Newbie Question - DCC and LGB

Greg Elmassian

Greg Elmassian

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I do not agree that resetting by writing to a CV is bad, in most cases it's the only way.

(when you have a chance I would love to read the passage you are referring to)

When in service mode, only low current is used, so #1 cannot be true IF you are running service mode. (JMRI should indicate if it cannot read, i.e. go into service mode)
If you are not in service mode you CANNOT read back from the decoder. I'm still not convinced you are in service mode.

I'm telling you to reset the decoder, sometimes everything is right but the decoder is locked up. Also there's very few ways that the decoder would not have SOME output to the motor.

Yes, another theory could be that you are in service mode, but then the functions could not be operated, and you stated that they work.

Something is still fishy with the "story"... I can give you step by step to debug this, but I don't want to be "fighting" statements like resetting by CV is not recommended, that statement by itself is just not true, so it must be out of context or not properly understood or not quoted accurately.

My recommendations would be:

1. verify service mode
2. write a CV and then read it back to guarantee you are actually in service mode.
3. reset the decoder
4. then verify the operation of the motor, or debug the electrical problem.

Greg
 
PhilP

PhilP

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I'm with Greg..
Resetting the decoder will not wipe the sound profile loaded into it. - In case you are worried about that. We are saying reset the basic settings, NOT reload the firmware into it.

As Greg says, there are a few things that could be stopping motion:
Mechanical lock-up. NO, it runs analogue.
Output transistors on decoder blown. NO, it runs analogue.

Your tests would *seem* to suggest the decoder is doing what it is told, but settings are such that it does not do what you expect. - So setting these to known starting values seems like a good way to proceed? Perhaps?? Maybe???
 
John S

John S

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Back to Basics!

Which H Bridge controller? One of these? Then the notes below are applicable, or if something else?
116419_51322668dc5dfdae2a9ae27295b1c3b1.png


116421_48ca9adaf0c03b1187a3040cba767347.png


They are essentially the same....

116423_43131bfa5c3158ced9d8b567a1c287f9.png


From the screen above, Green Button, activates the 4 LED's at A & B?

Green lettering at the bottom........

By default, little Blue Dot Programming Track...are you connecting to the "B" Terminals?

As to which decoder, will deal with in another post, seems highly unlikely will be the one selected, it's a HO decoder, as for lights, JMRI assumes you are using the NMRA definition for lights which is F0, large scale decoders, Lights are is usually F9....

Back to Basics, confirm and verify the right Programming Mode is selected and the correct "A" or "B" is being used.........
 
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stockers

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It was I that suggested that a reset of the decoder may be unwise. I am aware of several people that have done resets and have lost their board for ever. As I stated at the time, many people seem to do them all the time and get away with it. A good look at the CVs often solves the problem. I see a possible problem here that the user has opted for a non LGB/Massoth template in JMRI - different companies use some CVs very differently.
 
John S

John S

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Stockers you are indeed correct, using JMRI to program a large scale decoder is a fraught experience at the best of times.

To cite an example to confirm Stockers advice, using a decoder profile from JMRI for a Massoth XL-M1 to reset an LGB 55028 decoder, completely and utterly "bricked it", was sent to me, and it took me the best part of three hours to "unbrick it", so the short answer is, unless you know the insides of a "ducks a**s" about the decoder template from JMRI, tread with extreme caution, and if you have to do, a decoder reset, use the single CV programmer!

JMRI's Decoder Pro and Decoder Pro3, have got to be, the worst possible scenario for inexperienced users...................plus the program itself is a pile of carp, and that was from an American user on this Forum!
 
idlemarvel

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Stockers you are indeed correct, using JMRI to program a large scale decoder is a fraught experience at the best of times.

To cite an example to confirm Stockers advice, using a decoder profile from JMRI for a Massoth XL-M1 to reset an LGB 55028 decoder, completely and utterly "bricked it", was sent to me, and it took me the best part of three hours to "unbrick it", so the short answer is, unless you know the insides of a "ducks a**s" about the decoder template from JMRI, tread with extreme caution, and try to avoid a decoder reset!

JMRI's Decoder Pro and Decoder Pro3, have got to be, the worst possible scenario for inexperienced users...................plus the program itself is a pile of carp, and that was from an American user on this Forum!
So it is not so much resetting a decoder which is bad, rather using JMRI to do the reset is bad. Having struggled with JMRI in the past I can well imagine that is the case.
 
John S

John S

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Again correct, resetting the decoder can/has cured many an odd fault. It's the use of JMRI than can/has caused problems, most of the large scale decoder templates that reside in JMRI, are next to useless and in some cases positively dangerous!
 
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robboz4

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Wow - seemed to have opened up a can of worms about the reset. I did find some LGB templates buried under Massoth, but not sure which one matches the 25552. So a very simple question that I can’t seem to find an easy answer for that might help me resolve this.
I know the track is in service mode when running DCPRo decoder from JMRI, as it tells me in a green font at the bottom of the screen. How do I take my Arduino DCC++ into main mode?
I’m just trying to get a test setup on small loop of track to try it out before moving on to possibly adding decoders to my older engines and starting new hobby.

The H bridge was a purchase of Amazon rated at 30volts 5 amps. I’m using one port only. If I put an analog engine on there and use the software (JMRI OR DCC Controller) to turn on the power to the track the engine runs. So once again I assume it is sufficiently powering the track.

Thanks again for all the help. Once I get it running hopefully I can contribute in the future to the group.
 
John S

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This H Bridge Controller?...Pololu - MC33926 Motor Driver Carrier

From drop down menu select Single CV Programmer, enter CV7 make note of value, enter CV8 make note of value, these will help towards identifying the decoder.

Picture post#47, Blue Dot, move mouse over to the programming on main............. .

Drop down Menu, Settings, Preferences, change options for DCC++, Command Station.............

As ever the JMRI website has links to getting started and using the program................JMRI Manual: Index, as a new user it would be a worthwhile use of your time to read and study the manual in great detail, even to download it, and print the manual out, as source of reference.

JMRI requires a great deal of time to explore, and to understand how it works.

One of the best sources of information on DCC++ can be found here, Introducing DCC++ ---a complete open-source DCC station and interface

25552 Factory-installed MTS Decoder (probably a 55021/22 variant) on board for analogue and digital, eight function sound card (probably a 65xxx type)
 
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robboz4

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Hi!

The H bridge was this cheap one:

https://www.amazon.com/gp/product/B00CAG6GX2/ref=ppx_yo_dt_b_asin_title_o00__o00_s00?ie=UTF8&psc=1

And I think it might be a problem. In using the DecoderPro ( JMRI 4.14 on Java 1.8.0-151 it doesn’t say DecoderPro 3 in the about box) I get different values when trying to read CV values with the single CV Programmer panel. The first read of CV 107 gives 154. Then trying to read CV108 I get a 308 error, but then a successful read of 52. But after that successful reads yield different values, including for CV107. And there are many 308 issues when trying to read any value. As I know CV 1 should be the address of 3, I should not be getting 108.
Also using the traffic monitor after a few turning on and turning of sounds I see continuous traffic of the last command. Turning off the power doesn’t stop it. So not sure whether that’s a bug in the JMRI code, the Arduino DCC++ code.
I have captured a log of the output. Should I file a report?

Thanks for the tip on switching the track from service to main. I thought that was it, but as the symptoms didn’t change thought I had it wrong. Especially as both service and operations modes are online ( green text in lower panel). I would have thought the status would change on the track mode you wanted. I.e track is now in operation mode.
Yes there is a lot read and digest on JMRI, but like I said I was looking for a quick easy way to check out DCC++ before investing heavily with stuff I had... LGB Engine and a spare Arduino. So far new investment $7 on Amazon.

What are your thoughts on the H bridge?

Thanks and cheers!
 
John S

John S

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Ah! the mystery sheds some light, that motor controller is troublesome, post #72 here, Introducing DCC++ ---a complete open-source DCC station and interface, gives a very detailed explanation.

Error Code 308 - No acknowledge from locomotive
At the end of a CV read or write operation, the locomotive replies ("acknowledges") to the command station using a pulse of current.

If that pulse isn't seen, some command stations provide this error message.

For getting started, use this link, tried and trusted.

Initial JMRI and DCC++ Controlle

When more experienced could move onto this.

My Experiments with DCC ++ d

I have used these as a base point for my own various experiments which can be found here ,Raspberry Pi Zero Controlling Things - G Scale Central, start from around post#31.

This board is tried and trusted, ideal for a beginner to get started with DCC++.

116581_51322668dc5dfdae2a9ae27295b1c3b1.png
 
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robboz4

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Thanks again. Looks like I'll invest in a new motor control board.

I can't find the DEEK one shown above. The Deek-robot web site is under construction and it points to AliExpress for the board, and that web site has no products. However, if I search for motor shield I get a lot of entries but none of them say DEEK. And they are even cheaper than the one I bought and for an arduino plugin board that's amazing. However, I'm not sure they will work given my recent experience. Here's an example:


Aliexpress Motor Shield Example

Open source etc.. But for $4.00 with a shipping time 35 Day who can go wrong!

Will post more when I have decided which board to buy!


Thanks!
 
PhilP

PhilP

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Go back to the instructional sites, and choose a *known to work* motor-shield..

Many (of the cheap ones) are not capable of switching fast enough to faithfully reproduce the DCC signal. - That is very probably your problem. :think::think:
 
John S

John S

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This is the correct board to order....US $4.7 11% OFF|L298P L298 Shield R3 DC Motor Driver Shiled Board For Arduino UNO Module 2A Dual Full Bridge H Bridge 2 Way Relay 5V 12V-in Integrated Circuits from Electronic Components & Supplies on Aliexpress.com | Alibaba Group

Whilst you are waiting it's delivery go here, DccPlusPlus/Documentation, download or better still print out the document, note the modifications that are required to the underside of the motor shield, the diagram is for a Arduino Motor Shield, the Deek Robot Motor Shield is essentially the same beast, just wearing another coat, see comment in post #43.


The one you have linked from post #52 will not work, wrong pin assignments.
 
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beavercreek

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Decoder Pro and JRMI.
I have used it with many LGB, ESU, Massoth, Lenz, QSI, Soundtraxx, Digitrax and TCS.
I use the Mac version and have also tried it using Windows on a Mac (Parallels and Boot-camp).

It has always behaved well and barring the fact that it is not as accomplished at programming sound as the dedicated software/module packages (eg ESU's Lokprogrammer or Massoth's PC module), in fact Decoder Pro/JMRI will not allow sound file programming. That is when I use the manufacturers software/module instead of Decoder Pro.
I have yet to 'brick' a decoder.
Also, to be fair, there can even be problems and challenges sometimes with sound files using the manufacturers own programming software.

So in defence of Decoder-Pro/JMRI.... the interface is more graphical (although ESU and to a certain extent Massoth have made strides to make their software a little more user friendly)... it deals with many makes and models of decoder (just make sure that you choose the correct template for your decoder).

Just my point of view based on about 200-300 uses of the program to alter decoder behaviour
 
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PhilP

PhilP

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just make sure that you choose the correct template for your decoder.
There's the rub, and possibly part of many first-timers problems with the software?? :think::think:

Just when they need it to show exactly the correct template, it probably doesn't. - But the software 'identified' the decoder, so they continue. :oops:


You can't beat just reading the manufacturer id, going to the NMRA listings, then 'Googling' for an image, to see if it matches what is in the loco.
:nerd::nod::nod:
 
beavercreek

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There's the rub, and possibly part of many first-timers problems with the software?? :think::think:

Just when they need it to show exactly the correct template, it probably doesn't. - But the software 'identified' the decoder, so they continue. :oops:


You can't beat just reading the manufacturer id, going to the NMRA listings, then 'Googling' for an image, to see if it matches what is in the loco.
:nerd::nod::nod:
:cool::cool:
 
JimmyB

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It would seem if I ever move to DCC I am going to have a lot of questions, currently all this goes straight over my head.
 
stockers

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The thing is Jimmy, you don't actually have to do any of this to enjoy DCC - unless you want to. Nearly all suppliers will supply a decoder set up for you. All you need to do is change the address - easy.
Everything else is just playing, but why not, it can become part of the hobby - but only if you want it to.
 
idlemarvel

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It would seem if I ever move to DCC I am going to have a lot of questions, currently all this goes straight over my head.
That's because R robboz4 wanted to build his own system which is what you might call diving in the deep end. If you know how to swim that's fine but if you have only watched swimmers and think to yourself that looks easy then it's probably a bad idea. :)
If you want to start DCC I would suggest a starter set from a manufacturer which has all the bits that you know will work together - power supply, command station, controller and loco with decoder - to get an understanding of how DCC works hands on and the benefits it can bring. Many of the issues with DCC are let's say not complete compatibility between manufacturers, so a starter set avoids that issue until you have the experience. I don't mean to sound patronising, this is how I started with Hornby OO digital starter set many years ago.
 
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