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Broadway Limited E7A, runs backwards only in 128 speed step mode?

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Posted by rrinker on Tuesday, September 22, 2015 9:50 PM

 Yes, those addresses test different bit patterns in CV18. It looks like any time CV18 is 63, it's a problem. That's 0011 1111 in binary. But the problem could be the top 2 bits being 0, or the bottom 6 bits being 1. So some address where CV18 in binary is 1100 0000 would be a good test, that's 192. Also something where CV18 is 255, or 1111 1111 - does the problem only appear when the lower 6 bits are 1, or if at least 6 bits are 1's. Likewise others I didn't mention, like maybe 0111 1110 which is 126, or 1111 1100 which is 252. Not that this will solve anything, but it is an intriguing weird bug and it would be interesting to know under just what contitions it appears. And hopefully BLI will shed some light on what happens with other DCC systems, to see if it is an interaction between NCE and certain addresses or if it is strictly some strange programming in the decoder.  A little comparision between the troublesome bit patterns dn the NRMA DCC packet definitions may also yield some insight into what BLI may have done wrong. What's odd about this is that it happens in the middle of the value range for the CV - I'd more likely expect problems when the CV is at its max or min value, as a simple math mistake adding 1 or subtracting 1 would cause the value to overflow or roll over, resulting in quite unexpected operation. This being at 63 is odd - add 1 and get 64, and it's fine, subtract 1 and get 62, those values work fine.

                  --Randy


Modeling the Reading Railroad in the 1950's

 

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Posted by Anonymous on Tuesday, September 22, 2015 7:24 PM

Randy,

I gather that you reccommend trying the following addresses as well as further testing:  6015, 6080, and 6143?

Andrew

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Posted by richhotrain on Tuesday, September 22, 2015 3:51 PM

BMMECNYC

  

richhotrain
BMMECNYC

Contacted BLI, they are looking into this issue and said they will contact me with an answer. 

 

Interesting that they did not indicate any previous awareness of the issue.

Rich

 

Not really suprised, you wouldn't test functionality on all 10,000 addresses, that would be kind of expensive.  And only 38 of the addresses would cause a problem, so its a 1 in 263 chance that you would test a decoder address with an issue. 

BLI also said they would test this on their NCE system and other systems to see if the problem replicates across other DCC systems.

Assuming it is a decoder flaw, I wonder how it happened.  In other words, what did the engineer do wrong to make the loco run only in reverse on 128 speed. We will likely never know.
 
And, as Randy has suggested, it could occur with other CV18 values as well, not just 63.
 
Rich

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Posted by Anonymous on Tuesday, September 22, 2015 2:52 PM

richhotrain
 
BMMECNYC

Contacted BLI, they are looking into this issue and said they will contact me with an answer. 

 

 

 

Interesting that they did not indicate any previous awareness of the issue.

 

Rich

Not really suprised, you wouldn't test functionality on all 10,000 addresses, that would be kind of expensive.  And only 38 of the addresses would cause a problem, so its a 1 in 263 chance that you would test a decoder address with an issue. 

BLI also said they would test this on their NCE system and other systems to see if the problem replicates across other DCC systems.

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Posted by richhotrain on Tuesday, September 22, 2015 1:47 PM

BMMECNYC

Contacted BLI, they are looking into this issue and said they will contact me with an answer. 

 

Interesting that they did not indicate any previous awareness of the issue.

Rich

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Posted by Anonymous on Tuesday, September 22, 2015 1:42 PM

Contacted BLI, they are looking into this issue and said they will contact me with an answer. 

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Posted by Anonymous on Monday, September 21, 2015 9:18 PM

I was unable to contact BLI today, I had to work late.  I will attempt again tomorrow.  

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Posted by richhotrain on Monday, September 21, 2015 8:57 PM

I haven't heard back from the NCE-DCC forum.  I am hopeful that someone there can shed some light on this issue.

Rich

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Posted by rrinker on Monday, September 21, 2015 8:53 PM

Yes, yes it would. i was getting ahead of myself on bits there. Although there are at least 2 other possibilities to try as well. Or just one, depending on the outcome. 6080 to set CV18 at 192, the inverse of 63.

                --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 richhotrain on Monday, September 21, 2015 8:34 PM

rrinker

 Now - who has a Paragon 2 loco and another DCC system to try this? I don't have any - they have yet to release a Paragon 2 loco that I would want. Curious now if this is a Paragaon 2 general issue, or a Paragon 2 compatibility problem with NCE.

 Oh yes, how about an address with CV18 = 127,or 255 so 7 or 8 bits are on (compared to 63 with 6 bits on)? 6016 and 6143 would be examples.

                 --Randy

 

6016 would be 128.  6015 would be 127.

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Posted by rrinker on Monday, September 21, 2015 7:01 PM

 Now - who has a Paragon 2 loco and another DCC system to try this? I don't have any - they have yet to release a Paragon 2 loco that I would want. Curious now if this is a Paragaon 2 general issue, or a Paragon 2 compatibility problem with NCE.

 Oh yes, how about an address with CV18 = 127,or 255 so 7 or 8 bits are on (compared to 63 with 6 bits on)? 6016 and 6143 would be examples.

                 --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 richhotrain on Monday, September 21, 2015 5:26 PM

rrinker

63 is 011111111 binary so it's either a problem with the lower 7 bits all being 1, or the upper bit being 0.  

Try 5952 - that's 64 in CV18, or 10000000

And try 5695, that's just another one with CV18 = 63. 

I think we found a bug in the Paragon 2. This sounds familiar, did we already discuss something similar before, a few months or maybe a year ago? I remember some involving bit patterns.

It's CV18, the low byte (00111111).  No matter what the long address, if the value of CV18 should be 63, the loco only runs in reverse with a 128 speed setting.  I cannot explain it.  My first thought is that pressing the speed button and toggling to 128 is affecting CV29, but that can't be the case because pressing the Direction button on the ProCab to reverse would make the loco go forward.  But the loco only goes in reverse on the 128 speed button, no matter which way the Direction button is pressed.

Rich

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Posted by rrinker on Monday, September 21, 2015 1:37 PM

63 is 011111111 binary so it's either a problem with the lower 7 bits all being 1, or the upper bit being 0.  

Try 5952 - that's 64 in CV18, or 10000000

And try 5695, that's just another one with CV18 = 63. 

I think we found a bug in the Paragon 2. This sounds familiar, did we already discuss something similar before, a few months or maybe a year ago? I remember some involving bit patterns.

 

                    --Randy


Modeling the Reading Railroad in the 1950's

 

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Posted by richhotrain on Monday, September 21, 2015 9:30 AM

I have one other BLI Paragon 2.  Same problem when programmed with long address 6207.

I changed the long address to 5951, as Randy suggested.  Same problem.

So, the fault may be in the bit patterns on CV17 and/or CV18.

Rich

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Posted by Anonymous on Sunday, September 20, 2015 8:42 PM

Randy,

I did reset the system, with no change in the behavior with this locomotive.  The address works with other decoder brands.  Thank you for the suggestion on playing with the bit values to attempt to isolate which CV is causing the issue.  I believe this is a good next logical step.  Also thanks for the link to the calculator.  Also I can access digitrax now, before I couldnt even navigate to the website, however those are the CV values that Rich and I got for Long address 6207.  I will continue tomorrow after work. 

Andrew

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Posted by richhotrain on Sunday, September 20, 2015 8:28 PM

rrinker

I still say it's worthwhile to reset the system.

In an earlier reply, he said that he tried a command station reset, but it had no effect on the problem.

Rich

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Posted by rrinker on Sunday, September 20, 2015 7:32 PM

Try this calculator

http://www.2mm.org.uk/articles/cv29%20calculator.htm

Try long address 5951. That's still 63 in CV18, but a different value for CV17, so see if it's the bit patter of CV18 causing a problem. Use the windows calculator in programmer mode to get different binary values for CV17 and 18 to see if it has a problem only when certain bits are set, which would be a programming bug and there's nothing you can do except use a slightly different address.

 I still say it's worthwhile to reset the system.

              --Randy

I just tried the Digitrax toolbox and it is giving the correct values for CV17 and 18 - what are you getting?


Modeling the Reading Railroad in the 1950's

 

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Posted by Anonymous on Sunday, September 20, 2015 6:15 PM

Scratch the manual programming of the address using CVs, that didnt work either.  I cannot get to the digitrax cv calculator to confirm the proper CV values.

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Posted by Anonymous on Sunday, September 20, 2015 5:58 PM

richhotrain
Edit Note: I went through the same procedure described above with one of my Paragon E7A locomotives. Everything performed correctly when assigning the locomotive a long address of 6207, regardless of whether the speed setting was 28 or 128. So, it sure appears to be a quirk with the Paragon 2 locomotive. Hopefully, others with Paragon 2 locomotives will try this procedure to see if the problem is universal when assigning the long address of 6207.

I will also try my other two Paragon 2 locomotives (SW 7 and 4-6-2)

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Posted by Anonymous on Sunday, September 20, 2015 5:47 PM

Performed system reset.  BLI E7A paragon 2 programmed to 6207 still only runs in reverse on 128 speed step mode.  I will be contacting BLI monday to determine if there is something special about address 6207.

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Posted by richhotrain on Sunday, September 20, 2015 5:31 PM

BMMECNYC

What if I try reseting the decoder and then programming the long address using the CV values instead of the address programming mode?  Ive heard of decoders only taking the directly cv defined address before and I wonder if this might be a similar issue.

 

Sure, can't hurt.

Rich

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Posted by Anonymous on Sunday, September 20, 2015 4:53 PM

What if I try reseting the decoder and then programming the long address using the CV values instead of the address programming mode?  Ive heard of decoders only taking the directly cv defined address before and I wonder if this might be a similar issue.

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Posted by richhotrain on Sunday, September 20, 2015 4:40 PM

I guess the other question is whether there are any other long addresses besides 6207 that can be problematic on the Paragon 2 decoder.  For what its worth, the long address 6207 is programmed as follows: the high byte in CV17 is a value of 216, and the low byte in CV18 is 63.  When I looked at CV17 and CV18 on the programming track for long address 6207, those CV values were present.  I mention this because I do wonder if there is some peculiarity about either of these CV values.

Rich

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Posted by richhotrain on Sunday, September 20, 2015 4:25 PM

I started a thread on the NCE DCC forum over on Yahoo Groups. 

Let's see what the boys over there have to say.

Rich

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Posted by richhotrain on Sunday, September 20, 2015 4:22 PM

Here are the steps to reset the NCE PH-Pro command station to factory default, but the problem is that a reset will clear all consists, macros, and system setup parameters, but this would be a last gasp action in my view.

Rich

press prog/esc  5 times

press enter  16 times 

display will say : reset system?

press 6 for Yes

press 1 to confirm

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Posted by Anonymous on Sunday, September 20, 2015 4:14 PM

So even though other manufacturers decoders work on that one address, it is a problem with the system?  And 2 different systems are having the exact same problem with the same decoder brand.

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Posted by rrinker on Sunday, September 20, 2015 3:58 PM

But your paragon 2 loco works on any address EXCEPT that one specific one. I still says it's a system problem. Last time someone had that sort of an issue, thery did all the same stuff, sent the loco back for repairs, still had the same problem. System reset solved it.

 Is it that difficult a task with NCE? When things go wonky the first thing I do it reset the decoder. If that fails, reset the command station as the second thing to try. We are dealing with computers here and their brains can get scrambled in some very odd ways. Both NCE and Digitrax are still using the same microcontrollers they were 15+ years ago even though there are newer ones with more memory that also run 10x as fast, and cost the same. There's just not enough money in the system sales to justify the R&D time to modify the hardware and write all new code that, with more room and speed to work with, might be able to implement more error checking and cleanup to prevent some of these random issues.

                   --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 richhotrain on Sunday, September 20, 2015 3:53 PM

BMMECNYC

 

 
davidmbedard
Can you reset your DCC system? Sounds like you have that address mu'd or something. ....or its selected on another throttle?

 

 

David,

That thought had occured to me and I killed consist 6207 to be sure.  It was a few months ago but I have   deleted all E7 consists with no result (have 2 other E7s and they are the only locomotives I would have entered this one in a consist with.  

As for throttles,  I honestly dont know if that is the case or not but i will check.  The E7 in question has only been operated from my pro-cab, and I only have one pro-cab.  The rest are cab 05.

 

edit:  also I might add that the original decoder was not tested on any address other than 6207.  All testing since July posts has been on new decoder from BLI,  because I was operating on te assumption that the original decoder was faulty.  

 

Let me add a thought or two.

First, when I tested my Paragon 2 steam loco on my NCE PH-Pro, I tested it using the long address 6207 and experienced the same problem as the OP.  I have never put that loco in a consist, or perhaps the better term for a steam loco is that I have mu'd it.  However, I still checked CV19 to be sure, and the value was zero.

Second, while I do have two ProCabs, I have never used long address 6207 on any of my locos, so there is no chance that long address 6207 was present on another throttle.

Third, my NCE PH-Pro does accept the long address 6207 on non-Paragon 2 decoders without any performance problems.  

So, it is my preliminary conclusion that the NCE command station/throttle is not at fault.

I just had another thought.  I will post this issue on the NCE-DCC forum on Yahoo Groups.

Rich

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Posted by Anonymous on Sunday, September 20, 2015 3:15 PM

davidmbedard
Can you reset your DCC system? Sounds like you have that address mu'd or something. ....or its selected on another throttle?

David,

That thought had occured to me and I killed consist 6207 to be sure.  It was a few months ago but I have   deleted all E7 consists with no result (have 2 other E7s and they are the only locomotives I would have entered this one in a consist with.  

As for throttles,  I honestly dont know if that is the case or not but i will check.  The E7 in question has only been operated from my pro-cab, and I only have one pro-cab.  The rest are cab 05.

 

edit:  also I might add that the original decoder was not tested on any address other than 6207.  All testing since July posts has been on new decoder from BLI,  because I was operating on te assumption that the original decoder was faulty.  

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Posted by Anonymous on Sunday, September 20, 2015 3:04 PM

rrinker

 Your issue now is in the system itself, since another loco on the desired long address ALSO does not operate properly, but the suspect loco works fine on a short address or different long address. Somehow the internal state for that long address have become scrambled in the command station. Check the manual, I know how to reset a Digitrax system but not NCE.

                          --Randy

 

The RS2 worked correctly when programmed to address 6207.  Only the Paragon 2 decoder seems to have issues with the address 6207.  I do not believe this is a system problem.  

 

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