Control and synchronization of the krypton calorimeter pipeline digitizer in NA48 experiment at CERN

We describe the part of the data acquisition system of the NA48 experiment (A precision measurements of ε/ε′ in CP violating; K0→2π decays), located on the SPS north area in CERN. This part controls the readout electronic for liquid krypton calorimeter based on the CPD modules. The CPDs are placed in 30 Fastbus crates chained into four Fastbus clusters, which are entirely galvanic isolated. The timing and synchronization of the readout process is provided by an 80 MHz clock train which contains various gaps of different size. For purpose of controlling the LKr readout, two types of Fastbus modules were designed and fabricated in high volumes: isolated clock fanout and optoisolated cluster interconnect.