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Release Notes for JMRI 4.21.4 release

Date: January 29, 2021

From: Bob Jacobsen

Subject: Test Release 4.21.4 of JMRI/DecoderPro is available for download.

Notes:

This is a test release. Please post a note if you encounter any new or old bugs! And please back up your JMRI files before installing this, in case you want to go back to an earlier version.

This is the next in a series of test releases. We expect this series to end in the next JMRI production release in early 2021. (See the tentative release schedule)

Some of the changes involved are quite extensive. They may require a certain amount of experience before they are working well. Therefore, this test release should be considered experimental.

JMRI is now only available under the GNU General Public License. For more information, please see our copyright and licensing page.

Update From Older JMRI Versions

If you are currently using a version older than JMRI 4.20, please follow these instructions carefully:
  1. Is your current version older than JMRI 4.12? If so, then update to JMRI 4.12 first, and ensure everything works correctly: check start-up, check things you need to be working, and check the JMRI log as well) before doing anything else. Store your configuration and panel files under a new name and use those from now on. Then continue with step 2.

    If you are currently using JMRI 4.7.3 or earlier on Linux or macOS (Windows doesn't need this), then it's very important that you update to JMRI 4.12 and carrying out the migration process described in the JMRI 4.12 release note before updating to any later relese.

  2. Is your current version older than JMRI 4.20? Then update to JMRI 4.20 first, and ensure that works correctly (check start-up, check things you need to be working, and check the JMRI log as well) before doing anything else Store your configuration and panel files under a new name and use those from now on.
  3. You can then install this release.
Following this multi-step order of updating via stable major releases safeguards you against possible migration issues that can arise from skipping these versions.

New problems with this release

New warnings for this release:

Older warnings

See the JMRI 4.20 release note for more warnings predating the 4.21 development series, including pointers to various migration issues. These may be relevant to you if you're updating from an earlier version; we strongly recommend you update to JMRI 4.20 installing this test release.

Download links:

Please note that the download links in this and future JMRI releases link to Github servers. People are welcome to distribute the download files further via other websites, etc. If you want to check that you've received original, unmodified versions, please check the files against the checksums shown below.

Changes since Test Release 4.21.3:

The list of included changes is available from our GitHub code repository.

Hardware Support

DCC-EX

LocoNet

Uhlenbrock Intellibox

New / Updated decoder definitions

Digikeijs (Digirails)

Digitrax

Uhlenbrock

Dispatcher System

Meters and MeterFrames

Operations

Preferences

Signals

Cab Signals

Switchboard Editor

Timetable

Warrants

Miscellaneous