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Long address less than 128

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Long address less than 128
Posted by grinnell on Tuesday, July 16, 2013 10:29 PM

On my NCE system I have long addresses less than 128. How do I run those locos on a layout that uses Digitrax?  Do I have to change them to a short address? or is their something else I can do (the digitrax manual doesn't seem to have the concept of long addresses less than 128)?

 

Grinnell

 

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Posted by KemacPrr on Tuesday, July 16, 2013 10:37 PM

You can't. Digitrax will not recognize the 4 digit address under 128 like NCE will. I'm guessing you have used a 0 as the lead digit. Such as engine 105 uses address 0105. You'll have to change it to a 1-127 2-3 digit address for Digitrax. ----------------- Ken

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Posted by retsignalmtr on Wednesday, July 17, 2013 5:26 AM

On a Digitrax system any address up to 127 is considered a 2 digit address. So address 105 can be entered and run as 105. Any address higher than 127 must be used with the leading 0. So address would be 0128. 

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Posted by rrinker on Wednesday, July 17, 2013 6:27 AM

 Probably the biggest failure of the NMRA standard - on Digitrax, 1-127 is ALWAYS a short address, 128+ is a long address. On Lenz, 1-99 is always a short address, 100+ is always a long address. On NCE, 10127 can be a long or short address, 127+ is always a long address. So there are ranges od addresses that will work on one system but not another. And you can have a loco address 5 and another 005 on NCE and they are two different addresses - the former a short address, the latter a long address.

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Posted by CSX Robert on Wednesday, July 17, 2013 7:02 AM

retsignalmtr

...Any address higher than 127 must be used with the leading 0. So address would be 0128. 

No, the leading zero is not required.  Since addresses above 127 can only be extended addresses, no leading zero is ever required on addresses above 127.  The leading zero is only required on NCE on addresses below 128 to distinguish between an extended address and primary address, and never required on Digitrax.

 

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Posted by CSX Robert on Wednesday, July 17, 2013 7:28 AM

rrinker

 Probably the biggest failure of the NMRA standard...

I don't find it a failure of the standard, but a failure of the manufactureres to clearly define and implement the standard.  I feel the whole idea of introducing the "2-digit", and "4-digit", and "short" and "long" address phrases only served to confuse matters further('123' is a 2-digit address?, '456' is a 4-digit address, '3' can be either?).  None of those terms are ever used in the NMRA standards, they are primary and extended addresses.  I belive that If the manufacturers were clear from the beginning that there are two distinct and separate addresses - the primary address, which can have any value from 1-127, and the extended address, which can have any value from 0 to 10239 - and then clearly stated what range of each address they supported, it would have saved a lot of confusion.

 

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Posted by Phoebe Vet on Wednesday, July 17, 2013 8:09 AM

It is because you are thinking in Decimal and the command station it thinking in Binary so the code is written in Hexidecimal.

Dave

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Posted by CSX Robert on Wednesday, July 17, 2013 9:48 AM

Phoebe Vet

It is because you are thinking in Decimal and the command station it thinking in Binary so the code is written in Hexidecimal.

Yes, I understand that 100-127 can be represented in two digits in hexadecimal.  I was not asking the questions I posed above, but simply listing them as questions that are often asked in the confusion caused by the whole idea of 2-digit and 4-digit addresses.  Here's another one: 128-255 could also be represented in two digits, so why aren't they 2-digit addresses? 

Digitrax uses 1-127 as 2-digit only because that is the range of primary addresses and they can be represented by 2-digits in hexadecimal.  Lenz limits 2-digit addresses to 1-99 because we generally do not deal with hexadecimal when dealing with the decoder.  Two different manufactureres usiing "2-digit" and "4-digit" in different ways.

 It would help if they had explained "this is the range and this is what we use", instead of "these are 2-digit addresses and these are 4-digit addresses", but even using the terms 2-digit and 4-digit adds to the confusion. For example, I've seen people think that you have to enter addresses from 100-999 with a leading zero to make them  "4-digit" addresses.  I've also seen people think that you have to enter addresses 1-9 with a leading zero to make them "2-digit" addresses.  If you do all of your programming and running on a Digitrax or Lenz system entering a leading zero when not required won't cause a problem.  Same thing with NCE, for the most part - I have heard of people trying to run an engine on the default  "2-digit" address of '3' by entering '03', which NCE interprets as the "4-digit address" '3' - but when you start using more than one system it can cause problems.

 

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Posted by grinnell on Wednesday, July 17, 2013 10:05 AM

I'm still confused. For my engine 45, I enter 045 on my NCE system (a long address). On a Digitrax layout, if i set the throttle to 0045, will it run?

Grinnell

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Posted by maxman on Wednesday, July 17, 2013 11:11 AM

grinnell

I'm still confused. For my engine 45, I enter 045 on my NCE system (a long address). On a Digitrax layout, if i set the throttle to 0045, will it run?

Grinnell

I think the question is where does Digitrax look to determine the loco address.
 
If it looks for short addresses (127 and lower) in CV1, and extended addresses >127 in CVs 17 and 18, then you will have to change CV1 in your loco to 45.  This is because NCE recognizes your 045 as a long address and calculates values in CV 17 and 18 to give that address.  If Digitrax ignores values in CV 17 and 18 for addresses <128, it will not see your loco.
 
Digitrax experts need to answer that question. 
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Posted by retsignalmtr on Wednesday, July 17, 2013 2:05 PM

Since Digitrax has a four digit display on its display, entering a three digit address will automatically leave the first digit as 0. On the UT series throttles the first number of the address would have to be entered as 0

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Posted by maxman on Wednesday, July 17, 2013 2:10 PM

What the display shows is not relevant to the question.  Decoder CV1 is for short addresses, and CVs 17 and 18 are for extended addresses.  When you ask the Digitrax command station to look for address 45, does it look at CV 1, or does it look at CVs 17 and 18?

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Posted by rrinker on Wednesday, July 17, 2013 5:35 PM

 It's a failure of the standard because it allows manufacturers to do three different and incompatible things and yet still meet the standard. Every one of those systems meets the standards, yet they allow for locos that can run on one or two of the systems but not all three. That's a failure of the standard to establish secific guidance and not a failure of the manufacturers to be consistent - they ARE consistent - consistently following the allowable standard!

 Mainly I think to accomodate Lenz, who used a pair of LED displays for address, which means they couldn;t go over 99 on their original system, even though the address ued 7 bits, which really allows up to 127. Digitrax took advantage of that from the beginning. The extended standard then added CV17 and CV18 for long addresses, I guess Lenz chose the 99/100 cutoff to remain compatible with their older short address  only systems, Digitrax already was going up to 127 for short addresses, and NCE I guess did what they did so they could effectly reserve the 1-127 address range for consists, since to this day, consists can only use 1-127 (for CV19 consisting).

               --Randy

 


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Posted by retsignalmtr on Wednesday, July 17, 2013 7:47 PM

If I enter an address of 45 on a Digitrax throttle I don't care what CV it looks at. It runs the loco with the address of 45. If I go to program a loco with a 4 digit address I don't care how many CV's it uses. It does it automatically, every time.

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Posted by Lake on Wednesday, July 17, 2013 8:33 PM

I have always just added a '0' to the end of a three numbered engine and then program it as a four digit address.

506 then becomes 5060, 422 becomes 4220. Then no problem running on other systems. So far this has worked fine. If some one brings an engine programed on an other system with three digits that will not run for some reason then a quick reprogramming adding a '0' works. It then ran on their system as a four digit number.

Ken G Price   My N-Scale Layout

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Posted by maxman on Wednesday, July 17, 2013 9:07 PM

retsignalmtr

If I enter an address of 45 on a Digitrax throttle I don't care what CV it looks at. It runs the loco with the address of 45. If I go to program a loco with a 4 digit address I don't care how many CV's it uses. It does it automatically, every time.

I guess that nobody is looking at the question.  The OP has a loco, programmed on an NCE system, with an address of 045.  With NCE, that is a long address and CVs 17 and 18 get calculated such that the loco will run with a long address of 045.
 
So, what the OP wants to know is if he takes that same loco to a Digitrax operated railroad  will that system look at CVs 17 and 18, ignore the leading zero, and operate the loco on address 45?  Or will he have to reprogram the loco to address 45 with the Digitrax controller?
 
So while a Digitrax user may not care which CV gets looked at or what gets done automatically, it is important to the OP.  If Digitrax does not recognize long addresses (CVs 17 and 18) below 128 and looks at CV 1 to get that answer, then the OP will have to re-program his loco from NCE long address 045 to short address 45.
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Posted by CSX Robert on Wednesday, July 17, 2013 9:16 PM

maxman

...Decoder CV1 is for short addresses, and CVs 17 and 18 are for extended addresses.  When you ask the Digitrax command station to look for address 45, does it look at CV 1, or does it look at CVs 17 and 18?

Niether.  When you select address 45 on Digitrax, it will send commands to the primary address 45.  The command station does not look for the address anywhere(other than in it's own slot table to see if the locomotive is already selected and to get it's current throttle settings), it does not know if there is a locomotive with that address or not, it just sends the commands regardless.  The locomotive knows whether to use it's primary address or it's extended address according to the setting in CV29.  If the locomotive is set to use it's extended address, then it will ignore commands sent to the primary address 45, whether the extended address is 45 or not.  If the locomotive is set to use it's primary address, and it's primary address is 45, then the locomotive will respond to commands sent to the primary address 45.

 

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Posted by maxman on Wednesday, July 17, 2013 9:26 PM

CSX Robert
Niether.  When you select address 45 on Digitrax, it will send commands to the primary address 45.  The command station does not look for the address anywhere(other than in it's own slot table to see if the locomotive is already selected and to get it's current throttle settings), it does not know if there is a locomotive with that address or not, it just sends the commands regardless.  The locomotive knows whether to use it's primary address or it's extended address according to the setting in CV29.  If the locomotive is set to use it's extended address, then it will ignore commands sent to the primary address 45, whether the extended address is 45 or not.  If the locomotive is set to use it's primary address, and it's primary address is 45, then the locomotive will respond to commands sent to the primary address 45.

Okay, that's a little more information.

So another question.  When programming a loco address with Digitrax, if the address wanted is 45 does the system put the appropriate value in CV1, CVs 17 and 18, or is there an option to use either using a value in CV 29?

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Posted by CSX Robert on Wednesday, July 17, 2013 9:28 PM

 

maxman

...

I guess that nobody is looking at the question.  The OP has a loco, programmed on an NCE system, with an address of 045.  With NCE, that is a long address and CVs 17 and 18 get calculated such that the loco will run with a long address of 045.

 
So, what the OP wants to know is if he takes that same loco to a Digitrax operated railroad  will that system look at CVs 17 and 18, ignore the leading zero, and operate the loco on address 45?  Or will he have to reprogram the loco to address 45 with the Digitrax controller?..

The first response answered the question, but I'll restate it to try to make it clear.  If it was programmed as 045 on the NCE system, then it will not run on the Digitrax system without being reprogrammed to an address that the Digitrax system recognizes.  If it is reprogrammed to 45 then it will run on the Digitrax system.

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Posted by rrinker on Wednesday, July 17, 2013 9:37 PM

 FIrst two posts answered the question with respect to Digitrax, I added Lenz. I think the OP's question was definitely covered, before we got to the second page.

 

             --Randy


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Posted by CSX Robert on Wednesday, July 17, 2013 9:55 PM

 

maxman

... 

So another question.  When programming a loco address with Digitrax, if the address wanted is 45 does the system put the appropriate value in CV1, CVs 17 and 18, or is there an option to use either using a value in CV 29?

When programming an address, the first thing you do is tell the system whether you are programming the "2-digit" address or the "4-digit" address.   If you tell it you are programming the 2-digit address, you can enter an address up to 127 and the command station will write that value to CV1.  When you change a decoder's primary address, the decoder is supposed to automatically clear the extended address bit in CV29, so there is no need to for the command station to change CV29.

If you tell the system you are programming the 4-digit address, the command station will calculate the correct values for CV17 and 18 and program them, then either automatically program CV29 to enable the extended address(if using a Zephyr) or ask if you want to enable 4-digit addressing and if you press "Y" it will program CV29.

Here's the funny thing - even though you can not select and run 4-digit address less than 128 on a Digitrax system, you can program one - if you tell it you are programming a 4-digit address, it will not prevent you from entering one less than 128.

 

 

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Posted by maxman on Wednesday, July 17, 2013 11:23 PM

CSX Robert
Here's the funny thing - even though you can not select and run 4-digit address less than 128 on a Digitrax system, you can program one - if you tell it you are programming a 4-digit address, it will not prevent you from entering one less than 128.

So, if I have a loco with a long address of 145 that I have programmed on my NCE system and bring it over to your house, and dial up 145 with your handset, will I be able to run the loco without additional programming?

And if I have a loco with a long address of 45 (actually 045) and a short address of some other number (say 3) that I have programmed on my NCE system and bring it over to your house, and dial up 45 with your handset it will not run because Digitrax will not run a long address less than 128.  Is that correct?  But it would run if I dialed up address 3.  Is that also correct?

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Posted by CSX Robert on Thursday, July 18, 2013 12:05 AM

 

maxman

... 

So, if I have a loco with a long address of 145 that I have programmed on my NCE system and bring it over to your house, and dial up 145 with your handset, will I be able to run the loco without additional programming?

...

Correct.

maxman

... 

And if I have a loco with a long address of 45 (actually 045) and a short address of some other number (say 3) that I have programmed on my NCE system and bring it over to your house, and dial up 45 with your handset it will not run because Digitrax will not run a long address less than 128.  Is that correct?..

Correct.

maxman

...But it would run if I dialed up address 3.  Is that also correct?

Depends.  How is CV29 set?  If it was set to the extended address(if you had been running it on the NCE system using 045, then it is set to the extended address), then no, it would not run on address 3.  You would have to program CV29 to disable the extended address for the locomotive to run on the primary address, then it would run on '3'.

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Posted by CSX Robert on Thursday, July 18, 2013 12:13 AM

rrinker

 It's a failure of the standard because it allows manufacturers to do three different and incompatible things and yet still meet the standard. Every one of those systems meets the standards, yet they allow for locos that can run on one or two of the systems but not all three. That's a failure of the standard to establish secific guidance and not a failure of the manufacturers to be consistent - they ARE consistent - consistently following the allowable standard!

...

The locos will still run all all three systems, you may have to change the address, but they will run on and are compatible with all three systems.  The only way the NMRA could ensure that  a locomotive programmed on one system would work on any other without an address change would be to require that all systems support the entire adderss range.  The NMRA felt this was not a good idea, and with good reason.

rrinker

... 

Mainly I think to accomodate Lenz, who used a pair of LED displays for address, which means they couldn;t go over 99 on their original system, even though the address ued 7 bits, which really allows up to 127. Digitrax took advantage of that from the beginning. The extended standard then added CV17 and CV18 for long addresses, I guess Lenz chose the 99/100 cutoff to remain compatible with their older short address  only systems, Digitrax already was going up to 127 for short addresses, and NCE I guess did what they did so they could effectly reserve the 1-127 address range for consists, since to this day, consists can only use 1-127 (for CV19 consisting).

               --Randy

 

 

The reason the NMRA did not require that all systems support the full address range is so that manufactureres could produce DCC systems at a lower cost to both encourage manufacturers to actually produce systems and to widen the DCC user base with affordable systems.  The first Digitrax system, the Challenger, did not go to 127, but only 15.  The throttle for the Challenger was 4 potentiometers and 8 buttons, and no intelligence.This allowed Digitrax to produce a relatively affordable system.  If the system had had to support 127 addresses, the throttle clearly would have had to have been more complicated, resulting in a more costly system.  Who, knows, if that had been the case, we might not have even have Digitrax today.  My first DCC system was an MRC Command 2000, which only supported 10 addresses.  Again, by limiting the supported addresses, they were able to produce an inexpensive system, which was the only one I could afford at the time.  The Command 2000 got me hooked on DCC.  If it had not been for it, I  still would have eventually converted to DCC, but it likely would have been many years later.

 

 

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Posted by grinnell on Thursday, July 18, 2013 12:21 AM

I'm the OP and tonite I took my loco programmed for 045 by NCE to a club that has digitrax and it would not respond when I dialed in 0045 on a digitrax throttle. So I'll have to change to a short address to run at the club or I may adopt the clever suggestion of padding my 2 digit loco numbers with trailing zeros so 45 becomes 4500, etc.

Grinnell

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Posted by richhotrain on Thursday, July 18, 2013 5:18 AM

I have been following this thread with interest, and I find it amazing that, in this day and age of standardization, this conflict occurs between NCE and Digitrax (and others as well).

I use NCE, and I am exclusively home bound with my layout, so for me this is not an issue.  But, I can see where others are inhibited by this incompatibilty between systems.

Just out of curiosity, is the OP's loco actually numbered 45?

My lowest numbered loco was 253 until I acquired a set of BLI Blueline F7s, numbered 38L, 38A, 38B, 38C.  I numbered them 381, 382, 383, 384, so there still would be no problem in this instance.  But, the problem remains for users with locos numbered 127 or lower.  Incredible!

Even the NCE system with its greater flexibility than Digitrax can be confusing.  For convenience, I long ago added the following notation to my programming notes.

Note: Consist number cannot be higher than 127.  A "Leading Zero" is necessary for long addresses below 128.  A long address between 1 and 127 will have an asterisk (*) before the loco address on the cab display.

Rich

Alton Junction

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Posted by maxman on Thursday, July 18, 2013 7:07 AM

grinnell

I'm the OP and tonite I took my loco programmed for 045 by NCE to a club that has digitrax and it would not respond when I dialed in 0045 on a digitrax throttle. So I'll have to change to a short address to run at the club or I may adopt the clever suggestion of padding my 2 digit loco numbers with trailing zeros so 45 becomes 4500, etc.

Grinnell


 
Based on CSX Robert's reply above, the easiest thing to do would be to temporarily change your loco's short address to 45 from whatever it is now (probably 3) and make the short address active.  Then I believe it should run at your club.
 
I'm not a fan of any of the adding zero or anything else to the address schemes.  While what the number really is might be obvious to you, to anyone else who tries to run the loco it is invisible and just causes confusion.
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Posted by maxman on Thursday, July 18, 2013 7:09 AM

CSX Robert
If it was set to the extended address(if you had been running it on the NCE system using 045, then it is set to the extended address), then no, it would not run on address 3.  You would have to program CV29 to disable the extended address for the locomotive to run on the primary address, then it would run on '3'.

Thank you.  That was the answer that I was trying to confirm.

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Posted by grinnell on Thursday, July 18, 2013 10:38 AM

richhotrain

Just out of curiosity, is the OP's loco actually numbered 45?

Yes, my Montana Central doesn't have many locos and 45, 56, 67 are easy with number set decals, and  Northern Pacific conveniently had a 2-8-0 number 23 assigned to Helena (Helengon in my world) in the early in 50's.

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Posted by richhotrain on Thursday, July 18, 2013 10:54 AM

grinnell

richhotrain

Just out of curiosity, is the OP's loco actually numbered 45?

Yes, my Montana Central doesn't have many locos and 45, 56, 67 are easy with number set decals, and  Northern Pacific conveniently had a 2-8-0 number 23 assigned to Helena (Helengon in my world) in the early in 50's.

Grinnell

 

ahh, I see.

Among the many solutions, one would be to simply add a 1 following the 2-digit cab number, e.g., 451,561, 671.

Rich

Alton Junction

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