# Communicating with the DVL The DVL communicates via Ethernet or TTL serial. Both interfaces are active on startup. Incoming messages received on either interface are treated identically, first-come, first-served. Outgoing messages are sent on both interfaces simultaneously. Both interfaces can be used simultaneously, but we recommend you do not send commands on both interfaces. If using both for monitoring, use one for monitoring and the other for monitoring/controlling. Refer also to the user manual for CeruleanTracker, which is a Windows Application that may be able to manage all the communications for you. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.ceruleansonar.com/c/dvl-75/communicating-with-the-dvl.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.