The Event Builder

Each ROC operates independently, reading and buffering its event fragments and then sending it via ethernet/FDDI to the event builder process on a Unix workstation. This process can handle multiple connections (up to 32 ROC's), and builds the event into the CEBAF common event format (see Appendix F). Event fragment numbers are checked to detect missing data. If synchronization events are implemented (through the Trigger Supervisor) then the event builder can automatically resyncronize the event stream flagging the previous section of "bad" events. The Event Builder supports spying on the data stream from multiple sources (i.e. copy an event from the stream), as well as inserting user specified events into the event stream, through a remote procedure call (RPC) interface.