Smart light system: implemented using three STM32F4-Discovery Board, one LCD touch screen display for the user interface, three radio 802.15.4 for the zigbee communication, two photo-resistors and two strips RGB led. The system by means of photo-resistors placed on two slave boards detects and communicates to one master board the external brightness, such board sends back a new internal brightness value to adapt the total brightness to a level previously chose from the user. The internal light regulation is performed from salve boards through PWM signals. The implementation is realized under Erika (operating system OSEK/VDX compliant). The project also includes a design phase which consists of writing a Requirements analysis document.