As a pathfinder for the JEM-EUSO mission, Mini-EUSO is a 25cm diameter telescope which is going to be launched and positioned inside the International Space Station (ISS) in 2018. The main scientific goal of this mission is the achievement of a state-of-the-art UV map of the Earth from a 400 Km altitude, with $\sim 6$ km of pixel spatial resolution, collecting data though a multi-level triggering system. The signal is collected with Multi-Anode Photo Multiplier Tubes (MAPMTs) and digitized by means of custom chips. The raw data moves then to a central system, the Zynq Board, where the trigger operates a data selection dividing different classes of events characterized by specific time scales. The acquired UV map will be used as discrimination threshold for the Extreme Energy Cosmic-Ray detection.