Operational Experience and Evolution of the ATLAS Tile Hadronic Calorimeter Read-Out Drivers

TileCal is the central hadronic calorimeter of ATLAS experiment at Large Hadron Collider (LHC). It a sampling detector where scintillating tiles are embedded in steel absorber plates. The grouped forming cells, which read-out on both sides by photomultiplier tubes (PMTs). PMT digital samples transmitted to Read-Out Drivers (ROD) located back-end system for events accepted Level 1 trigger system. ROD core element electronics and it represents interface between front-end overall Data AcQuisition (DAQ) responsible energy time reconstruction, data synchronization, busy handling, integrity checking lossless compression. standard 9U VME board equipped with DSP based Processing Units mezzanine cards. A total 32 modules required entire detector. Each module has process from up 360 PMTs real less than 10 microseconds. commissioning RODs was completed 2008 before first LHC collisions. Since then, several hardware firmware updates have been implemented accommodate evolving Trigger DAQ conditions adjusted follow parameters. initial system, different operational experience during Run 2 presented.