SU1705830A1 - Device for checking decoder - Google Patents

Abstract

The invention relates to automation and computing and can be used to control various decoders. The aim of the invention is to simplify the device. The device contains the encoder 1, the delay element 2, the element EXCLUSIVE OR 3. the integrator 4, the information inputs 5 and 6 of the device for connection to the corresponding information outputs of the monitored decoder, the control output 7 of the device. When the monitored decoder 8 is healthy, a pulse sequence with a period T m-r is formed at the control output 7 of the device, where m is the number of outputs of the group of monitored decoder 8, and g is the delay time in the signal passing through the encoder 1 and the controlled decoder 8. 1 Il.

Description

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The invention relates to automation and computing and can be used to control various decoders.

The purpose of the invention is to simplify the device.

The drawing shows a block diagram of a device for controlling a decoder.

The device contains encoder 1, delay element 2, element EXCLUSIVE OR 3, integrator 4, information inputs 5 and 6 of the device for connection to the corresponding information outputs of the monitored decoder and control output 7 of the device.

The device works as follows.

With a properly controlled decoder 8, suppose that at the initial moment of time its inputs are set to zero. At the output O of the decoder, according to Vits, a logical unit that excites the second input 1 of the encoder. At its output, a combination corresponding to one in the binary code appears, the logical unit at the output O disappears at the output of the decoder and appears at output 1, the input 2 of the encoder is excited, etc. Thus, autogeneration occurs in the device with a period of T m g, where m is the number of outputs of the monitored decoder, and g is the delay time of the signal passing through the encoder and the monitored decoder. Since r is sufficiently small, the frequency of the controlled decoder is close to the maximum, which corresponds to the most severe mode of operation. The magnitude of the delay element 2 delay T3 (m-1) r. After this time after the appearance of the signal at the first output, two single signals are present at the inputs of the EXCLUSIVE or 3 element, since after this time a signal of a logical unit appears. The element EXCLUSIVE OR 3 remains in the zero state. The integrator 4 serves to filter outliers at the output of element 3 due to an accidental short-term mismatch of the signals at the inputs of the element EXCLUSIVE OR 3 and can be an element OR with a capacitor connected at the input.

In case of a faulty controlled decoder 8, if there is a field constant at the input (output) of the device input 5 and after some time, the output 7 generates sequences of signals with a period That 0 + 1) t where j is the number of the output that is faulty and j + T is the input . At input 6, a logical zero is stored. In the event of a type failure (constant zero on output

decoder generation does not occur at all, at the inputs 5 and 6 and the output 7 of the device there is a logical zero. With the same fault, the last output at input 6 is zero and at input 5 and output 7

devices - generation with period T. For faults of type constant unit, i.e. the appearance of two or more units at the output of the decoder, the frequency of generation at the input 6 of the device increases and at the output

7, a pulse train also appears.

The invention allows to simplify the device and reduce the amount of equipment.

Claims (1)

Invention Formula A device for controlling the decoder, containing a delay element, an EXCLUSIVE OR element and an integrator, the output of the delay element being connected to The first input of the EXCLUSIVE OR element, the integrator output is the control output of the device, the input of the delay element is the first information input of the device for connection to the first information output of the monitored decoder, characterized in that, in order to simplify the device, it contains an encoder, and the 1st information The inputs of the encoder are (I) -m device information inputs for connecting to the (M) -m information outputs of the monitored decoder (2 1 t, where t is the number of information outputs of the decoder), the first information input of the encoder and the second input of the element EXCLUSIVE OR are connected to the main information input of the device for connection to the m-th information output of the monitored decoder, the output of the encoder is the information output of the device for connection to the information input of the monitored decoder, the output of the element EXCLUSIVE OR connected to the integrator input.