| 摘要 |
Identically structured processor boards operating in lockstep mode are frequently used for redundant systems. The deterministic behavior of all components comprised in the board, i.e. CPUs, chip sets, main memory, etc. i s the basic condition for implementing a lockstep system, deterministic behavi or meaning that said components simultaneously supply identical results if the components receive identical stimuli at the same time and if no error occurs . Deterministic behavior also requires the use of clocked interfaces. In many cases, asynchronous interfaces cause a certain temporal fuzziness in the system, preventing the overall behavior of the system from remaining synchronous. In order to nevertheless operate in lockstep mode, the inventio n relates to a method for synchronizing external events which are fed to and influence a component (CPU). According to said method, the external events a re temporarily stored by means of buffer elements and are then retrieved in a separate mode of operation of the component so as to be processed by an execution unit (EU) of the component, said component entering into said mode of operation in response to a condition being met, which can be or is predefined and reflects the number of executed instructions.
|
