Electronic Devices Hristijan Gjoreski, Mitja Luštrek, Matjaz Gams 8 2 2019 https://doi.org/10.6025/ed/2019/8/2/37-42 http://www.dline.info/ed/fulltext/v8n2/edv8n2_2.pdf In recent years the demand for intelligent systems that support the life of the elderly is increasing. In order to provide an appropriate support, these systems should constantly monitor the user with sensors. However, using sensors in reallife situations is a challenging task, mainly because of the constraints in the sensor energy consumption (battery life) and memory capacity for storing the sensors data. In this paper we present an example of a sensor communication protocol developed for the Shimmer accelerometers, so that they can be used in in real-life situations, i.e., constantly monitoring the user during a normal day. A custom firmware application is developed, which has several functionalities: real-time data streaming through Bluetooth, data logging into internal microSD card, sending the stored data to a Bluetooth-enabled device and detecting when the sensor is put on and off a charging dock.