A system architecture uses at least two processors (2, 3), which jointly control a process and constantly compare their data with each other. A program complex which has been checked with respect to the possible errors, as well as a non-checked program complex, runs on one of the two processors (2). In order to rule out interference in the checked program complex by the non-checked one, the peripheral hardware (12) which interact with the checked program complex are provided with inhibit inputs (16), and the tested program complex, via the inhibit inputs (16), blocks the peripheral hardware (12) which are reserved for it before it gives up command to the non-checked program complex.