Deployment and use of the ATLAS DAQ in the combined test beam

The ATLAS collaboration at CERN operated a combined test beam (CTB) from May until November 2004. The prototype of ATLAS data acquisition system (DAQ) was used to integrate other subsystems into a common CTB setup. Data were collected synchronously from all the ATLAS detectors, which represented nine different detector technologies. Electronics and software of the first level trigger were used to trigger the setup. Event selection algorithms of the high level trigger were integrated with the system and were tested with real detector data. The possibility to operate a remote Event Filter farm synchronized with the ATLAS Trigger and Data Acquisition System (TDAQ) was also tested. Event data, as well as detector conditions data, were made available for offline analysis.