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DCC

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  • Member since
    October 2008
  • From: Omaha
  • 25 posts
DCC
Posted by atsfandy on Friday, October 31, 2008 8:36 PM

Hello,

 I am a relatively new user of the Prodigy Advance, I have learned enough to program the correct address to the locomotive and how to set some CV's to allow me to turn on the headlight and rearlight independently no matter the direction of the locomotive,  I currently am using Digitrax decoders on most of my loco's, what I would like to know is what are the CV's that control the dimming of the headlights both front and back and what is the correct value or variable that I use make this happen?  If someone can help I would really be in heaven.

 

Tags: DCC
  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Friday, October 31, 2008 9:29 PM

Step 1: For the Digitrax decders, downlaod the Digitrax Decoder Manual: http://www.digitrax.com/ftp/decodermanual.pdf

 Step 2: Start on Page 39, that's where it starts talking about the CVs that control the function outputs.

 Now you need to figue out just what you want to do. You said you configured the lights to operate independently. It sounds liek what you want to do is have an F button turn the front light on and off, regardless of direction, another function to dim the front light, regardless of direction, another function to turn the rear light on and off regardless of direction, and a fourth function to dim the rear light, regardless of direction. I don't think you can do this, it would have 2 functions controlling the same output and if one says "on" and the other says "dim" it's going to be on. The standard way of doing this is to apply what's called "Rule 17" since that's the rule number in real railroad rulebooks covering the headlight brightness. Most decoder brands do this, certainly Digitrax ones do. This setting dims the light when moving in the opposite direction OR when you press a function key. The default is F4. So if you are moving forward and the headlight is on, pressing F4 would dim it. Or if you are moving forward with the headlight on, stop, and start moving in reverse - the headlight dims. You can't take the direction qualifier off the Rule 17 dimming option. I'm pretty sure I've tried using a value of 40 in CV49 instead of the usual value of 68 for Rule 17, and it didn't work. You can try it. If it works at all it would be 40 in CV49, 40 in CV50, and then 0 in CV34 and 2 in CV35 (F0 for headlight, F1 for rear light - if you've already changes these to something else you can leave it alone and use what you have). My guess is it won't dim the lights when you press F4 with those settings. The values for dimming lights are normally CV49 = 104 and CV50 = 120. The 104 and 120 make it directional but if you look in the manual you'll see these values are specfically called out as 'special logic for Rule 17". Actually, the manual shows hex number but if you have Windows just open the calcualtor and change the view to Scientific and there is a handy hex calculator for you. Enter 104 with Decimal selected and then select Hex and you will see this is 68. 6 as the first digit in the table says "special logic for forward ditch light or Rule 17 dimming". 8 as the second digit says "Rule 17 dimming"

                     --Randy

 Edit: even withotu a computer itnerface, you can use JMRI Decoder Pro to help figure out what CV values to program. When you runt he program you need to pick a layout conenction, use Loconet Simulator and set the programmer to 'comprehensive'. The open the programmer under the Tools menu, use the Service Mode programmer. In the large list in the middle, pick your decoder model and click "open programmer" Go to the Lights tab and pick your settings, then go to the CVs page. Scroll through the list - any of them highlighted in orange are ones that need to be changed. Program whatever CV needs to be edited with the value shown. Very handy.

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    January 2001
  • From: SE Minnesota
  • 6,847 posts
Posted by jrbernier on Friday, October 31, 2008 9:33 PM

  You will need to look at the Digitrax lighting effects area of the decoder manual for your decoder to see what you can change.  Go to the Digitrax web site and click on 'manuals & instructions'  Look at the manual for your decoder manual and the mobile decoder manual for complete information.  Here is the URL for the mobile decoder manual:

http://www.digitrax.com/v1/ftp/Decoder%20Manual.pdf

Jim

Modeling BNSF  and Milwaukee Road in SW Wisconsin

  • Member since
    October 2008
  • From: Omaha
  • 25 posts
Posted by atsfandy on Friday, October 31, 2008 10:15 PM

 Randy thank you sir I will follow wha you said and see where it leads. 

 

Thanks again Andy

  • Member since
    October 2008
  • From: Omaha
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Posted by atsfandy on Friday, October 31, 2008 10:20 PM

 Jim thank you as well.  I will have to say that I am not very good with reading when it comes to these manuals.  I don't quite understand some of the things that they say any way I am very appreciative your help

 

  • Member since
    May 2007
  • From: Auckland, New Zealand
  • 147 posts
Posted by Steve_F on Friday, October 31, 2008 11:56 PM

I gave up trying to get my locos with Digitrax decoders to dim manually, NCE & TCS decoders have the option of manual control which has endeared them to my favorite decoder brands, in saying that two of my best running Locos (P2K GP7’s) have Digitrax decoders (DH-165LO), just can’t figure out how to dim the lights manually.

I too would be interested if any one has figured out how to do this. Sigh

 

  • Member since
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  • From: Omaha
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Posted by atsfandy on Saturday, November 1, 2008 10:09 AM

 Randy I gave it a try and I did see the result that you were speaking of I guess I am really looking for the whole independent control aspect of DCC so I may have to try another type of decoder or just live with what I have and be happy.

 

Thanks again for your advice look forward to seeking advice from you again.

 

As well as Thanks to everyone who tried to help I am very appreciative of that

 

ANDY

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Saturday, November 1, 2008 12:07 PM

Steve_F

I gave up trying to get my locos with Digitrax decoders to dim manually, NCE & TCS decoders have the option of manual control which has endeared them to my favorite decoder brands, in saying that two of my best running Locos (P2K GP7’s) have Digitrax decoders (DH-165LO), just can’t figure out how to dim the lights manually.

I too would be interested if any one has figured out how to do this. Sigh

 

 Just put 104 on CV49 and 120 in CV50. The headlight will be on if F0 is turned on and you are going forward. It will be dim when going in reverse, or at any time you turn on F4. Same with the rear light. If you don't want the rear light to dim, just be on or off, set CV50 to 0 or 16. That one might be confusing - the example shows 00 for no effect but 00 would be on in forward direction, x10 (hex) would be on in reverse direction, which equals 16 decimal. I think 16 would give you rear light on when moving in reverse with F0 on, and the rear light off when moving forward with F0 on. Try both. I don't have my old files from DecoderPro to see what I had in my GP7's with DH163L0 decoders. But that's the way I had mine set up - Rule 17 dimming on the front light and normal directional operation on the rear light.

                             --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    October 2008
  • From: Omaha
  • 25 posts
Posted by atsfandy on Saturday, November 1, 2008 1:28 PM

 thank you sir I appreciate it

 

ANDY

 

  • Member since
    May 2007
  • From: Auckland, New Zealand
  • 147 posts
Posted by Steve_F on Saturday, November 1, 2008 6:18 PM
Thanks Randy that works as you say, (CV 49 = 104, CV50 = 0) I didn’t want the lights to dim when changing direction but guess I will have to live with it in this case. The two GP7s will run in consist back to back so I wont be using their rear lights therefore rear dimming wont be required any way.
  • Member since
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  • From: Mpls/St.Paul
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Posted by wjstix on Monday, November 3, 2008 4:32 PM

I like to set engines up that way because it allows you to keep the headlights on, yet confirm which direction you're going to go since the light in that direction is brighter. BTW real engines don't use reversing headlights like our models (light on in direction of travel only) but they were usually set up so the headlight could be on full, on dimmed, or off. For example, when meeting another train, a train stopped on a sidetrack would dim it's headlight. You can simulate that by stopping the train and reversing direction without putting any power to the train (well at least with some systems you can) so the light is dimmed.

Stix
  • Member since
    July 2006
  • 3,312 posts
Posted by locoi1sa on Monday, November 3, 2008 5:02 PM

 The TCS decoders have dimmed when stopped feature. They also have CV settings for dimming an LED or bulb.(Dimmed brightness) Also can be dimmed with a function press. I usually set mine up with dimmed when stopped and dim on F4. My switchers are set up with opposite light dimmed. Except the switchers that are run in pairs. 

     Pete

 I pray every day I break even, Cause I can really use the money!

 I started with nothing and still have most of it left!

  • Member since
    February 2007
  • From: Warren, MI O scaler
  • 553 posts
Posted by el-capitan on Tuesday, November 4, 2008 2:57 PM

wjstix

BTW real engines don't use reversing headlights like our models (light on in direction of travel only)

This is typically true when the engine is connected to a train. However, whenever I have seen engines running light (without cars) they usually have front on bright and rear on dim.

 Check out the Deming Sub by clicking on the pics:

Deming Sub Deming Sub

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