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JMRI: DecoderPro User Guide

Updating Decoder Definitions

New and updated decoder definitions are occasionally created. The best way to get them is to update your copy of JMRI to the most recent test release. If you don't want to wait for a monthly test release, you can also pick up a development release. Development releases are available within a day of the new decoder definition being merged into JMRI.

Sometimes, a user will put a new/updated definition in the files area of JMRI users (log in to access).

To use these xml files you need to download and install them.

The installation process was simplified in JMRI 2.3.6, where "Import Decoder File" and "Import Decoder URL" menu items were added to the Debug menu (in PanelPro or "legacy" DecoderPro) and to the File menu (in DecoderPro "Roster view").

Note that this download and install process only works for the main decoder definition file. Some decoder definitions include small subsidiary files from subdirectories. Updates to these are best obtained via a test or development release to ensure consistency.

JMRI v 2.3.6 and later

This section describes adding a new decoder definition when you are using JMRI version 2.3.6 or later.

Loading a definition from the web

If you have a URL for a decoder definition, perhaps copied from a web page or email, and your computer has an active Internet connection, you can directly install the definition. Unless there are errors, the file will be copied onto your local computer and installed in your JMRI Preferences directory.
Learn about JMRI Configuration Files

Loading a definition from a file

If you have local file containing a decoder definition, perhaps downloaded from a web page or received via email, you can install that definition in JMRI. Unless there are errors, the file will be copied into your JMRI Preferences directory and installed.

How This Works

Both of these tools take the decoder definition information from the source you indicate and copy it to your local JMRI Preferences directory so that it will be available from now on. For this to work, you can't already have a decoder definition file there by the same name. If such a file does exist, the program will indicate an error and not replace the file.

The definition is stored in your Preferences directory, instead of the JMRI distribution directory, so that installing a new version of JMRI doesn't delete it. Note, however, that if a newer version of JMRI comes along with a copy of this decoder definition installed, the program will give priority to the specific version that you imported. JMRI thinks you knew what you were doing when you specifically imported that specific version. If you'd prefer to use the one in the new JMRI version, you should delete yours from your Preferences directory and select "Rebuild Decoder Index" in the debug menu.

JMRI v 2.3.5 and earlier

This section describes adding a new decoder definition when you are using JMRI version 2.3.5 or before.

On Windows Systems

On Mac OS X Systems