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For advanced users desiring to develop their own custom software applications for communicating with Garmin® GPS products, this document describes the communication protocols required for transferring data including waypoints, routes, and track logs to and from Garmin GPS products via RS-232 or USB.
Download the Garmin Device Interface SDK
(Revision C last updated May 19, 2006)
Download the Garmin Proprietary Sentences Specification
(Provides information to NMEA users for application of the Garmin Proprietary NMEA Sentences)