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Hardware Support: Oak Tree Systems Railroad Control Interface (RCI)

Supported Hardware

Computer Interfaces


The JMRI libraries have built-in support for Oak Tree Systems serial hardware using the "RSC" bus protocol. inputs can be used as sensors, and outputs can be driven as turnouts.

At this time, the RSI serial bus protocol for the HH-2 throttle is not yet supported.



  1. Start the program (usually PanelPro)
  2. From the Edit menu, select Preferences and configure the Connections tab:
    • System Manufacturer: "Oak Tree Systems"
    • System Connection: For serial port, select the one your hardware is attached to.
    • Select the baud rate configured into your boards
    • Click the "Configure nodes" button. On the new panel that opens:
      • Enter a node address (0 is typically used for the first card)
      • Select the board type from the initialization box
      • Click "Add Node"
      • Click "Done"
    • Back on the "Preferences..." panel, click "Save", and say yes when it asks if you want to quit.
    • Restart the program. Your board's LEDs should now be flashing, indicating that the computer and board are talking.
    • To check that everything is working, select "Turnout Control" from the tools menu. This will open a small window in which you can select a turnout number (see below), then click closed/thrown to change the state of that output.
Use with multiple boards

If you have multiple boards connected to the Oak Tree Systems serial bus, just go back to the "Configure Nodes" window and enter them individually. Don't forget to save the preferences and restart the program.


Oak Tree system names start with "O". For example, "OS24" is a "S"ensor, the 24th input line on the Oak Tree Systems card with board address zero.

Inputs and outputs are numbered sequentially from 1, without worrying about the types of cards, etc.

Each board is called a "node". Sensors and turnouts on the first node are numbered from 1 to 999; sensors and turnouts on the second node are numbered 1001 to 1999; etc.

For example:

  • Say you have a IO-48 with it's address switches set to "2". All of the inputs and outputs on that node will be numbered starting with 2001.
    • CT2001 is the first output pin
    • CT2048 is the last output pin
    • CS2001 is the first input pin
    • CS2012 is the last input pin.

To summarize, input and output pins are labelled sequentially within each node. The numbers go up by 1000 from node to node. Node numbers can go as high as the hardware allows.


Third Party info

For more information on Oak Tree Systems hardware, please see their website.