<p>I am trying to get an old RCX working with leJOS. I already have it working with NQC and BricxCC.</p>

<p>While NCQ/BricxCC seems to recognize my usb-to-serial (which appears as "COM5" to the OS), the leJOS I downloaded does not. I believe that it uses <a href="http://jlog.org/rxtx-win.html" rel="nofollow">Java rxtx</a> on Windows to access the serial port.</p>

<p>There seems to be a number of pieces I will need to get into place to make it work.  </p>

<p>I am running Windows 7 professional Version 6.1 (Build 7601:Service Pack 1) on my work laptop (I have OS X on the desktop at home - I suppose I could boot to Linux from a USB or CD on my work machine if I really needed to.)</p>

<p>If I stick with Windows 7 I will need a version of the RXTX DLL which works with:</p>

<ol>
<li>this version of Windows</li>
<li>my COM5 port (which is really usb-to-serial).  </li>
</ol>

<p>I also need a version of Java which works with the leJOS java source code, (found some references that not all JVM versions work) and that version of RXTX/DLL and the RCX (not the NXT...I don't own one).</p>

<p>Alternatively I figure I can upload the leJOS firmware with NQC, but after an hour of trying different searches on the internet I can not find the location/name of the firmware file, or build instructions.</p>

<p>The leJOS forum looks like no-one has posted to the RCX section since 2014, so I thought I might try here.</p>

<p>I'd prefer a Windows 7 solution (as that is where BricxCC and NCQ live now), but I would be willing to consider alternatives if no Windows 7 solution exists.</p>

<mindstorms><software><rcx><lejos>
RCX + java + usb-to-serial
Fenn
# RCX + java + usb-to-serial

(Asked by: username_0 on 2015-04-04)

I am trying to get an old RCX working with leJOS. I already have it working with NQC and BricxCC.

While NCQ/BricxCC seems to recognize my usb-to-serial (which appears as "COM5" to the OS), the leJOS I downloaded does not. I believe that it uses [Java rxtx](http://jlog.org/rxtx-win.html) on Windows to access the serial port.

There seems to be a number of pieces I will need to get into place to make it work.

I am running Windows 7 professional Version 6.1 (Build 7601:Service Pack 1) on my work laptop (I have OS X on the desktop at home - I suppose I could boot to Linux from a USB or CD on my work machine if I really needed to.)

If I stick with Windows 7 I will need a version of the RXTX DLL which works with:

1. this version of Windows
2. my COM5 port (which is really usb-to-serial).

I also need a version of Java which works with the leJOS java source code, (found some references that not all JVM versions work) and that version of RXTX/DLL and the RCX (not the NXT...I don't own one).

Alternatively I figure I can upload the leJOS firmware with NQC, but after an hour of trying different searches on the internet I can not find the location/name of the firmware file, or build instructions.

The leJOS forum looks like no-one has posted to the RCX section since 2014, so I thought I might try here.

I'd prefer a Windows 7 solution (as that is where BricxCC and NCQ live now), but I would be willing to consider alternatives if no Windows 7 solution exists.

**Tags:** mindstorms, software, rcx, lejos


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## 0 answers

