In the realm of marine electronics, communication protocols play a crucial role in facilitating seamless data exchange and integration between onboard devices and systems. Two common protocols used in boats and yachts are NMEA 0183 and NMEA 2000. Understanding which protocol your boat uses is essential for compatibility, troubleshooting, and system upgrades. Please see Part 1of “Getting to Know NMEA 0183 vs. NMEA 2000” for a background into NMEA standards and the differentiating factors that each system has. Part 2 of “Getting to know NMEA 0183 vs. NMEA 2000” will discuss users interpreting the NMEA protocol differences and how to identify which system is in your boat.
The NMEA 0183 and NMEA 2000 standards not only differ in their technical capabilities but also in their accessibility and impact on system upgrades in the marine electronics industry. NMEA 0183, employing the RS-232 and RS-422 standards as outlined in Part 1 of "Getting to Know NMEA 0183 vs. NMEA 2000," is relatively open and straightforward to develop for, making it a popular choice for a wide range of applications and developers.
In contrast, NMEA 2000, which utilizes the J1939 standard, is much less open to the public. It is a proprietary system that can be more challenging and costly to develop for due to licensing fees and the need for specialized knowledge of its complex network structure, including its use of a CAN bus system, Parameter Groups (PGs), and standardized messages. This proprietary nature tends to benefit marine manufacturers by allowing them to control the development and integration of new devices and systems more tightly.
While the advanced capabilities of NMEA 2000—such as enhanced real-time monitoring, diagnostics, and control—offer advantages for more integrated and efficient systems, these benefits are often offset by the barriers to entry for smaller developers or hobbyists. This exclusivity supports the interests of established marine manufacturers who can afford the investment in development and who benefit from the reduced competition in the marketplace, contrasting sharply with the more developer-friendly and widely adopted NMEA 0183 standard.
The proprietary nature of the NMEA 2000 standard has significantly influenced the marine electronics industry, particularly in the context of open-source software (OSS) development. In contrast to many other industries where OSS plays a pivotal role in innovation and development, the marine sector has seen limited proliferation of OSS. The most notable industries being technology with OSS powering operating systems (Linux), programming languages (Python, Java), databases (MySQL, PostgreSQL). The financial industry is another example with the use of OSS for data analysis (R, pandas), blockchain technology (Ethereum), and infrastructure management (Kubernetes). The reason for limited proliferation of OSS in the marine sector is largely due to the stringent controls and licensing requirements associated with NMEA 2000, which pose substantial barriers to the open collaboration and community-driven development that characterize the OSS movement.
In most sectors, technology and financial sectors as discussed above, OSS has been a catalyst for rapid technological advances and widespread adoption due to its accessibility and collaborative nature. However, the closed, proprietary framework of NMEA 2000 has stymied similar progress in marine electronics. This restriction has not only slowed the pace of innovation but also limited the diversity of applications and solutions available in the market. Furthermore, the proprietary nature of NMEA 2000 significantly increases the costs associated with marine electronics. Manufacturers must pay licensing fees, invest in specialized training, and comply with strict development guidelines, all of which contribute to higher end-user prices. Additionally, this controlled environment largely limits competition to the big existing players, allowing them to dominate the market and charge exorbitant prices. This lack of competition stifles not just innovation but also keeps prices artificially high, placing advanced marine technology out of reach for many. In our view, this proprietary lock-down is a key factor behind the marine industry's lag in harnessing the full potential of modern software technologies. By maintaining tight control over the development ecosystem, the industry may be preserving traditional business models, but at the cost of stifling the creative and technical dynamism that open-source protocols could bring, and dramatically escalating costs, thus restricting access to advanced marine technology.
Furthermore, it's important to recognize the role of standards like RS-232 and RS-422 for NMEA 0183, and J1939 for NMEA 2000. These standards open up opportunities for boaters to use equipment that complies without the need to purchase expensive NMEA certified gear. This is particularly beneficial for younger boaters and those looking to upgrade their systems affordably, fostering evolution in system capabilities and safety.
The Trident North team is breaking the marine barrier with our current system setup. Our vessel currently operates a wifi system with NMEA 2000 and NMEA0183 equipment acting as “talkers'' within our system.. This allows our vessel to install state of the art equipment proven in other industries at a fraction of the cost of our competitors. Lookout for a future blog discussing the installation of a wifi system on your sailing vessel!
Understanding the differences between NMEA 0183 and NMEA 2000 is vital for boaters to strike a balance between affordability, safety, and an enjoyable sailing experience but what good is it if you don’t know how to identify the system you have? This blog wouldn’t be complete if we didn’t assist you in identifying which protocol you have on your boat to start commanding your sailing journey. Trident North's mission is to act as your sailing assistant and help you enhance your sailing experience.
Identifying NMEA 0183:
Physical Connections: Look for serial data cables with wires labeled "NMEA IN" and "NMEA OUT" connecting various onboard devices. These cables often have RS-232 or RS-422 connectors as shown in figure 1 below.
Device Labels: Check the labels or manuals of your onboard electronics. Devices compatible with NMEA 0183 typically mention this protocol in their specifications as shown in figure 1 below.
Figure 1: NMEA 1083 device label (1)
Single Talker-Multiple Listeners Setup: NMEA 0183 devices usually operate in a single talker-multiple listeners configuration, where one device (e.g., GPS) sends data to multiple receiving devices (e.g., chartplotter, VHF radio) illustrated in figure 3.
Identifying NMEA 2000:
Physical Connections: Look for a backbone cable (usually a thicker cable with multiple connectors as seen in figure 2 below) running through your boat's system. NMEA 2000 networks use a backbone-and-drop topology, where devices are connected via T-connectors to the backbone cable as shown in figure 2.
Figure 2: NMEA 2000 Backbone framework (2)
NMEA 2000 Labels and Logos: Check for labels, logos, or certifications on your electronic devices indicating NMEA 2000 compatibility. Look for terms like "NMEA 2000 certified," "NMEA 2000 network," or the NMEA 2000 logo.
Device Configuration: NMEA 2000 devices often require configuration or setup through a network interface, such as assigning device addresses or configuring data parameters. Check the device manuals for information on NMEA 2000 setup procedures.
Figure 3: NMEA 1083 vs. NMEA 2000 setup breakdown (3)
Conclusion: Determining Your Boat's Protocol
To determine whether your boat uses NMEA 0183 or NMEA 2000, follow these steps:
Physically inspect the connections and cables on your boat, looking for clues like serial data cables for NMEA 0183 or backbone cables for NMEA 2000.
By understanding and identifying the communication protocol used on your boat, you can ensure compatibility, make informed decisions about system upgrades or additions, and troubleshoot any communication issues effectively. Stay connected and sail with confidence, knowing your boat's communication protocols are in sync with modern marine technology standards.
Footnotes