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Question about JMRI

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Question about JMRI
Posted by Kelly523 on Saturday, April 14, 2018 6:33 PM

Can JMRI pull out the infomation about a decoder if you no nothing about it. If not and you see nothing marked on the the decoder is there any other way.

Thanks

George

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Posted by santafe5000 on Saturday, April 14, 2018 7:06 PM

Using JMRI DecoderPro hooked up to a programming track, via a programming module of your choice, can read the decoder and tell you the maker and type it is and what the current CV setting's are.

Open DecoderPro, click on NEW, then hit the button for "Read".

James in TexasCowboy

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Posted by rrinker on Saturday, April 14, 2018 7:27 PM

 JMRI will tell you the manufacturer, and maybe give  version number, but it can;t tell specific models when there are a whole range of models that use the same firmware. 

 It would be very rare there is nothing at all on the shrink wrap of the decoder, all the major manufactures put something on there. If it doesn;t have shrink wrap, a careful inspection of the board with a magnifier may show some identifying marks. Also, most manufacturers use different color shrink wrap, so you may be able to tell just based on that. Post a picture, someone can probably tell just by looking.

                                  --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by wjstix on Tuesday, April 17, 2018 11:42 AM

Decoder Pro can read the decoder type - it's reading a CV where the manufacturer puts in a number to identify the company and decoder - but it doesn't always work. When I create a Decoder Pro file for a new locomotive / decoder installation, I usually select the "read" option first to see if it picks it up OK. It usually works, but sometimes not. Oddly enough, in those failed attempts, once I enter the decoder type and hit "read all CVs" it picks them up and allows me to change them with no problems. I don't know if some companies don't fill in that particular identity CV, or some use their own system that Decoder Pro doesn't recognize, or what.

Stix
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Posted by Stevert on Tuesday, April 17, 2018 4:05 PM

wjstix

Decoder Pro can read the decoder type - it's reading a CV where the manufacturer puts in a number to identify the company and decoder - but it doesn't always work.

As Randy mentioned, JMRI tries to identify most** decoders by reading their manufacturer ID and firmware revision number.  Both of those are read-only CV's, and the manufacturer ID is assigned by the NMRA.

If JMRI can't read those values, it can't identify the decoder.  Even if it can, it may only be able to narrow it down to a family of decoders that use the same firmware revision(s). 

And that assumes someone has written a JMRI decoder definition to cover that manufacturer ID/firmware revision number.

So no, it's not a perfect system, but it's the best JMRI is able to do within the framework of the NMRA decoder specs.

**Some decoder manufacturers (I think ESU is one) put additional identifying info into other CV's.  If a decoder has such info, and someone has written a decoder definition for it, JMRI may be able to narrow it down that much more.

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Posted by maxman on Tuesday, April 17, 2018 7:11 PM

Assuming that yout command station can read CVs, would it not be easier to let the command station do it by reading CV8?

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Posted by Stevert on Wednesday, April 18, 2018 6:58 AM

maxman

Assuming that yout command station can read CVs, would it not be easier to let the command station do it by reading CV8?

 

 
That's what JMRI does.  It tells your command station or other programming device to read CV's 7 and 8, and then uses those values to select a decoder (or a decoder family, as I mentioned in a previous post.)
 
So yeah, if you think it's easier to use your throttle to read those CV's so you can manually look up that manufacturer ID and version number, instead of just clicking on "Ident", then go for it. 
 
Edit: Fixed typo
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Posted by maxman on Wednesday, April 18, 2018 6:22 PM

Stevert
That's what JMRI does. It tells your command station or other programming device to read CV's 7 and 8, and then uses those values to select a decoder (or a decoder family, as I mentioned in a previous post.) So yeah, if you think it's easier to use your throttle to read those CV's so you can manually look up that manufacturer ID and version number, instead of just clicking on "Ident", then go for it.

Sorry, my interpretation was that he did not have JMRI and was wondering if JMRI would do what he wanted.  Some of us don't have a computer in the train room.

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Posted by rrinker on Thursday, April 19, 2018 7:00 AM

Yes, you can do the same thing with a throttle, but you'll still need a computer, or at least a printout of the NMRA manufacturer IDs. ANd then a copy of every manufacturer's version numbers. A lot of the version info isn't even readily available, the only thing guaranteed is the NMRA manufactuer ID in CV8, not all manufacturers publish what they put in CV7.

                                 --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by willy6 on Thursday, April 19, 2018 3:11 PM

I know JMRI did not reconize my 2 Walthers Mainline sound locomotives. One loco was determined to be an unknown Soundtraxx version and none of those versions worked meaning the "F" functions were out lunch...F1 was the horn and F3 or F7 was the bell and the lights flickered. I programmed them both with Bachmann data and worked fine.

Being old is when you didn't loose it, it's that you just can't remember where you put it.
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Posted by Stevert on Thursday, April 19, 2018 3:41 PM

willy6

I know JMRI did not reconize my 2 Walthers Mainline sound locomotives. One loco was determined to be an unknown Soundtraxx version and none of those versions worked meaning the "F" functions were out lunch...F1 was the horn and F3 or F7 was the bell and the lights flickered. I programmed them both with Bachmann data and worked fine.

 

 
Yup, someone has to get hold of the locos, or at the very least the decoder doc for them, and write the definition to be included in JMRI.
 
Remember that JMRI is written and maintained by volunteers giving up their hobby time, and has very little manufacturer support.
 
That said, the Walthers Mainline OEM decoder definitions were added in JMRI 4.11.5, which was released just this past Sunday.
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Posted by willy6 on Friday, April 20, 2018 6:54 PM

Thanks Stevert, I'll download this weekend and see what happens.

Being old is when you didn't loose it, it's that you just can't remember where you put it.
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  • From: Ridgeville,South Carolina
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Posted by willy6 on Sunday, April 22, 2018 9:07 AM

I downloaded the new version and it has the Walthers Mainline data, Thank you.

Being old is when you didn't loose it, it's that you just can't remember where you put it.

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