DCC++ experimentation

Discussion in 'Techniques' started by 76043, 4 November 2019.

  1. 76043

    76043 Western Thunderer

    Having had an Arduino Uno kicking around for some time doing nothing, I read up on DCC++

    DCC Plus Plus - DCCWiki

    It uses the Uno and a motor shield, so I bought the motor shield.

    It interfaces with JMRI which can use the DigiTrainsPro android app, so just wondered if anyone has gone down a similar route to this before? I'm pretty savvy with sorting out all this stuff and don't wish to spend hundreds on a bells and whistle (ha ha!) system.

    I'm interested in this for a 7mm Dapol 08 powered shunting plank, so the ability to expand is not necessary. I would have just used DC for this, but do like the idea of the possibility of lights and sound on the 08.

    So far all in costs are less than £50 which suits me.

    I tried searching on DCC++ but the forum software says my search keywords were too short, too long, or too common.

  2. Yorkshire Dave

    Yorkshire Dave Western Thunderer

  3. simond

    simond Western Thunderer


    Thanks for that rabbit-hole, very interesting project. I’m trying to do other stuff with Arduinos at present, or I’d get lost down there for years!

    Please do post your progress
  4. 76043

    76043 Western Thunderer

  5. 76043

    76043 Western Thunderer

    I will, I have all the parts now, including a Zimo non-sound decoder for the 08. Was only £20 so worth it for testing purposes.

    Could be interesting if I can get it to work with my phone.
  6. 76043

    76043 Western Thunderer

    I finally found my Arduino UNO so let the experiment begin!

    Last edited: 8 December 2019
    michl080, adrian and ChrisBr like this.
  7. adrian

    adrian Flying Squad

    I shall be watching with interest. What current does the motor shield drive and does it need a separate power supply?
  8. 76043

    76043 Western Thunderer

    Adrian, I have built the base station as per the pic below and have got JMRI supposedly talking to it. I had some spare 12v DC transformers knocking around, but it seems the motor shield requires 15-18v, so will look around for something suitable.

    Seems like 12v isn't entirely suitable not for loco power but for the system itself, according to this forum. The ampage recommended seems to be 1000ma.

    12V supply OK for DCC HO scale? | Model Railroad Hobbyist magazine


    adrian likes this.
  9. michl080

    michl080 Western Thunderer


    that is quite surprising. The Arduino should run fine with 5V from the USB port. The schematics of the motor shield as well as the schematics of the Arduino itself warn to use supply voltage above 12V.
    What happens if you supply the boards with 12V?

  10. 76043

    76043 Western Thunderer

    There's a jumper on the motor shield that requires cutting in order to stop the motor shield powering the Arduino. The motor shield can take up to 18v, but over 12v will fry the Arduino, so this is why they recommend cutting the jumper.

    The Arduino itself is then powered by the USB cable from the computer.
    michl080 likes this.
  11. 76043

    76043 Western Thunderer

    Well, I thought I'd measure the voltage from my trusty Gaugemaster model E and it surprised me by going up to 14v.

    So I thought ok, let's see what happens when you connect it all up as per this photo.


    So Mac on the left with JMRI loaded, connected to Arduino. The Gaugemaster is connected to the motor shield, which is then connected to the loco. I had no idea what the +/- outputs are on the Gaugemaster, but worked it out with the multimeter.

    Then amazingly it all worked! I tried reading the decoder, which identified two Zimo variants, so selected the right one. One of the loco lights flashes as it reads the chip, so I was confident it was working. I created a loco roster then rewired the motor shield from the programming track to the main track.

    I opened up the throttle page and the loco's wheels actually moved on my rolling road! To prove this is working I turned the light on in the photo.

    I'm amazed I got this up and running in a couple of hours all for £45 for the base station and £20 for the Zimo decoder. It's my first ever experience with DCC so I'm very happy especially at the price.

    Next stop to understand all the functions and acceleration controls, then possibly using my phone as a controller or a Raspberry Pi instead of my Mac.

    simond, adrian, Ian_C and 2 others like this.
  12. 76043

    76043 Western Thunderer

    I couldn't resist connecting up some track and was very, very impressed with the slow speed running. The loco has a flywheel, but the decoder is a feedback type, so both these must contribute.

    Seeing all the lights working was fun too.

  13. iain_r

    iain_r Member

    DigiTrainsPro did nothing but crash on my Samsung Note 9 but it just applied a system update about 30 minutes ago. I'll give it another try.
    I've not experienced an Arduino before but as someone with a stack of Raspberry PIs at home, I think I should..
    76043 likes this.