The synthesis of self-checking combinational devices on the basis of codes with the effective symmetrical error detection

The methods of fault-tolerant coding are often used in the designing of reliable and safety components of automatic control systems: both in the data transmission between system nodes, and at the level of hardware and software architecture.
The redundant coding is widely used in the management of combinational logic devices control. In this case, codes, which are oriented to the error detection rather than correction of this, are in use. Such features of codes make it possible to implement the checkable automation systems with acceptable redundancy, which does not exceed the redundancy in the situation of duplication using.
The paper highlights the method of the synthesis of self-checking combinational devices, which makes it possible to take into account the features of the source devices architecture, as well as the properties of error detection by redundant codes in solving the problem of the synthesis of technical means for diagnosis. The paper gives the basic information on the theory of the checkable digital systems synthesis on the basis of redundant codes with summation.
The basic stages of the analysis of the diagnosis objects topologies are determined with the selection of groups of outputs — groups of structurally and functionally symmetrically independent devices outputs. The formulas are given to determine the presence or the absence of a symmetrical dependence of the diagnosis object outputs. The example illustrating the calculation process is given. The main stages of the analysis of the redundant codes application in the error detection on the functionally symmetric dependent outputs are formulated. The algorithm of the synthesis of the self-checking combinational devices with taking into account the object of diagnosis structure features and the redundant codes properties is proposed.