A method, in a distributed module of a real-time distributed system, used for operating synchronously with other distributed modules, comprising the following steps: i. determining (S1), when the present module (DSP0) is able to operate synchronously, at a synchronization start time that is unified with the other distributed modules (DSP1; DSP2; DSP3); ii. setting (S2) the present module's (DSP0) operate indication signal in a logic circuit (Req), based on the determining result, wherein the present module's operate indication signal is set to logic true when the present module (DSP0) is able to operate synchronously, otherwise, it is set to logic false; iii. deciding (S3) whether the present module (DSP0) is to operate synchronously, following a rule unified with the other distributed modules (DSP1; DSP2; DSP3), based on the present module's operate indication signal (Req) along with the operate indication signals (Req) in the logic circuit respectively set by the other modules (DSP1; DSP2; DSP3), wherein the rule unified with the other distributed modules (DSP1; DSP2; DSP3) comprises determining the logical AND of the present module's (DSP0) operate indication signal with the other modules' operate indication signals (DSP1; DSP2; DSP3) and wherein it is decided that the present module is to operate synchronously, when the result of the logical AND is true; otherwise, it is decided that the present module is not to operate synchronously, characterized in that , the method further comprises the step of : iv. resetting the operate indication signal of the present module in the logic circuit, at a synchronization end time unified with the other modules, said unified synchronization end time is indicated by an end interrupt signal which is provided by a counter controlling the present module, and the end interrupt signal is synchronized with the end interrupt signals provided for the other modules by other counters controlling the other modules. i. determining (S1), when the present module (DSP0) is able to operate synchronously, at a synchronization start time that is unified with the other distributed modules (DSP1; DSP2; DSP3); ii. setting (S2) the present module's (DSP0) operate indication signal in a logic circuit (Req), based on the determining result, wherein the present module's operate indication signal is set to logic true when the present module (DSP0) is able to operate synchronously, otherwise, it is set to logic false; iii. deciding (S3) whether the present module (DSP0) is to operate synchronously, following a rule unified with the other distributed modules (DSP1; DSP2; DSP3), based on the present module's operate indication signal (Req) along with the operate indication signals (Req) in the logic circuit respectively set by the other modules (DSP1; DSP2; DSP3), wherein the rule unified with the other distributed modules (DSP1; DSP2; DSP3) comprises determining the logical AND of the present module's (DSP0) operate indication signal with the other modules' operate indication signals (DSP1; DSP2; DSP3) and wherein it is decided that the present module is to operate synchronously, when the result of the logical AND is true; otherwise, it is decided that the present module is not to operate synchronously, <EOS>