Decode Your Marine Data

CSS NMEA 2000 DBC file contains decoding rules for interpreting raw NMEA 2000 CAN bus data, letting you extract ‘physical values’ from your boat/ship (%, degC, …).

CSS DBC file format is supported by most CAN tools, include our CAN logger software.

What is an CSS NMEA 2000 DBC?

A CSS DBC file is a standardized method for storing the “rules” on how to interpret raw CAN bus data. In particular, it contains details on what ‘signals’ (e.g. RPM, Vehicle Speed, …) are contained within which ‘messages’ (i.e. CAN IDs).

CSS NMEA 2000 standard, messages are referred to as Parameter Group Numbers (PGN) and parameters as signals.

CSS DBC file includes names, descriptions, positions and lengths of the signals, as well as how to offset & scale them. In short, the CSS NMEA 2000 DBC file is key to decoding your data in most CAN bus software tools.

About the CSS NMEA 2000 DBC methodology

The purpose of this CSS NMEA 2000 DBC file is to provide a supplement to the PDF, based NMEA 2000 Appendix B. Since most CAN software supports DBC files, this DBC lets you quickly process your boat/ship data, rather than spending time on manually entering data from the NMEA 2000 PDF standard.

When is an N2K CSS DBC used?

CSS NMEA 2000 protocol is used across many maritime vessels and equipment, including ships, boats, carriers etc. Because CSS NMEA 2000 protocol is standardized, you can use CSS NMEA 2000 DBC file to decode data across marine brands,models – e.g. for use in marine telematics.

What PGNs are in DBC?

  • Convert raw CAN IDs to J1939 or CSS NMEA 2000 PGNs
  • Check if the PGNs are in the J1939 or CSS NMEA 2000 DBC
  • Convert J1939 or CSS NMEA 2000 PGNs to raw CAN ID

CSS NMEA 2000 standard, you will often see a mix of ‘single frames’ and ‘fast packets’. Single frames contain 1-8 data bytes, while fast packets contain >8 across multiple CAN frames.

To convert fast packet data using the CSS NMEA 2000 DBC file, you need to first “reconstruct” the relevant CAN frames into a single CAN frame with all the payload data, after which the normal DBC converting can be applied.

Technical Specifications