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Letter to NMEA - Unresponded discussion with NMEA Options · View
marinettejoe
Posted: Sunday, March 16, 2008 9:01:21 AM

Rank: Administration
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Joined: 12/3/2007
Posts: 239
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Location: Stafford
All,

This sent a couple of weeks ago to NMEA in a prepublished courtesy note, allowing a reasonable response. I am not a journalist. These are my opinions, and recollection of the phone discussion with Steve Spitzer.

I, MarinetteJoe had a long discussion with Steve Spitzer of the National Marine Electronics Association. While Steve, speaking for NMEA, was more understanding of a hobbyist viewpoint than the David Hayden, he reflected on the considerable cost and investment that the NMEA members had. At that time, David was surprised that some one would be a hobbyist of this type, not unsympathetic or hostile.

First, Steve and I discussed the need, cost and availability of the NMEA 2000 standard as well as which standard items are necessary to the hobbyist. We discussed that issues "in no case, were hobbyists considered in the standard", despite the knowledge that most boats are worked on by owners. I assured him, I am respectful of the intellectual property and laws. Our discussion was friendly and professional.

I stated that my intent is to develop as a hobbyist some of my own equipment and help others do the same. I am trying to remain cognizant and sympathetic to the NMEA organization. Also, I am a paying member associate of NMEA.

We discussed, what to buy in standards:

Effectively, the primer is designed for the installer. I would recommend the primer and the database for an installer, like Russ. The database is a far more living document and the purchaser should understand that it is subject to change. NMEA split out the documents to make those more useful documents nearer the cost for a developer or installer.

Prices for the moment are here at https://www.nmea.org/secure/purchase.cgi?T=P

A embedded systems hobbyist is recommended by NMEA to purchase the main document, and the database and the application layer appendix A. NMEA cuts it's members a serious break on the ISO standard, but as I did look around online. IHS and SAE have these cheaper and the ISOBUS test procedures are online. $450+350+495. Application notes can shorten the development process and usually contain significant data on the reference design.

Do I have to buy the standards ? No. And can I develop an interoperative solution that is non conforming and does not violate the license? Yes, Simply by using J1939, Or developing a user entered values scheme. (Everything but the magic codes.)

By the way, a parameterized device provides a sample packet which the user defines to a specific meaning. Since the device stores no packet preconception, it contains no proprietary standard information (Ethernet people would call this a packer sniffer approach). It's not a safe strategy for talkers to have a control system that's parameterized, but fine for listeners. It's analogous to the common approach with learning type TV remotes, also. As an embedded systems engineer-programmer I could either have trained the device on the protocol or parameterized the packet structure (solution (only safe in a listen mode) without buying these products, and as of yet haven't purchased them. Mostly, because the boat is still in the shop for the re-engine.

Costs:

Standards... It's not coming down, any time soon. NMEA is also concerned that small one man businesses would be really upset if the cost lowered based on the prices they already paid. I am not sure I agree with that assessment as a revision might require a new purchase. The updates incur a recurring cost could be high (e.g. if packetization proposed by Maretron in added) adds a rewrite to the standard. A person using a product gateway might be able to do with the database for an application on a PC. Compared to SAE J1939 (595) it's 4 times as expensive. (J1939 which has a free stack source by Microchip and a second by Drewtech available.)

(I, Joseph recommend that a hobbyist using one of these devices by a properly isolated unit. Not just the CAN, but ground also. - Galvanically Isolated and no ground loops.)

Availability : Right now the NMEA is the only source for the documents. There are no plans to place them in a library or retail them through SAE or IHS.

We discussed NMEA works hand in hand with the International Standards Organization (ISO), National Institute for Automotive Service Excellence (ASE), USCG and the Society of Automotive Engineers (SAE) and to a lesser extent Kansas and Oklahoma Universities. SUN and some other manufacturers played a role in the standard. I hope to get more information from the USCG FOIA request I have submitted (list and access to all R&D items that were paid from public funds).

On writing and releasing software source code.

Currently NMEA states that a public release of my C or java source code cannot be made with the hobby project without violating NMEA licenses if I code in the PGNs values. I am not sure what that means in relationship to the license. Additionally interoperability on the bus is separate from the standard. This concept was not discussed in detail. I also touched on lightly the lack on content on the NMEA site and the web site forum. The internal should be an active site with a rich forum.

I do feel, though not discussed that this license goes against the hobbyist and open source movements. More than one manufacturer depends upon GNU G++, Eclipse, or Linux open source.

I also stated I was cognizant of the cost of standards maintenance and the burden it places on an organization. Finally I mentioned that I had approached a manufacturer or two on a hobbyist module that we could incorporate in our solutions. (Like e-blocks.)

We did not go into bus limitations or deep technical issues. I did mention, I had installed 2 FWMurphy Helmviews and new Crusaders as part of a general upgrade. I also discussed I had considerable systems engineering experience (more in RT Ethernet) and considered an IPV6 on Sixnet(TM) Ring MilSpec Ethernet. It would have been cheaper.

I had discussed with Steve on an earlier occasion that I would like to hold a marine electronics design contest for hobbyists.

Steve Spitzer is to review this letter (hopefully for a week) and have a chance to respond.

Conclusion:

NMEA has been unaware that hobbyists exist who are interested in development of their own equipment. That is changing. Steve and David have remained professional and appropriate, and I intend to do the same. Nevertheless, I feel the interests of boaters, the market and NMEA is best served by a more affordable and open standard. Legally, I think they are unwise to limit C code release. As the SAE and other organizations that restricted hobbyists or open source code (I mean computer C code or java cource, not copying the database) have not done well (e.g. Drewtech vs SAE on J1939 and Microchip's PIC J1939 stack source).
Added ....
A recent internal NMEA survey turned up the following...

NMEA Board: Establishes a cohesive identity to its membership and the boating public
Excellent or Good: 29.6%
Average: 34.5%
Below Average: 28.6%
Don’t Know: 7.3%

And the primary challenge in ME - Difficulty in finding qualified technical personnel ....

Many hobbyists offer the opportunity to develop the electronics maturity of the field (Apple II and Personal Computers started as hobbyist capabilities. Additionally small businesses can leverage hobbyists to develop and market products.

Respectfully seeking advisement and comments

MarinettteJoe

www.marinetteboat.com/forum
NMEA member.


Unzinced ships sink at slips.
Sponsor
Posted: Sunday, March 16, 2008 9:01:21 AM
Please Register : New members may not post until approved. An email is sent after approval. We do this to reduce those who use these forums for spamming. This forum is for Marinette Owners and other aluminum boat boaters who wish to share boating information. Aluminum Roamer owners are also welcome. (Do not post content you do not have the right to post and mass (robots) posters are unwelcome. We also have a marine electronics page and lots of Chrysler Engine info. State by what permission, you copy content and accredit properly.) The site is now fixed with some more Chrysler information. I will try to post more information soon. We have space for pictures on the new location. Use shinkpic to autochange size http://www.onthegosoft.com/sp_download.htm

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fpmurphy
Posted: Monday, March 17, 2008 2:50:42 AM
Rank: Newbie
Groups: Member

Joined: 1/30/2008
Posts: 0
Points: 96
Location: Florida
There is nothing to stop you developing your own N2K stack in C, Java, etc. except your own time and energy. 90% of the PGN information is freely available as in published by N2K equipment suppliers in their equipment user guides. Think Maretron, Raymarine, Furuno, etc.
marinettejoe
Posted: Monday, March 17, 2008 6:15:34 PM

Rank: Administration
Groups: Administration , Member, Other Mods

Joined: 12/3/2007
Posts: 239
Points: 200
Location: Stafford
fpmurphy wrote:
There is nothing to stop you developing your own N2K stack in C, Java, etc. except your own time and energy. 90% of the PGN information is freely available as in published by N2K equipment suppliers in their equipment user guides. Think Maretron, Raymarine, Furuno, etc.


Thanks fp.... It's appreciated. That's where I am at now, except I won't need a full stack. . I purchased a the Maretron Fuel Sender and will be working with that and will release me listener only fuel reader. I was hoping digikey sold NMEA approved circular connectors (marine waterproof, not just waterproof). I think LTW will be the sourcer for plugs on the device.
Thanks


Unzinced ships sink at slips.
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