Hardware Overview

The Calorimeter Trigger consists of a number of VME crates containing many different types of module.

• Eight preprocessor (PPr) crates: containing a CPU, up to 16 preprocessor modules (PPMs), one timing control module (TCM) and two preprocessor readout driver modules (PPRODs).
• Four cluster processor (CP) crates: containing a CPU, 14 cluster processor modules (CPMs), two common merger modules (CMMs) and one timing control module.
• Two jet/energy processor (JEP) crates: containing a CPU, 16 jet/energy modules (JEMs), two CMMs and one TCM.
• Two readout driver (ROD) crates: containing a CPU, up to 13(?) common processor readout driver modules (CPRODs), maybe one CERN BUSY module (if not in the TTC crate) and perhaps a TCM.
• One TTC crate: contain a CPU, one TTCvi module, one PPROD BUSY module, possibly one BUSY module for each of the two ROD crates (if not located within those crates) and one overall BUSY module (unless spare ports on one of the other BUSY modules are used for this purpose).

The trigger electronics chains will also contain

• Eight receiver crates (two for TileCal, six for LAr): containing up to 16 receiver modules and one SPACbus interface module. We will be responsible for the TileCal crates while the LAr groups will responsible for their receivers. However as the control of these systems is likely to be via a SPACbus controller (which can manage several SPACbus interface cards) sitting in some other crate, it may be worth having a single control crate for all eight receiver crates.
• One receiver control crate (perhaps): containing a CPU and a SPACbus controller module.

Additionally, in test setups, we may have:

• One or more DSS crates: containing a CPU and up to 6 DSS modules. In test setups, this crate may be combined with either the TTC crate or the crate containing prototype RODs.

The CPUs in each crate will be connected via a fast (or gigabit) ethernet switch. The system will be controlled by one or more workstations. The workstations will run various DAQ server processes (at least in standalone mode), monitoring, display and user interface programs.