Maybe decoder is dead?

[rva1945]

It was gently running at low speed then it stopped, lights out.
It is detected by the programmer, brand, address, everything. When reading or writing CVs it moves (jerks as expected) and the light flashes so connections are ok.
In analog mode, i.e. with DC it runs and even the light effect works.
But does not respond to DCC commands.
Other locos run ok on the tracks.
What happened?

I'm running DCCpp in an Arduino Mega.

I want to reset it, but the CV 8 (210 is the reset code) appears disabled in JMRI. When sending the write command from the Arduino IDE Serial Monitor, it returns -1 which means could not write the value.

?

[John]

I would try to find someone with either an NCE or Digitrax setup, and try to get the decoder reset done there .. I'm not familiar with the arduino setup ..

take a look at the motor voltage settings    vstart, vmid, etc ..

[mu26aeh]

Need some more information.  What scale, engine, make, decoder do you have ?

[C855B]

Frankly, the default in a situation like this is to reset the decoder through CV8 and start over. Until you have a way to do that, we're going to be spinning wheels.

Now if you're running JMRI, Decoder Pro should have everything you need, including the ability to reset. I am puzzled why you're getting an indication you cannot do this.

[peteski]

Just like others said we need more info. Also being able to do a factory reset is pretty much required troubleshooting step.

If the decoder responds to CV read commands and the motor twitches that to me indicates that both the microprocessor (the brain of the decoder) and the motor driver circuitry are working correctly.  If it runs on DC (and lights work too) that confirms that all the decoder circuitry works ok. In DC mode the decoder does not magically bypass all the electronics inside - it still utilizes all the same circuitry which is used in DCC mode.

The problem might be a simple as you addressing the loco using a short instead of long address or vice-versa.

[rva1945]

Hi:

I'm using JMRI to program the decoders. This one was not included in the list of identified decoders so I downloaded its xml configuration file from a site, imported it and it was since identified by JMRI.

I couldn't write into CV8 as its tag in the xml file had readonly=true in its properties, which I deleted.
I deleted the entry from the roster, reinstalled the xml config. file, and then I tried to reset writing 210 in CV8, as specified in the manual.  don't know if that worked or not because it seemed to freeze, but some say that is the way the reset works: you don't actually write that value, just trying to do it forces the reset to factory values.

Suddenly, the loco was identified as number 3 (was 550 before), and everything worked fine since. Changed the loco back to 550 later.

In minutes I'll post some pictures and details about my homemade control console.

Thanks,
Robert

[C855B]

I'm glad we were able to put you in the right direction, although slightly surprised we were of help given the obvious depth of your work in JMRI. Mostly curious - did you try the JMRI Yahoo group first?

[rva1945]

No I didn't try that group, perhaps I should have done it and it would have saved me time. Now the FT is slowlo pulling all the freight cars "zero defect".

R.

[John]

I bet the JMRI folks would appreciate the .xml file as well, if its under GPL license .. it's a great group of people, and they are always looking for contributors .. come check us out ..

[rva1945]

John:

I should tell the LDH manufacturer to do it.

[peteski]

You still haven't divulged the manufacturer and model of the decoder. 

I could look up using 210 for reset in CV8 (as that is unusual), but I'm lazy.    You are correct, CV8 in all the decoders is a non-standard register. You can read it and write to it but it will not retain the written value (it always comes back with its preset value). But it does recognize the value written to it and responds appropriately.

[rva1945]

You still haven't divulged the manufacturer and model of the decoder. 

You want it you got it, but the site is in Spanish:

http://www.ldhtrenes.com.ar/decoders.htm

It runs very well.

[peteski]

You want it you got it, but the site is in Spanish:

http://www.ldhtrenes.com.ar/decoders.htm

It runs very well.

Thanks Robert!  Until now I have never heard of LDH. It is always good to learn about (new to me) manufacturers of DCC decoders.

[rva1945]

Thanks Robert!  Until now I have never heard of LDH. It is always good to learn about (new to me) manufacturers of DCC decoders.

In this link you can download the  Manufacturer ID codes as assigned by the NMR:

http://www.nmra.org/sites/default/files/standards/sandrp/pdf/appendix_a_s-9.2.2.pdf

LDH is 56, from ARG.

[peteski]

Thanks - I do know about the manufacturers ID list but until just now I didn't know the manufacturer. Besides, I never really tried to go down that list to check wabistes of all the manufacturers listed.  But it is good to know someone who actually uses some obscure (to USA modelers) decoder.