  The Compact Muon Solenoid (CMS) calorimeter regional trigger system is
designed to detect signatures of isolated and non-isolated electrons/photons,
jets, ?-leptons, and missing and total transverse energy using a deadtimeless
pipelined architecture. This system contains 18 crates of custom-built
electronics. The pre-production prototype backplane, boards, links and
Application-Specific Integrated Circuits (ASICs) have been built and their
performance is characterized.
