Patent ID: 6959400
Filing Date: 2005-10-25
Classification: G05B,G06F

Abstract:
1. A method for establishing consistent memory contents in a redundant system, having an active control unit and an inactive control unit, each having a processing unit with an interface unit and a memory, comprising: monitoring the memory of the active control unit by a memory monitoring module of the active control unit, the memory having address information relating to memory areas to which a write access has been performed and which is forwarded by the memory monitoring module of the active control unit to a copying device of the active control unit; synchronizing the address information supplied by the memory monitoring module of the active control unit by the copying device of the active control unit with a marking memory of the active control unit, in which the memory areas to which a write access has been performed are entered; sending data from the memory areas entered in the marking memory of the active control unit by the copying device of the active control unit by a link to the copying device of the inactive control unit, whereby corresponding bits are reset in the marking memory of the active control unit; storing the data received by the copying device of the inactive control device by the link at the address in the memory of the inactive control device at the same address stored in the memory of the active control device; and providing an interruption between two complete checks of the marking memory of the active control unit and the transfer of data to the memory of the inactive control device.