Abstract:The Large Hadron Collider (LHC) at CERN is undergoing a major upgrade with the goal of increasing the luminosity as more statistics are needed for precision measurements. The presented work pertains to the corresponding upgrade of the ALICE Muon Trigger (MTR) Detector, now named the Muon Identifier (MID). Previously operated in a triggered readout manner, this detector has transitioned to continuous readout with time-delimited data payloads. However, this results in data rates much higher than the previous operation and hence a new Online-Offline (O2) computing system is also being developed for real-time data processing to reduce the storage requirements. Part of the O2 System is based on FPGA technology and is known as the Common Readout Unit (CRU). Being common to many detectors necessitates the development of custom user logic per detector. This work concerns the development of the ALICE MID user logic which will interface to the core CRU firmware and perform the required data processing. It presents the development of a conceptual design and a prototype for the user logic. The resulting prototype shows the ability to meet the established requirements in an effective and optimized manner. Additionally, the modular design approach employed, allows for more features to be easily introduced.