Distributed real-time computer system and time-triggered distribution unit
The invention relates to a time-controlled distribution unit ( 30, 31 ) for the distribution of messages in a distributed computer system for safety-critical applications. Said distribution unit is designed as a self-testing functional unit and comprises input channels ( 201 . . . 222 ) for receiving time-controlled periodic input messages from node computers ( 20, 21, 22 ) upstream in the data flow, and output channels ( 301 . . . 333 ) for transmitting time-controlled periodic output messages to the node computers ( 50, 51, 52 ) downstream in the data flow, a computer ( 40 ) being provided in the distribution unit and being designed to analyze, by means of a “simple” software, useful information contained in the input messages, and to decide whether output messages are output and, if so, which useful information is contained in the output messages.
1. A time-triggered distributor unit ( 30 , 31 ) for distributing messages in a distributed computer system for safety-critical applications, the time-triggered distributor unit ( 30 ), which comprises a self-checking function unit, the time-triggered distributor unit comprising:
input channels ( 201 . . . 222 ) for receiving time-triggered periodic input messages from node computers ( 20 , 21 , 22 ) that are upstream in a data flow;
output channels ( 301 . . . 313 ) for sending time-triggered periodic output messages to the node computers ( 50 , 51 , 52 ) that are downstream in the data flow; and
a comparator ( 40 ) configured to (i) analyze payload information contained in the time-triggered periodic input messages by using simple software, and (ii) decide whether the time-triggered periodic output messages are to be output and, if so, which payload information is to be contained in the time-triggered periodic output messages.
2. The time-triggered distributor unit of claim 1 , wherein, in a triple modular redundancy (TMR) configuration for masking a hardware fault occurring in a component upstream from the time-triggered distributor unit, at least one distributor unit ( 30 ) which has been expanded by the comparator ( 40 ) is equipped to make a choice using the time-triggered periodic input messages arriving from the node computers ( 20 , 21 , 22 ) which are upstream thereof.
3. The time-triggered distributor unit ( 30 , 31 ) of claim 1 , which is equipped to carry out time-triggered communication according to the TTEthernet standard.
4. A distributed real-time computer system comprising:
at least one time-triggered distributor unit according to claim 3 , wherein a redundant distributor unit ( 31 ) is provided in a TMR configuration for masking a failure of the at least one time-triggered distributor unit ( 30 ) that has been expanded by the comparator ( 40 ).