The aim of the embodiments is to provide a method for the secure processing of data, in which security is increased in relation to side channel attacks. To achieve this, operation codes for commanding co-processors are determined, for example for the bit-dependent transposition of register contents. The solution exploits the fact that as a result of the technical configuration for the co-processor, a shift of register contents, for example from register A to register B cannot be differentiated from the exterior from a shift from register A to register C.