An instrumentation system which extends channel-based switched fabric architectures
to provide instrumentation signaling functions. The system comprises a chassis
including slots for receiving inserted modules. The chassis includes a backplane
which provides for inter-module communication, including a channel-based switched
fabric bus, such as the InfiniBand bus, and instrumentation signaling lines for
instrumentation signaling functions. The signaling lines may include a local bus
for adjacent slot communication of analog and/or digital signals, reference clock
lines for transmitting system reference clock signals to synchronize operations
of inserted modules, a trigger bus including trigger lines which connect to corresponding
slots to communicate trigger signals between the inserted modules for synchronizing
operations between the modules, and/or a star trigger bus including dedicated trigger
lines connecting a star trigger controller slot to each instrumentation slot for
communicating precision trigger signals generated by an inserted star trigger controller
module to the inserted modules.