I went to us my JMRI program the other day and ran into problems. I could not get decoder pro to stay in service mode. could not find USB PORT.
OK tried several times. Figured I needed to update. Did that and upgraded JAVA to.
Now when I try to open decoder-pro, I get a Java error. A java exception has occurred. Says to make sure older versions of Jave have been removed and do restart before install a new version. I have done that more than once and get the same error. the more I read the less I know.
I see in the JMRI forum this has happened in the past.
any help with this? thanks in advance.
Hi there,
I think you have a couple of things going on here:
1. There was initially a communication problem from JMRI/DecoderPro to your USB device that is providing a serial interface to your DCC system or standalone programmer. This is quite common and the a lot of different reasons that this can occur. USB/COM ports can suffer issues where their device addressing changes, or a different program (or crashed instance of JMRI) won't let go of the port. Or it could be that there is a problem with the device connected to the USB port (cable, power, configuration issue).
Generally it's best to troubleshoot starting with the simplest steps and changing as few variables as possible — i.e. not changing the software versions or applying updates except as a last resort. I'd start by rebooting everything (shutdown the computer, power cycle the USB interface / Command station). Check cables. Power everything up and check for lights. Take a look at whether JMRI can see the interface again via USB or whether the COM port or serial address has changed in the JMRI Preferences Connection and build out from there. (Apologies if you already tried all these steps).
2. The Java exception is something I've run into quite a lot on both Mac and Windows. This will likely be an incompatibility between your JMRI version and the Java version after you changed this.
If you have not done so already, I would take a backup of your JMRI folder(s) and make sure you don't lose any roster entries, panels, or preferences when re-installing.
I would uninstall Java completely, and re-install a Java 11 version that is known to be compatible with the current JRMI 5.4 stable release.
The instructions for this are listed here:
https://www.jmri.org/java/index.shtmlI've had great success with the Zulu 11.x releases recommended by JMRI. (I've not had any success with the later Oracle releases).
Once you have Java re-installed, there is an Install Test script in the JMRI folder that you can use to interactively test the Java install and then launch JMRI step-by-step. At the very least, if you run into issues, you will have some logs and clues as to where the issue is.
If Java looks good, but JMRI still fails, then you can move your current JMRI folder aside, and install the latest JMRI stable release. Once you can get back to a functioning JMRI / Decoder Pro, you can then go back to troubleshooting the original issue.
Hope that this helps
Cheers.
