This paper presents the design and construction of communication interfaces EUSART (Enhanced Universal Synchronous Asynchronous Receiver Transmitter) using the OSP / Satellite device. The technological product that integrates hardware, software and communications interfaces, was the result of a research project developed by the Colombian School of Engineering JULIO GARAVITO jointly with the company OSP LTDA and funded by COLCIENCIAS. This OSP / Satellite device reused equipment GPRS or also called units Automatic Vehicle Location: AVL, specifically TT8750 + of Skypatrol and SYRUS of DCT, which are used for locating and tracking mobile assets with cellular coverage, and they add a channel satellite backup via modem STX-2 Globalstar®, to ensure continuity in communication at any geographic area in Colombia.