Basic DCC Decoder Question

Xrayvizhen Jan 12, 2021

  1. Xrayvizhen

    Xrayvizhen TrainBoard Member

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    Here’s another basic noob question that I suppose, if I put the correct combination of words into a Google search I could find the answer to, but I figured I’ll just ask here: Are the DCC sound/light functions the same on all locomotives or do I have to keep sheets of instructions for each loco I buy and refer to each one for the different functions? (Or does it change by manufacturer?)

    So I made my first DCC locomotive purchase, a Bachmann EMD-SD45. It was cheap and I just needed something to test out my NCC PowerCab Starter Set and after a few jittery fits and starts and after running it for a few hours now it’s actually working pretty OK.

    For the basics I don’t have to remember anything because the PowerCab has specific buttons for horn, bell and lights but according to the instruction sheet that came with the engine there are a few others; F2-Airhorn, F3-Short Airhorn, F7-Dimmer and F8-Mute. Also, F4-Airbrake is supposedly not available for the SD45 yet when I press F4 there is some sort of change in the motor sound and the loco comes to a fairly quick stop. So are these functions the same for other diesel locomotives, will I have to save the little instruction sheets for each and every one I buy or will they all be the same? Also, is there a way to use the PowerCab screen to see what different functions might be available for any particular loco I eventually get?
     
  2. DMiller-1960

    DMiller-1960 TrainBoard Member

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    Xrayvizhen

    I can't answer your questions.........but I certainly am looking forward to the others responses! I am just making the change from DC to DCC on
    our little layout, and have lots of questions, too. I have been doing a fair amount of reading, but also look for others experiences. I am just waiting for my Digitrax system to arrive so I can start the hands on learning process! Good luck with your endeavors.

    Darryl
     
  3. RBrodzinsky

    RBrodzinsky N scale Staff Member TrainBoard Supporter

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    There are certain functions which are "standard" (note: can still be remapped in many decoders) while others are decoder manufacturer specific, especially as you get into sound decoders. But, most of today's modern decoders allow the user to remap the functions, so that you can always put same/similar actions onto the same function buttons. Front/Rear Headlights(F0), Bell (F1), Horn (F2) are really the main "always in this position" functions

    But, and this is very important, don't try to do this with simple throttle based programming. You really need to hook up an interface for JMRI DecoderPro to your DCC system, so that you do not have to rely on knowing which registers to change on your own (and with sound decoders, there can be thousands of registers in a decoder). The JMRI community has a number of folks who have written complete interfaces for almost every decoder available, and the functions are presented in plain English (i.e. you don't have to know that CV2 is minimum speed, CV3 is acceleration, etc.).

    Especially with starting off with only one or a couple of locos, but planning to expand, spend some time with DecoderPro now. Figure out where you want the functions (i.e., you may not want the dimmer on F7), and learn how to adjust.
     
  4. crusader27529

    crusader27529 TrainBoard Member

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    Besides what was already said, JMRI can, when used with Engine Driver SW on a smart phone as a throttle, allows you to label each function button, so you don't have to remember what each loco has assigned to each function.
     
  5. RBrodzinsky

    RBrodzinsky N scale Staff Member TrainBoard Supporter

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    Very true, but I didn’t want to overwhelm DCC newbies with too much all at once. ;)
     
  6. Xrayvizhen

    Xrayvizhen TrainBoard Member

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    So....it looks like I will have to buy another gizmo, a USB computer interface, which for the NCE PowerCab, appears to be this? (Another 50 bucks - Crap!). And I really didn't want to be dealing with a computer for this. So what I think I'm gonna do is wait until I get locomotive #2. Sooner or later that will happen but since the PowerCab has dedicated buttons for the basic horn, bell and light functions, I'm OK for now. I was just wondering if there was commonality between locomotives from different companies.
     
    Last edited: Jan 14, 2021
  7. BigJake

    BigJake TrainBoard Member

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    Decoder Pro (the decoder programmer app, in the JMRI suite of applications) was a big reason for me to recently make the jump from DC to DCC. I'm still "jumping," but oh, the places I'm jumping to!

    However, please note that virtually everything that Decoder Pro does can be done manually using the decoder manual/datasheet, your Power Cab, a pencil and paper. The computer and JMRI (and the USB interface) make it much easier, but at it's own "cost" of complexity, equipment and knowledge.

    As for the costs associated with DCC (or any other aspect of any other hobby), we all have to live within our budgets (eventually), so plan accordingly. Plan your purchases so they give you the best bang for the buck in the long run.
     
    bigGG1fan likes this.
  8. S t e f a n

    S t e f a n TrainBoard Member

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    So, I went through the same calculation as Xray (another 50 bucks just to hook up the NCE Power Cab to a computer???), and bought an arduino plus motorshield. It's just a smidgen cheaper than the NCE USB interface, but I'm hoping I can additionally use it for some automation.
    Just my 2 cents.

    If we could find somebody smart, they could reverse-engineer the NCE protocol, and tell us how to hook up an Arduino as the computer interface. Well, if they were really smart, they would figure it out and then sell it to us. So, we need somebody smart, but not too smart.
     
  9. Xrayvizhen

    Xrayvizhen TrainBoard Member

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    Yep - at this point I'd rather spend the 50 bucks on some rolling stock or whatever artsy stuff I'm going to need for the scenery, buildings, etc. I'll use pencil and paper RAM, if needed.
     
  10. Xrayvizhen

    Xrayvizhen TrainBoard Member

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    So, the learning is continuing while the layout construction is going on but here's a question about a weird problem I just experienced that may be specific to the NCE PowerCab, or the two Bachmann locos I bought or maybe it's simply has to do with my reluctance to read manuals.

    I've been playing with the SD45 I bought a few weeks ago, doing no programming, keeping it assigned to Address 3, as it came from the factory and there have been zero problems at all.

    Then I just picked up a Bachmann K4 Pacific, on sale from Trainworld. It too programmed to Address 3. I removed the SD45 from the track and began to break in the K4. A few jitters and some stuttering, but it got an excellent Spookshow rating so no concerns figuring things will eventually smooth out. It was working fine...all functions responding. But then I decided to get cute and change the address of the K4 to short address #2. I figured I only have 2 engines so I'd make the SD45 #1 and the K4 #2. It would keep things simple and besides, the numbers on the cabs are so tiny they're hard to read.

    Here's where the problem started. The K4 wouldn't accept the short address! I tried several times and even resorted to going through the manual step by step and it still wouldn't take. I was actually getting ready to call NCE when I thought as a last resort I'd try to program the long address, using the Cab# and YES...that worked! At that point I decided to play it safe for now and keep the SD45 to Addr. 3 until I can figure out what I'm doing wrong.

    So is it "Operator Error" and if so does anyone have any idea what I did wrong or is it something peculiar to Bachmann locos, or could it be something else entirely?
     
    Last edited: Jan 21, 2021
  11. Xrayvizhen

    Xrayvizhen TrainBoard Member

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    ....OR
    Can you only program short addresses on a programming track? (I don't have one.)
     
  12. BigJake

    BigJake TrainBoard Member

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    The Power Cab has only one set of track outputs. When in programming mode, the attached track, even if it is the entire layout, is the the programming track.
     
  13. RBrodzinsky

    RBrodzinsky N scale Staff Member TrainBoard Supporter

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    I always change addresses in Program Track mode, never PoM
     
  14. Xrayvizhen

    Xrayvizhen TrainBoard Member

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    I tried that and got a message, "cannot read CV" yet in "program on main" mode was able to program the cab number.

    With only 2 engines I'm ok because I just use the "recall" button to toggle between the two. I was just wondering what I was doing wrong.
     
  15. BigJake

    BigJake TrainBoard Member

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    I think you may have something drawing current on your layout that prevents the programming track mode from being able to read back the programmed locomotive's registers. Do you have any stationary accessory decoders (for turnout control or signals) that are run from the track DCC bus?
     
  16. Xrayvizhen

    Xrayvizhen TrainBoard Member

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    Nope. There's a buss for the track and a separate one for the turnouts.
     
  17. sidney

    sidney TrainBoard Member

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    get jmri and a dedicated computer for trains. something cheap but works great. you wont be disappointed and its well worth it from the start.
     
  18. BigJake

    BigJake TrainBoard Member

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    But is the turnout control bus also tied to your Power Cab?

    If so, they may be drawing too much current for the readback to work when using the normal programming mode (not POM). If you can add a switch to disconnect that bus while programming, that may solve your problem...
     
  19. BigJake

    BigJake TrainBoard Member

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    I agree heartily about JMRI, but you don't necessarily need a dedicated computer for it. Sure, a dedicated computer is nice, but is not mandatory.

    You will need an NCE USB Interface for your Power Cab though. The computer running JMRI controls your Power Cab through that interface.

    JMRI Decoder Pro will rock your world when it comes to programming decoders, compared to your Power Cab's keypad!
     
  20. Xrayvizhen

    Xrayvizhen TrainBoard Member

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    Nope. They're totally separate. I can disconnect the Power can from the layout entirely and the turnout switches will still throw in both directions. (They're connected to DPDT toggles). Later today I'll try to program the other loco and see what happens. Maybe it's a thing with that particular loco but I still suspect I'm doing something wrong.
     
    Last edited: Jan 24, 2021

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