DCC Onboard Found cv 130 and 131,

[brokenrail]

Hello Bachmann ,
Just though of posting the inaccuracy of the dcc on board cv list since the electrical noise and performance of this decoder is pathetic at slow speed .Runs better at

slow speed on dc though.Found cv 157 which changes the locos direction with odd and even number pattern that does this.Now I FOUND cv131,132 and 130

have a positive effect on how it runs almost like a bemf.Noticed this up a grade at slow speed .Would not stall once adjusted.Anybody find any more?Or even a

better question when dealing with motor performance with these dcc onboard decoders that are not the plug in type but a complete board type Why are these

not listed when it deals with performance which with trial and error makes it run better? Found 131 by accident wile I was dialing up the volume on the prime

mover on a sound value diesel to around 200 in service mode not realizing that the gp 9 was on the same rail at the time .Then noticed the gp 9 would not move hardly even at full throttle from a dead stop like cv 3 acell rate was turned up to

255 .So I backed it off to 90 programming on the main.Shut power down and restarted power .Now it ran pretty smooth between speed steps 1 and 10 with a

lot less electrical noise.Started my trial and error with the cv's before and after and there also was a change in a positive way.I am running on 128 speed step

mode with dc turned off.I do not know what these cv's are ,but  I  do know that they are there and not listed at all on this site for the dcc on board locos.Be

nice to know there technical name, and  could they create a problem if adjusted? Better to be safe then sorry.
Johnny Adam

[brokenrail]

 

[Len]

You can find the NMRA list of CV's here: http://www.nmra.org/sites/default/files/standards/sandrp/pdf/s-9.2.2_decoder_cvs_2012.07.pdf

Note that CV's in the range 112 - 256 are "Reserved for manufacturer use" and completely "Optional". Which means Bachmann may not have publicized them because they didn't want people changing the default settings.

Len

[Hunt]

Johnny,

DCC decoders have undocumented CVs. These are the CVs that the end user should not change.  The decoder manufacturer is not going to provide info about these.

[rogertra]

Johnny,

DCC decoders have undocumented CVs. These are the CVs that the end user should not change.  The decoder manufacturer is not going to provide info about these.

But if you use a more advanced DCC system that can utilise JMRI, then you get to change these CVs if you want to.

Cheers


Roger T.

[Hunt]

Click Here
It is what is prebuilt and provided for use by JMRI Decoder Pro, for Decoder Family: E-Z Command decoders 2 function decoder. 

[brokenrail]

cv 130 and 131 work hand in hand with the numbers .They can be overridden by  cv 2 , 3, 4..But if you leave those at a 0 value and work 130 and 131 it will run tie to tie much better at speeds steps 1-3 and will run up my grades without stalling at those speed steps.So it seems there is a bemf cruise controll type of effect here that is not mentioned in the provided  default cv list Without USING THEM I get that annoying buzz from the non silent decoder and will not run like it should unless you run cv 2 up to 20 .Then you lose your slow speed steady creep .It sounded bad and ran bad out of the box and it was going to get returned ,but I gave it a chance.Iuse a Bachmann Dynamis system that is very good at making cv programming easy for me
When using them it runs pace with my sound value s4 that runs as any hi end when tweaked for slow speed.I tried using the 130 and 131 cv's on a older  07 release dcc onboard sd40-2 and ran the same number I used with the gp 9 and the effect was not the same.There was an effect ,but it was not in the positive way with the gp 9. Maybe they are unique to this new gp 9 board???
There was a mention about 2 functions.I only see one.The lights are directional ,but the unique thing with the gp 9 is the reverse  light does not go out ,but it dims like the sound value.In my opinion they should list all the cv's ,but label certin ones precautionary in that there may be a undesirable effect .Especially since they do not list these that do a very positive effect . Transparency in this case weather it be designed for jmri or what ever would benefit and also would be appreciated by the end user  then to be left in the dark .Just a opinion and some great findings that should be listed what ever they are called.Try 130 and 131  you will see why .
Johnny Adam

[Hunt]

Johnny,

There is not a CV 130, 131, 132 or 157 in the DCC ON BOARD decoder.

The decoder is not designed to use CV Binary bit 7 being other than 0

Thus
Programming CV 130 actually changes the value of CV 2
                    CV 131 actually changes the value of CV 3
                    CV 132 actually changes the value of CV 4
                    CV 157 actually changes the value of CV 29

If the value programmed is in the valid range for the CV

[brokenrail]

That is interesting Thanks.Strange thing  about is when I go into my programming procedure with 2,3,4 with the dynamis . I do not get the same effect with it. If I bump up cv 2 it will over ride  what ever is in cv 3 completely.So speed step 1 is 20mph not 5mph  estimated of course. When I USE CV 130 AND 131.Zero out 2,3,4 it will creap along and not stall in a 2% grade.It acts more like it did have cv,5 and 6 set like on a soundtraxx decoder.I leave 157 alone after a reset when I tinkered with 130 and 131 and the same effect occurred with the great slow speed controll. It surprised me so .I tried it a few more times thinking that it was a goof and no it was confirmed.Maybe it is the dynamis playing tricks on me with only this loco?
Johnny

[Hunt]

The Bachmann DCC ON BOARD decoder is a basic 28 speed step decoder. Setting your command station for 128 speed steps and then sending out commands for step 1, step 2, step 3 or step 4 will all cause this decoder to produce speed 1 of 28.  Sending step 5, 6, 7, or 8 will result in the decoder producing speed 2 of 28 and so on.

I don't have the interest to make time to determine how this old decoder is using values in CVs 2, 3 and 4 with its internal speed curve or to get into the details of Dynamis and this decoder.

[brokenrail]

Understandable,
Be great to be able to reply to you.

[jward]

Johnny,

There is not a CV 130, 131, 132 or 157 in the DCC ON BOARD decoder.

The decoder is not designed to use CV Binary bit 7 being other than 0

Thus
Programming CV 130 actually changes the value of CV 2
                    CV 131 actually changes the value of CV 3
                    CV 132 actually changes the value of CV 4
                    CV 157 actually changes the value of CV 29

If the value programmed is in the valid range for the CV

very interesting,  all of the cvs that johnny referred to are 128 higher than their corresponding cvs that they apparently control. if there is no sevehth bit in a Bachmann decoder that is recognized as such, would you not be in fact programming the lower numbered cvs by default? 2 to the 7th power is 128 thus bit 7 as a value of 1 would add 128 to the value programed.

[brokenrail]

Mr Ward,
It seems you are correct ,in this idea.I stumbled upon this first with cv 131 programming the prime mover volume on a sound value loco with address 3 and left the dcc loco on the rail when doing this.I SET 131 to a value of 200 then tried running the dcc onboard loco and it just sat there and buzzed and would not move at wide open throttle like cv 3 was set to 200,but cv 2 I know was at 0.The buzzing noise changed in increments along with the frequency of the noise like small increases.So I proceed to play with the cv's around that number and did a typo and accidentally changed cv 157 and it changed direction when it started to move. Aparantly cv 130 is like cv 2 ,131 cv 3 and so on. I would not think that it would change 2 3 and 4 to default or it should have just zeroed them out to default if that was the case to my understanding since it was beyond their range . Now I confused myself 
Johnny