The AgConnect Library API is designed to provide a communications tool for third-party applications to send commands to and receive data from STK. The AgConnect API consists of a set of functions that allow you to open a connection to STK, send Connect commands and receive data from STK in response, then close the connection when finished. The AgConnect API also provides a messaging function that allows you to print error and diagnostic messages in a variety of user-defined ways. If desired, you can override the messaging function and use it for your own purposes. With AgConnect, you need only provide the address of the STK product to which you wish to connect. Connect commands can be sent using a single function that returns any expected data, hiding the low level Connect protocol from the application.
Connect functional block diagram
STK Programming Interface 11.0.1