The data merger readout controller for the NA48 experiment data acquisition electronics

The NA48 experiment offers a four fold improvement in statistical and systematic error over earlier measurements of the magnitude of the direct CP (Charge-Parity) violation of the neutral Kaon system. This requires maximum event readout efficiency, controlled event building and fast monitoring of run time errors. The event data flow in particular must be sustained at 100 Mbyte/s. The Data Merger Readout Controller presented in this paper offers this facility at minimal production cost.