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I thought CV functions were NMRA standardized...apparently not.

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Posted by mlehman on Saturday, June 29, 2013 12:34 PM

I've not made the leap to Decoder Pro quite yet, but some of my colleagues locally have, as well as many of my online narrowgauge buddies. Decoder Pro is one component of the JMRI open source model RR software complex, but you can use it without implementing JMRI to control the layout.

You install Decoder Pro on a laptop or other handy computer and use it as an automated programming track control. It stores the configuration you download to each decoder and allows easy, rather, than tedious, control of settings in the decoder. When you need the info later, you just call up that loco's file and it's all there, ready to program it again or adjust as needed.

Mike Lehman

Urbana, IL

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Posted by Over50 on Saturday, June 29, 2013 11:47 AM

chessiecat

 I have gotten into the habit of marking on the booklet that comes with most engines what engine it came with and stapleing the receipt to it. That is the only way I can keep track of the different cv's and different controlls.  Jim 

As I've learned also since I made the switch to DCC. I like the flexibility of DCC vs. DC (the sounds adding to the fun, engine direction and reverse loops w/o track polarity concerns, etc.,) but as I'm finding/found out there's a heck of learning curve contrary to the promotional hype of "just connect power to the track and away you go". And DC was a lot more forgiving with respect to wheels momentarily shorting at times passing through an insulated frog....along with general wheel/track cleanliness.....and powering a DC layout is a heck of lot cheaper.... 

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Posted by chessiecat on Saturday, June 29, 2013 8:28 AM

I just purchased the BLI NW2 also and had no problem programing it. I have gotten into the habit of marking on the booklet that comes with most engines what engine it came with and stapleing the receipt to it. That is the only way I can keep track of the different cv's and different controlls. I keep them in a file box, now if I can just remember were I put that?  Jim 

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Posted by Texas Zepher on Friday, June 28, 2013 11:30 PM

Also as far as I know NMRA has not talked about or even thought about standardizing sound controls.  

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Posted by betamax on Friday, June 28, 2013 4:28 AM

They are standardized, to a point.

Many of the advanced features are not included. If every time a manufacturer or programmer wanted to implement a new feature they had to submit this to the NMRA DCC Committee, it would take forever.  So you would have to wait before a new crop of advanced decoders appears.

Standards take time to revise.  Things have to considered, research done, and concensus reached within the committee. Takes time.

By setting a base standard and allowing freedom for new features, we all benefit. 

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Posted by mfm37 on Thursday, June 27, 2013 9:43 PM

There are only three CV's that any NMRA compliant decoder must have. CV1 , CV7, and CV8. CV29 is also mandatory but only if if any of the  non-mandatory Cv's are implemented.. More CV's up to 111 are NMRA standard but manufacturer's option. Those are standardized for what they must do. In other words if they are used, they must be for a particular NMRA defined purpose. Other CV's are defined by the NMRA as Manufacturer's option. Those can be anything the manufacturer wants to use them for.

Here's a link to the NMRA chart of Cv's.

http://www.nmra.org/standards/DCC/standards_rps/RP-9.2.2%202007%20July.pdf

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Posted by Over50 on Thursday, June 27, 2013 6:56 PM

cacole

You will have to download the Paragon2 technical reference manual from BLI to know which CV values they used for that decoder.

Find the manual you need from this list and download it.  It seems that no manufacturers or importers provide any documentation, but leave it up to the consumer to download and print your own support documents now.

http://www.broadway-limited.com/supportdocumentation.aspx

Actually that's not the case with the Paragon2 NW2 I just got. Included in the box was a glossy 24 page manual that included BLI's CV listing and description for each, the default state/factory setting of each, a "F" function list with description for each (and how to add to), the decoder reset CV= info....which if all else fails the required actions for the physical reset button on the decoder, a "Easy DCC Consist" setup (CV's)...with pictorial. Like I said, I'm really impressed with the out-of-box experience with my first BLI diesel purchase.

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Posted by mlehman on Thursday, June 27, 2013 4:40 PM

Just wait until you get your hands on a QSI. That'll send you back to the books for awhile, as it's fairly complex and has the least amount of overlap with other mfgs CV schemes (in my limited experience anyway). Let's put it this way, after much studying, I sort of have control over basic stuff, but it's like algebra at this age -- makes my head hurt.Dead

Mike Lehman

Urbana, IL

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Posted by cacole on Thursday, June 27, 2013 3:42 PM

When the NMRA Working Group established their DCC Standards and Recommended Practices only the first 128 or so CVs were "standardized", with anything higher than that left up to the manufacturers.  Sound was not even dreamed of back then, so no two sound decoders use the same CVs for sound control.

You will have to download the Paragon2 technical reference manual from BLI to know which CV values they used for that decoder.

Find the manual you need from this list and download it.  It seems that no manufacturers or importers provide any documentation, but leave it up to the consumer to download and print your own support documents now.

http://www.broadway-limited.com/supportdocumentation.aspx

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Posted by Over50 on Thursday, June 27, 2013 3:30 PM

Appreciate the replies guys. Another thing learned with my switch to DCC.

Just to mention BLI's packaging is top notch IMO....glossy multi-page manual with their CV listing, consist programming, etc. vs. having to go online to read or download the info, multi layers of foam cushioning with their package design all topped off by totally sealing the box in cellophane. First time experience with BLI is impressive all around.

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Posted by Rastafarr on Thursday, June 27, 2013 12:33 PM

CERTAIN CVs are standardized (CV29 for instance, and a few others). Every manufacturer fiddles around with the non-standardized ones to varying degrees. 

I don't have any BLI units myself -- others here are intimately familiar with them -- but check out their faq below; it may lead you to better answers than I can provide.

http://www.broadway-limited.com/faq.aspx

Don't worry. You'll get it sorted in no time!

Stu

Streamlined steam, oh, what a dream!!

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Posted by CSX Robert on Thursday, June 27, 2013 12:30 PM

Some are, some aren't.  There was no way to anticipate all the possible functions for CV's when the standards were written(it still isn't).  To know what is standardized, look at the NMRA spec(http://www.nmra.org/standards/sandrp/pdf/S-9.2.2_2012_10.pdf).

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I thought CV functions were NMRA standardized...apparently not.
Posted by Over50 on Thursday, June 27, 2013 12:04 PM

Just got a Broadway Limited EMD NW2 switcher with Paragon2 sound decoder yesterday and found out the CV to adjust the overall sound volume is not the same CV number for a Soundtraxx decoder. Same for the bell volume among others comparing the included BLI CV listing and Soundtraxx' CV listing.

I thought the CV table was NMRA standardized..??

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