Self-Checking Finite State Machines Based on Weight-Based Sum Codes and Properties of Self-Quasidual Boolean Functions

The computation control specific features at the outputs of finite state machines blocks using weight-based sum codes and the properties of self-dual and ‘close’ to them self-quasidual Boolean functions are described. The calculation control is proposed to be structured using several diagnostic parameters based on the principle of Boolean correction of signals from the tested object. An algorithm for additional definition of Boolean correction functions used at the stage of designing a self-check discrete device has been developed. The algorithm is based on two diagnostic properties that is: 1) Each Boolean vector at the output of the signal correction block in the embedded control circuit must belong to the set of code words of the weight-based sum code; 2) Each function describing the order of Boolean vectors formed at the outputs of the signal correction block must be self-quasidual. The proposed algorithm allows synthesizing a vast number of embedded control circuits with different performance parameters. Their practical use makes it possible to choose the best variation of the embedded control circuit according to one or another criterion. Different versions of building embedded control circuits have been estimated for a given number of inputs and outputs of the tested object. The proposed method is universal and can be used in combination with random uniform block codes. This, however, will require taking into account the code properties to ensure the generation of inspection tests for the embedded control circuit elements during the self-checking device operation. The results obtained can be used in synthesizing fault detection discrete devices.