Patent ID: 8195946

Claim:
A method for checking coherence between data read from a first area of a memory of a microcontroller and an address of the read data, comprising: calculating, by a checking circuit, a current digital signature of the read data by means of a function also taking into account the corresponding address of the read data in the memory, the current digital signature being calculated based on the read data and the address used to access the read data in the first area of the memory, the checking circuit receiving from the microcontroller, for calculating the current digital signature, the address used for addressing the read data in the memory; and checking, by the checking circuit, the coherence between the current digital signature and a previously-recorded digital signature, wherein checking the coherence between the current digital signature and the previously-recorded digital signature, both based on the read data and the address used to access the read data, enables detection of a disturbance to an address decoder associated with the memory, wherein at least four groups of temporary storage registers are used to respectively store at least the data, their addresses, the recorded digital signatures extracted from the memory, and the current calculated digital signatures, and wherein a fifth group of temporary storage registers stores the addresses of the digital signatures recorded in the memory.