reference and actual states of the internal contacts on each test set are compared in the control unit of contacts 8 and, in the event of a mismatch, the signal from the output of the block will go to the display unit 17 and to the input of the OR element 15, from which output the mismatch signal will go to the control unit 1 and memory block 16. The main mode and when monitoring the internal contacts of the scanned unit is automatic.

The modes of mismatch, address and split are auxiliary and are used when setting up and repairing the checked blocks.

Claims (3)

In the mismatch mode, data entry is stopped after the zone is read from the test set, causing a discrepancy on the contacts of the tested block. The display unit 17 provides complete information about the reference and actual conditions on the contacts of the diagnostic unit on this set. The address mode allows stopping data entry after reading a given test case. In stepping mode, data entry is stopped after reading each of the zones with information about the test set. The operation of the device in the listed modes is ensured by the control unit I, both when monitoring the external and internal contacts of the unit 9. Computers can be used to build control tests and compile diagnostic dictionaries. A device for testing diagnostics of computer blocks provides automatic: LI control of logic blocks both on way and on board. and on the input contacts, in detail, in automatic mode, the internal contacts of the unit (the outputs of the microcircuits) in the automatic mode. -. / -:; -.;,; "" ";"; .. and.; ":;;, The device allows the use of diagnostic dictionaries when searching for and localizing a fault. The invention The device for test diagnostics of logic blocks containing a data input unit connected to the control unit and through the first and second registers to the inputs of the switch and the display unit, the contact control unit connected to the output of the data input unit and the display unit, and the unit of standards , the output of which is Cherez cbm P ar ATOR UNDER to the driver for the comparison unit, the second output of which is connected to the output of the first register, the outputs of the control unit are connected to the corresponding inputs of the first and second Registers, contact control unit, switch, comparison unit, comparator and display unit, characterized in that, in order to increase the diagnostic accuracy and accuracy of the device, a counter, two memory blocks, an OR element and a fault allocation unit, whose inputs are entered into it connected to the outputs of the control unit, the comparison unit and the second register, and the outputs to the inputs of the first memory unit, the display unit and the control unit, the output of the comparison unit is connected to the first input of the OR element and through the first memory unit, connected to the control unit, to the input of the display unit, one of the inputs of which is connected to the output of the second memory unit, the input of which through the counter is connected to the outputs of the control and data input units, and the second input and output of the OR element are respectively connected to the output of the contact control unit and to the inputs of the second memory unit and the control unit. Sources of information taken into account in the examination 1. USSR author's certificate number 354415, cl. G 06 F 11/00, 1972. 2. USSR Author's Certificate No. 378852, cl. G 06 F 11/00, 1973 .. 3. Forward 2310342/24, cl. G 06 F 15/46, 1976, according to which a positive decision was made to issue an author's certificate. . and R .