An automatic correcting system was designed to be able to correct the programming exercises during a Massive Open Online Course (MOOC) about Microcontrollers, followed by thousands of students. Build around the MSP430G Launchpad, it has corrected more then 30'000 submissions in 7 weeks. This document provides general information about the system, the results obtained during a MOOC on the Coursera.org plateform, extensions done to remote experiences and future projects.