The JMRI Manual
Installing JMRI
Using DecoderPro®
DecoderPro® Programming Modes
The Basic Programmer
The Comprehensive Programmer
DecoderPro® Main Window
Creating a Decoder Definition
Error Messages

JMRI® v2.12 Manual (Archived)

Last updated 1/9/2012

JMRI is a Java-based cross-platform application for model railroaders. JMRi contains applications for:

The programming of Digital Command Control (DCC) decoders, (DecoderPro®).
Drawing computer based panels for depicting a model railroad  layout , (PanelPro® ).
Controlling the layout , (Layout Editor).
Creating train manifests for duplicating railroad operations, Operations
Controlling the signals on the layout
Controlling  lighting and sound in the room, and so forth. (SoundPro®)

All this capability is contained in one program (JMRI) which has several “start-up” screens for the various applications.

 JMRI® can run on any computer system that will run Java 1.5.0 or later, whether it is Macintosh, Windows, or Linux based. It does require that Java be installed on the computer. You can get Java as a free (but very large...) download at:

If this is your first visit to our manual we suggest that take the DecoderPro® tour to get an overview of what we're about to cover.

Note: All screen shots in this manual are from a Windows machine using the "Metal" User Interface option . While your screens will probably differ in some layout details, they will be essentially the same. All programming examples shown are with Digitrax PR3(MS100 mode) connected to Digitrax Super Chief Radio Command Station. Most of the decoders in locomotive samples will be Digitrax, except for sound examples.

Note: This entire manual has been updated to correspond to DecoderPro 2.12, and the HTML verified using HTML4 and Cascading Style Sheets. If the formatting looks odd, you probably need to update your browser.

Table of Contents

Installing JMRI

Getting started

Using DecoderPro®

DecoderPro® Programming Modes

The Basic Programmer

The Comprehensive Programmer

The Advanced Programmer

DecoderPro® Main Window

JMRI® Operations Program

Creating a Decoder Definition

Error Messages

To give feedback on this HTML manual, ask questions about things not covered, or make suggestions for improvements to the manual or the software, join us on the JMRI users group.

Thanks for reading, and Let's Run Trains!

Version Revision Date Editors Major Revisions
original 9/4/2002 Joe Ellis Bethlehem-Ares Railroad, a 1:160 Corporation
1.3 no date Bob Blackwell Updated to JMRI version 1.3
2.4 2/15/2009 Dale A. Tripp Bruce Shanks Updated to JMRI 2.4, new sections added
added Main Menu information
added Decoder Definition How to
added Error code page
2.8 1/15/2010 Dale A. Tripp Bruce Shanks Updated to JMRI 2.8
Expanded Table of Contents with additiona direct links
Updated Comprehensive Programmer, moved Function Label pane to Advanced Programmer
added Advanced Programmer features, including Roster Media pane
Added Roster Group feature
Updated decoder definition submission process
Added Operations section
2.12 9/15/2011 Dale A. Tripp
Bruce Shanks
Walter Thompson

Updated to JMRI 2.12
Installation information added
Contents updated to current functions