Needed - Circuit diagrams for USB model railway controllers

Discussion in 'The Projects Forum' started by grumpymonster, May 15, 2011.

  1. grumpymonster

    Thread Starter New Member

    May 15, 2011
    Hi, I'm wanting to make a USB controller for my model railway. Ideally it should be able to control power to different sections of track, receive inputs for things like train locations, control points and other switchable items i.e. signals, lights etc.

    So far I've found that these functions will probably need to be split over a few different units. I've found some examples of ones that you can buy

    I would really like to build some from scratch using some circuit plans but I haven't been able to find any of these on the Internet, so far. :(

    Is there anyone who knows where I might be able to find these?

    I've also found that these units can be controlled using visual basic. Any help with this will also be much appreciated. :)

    Many thanks
  2. hgmjr

    Retired Moderator

    Jan 28, 2005
    Greetings Grumpymonster,

    Welcome to the forum.

    The project you have described is as interesting as it is ambitious. What experience do you have in the area of computer programming?

    grumpymonster likes this.
  3. grumpymonster

    Thread Starter New Member

    May 15, 2011
    Hi hgmjr and thanks for the welcome.

    I have a fair amount of experience playing with Qbasic which started when playing with the old BBC and Acorn electron computers. What I would be looking for would be examples that I can look at and modify to my liking :) The main problem I have at the moment is finding the circuit diagrams needed. I'll worry more about the programming side a bit later (if you know what I mean?).

  4. SgtWookie


    Jul 17, 2007
    Are your trains DCC ready?

    I'm not sure what you want to do. If you're planning on getting into DCC, you'll really need to do a good bit of research on your own. Various manufacturers have various standards for model railroad control signals; some can be used together on the same layout.

    The idea of DCC is that instead of having analog controls to change the speed of trains, brightness of lamps, etc. that the individual devices all get the same power, and recognize control signals that are sent on the power lines, which helps to minimize wiring. If you go with using individual switches/relays instead, your system will quickly become unwieldy and less than reliable, as you will have a LOT of wiring to install/maintain.

    This site has some helpful stuff:
    Wiring for DCC:
    Performing a Google search for "model train digital control" will give you millions of hits.
  5. kubeek


    Sep 20, 2005
    The basic question is "how large?". There will be a big difference between a 1*2m railway and a 20*30m.
    Then you need to decide how many active elements you need - all the switches, lights and position contacts will need some pins to go to. From this you can decide if you want one large microcontroller that controls everything, or many smaller ones that can control for example 4 switches and few lights + plus one master that controls the rest.

    You could also have just many small micros connected on a bus and control the whole thing from a PC immediately instead of programming the master controller.

    There are many options how it can be done, and you need to start by setting the basic goals.