SU886291A1 - Digital unit testing device - Google Patents

Description

one

The invention relates to telegraphy and can be used in automated control systems for communications equipment.

A device for controlling digital nodes is known, comprising a control unit connected in series, an input unit and a decomposition unit. test signals, as well as a series-connected comparison unit and a display unit, to the second input of which the second output of the control unit 1 is connected.

However, this device has a low reliability of control — and an insufficient depth of localization of faults, since it does not allow detecting the closure of the inputs of the tested node and short-term pulse signals.

The purpose of the invention is to increase the reliability of the control and increase the degree of localization of the malfunction of the upstream node.

To achieve this goal, a digital control unit containing a serially connected control unit, an input unit, a memory unit and a decomposition unit of test signals, as well as a serially connected comparison unit and a display unit, to the second input of which the second output of the control unit is connected, is entered series connected detection unit. fault register and stimulus register, the output of which is connected to the input of the tested node and the first input of the fault detection block, to

10 to the second input of which the first output of the test signal decomposition unit is connected, and the second output of the fault detection unit is connected to the first input of the comparison unit, to

15 to the second input of which the second output of the decomposition block of test signals is connected, while the second output of the memory block is connected to the input of the control unit, and the third and fourth

The 20 outputs of the control unit are connected respectively; to the control inputs of the stimulus register and the fault detection unit.

FIG. 1 shows the structural electrical circuit of the proposed device; FIG. 2 is a schematic of the fault detection unit.

The device comprises a control unit 1, an input unit 2, a memory unit 3,

30 block 4 decomposition of test signals. a comparison unit 5, an indication block B, a fault detection block 7 and a stimulus register 8. The malfunction detection unit 7 consists of AND-HE elements 9, triggers 10 and 11, valves 12, and contacts 13. The device operates as follows. at once. The test program from block 2 is written to block 3, the command information from block 3 is sent to block 1, which produces the commands Shift, Record, Feed, Poll. The test instructions are read from block E to block 4, where the expanded stimuli and the developed references are divided. On the Shift command from block 1, the expanded stimuli are sequentially coded into block 7 and written to the trigger 10. By the Record from block 1 command, the expanded stimuli are written to the triggers 11. The Feed command from block 1 opens the expanded stimuli through the gates 12 and the contacts 13 are fed. to the external contacts of the tested block 14. The reaction of the checked block 14 is fed to the contacts 13 and, at the command Poll from block 1, through the elements AND-HEN 9 is recorded in triggers 10. By the command Shift from block 1, the serial code from the inverse output trigger 10 after it is transmitted to the discharge blo 5, where a comparison with its deployed standards, poytupayuschi from control unit 4. Results GR razhayuts in block 6. Increased reliability is achieved by controlling the detecting circuit inputs checked forward unit 14 and short pulse signals as follows. Let it be required to check the absence of a closure between the inputs of the tested block 14. To do this, use the test command containing the code 0.1, ..., where the first input of the tested block 14 corresponds to O, the second input - the K-th output -. In block 4, this code is converted into expanded stimuli 0.1, ..., O, where the values of the signals at the input contacts are kept the same as in the original test command, and the output contact is marked with zero, and the developed standards are 0.0, ... where the input contacts are marked with zeros, and the signal value on the code contact remains the same as in the original test command. On the Shift command, the deployed stimuli are serialized in block 7, while O, 1, ... O are recorded in the triggers 10, O, on the Record command. The deployed stimuli O, 1 ..., O are recorded in the triggers 11. On the command Feed through gates 12 and contacts 13 to the next contacts of the tested block 14, the code 0,1, ..., 0 is received. In the absence of faults of the tested block 14, from its external contacts, 0.1 / ... comes to the contacts 13, which is fed to the second inputs of the AND-HE elements 9, and on the Poll command, the trigger 10 of the block 7 corresponding to the input commands in this test command The contacts of the tested block 14 are set in and the trigger 10, corresponding to the output contact of the tested block 14, is set to the state inverse to the code of the incoming signal. On the Shift command, the contents of the triggers 10 in the reverse code 0.0 ... goes to block 5, where the comparison with the deployed references 0,0, ..., occurs. If the codes match, block 5 generates a health signal. in the presence of a fault on the K-th output contact of the tested block 14, its external contacts send the code 0.1, ..., О to the contacts 13, which is transmitted to the second inputs of the AND-HE elements 9, and at the command Poll triggers 10 block 7 is written code 1,1, ... /. By the Shift command from the inverse output of the trigger 10, the reverse code O, O, ..., O is transmitted to block 5, where a comparison is made with the deployed references 0,0, ..., and a mismatch is found in the Kth order, corresponding to the K-th output contact of the tested block 14. In the case of a closure between the first and second inputs of the checked block 14 when applying 14 unrolled symbols / O, 1, ..., О at the first input contact of the tested block to the checked block 14 a signal appears, and a signal is stored on the K-th output contact of the tested block 14. Consequently, from the external contacts of the tested block 14. The contacts 13 receive the code 1.1, ..., which is transmitted to the second inputs of the AND-NE elements 9. When the Polling command is sent, the output of the AND-HE element 9 does not generate a signal trigger 10 remains in the state O, and a code 0.1, ..., 0 is written to the trigger 10. On the Shift command, the reverse code 1.0, ..., is transmitted to block 5, where, when compared with the deployed references 0.0, ..., a mismatch in the first bit is detected, it corresponds to the first input contact of the unit being tested 14. The presence of a short-term a pulse signal on the K-th contact leads to the appearance at the output contacts of the tested block 14 of the code 0.1, ..., O, which is fed to the contacts 13 and to the second inputs of the AND-HE elements 9.

When a polling command of sufficient duration is issued, the code 1.1, ..., is written in the triggers 10. and block 5 detects a mismatch in the K-th discharge, which indicates the presence of a pulse signal at the K-th contact of the tested block 14.

In the one-time mode, the proposed device allows the device to be stopped at a given test command or at the first test command in which a mismatch is detected, which makes it possible to check the state of the checked block 14 on any command of the test program.

In a cyclic mode, you can send any group of test commands to the tested block 14, remove any commands from the group, go to any command from the first command in which the mismatch occurred, and continue the test program in the natural order after the mismatch disappears. that is very important in the practical use of the device.

Thus, the proposed device allows detecting faults not only at the output, but also at the input contacts of the tested block 14, fixing short-term impulse signals, sending test signals to the output contacts of the tested block 14, which allows to control the nodes with high confidence

communication equipment and to increase the degree of fault localization.

Claims (1)

Invention Formula A device for controlling digital nodes, comprising a serially connected control unit, an input unit, a memory unit / - and a decomposition unit of test signals, as well as serially connected unit 0 comparison and display unit, v. The input of which is connected to the second output of the control unit, which is such that, in order to increase the reliability of the control and 5 increase the degree of localization of malfunctions of the tested node, sequentially connected block of fault detection and a register of stimuli, the output of which 0 is connected to the input of the tested node and the first input of the malfunction detection unit, the first output of the decomposition block of test signals is connected to the second input, and the second output of the fault detection block is connected to the first input of the comparison block, the second output of the test decomposition block is connected to the second input signals, while the second output of the memory unit is connected to the input of the control unit, and the third and fourth outputs of the control unit are connected respectively to the control inputs of the register of stimuli and There are no faults. Sources of information taken into account in the examination I. USSR author's certificate 498619, cl. G 06 F 11/00, 1974 0 (prototype).