Other Apps


JMRI provides powerful tools for working with your layout.

Layout Automation

JMRI can be used to automate parts of your layout, from simply controlling a crossing gate to running trains in the background.

JMRI: DecoderPro User Guide

Current as for JMRI version 4.2

Introduction to the JMRI Symbolic Programmer

Modern DCC decoders are complicated beasts to program. The simple idea of "put the address in CV01" doesn't cope well when you program complicated functions using combinations of bit patterns. A friendlier interface is needed. There are programs that provide better ways of programming specific decoders. Unfortunately, they are limited to specific types of computers, and only their authors can customize them for new types of decoders.

The DecoderPro symbolic programmer is meant to improve this. It is configured using text files, so that it can be adapted to additional decoder types easily. It talks to the decoders using the JMRI programming interface, so that it can run on any computer and layout hardware that JMRI has been ported to. It's freely available for download. And since the code is available via open source on GitHub, if you want to improve on it you can.

The Quick Tour introduces how DecoderPro looks and how you may use it.

DecoderPro is also covered in Joe Fugate's TrainMasters.TV video library, part 3.4, as he shows how he used DP on his Siskiyou Line layout.

What you need to use DecoderPro

DecoderPro will work on Windows, Linux, Macintosh (MacOS 8.6 through 9.2 and OS X). It will probably also work on most other modern operating systems that have Java available; contact us for help if you'd like to try it on some other system. You need to have a serial port or USB port available, either on the computer itself, or via a USB adapter. For more information, please see the Setup pages.

You also need to have a connection to your DCC system. For more information, please see the DCC hardware pages.

DecoderPro User Guide

Working with the Roster
How DecoderPro Works
Configuration Files
Frequently Asked DecoderPro Questions

Refer to the DecoderPro Manual for more information on how to use DecoderPro.

Advanced Guide

Intro to XML files
Create your own decoder definition
Create a custom programmer definition
How the Roster is stored; updating it by hand
Locomotive (Roster) files
Sharing Rosters among Computers
Updating Decoder Definitions

Decoder information

The JMRI project has compiled a lot of information about decoders from many manufacturers, which we make freely available in several forms. To learn more, see the Decoder information page.