How low-cost devices can help on the way to ALICE upgrade

Cheap, ready to install and simple to configure, minicomputer and microcontroller boards have been in use in ALICE for a few years for specific, non-critical tasks, like integrating the environment sensors network in the experimental site, and to monitor and analyse clock signals. These systems have also been installed inside the ALICE experiment, in the presence of magnetic field and radiation, and subjected to a functionality test. While the major part of these devices proved to work correctly even under the experiment conditions, finally some weaknesses were revealed, thus excluding this class of devices from usage in the production setup. They have also played a role in the realization of scaled systems for the ALICE upgrade. With them, we have been able to simulate the presence of Front-End cards which are not yet available, allowing to proceed in the development of the software framework, of libraries and interfaces, in parallel with the production and validation of the hardware components. Being off-the-shelf and available everywhere in the world, they can be installed in remote institutes and laboratories participating to the collaboration. Some of the systems have been realised by students and trainees hosted at CERN for short periods of time. As well as being cheap and easy to procure, they proved to be a great didactic tool, allowing young collaborators to realise a complete system from scratch, integrate into a complex infrastructure and get a hands-on approach to modern control systems.