With the surge of IoT devices, these systems must provide reliable services and make trustworthy decisions based on fast and accurate data analytics. Effective data analysis is crucial for IoT systems to make rapid decisions, gain insights, uncover hidden patterns, and interact with users and other systems efficiently. This work in progress aims to model connected devices as Parametric Timed Automata, allow them to share operating data on a blockchain and verify its good behaviour with this data. Operating data are seen as unknown constraints in Parametric Timed Automata and can be used to verify or improve models of connected devices, along with providing safety. We propose a framework to model simple connected devices, upload and download parameter through smart contracts and verify the safety of the produced behaviour.