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

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Posted by richhotrain on Wednesday, September 23, 2015 12:16 PM

rrinker

 At least it's reproducible. The most impossible to solve problems are ones that do not happen consistently.

                   --Randy

Randy, your question remains unanswered as to whether CV18 values other than 63 result in the same problem.
 
Rich

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Posted by rrinker on Wednesday, September 23, 2015 12:43 PM

 Well, if someone wants to try addresses with every combination of CV18 - so 255 different addresses... that would be the only way to absolutely validate things. If I had a Paragon 2 loco I could try it with Digitrax, might take a week or so, doing a few at a time until I got through it, but since I currently have no layout I have the time for that. Not expecting someone to actually take all that time to try it - one would THINK that now that BLI is aware of an issue like this existing, and acknowledges that they can replicate it, that when they do have a fix they woudl test all possible bit patterns to make sure there isn't some other value besides 63 that causes a problem. Or perhaps the cause will be revealed to be something so obvious that the fix is pretty much guaranteed to work - like they are calling subroutine A when it needs to be subroutine B.

                 --Randy


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Posted by Anonymous on Wednesday, September 23, 2015 2:15 PM

I replied to BLI, asking if it was repeatable across all DCC systems that they have, and asking that the service tech forward the link I sent them from this forum thread to the software engineer.  

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Posted by Anonymous on Wednesday, September 23, 2015 4:03 PM

rrinker
Hmm, something else to try, when it only runs backwards in 128 step mode, is that with the headlight on or off?

Both, and the directional headlight performs as if the locomotive was told to run in reverse.

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Posted by richhotrain on Wednesday, September 23, 2015 4:48 PM

BMMECNYC

  

rrinker
Hmm, something else to try, when it only runs backwards in 128 step mode, is that with the headlight on or off?

Not sure how to interpret your answer.  
 
When you press the 128 speed witht the Direction button set to forward but the loco runs in reverse, is the headlight on or off?
 
When you press the 128 speed witht the Direction button set to reverse and the loco runs in reverse, is the headlight on or off?
 
Rich

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Posted by Anonymous on Wednesday, September 23, 2015 9:00 PM

The E7 only has the forward light, and if I recall correctly, it is dimmed in both cases, which is expected for the direction of travel.  In the case of the SW-7 I tried, the reverse light was lit and the headlight was dimmed, as you would expect if rule (17?) lighting is setup, also reguardless of the direction selected on the throttle.

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Posted by richhotrain on Thursday, September 24, 2015 5:09 AM

rrinker

28 and 128 speed steps use different packets. 14/28 speed steps use the same packet in differnt ways, which is why you have the bit in CV29 that tells the decoder which option to use. 128 speed step packets automatically tell the decoder to use 128 speed steps, the setting of CV29 has nothing to do with this. 

The reason that I brought up CV29 is because CV29 controls the direction of travel, forward or reverse.  If a long address such as 6207 results in a reverse travel direction when 128 speed is selected, then the value of CV29 apparently has been increased by 1 even when the Direction button has been toggled to forward.

Rich

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Posted by richhotrain on Thursday, September 24, 2015 6:09 AM

BMMECNYC

The E7 only has the forward light, and if I recall correctly, it is dimmed in both cases, which is expected for the direction of travel.  In the case of the SW-7 I tried, the reverse light was lit and the headlight was dimmed, as you would expect if rule (17?) lighting is setup, also reguardless of the direction selected on the throttle.

 

OK, I decided to try it myself, using a Paragon 2 steam engine with a head light but no rear light.
 
Using 28 speed, the head light is dim in neutral, bright in forward, off in reverse.
 
Using 128 speed, the headlight is dim in neutral, off in forward and reverse. (of course, the loco does not travel forward when the Direction button is toggled to forward).
 
So, the headlight always performs in relation to its movement.
 
Rich

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Posted by richhotrain on Thursday, September 24, 2015 6:14 AM

I started to take up Randy's challenge to test every long address in which CV17=216. Unfortunately, there are 256 such addresses (6144 through 6399).  I am able to change the long address POM by changing the value of CV18, while leaving the value of CV17 set at 216. Each change of address takes about 1 minute, so it would take about 4 1/4 hours to test in this manner.  I did 20 changes between 6206 and 6225, and only 6207 failed the test.  

If Randy will supply me with beer and pizza, I will continue the test.  Laugh

BeerPizza

Rich

Edit Note:  I have corrected the statement made in this reply.  I meant to test various long addresses in which CV18=63 was the constant, but I mistakenly tested long addresses in which CV17 was the constant.

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Posted by rrinker on Thursday, September 24, 2015 7:16 AM

 Accuracy of the test may suffer as number of beers goes up, but sure. Just after you are done you need to send me the loco so I can repeat the tests using Digitrax.

                    --Randy


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Posted by Anonymous on Thursday, September 24, 2015 2:40 PM

I tested some DCC addresses today, here are the results:

DCC Address (CV 17, CV 18)

Checking to see if glitch occurs accross full range of possible CV 18 values of 63

831 (195, 63) Glitch present

9791 (230, 63) Glitch present

Randy's and/or Rich's something about binary theory from above somewhere:

6080 (215, 192) Glitch not present

6015 (215, 127) Glitch not present

6143 (215, 255) Glitch not present

BLI confirmed that this occurs on Digitrax as well by email.

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Posted by richhotrain on Thursday, September 24, 2015 4:18 PM

BMMECNYC

I tested some DCC addresses today, here are the results:

DCC Address (CV 17, CV 18)

Checking to see if glitch occurs accross full range of possible CV 18 values of 63

831 (195, 63) Glitch present

9791 (230, 63) Glitch present

Well, there you have it.  All of the long addresses in which CV18=63 contain the glitch.  There are 39 of them, beginning with the long address of 063 and each multiple of 256 thereafter (e.g., 319, 575, 831,....................9791).

In my earlier reply, I misspoke when I related my test.  I mistakenly tested CV17 as the constant, not CV18 as I meant to do.  I corrected that earlier reply.

Rich

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Posted by Anonymous on Tuesday, September 29, 2015 6:50 AM

richhotrain
 
rrinker

28 and 128 speed steps use different packets. 14/28 speed steps use the same packet in differnt ways, which is why you have the bit in CV29 that tells the decoder which option to use. 128 speed step packets automatically tell the decoder to use 128 speed steps, the setting of CV29 has nothing to do with this. 

 

 

The reason that I brought up CV29 is because CV29 controls the direction of travel, forward or reverse.  If a long address such as 6207 results in a reverse travel direction when 128 speed is selected, then the value of CV29 apparently has been increased by 1 even when the Direction button has been toggled to forward.

 

Rich

Isn't CV29 where the 28/128 speed step data is stored?  Have we tried setting CV 29 to 35 for reverse direction operation?  

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Posted by richhotrain on Tuesday, September 29, 2015 8:41 AM

BMMECNYC

Isn't CV29 where the 28/128 speed step data is stored?  Have we tried setting CV 29 to 35 for reverse direction operation?  

Interesting question.  Interesting experiment.
 
As a reminder, both BMMECNYC and I operate with NCE PH-Pro 5 amp systems.
 
At the outset of this experiment, I did not know for sure how CV29 interacts with the Direction button and the 28/128 button on the ProCab.
 
Here are the results of my experiment.
 
I began by placing a Paragon 2 loco on the Programming Track and programmed a long address of 6207 and set up the basic decoder configuration (CV29) for forward direction, 28/128 speed, long address.  Then, I checked the value of CV29 on the Programming Track.  As expected, CV29=34.
 
I placed the loco on the main with the Direction button Forward and the 28/128 button at 28.  As expected, the loco moved forward.  Then, I pressed the reverse button with the speed still set at 28.  As expected, the loco moved in reverse. At that point, I placed the loco on the Programming Track and checked the value of CV29.  It was still CV29=34, although I expected CV29=35.  So I checked a non-Paragon 2 loco, same result.  
 
So, apparently CV29 determines the front position of the loco, but toggling the Direction button on the main does not change the value of CV29.  CV29 determines the position of the loco, but the Direction button controls the motion of the loco.
 
Then, I continued to experiment with the Paragon 2 loco on the main, toggling the speed button to 128.  At the 128 speed setting, the loco always ran in reverse, regardless of the position of the Direction button.  The preset value of CV29 never changed.  So, my conclusion is that when the speed button is toggled to 128, the Direction button is somehow defeated.
 
Go figure.
 
Rich

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Posted by rrinker on Tuesday, September 29, 2015 10:40 AM

No, CV29 has nothing to do with 28/128 speed steps. It DOES switch between 14 and 28 speed steps. The 128 step packets are completely different and the decoder automatically detects them. The inclusion of "28/128" in the description for bit 1 of CV29 is really a mistake, it only switches between 14 and 28. See one of my earlier posts in this thread - you can verify this for yourself.

                  --Randy


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Posted by richhotrain on Tuesday, September 29, 2015 10:44 AM

Randy, I think most of us get that, but what I was saying is that CV29 is apparently not part of this specific problem.  It seems more to do with the Direction button or the failure to activate the toggle effect of the Direction button in conjunction with 128 speed steps.

Rich

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Posted by DigitalGriffin on Tuesday, September 29, 2015 2:18 PM

Whatever the problem, the programmer at BLI will likely have a patch in a month or so.  (At our company critical patches are usually out < 1 week but I doubt BLI has the resources we do)

There's nothing else to do but wait.

Don - Specializing in layout DC->DCC conversions

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Posted by richhotrain on Tuesday, September 29, 2015 2:48 PM

DigitalGriffin

Whatever the problem, the programmer at BLI will likely have a patch in a month or so.  (At our company critical patches are usually out < 1 week but I doubt BLI has the resources we do)

There's nothing else to do but wait.

Agreed.  
 
This is pretty much of an intellectual pursuit at this point. Inquiring minds want to know stuff.

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Posted by rrinker on Tuesday, September 29, 2015 6:45 PM

 Hence all the bit pattern tests, to see if it was limited to CV18=63=00111111 or other bit patterns caused the same problem. So far it looks like only when CV18=63 is there a problem. That's the sort of info that could help a developer track down the cause of the problem, otherwise is't just a curiousity. It's clearly beyond fixing just by setting CVs.

                    --Randy

 


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Posted by richhotrain on Wednesday, September 30, 2015 4:23 AM

As part of that intellectual curiosity, I would like to know what caused the error, but that may likely never happen.

It sure does seem like a very obscure programming error to only affect the 128 speed step on a long address in which CV18=63.

Rich

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Posted by Anonymous on Sunday, October 16, 2016 1:38 PM

One year an no email from BLI.

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Posted by richhotrain on Sunday, October 16, 2016 1:42 PM

BMMECNYC

One year an no email from BLI.

 

Call them.

Rich

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Posted by Anonymous on Tuesday, October 18, 2016 1:37 PM

Well it seems they think they have it fixed.  The nice lady on the other end of the phone call seemed to think they fixed it at some point (yahoo likely conveniently deleted their email informing me of such developments, which happens from time to time).  She will talk to Joe (see my previous email in post form) and see if the replacement decoders they have will fix the problem.  If so, they will send them to me.  

Any more issues and the locomotives are getting TCS WOW sound decoders...

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Posted by richhotrain on Tuesday, October 18, 2016 7:09 PM

That's very good news.

Keep us posted on the outcome.

Rich

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Posted by Anonymous on Friday, October 28, 2016 7:23 AM

4 new Paragon 2 decoders should be arriving in the mail today (one for each Paragon 2 locomotive I own). 

If they don't work I will likely replace All 4 decoders with TCS Wow sound or Loksound, and return all 8 decoders to BLI. 

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Posted by wjstix on Friday, October 28, 2016 7:43 AM

Just to be sure I'm following...when the engine / decoder is set for 128 speed steps, it runs in reverse of the direction it should, right? So, have you tried at that point reading CV29, and reprogramming that CV to one number higher (or lower) and see what happens? So if CV 29 is 34, change it to 35? If changing one CV has somehow reversed the polarity of the DC power going from the decoder to the motor, I'd think changing CV29 by one number would fix it...or just swap around the wires going to the motor.

Stix
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Posted by Anonymous on Friday, October 28, 2016 8:40 AM

wjstix

Just to be sure I'm following...when the engine / decoder is set for 128 speed steps, it runs in reverse of the direction it should, right? So, have you tried at that point reading CV29, and reprogramming that CV to one number higher (or lower) and see what happens? So if CV 29 is 34, change it to 35? If changing one CV has somehow reversed the polarity of the DC power going from the decoder to the motor, I'd think changing CV29 by one number would fix it...or just swap around the wires going to the motor.

 

Stix,

No.  That was literally the first thing I tried over a year ago.  It only runs in reverse.   CV29 has not effect on this problem.  On 28 speed steps there are no issues.  The problem has something to do with CV 18 having a value of 63.  No idea why.  It has been confirmed on my NCE system, Rich's system, and I believe Randy's system as well. and both NCE and Digitrax systems at BLI.  Of the 10,000 possible addresses, 36 have this glitch. 

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Posted by richhotrain on Friday, October 28, 2016 10:36 AM

BMMECNYC

 

 
wjstix

Just to be sure I'm following...when the engine / decoder is set for 128 speed steps, it runs in reverse of the direction it should, right? So, have you tried at that point reading CV29, and reprogramming that CV to one number higher (or lower) and see what happens? So if CV 29 is 34, change it to 35? If changing one CV has somehow reversed the polarity of the DC power going from the decoder to the motor, I'd think changing CV29 by one number would fix it...or just swap around the wires going to the motor.

 

 

 

Stix,

No.  That was literally the first thing I tried over a year ago.  It only runs in reverse.   CV29 has not effect on this problem.  On 28 speed steps there are no issues.  The problem has something to do with CV 18 having a value of 63.  No idea why.  It has been confirmed on my NCE system, Rich's system, and I believe Randy's system as well. and both NCE and Digitrax systems at BLI.  Of the 10,000 possible addresses, 36 have this glitch. 

 

I totally agree with BMMECNYC.  It was a programming flaw in that particular decoder series that only affected certain long addresses.  CV29 did not play a part. Go back and read through page 3 of this thread for a fuller discussion.

Rich

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Posted by rrinker on Friday, October 28, 2016 12:47 PM

 I'll attempt to explain my theory a little better.

28 and 128 speed steps use the same setting in CV29. It is up to the decoder to interpret the differences in the NMRA DCC packet to tell if it is a 28 speed step packet or a 128 speed step packet.

 The 128 speed step packet is completely different from a 28 speed step packet, 128SS uses the extended packet format. So this can easily explain why the loco worked fine with 28SS but not 128SS - there are different routines to decode and respond to the packets. Now, thre is a type of extended packet that actually encodes a direction, among other possible commands, in 3 bits. The pattern for reverse though is 010, forward is 011. Maybe with soem more digging the error in BLI's decoder will reveal itself, but it wasn't quite this obvious. At issue was CV18 having a value of 63, bit pattern 0011 1111. Somehow this bit pattern for the address was being masked against the wrong part of the extended format packet and makign all speed commands appear to be ones for the reverse direction. A different pattern in CV18, thus a different long address, seemed ok, as did using 28SS so avoiding the extended format packet altogether.Still an interesting puzzle as to the exact cause, but only BLI will be able to determine that as no one else has the source code for their decoders to examine and see where the mistake may be. I AM pretty confident that this is all it is, a slight coding error, perhaps the wrong variable used, or bits transposed somewhere. That is only shows up when CV18 has a specific value, it's easy to see how this could go overlooked in testing. With the way CV17/18 work for long addresses, it's only very specific addresses that end up with CV18 = 63, while thousands of other addresses have a different value for CV18. I can't imagine ANYONE testing every possible long address to validate their code.

                     --Randy

 


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Posted by Anonymous on Saturday, October 29, 2016 5:20 PM

rrinker
I can't imagine ANYONE testing every possible long address to validate their code.

It took long enought to go through and test half of the 36 suspect addresses to check for the error.  I cant imagine trying to test ~10k address.  One would go bonkers.

Decoders arrived in my mailbox today.  Might install and test one or two tomorrow.  Will let you guys know.

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