Report on Control/DAQ Software Design and Current State of Implementation for the Percival Detector

The Percival Collaboration is developing a high-speed,low X-ray energy detector capable of detecting single pho-tons while maintaining a large dynamic range of sensitivity.The increased brilliance of state-of-the-art Synchrotronradiation sources and Free Electron Lasers require imagingdetectors capable of taking advantage of these light sourcefacilities. The PERCIVAL ("Pixelated Energy ResolvingCMOS Imager, Versatile and Large") detector is being de-veloped in collaboration between DESY, Elettra SincrotroneTrieste, Diamond Light Source and Pohang Accelerator Lab-oratory.It is a CMOS detector targeting soft X-rays < 1 KeV, witha high resolution of up to 13 M pixels reading out at 120 Hz,producing a challenging data rate of 6 GiB/s.The controls and data acquisition system will include aSoftware Development Kit to allow integration with thirdparty control systems like Tango and DOOCS; an EPICS [1]areaDetector [2] driver will be included by default. It willmake use of parallel readout to keep pace with the datarate, distributing the data over multiple nodes to create asingle virtual dataset using the HDF5 file format for its speedadvantages in high volumes of regular data.This development project will culminate in a control andDAQ system capable of dealing with very high data rateswhile providing easy integration with site-specific controlsystems.This report presents the design of the control system soft-ware for the Percival detector, an update of the current stateof the implementation carried out by Diamond Light Source.