An integrated device including a functional circuitry and a built-in self testing circuit for executing a structured test on the functional circuitry is proposed. The functional circuitry includes means for receiving input test values from the built-in self testing circuit and returning output test values to the built-in self testing circuit. In the solution of the invention, the built-in self testing circuit includes a memory for storing starting test values and expected test values, means for generating the input test values according to the starting test values, and means for determining a result of the structured test according to a comparison between the output test values and the expected test values.