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JMRI Install Guide: Mac OS X

New Comm Library for Mac OS X

This page describes how to install a new version of the Java communications library for JMRI. This is experimental and we would greatly appreciate your feedback. Currently (Spring 2006), we recommend this for users connecting to Lenz systems (LI100, LI101, etc), for those having certain types of problems with USB to serial adapters, and everybody who has an Intel-powered Mac.

This is unfortunately a long, detailed process. Once we're sure it's actually working, we hope to find somebody to build an installer that does all of this automagically.

  1. If you have installed the old version of the program, you have to remove it manually.
    These steps only undo the actions of installer you used earlier to install these libraries; they should have no other effect on your system.
    To do this, open the Terminal application (from the Utilities folder in the Applications folder) and in the resulting window type the lines (you will probably be prompted for an administrator password):
    sudo rm /System/Library/Frameworks/JavaVM.framework/Home/lib/ext/comm.jar sudo rm /System/Library/Frameworks/JavaVM.framework/Versions/1.3.1/Home/lib/javax.comm.properties sudo rm /usr/lib/java/libSerial.jnilib
    You might get a message about "No such file or directory"; that can be ignored.
  2. Install the new Java serial communications library
    Download the new library archive from http://prdownloads.sourceforge.net/jmri/comm.jar?download.
    You now have to copy it from the directory to which it was downloaded to it's correct location. To do this:
    1. Drag the downloaded comm.jar file to the Desktop so we can find it
    2. Open a Terminal window (see above) and type:
      sudo cp ~/Desktop/comm.jar /Library/Java/Extensions/
  3. Install the new RXTX libraries.
    Download the new library archive from http://prdownloads.sourceforge.net/jmri/RXTX_Jag_4.pkg.sit.hqx?download.
    Unpack and run that installer. It might mention various things that you have to check about the "uucp group" and similar. You can just ignore those, as they're being handled by the installer and the previous steps.
    When the installer is complete, restart your computer.

At this point, you should be able to start any of the JMRI applications (or other Java programs) and communicate via serial ports.