SU1376086A1 - Device for built-in check of decoder - Google Patents

Abstract

The invention relates to computing and can be used in the design of reliable digital nodes. The purpose of the invention is to increase the reliability of the device. The device allows you to display the number of the selected output of the controlled decoder 14 using current-limiting resistors of the first group 1, key diodes

Description

WITH

with

about

00

but

groups 3, elements AND of the first group 6, elements NOT of the first group 4, multiplexer 10 and block 11 of the indication of the selected outputs. Incorrectly excited outputs of the monitored decoder 14 are detected and indicated by means of elements AND of the second group 7, multiplexer 10 and block 12 for indication of excessive excited outputs. In the absence of signals

At the output of the monitored decoder 14, the unexcited output of the decoder 14 is detected and indicated by the multiplexer 10j of the element OR 9, the current-limiting resistors of the second group 2, the elements of the first group 4 and the second group 5, the elements of the third group 8 and the display unit 13 for the unexcited outputs. 1 il.

one

The invention relates to computing and can be used in the design of highly reliable digital nodes.

The purpose of the invention is to increase the reliability of the device.

The drawing shows the functional diagram of the device.

The device contains groups 1 and 2 of current-limiting resistors, a group of 3 key diodes, groups of 4 and 5 elements of NO, groups of 6-8 elements I, element SHSh 9, multiplexer 10, block 11 for indicating selected outputs, block 12 for indicating extra excited outputs, block 13 display unexcited outputs, in addition, a controlled decoder 14.

Device for built-in control of the decoder works as follows.

The state at the exit of the controlled decoder 14 can be evaluated as follows; properly excited, properly unexcited, mistakenly excited (extra), mistakenly unexcited (unexcited).

If the signal at the output of the controllable decoder 14 is selected correctly, then the corresponding information input of the multiplexer 10 will have a zero signal (the other information inputs of the multiplexer 10 are disconnected from the device potential zero bus at this moment). At the input of the element of the first group 4, corresponding to the selected output of the controlled decoder 14, there will also be a zero signal, and at its output - a single signal. So on the first

the input element And the first group 6, where the selected output of the decoder 14 is connected, there will be a single signal. The second input of this element AND of the first group 6 from the output of the corresponding element of the NOT of the first group 4 also receives a single signal, which will cause the output of this element AND of the first group 6 of a single signal, which will be fixed by the display unit 11 of the selected outputs. The signal from the output of an open element AND group 6 enters through the element OR 9 at the inputs of the elements NOT of the second group 5, and zero signals from the outputs of these elements enters the first inputs of the elements AND of the third group 8 and closes the elements AND of group 8.. The first inputs of the elements And the second group 7, corresponding to the unexcited outputs of the controlled decoder 14, receives zero signals covering these elements. Element And of the second group 7, corresponding to the selected output of the decoder, is locked by the zero signal from the information input of the multiplexer 10. Thus, all elements of And of the second group 7 are also closed.

So, with the correct operation of the decoder, only the display unit 11 of the selected outputs shows the number of the excited output of the monitored decoder 14.

In the event that none of the outputs of the decoder 14 is energized, the inputs of the element OR 9 will have only zero signals, as a result of which, from the outputs of elements NOT of the second group 5, the first inputs of the elements AND of the third group 8 receive one

ny signals. Through the current limiting resistors of the second group 2, single signals arrive and the inputs of the NOT elements are of the first group 4, so that the outputs of these elements, besides that which corresponds to the unexcited output of the decoder, will have zero signals covering the corresponding elements of the third group 8. At the input of the element NOT of the first group 4, corresponding to the excited output of the decoder 14, there will be a zero signal defined by the information input of the multiplexer 10. From the output of this element NOT of the first group 4, a single signal will arrive , to the second input of the corresponding element AND of the third group 8, will open it and on the block 13 of the display of unexcited outputs, the number of the unexcited output will be shown.

In that case, if an extra output of the decoder 14 is excited, then a single signal from an incorrectly excited output will pass through the corresponding element AND of the second group 7 and will be displayed on the display unit 12 for indication of excess excited outputs.

Claims (1)

Invention Formula A device for embedded control of the decoder containing (all groups of current-limiting resistors 18 and a group of key diodes, the anode of each key diode of the group through the corresponding current limiting resistor of the first group connected to the corresponding information input of the device group for connecting to the corresponding information output of the monitored decoder that is different the fact that, in order to increase the reliability of control of the device, 15 jg 20 25 thirty 35 40 45 a PSHI element, a multiplexer, two groups of NOT elements, three groups of AND elements, an indication block of selected outputs, an extra excited outputs indication block and an unexcited outputs indication block are introduced, the first inputs of the AND elements of the first and second groups are combined and are the corresponding information inputs of the device connecting to the outputs of the monitored decoder, the cathode of each key diode of the group is connected to the corresponding information input of the multiplexer, the second input of the corresponding element And second The first group and the input of the corresponding element are NOT the first group, the outputs of the elements And the first group are connected to the information inputs of the display unit of the selected outputs and the inputs of the SH, the output of which is connected to the inputs of all the elements of the NOT second group, you are: - the turns of which are connected to the first inputs of the corresponding elements of the third group, the outputs of which are connected to the information inputs of the display unit of the unexcited outputs, the outputs of the NOT elements of the first group are connected to the second inputs of the corresponding elements of the first and The third group, the outputs of the elements And the second group are connected to the inputs of the display unit for the extra excited outputs, the output of each element is NOT the second group through the corresponding current limiting resistor of the second group is connected to the input of the corresponding element NOT the first group, the output of the multiplexer is connected to the zero potential bus of the device, the group the control inputs of the multiplexer form a group of inputs specifying the input actions of the device for connecting to the corresponding inputs; the inputs to the controlled decoder.