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Hello all. My name is Mike and I am finally getting into building my layout after a long haitus of collecting. First wife wasn't too supportive of me building a layout in a corner or taking over wall space from hanging family photos. Anyhoo.... in the middle of building a 12 by 13 shelf layout 2 feet deep on top of shelving units in my basement. Still trying to work on a layout design a little more than a regular loop and a couple industries. I had originally thought 4 different switching puzzles on each side of the square but realized it would be too ridiculous. Trying to keep it realistic but i also want to try and stretch my limits. Doing this all myself, dont have any friends to talk with or help me out.
That being said, I tried to install JMRI after reading some good stuff about it but for some reason after I launch the program and tell it I am using a Digitrax Loconet PR4, it wont connect and I am not able to move any further. I am not sure where I messed up or if I am missing something. Any help would be appreciated.
JMRI might not be connecting due to a couple things. Have you gone into preferences within JMRI and selected the "COM" port for the PR4? You can find which COM port is being used (assuming that you are a Window User) by right clicking other start menu and clicking "Device manager". Within Device Manager it will be under "Ports (COM & LPT)." If the PR4 is not showing up in Device manager, the drivers are likely not installed for the PR4. Installing drivers can be a bit of a trick for some devices since Windows doesn't like unsigned drivers.
This is usually the hang up when trying to use JMRI.
I believe you can force Windows to accept unsigned drivers in a preference menu, but darned if I can remember how to get to it. I haven't needed that menu in a long while. Might be under, or along with, internet options.
ok so when i downloaded the drivers and installed it, it only installed sound loader 4.0. when i try to open the JMRI app, it says i need to fix it after selecting digitrax.
Sorry to get back to you so late. That's a new one to me. I would suggest uninstalling both Java and JMRI as a first step and reinstalling both.
Make sure you have right installer for JMRI. It looks like you may have a versions for something like a raspberry pi (arm processor) v. a laptop (AMD or intel processor).
I had the same issue, just got JMRI working over the weekend. The java error says it tried to load an ARM64 on an AMD64 system. I think the ARM64 is Mac.
I looked up that error and apparently there is a problem with the JMRI libraries or something. I left my JAVA install alone, uninstalled JMRI and installed the 5.15 test release. I'm working from memory, but I ran the JMRI install test in the JMRI app group and my java install passed but the JMRI install did not. Then I looked up the Java error as you had posted above. If you look up the java error arm64 and amd64 it will tell you of a problem with the install thinking it's arm64 when it's amd64. Hope this helps
Sidenotes-update-12:15pm 042026
I did the install I described above on an older laptop, windows 10
I just did another complete install on a new laptop, windows 11
I downloaded the following and then installed Java first, then since I have a digitrax DCS52, I installed soundloader which it appears loads the USB driver, then the JMRI
After I installed these I connected the usb cable to my laptop from the DCS52 and it connected with no errors and was able to see the icon go on and off for track power in Decoder pro window
I had to give up the Windows 11 laptop to the wife so I found my MIL's old Dell Inspiron N7010(I think) I had reloaded a year or two ago. Nice big screen and fairly fast.
Downloaded the following:
JMRI.5.15.6+Redb3564a6.exe
microsoftr-jdk-25.0.3-windows-x64.exe ( was the latest)
From the Digitrax website- PR3 WindowsXP Vista32_64.zip
Installed Microsoft JDK first- success
Installed the JMRI software listed above- success
Turned on Digitrax DCS52 and plugged it in. Unable to load the USB driver
Shows up in the Device Manager as VCOM DCS52 with no driver.
I extracted the Digitrax zip file
Then updated the driver and made it look where I had extracted the Digitrax PR3 files
Driver updated successfully.
Started Decoder Pro, started setup it found the USB port(com 8 on my laptop)
Was able to turn track power on and off.
