The ATLAS Local Trigger Processor (LTP)

The local trigger processor (LTP) receives timing and trigger signals from the central trigger processor (CTP), and injects them into the timing, trigger, and control (TTC) system of a subdetector front-end TTC partition. The LTP allows stand-alone running by using local timing and trigger signals or by generating them from memory. In addition, several LTPs of the same subdetector can be daisy- chained. The LTP can thus be regarded as a switching element for timing and trigger signals with input from the CTP or the daisy chain, from local input, or from the internal data generator, and with output to the daisy chain, to the TTC partition, or to local output. Finally, in combined mode, several LTPs can be connected together using their local outputs and local inputs to allow stand-alone running of combinations of different subdetectors.