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--- linux:legomindstorms [2013/12/31 20:44] – rlunaro
+++ linux:legomindstorms [2014/01/07 23:46] – rlunaro
@@ Line 145: / Line 145: @@
+==== My first program ====
-So I'm afraid further investigation is needed.
-**Last try**
 I've attached a motor to the "C" square of the RCX:
@@ Line 160: / Line 154: @@
 And this is my first program:
-<code nqc>
+<code c>
 task main()
 {
@@ Line 173: / Line 167: @@
 </code>
-When I try to run it, I get the following error:
-<code shell>
-$ nqc -S/dev/ttyUSB0 -run Hello.nqc
-No firmware installed on RCX
-</code>
-So, I definitely think that the RCX is completely blank, and I have to install some sort of firmware to have it properly working.
----------
-==== Executing the program ====
 To run and download the program into the RCX, you should do the following:
@@ Line 200: / Line 181: @@
 ===== Second Attempt: LEJOS =====
+==== Install ant ====
+You should have ''ant'' installed. To do so,
+<code shell>
+$ sudo apt-get install ant
+</code>
+And should have ''libusb-dev'' installed also.
+<code shell>
+sudo apt-get install libusb-dev
+</code>
+After doing that, make sure that the usb.h file is available in your destination system.
+==== Hands on ====
 [[http://www.lejos.org/|Lejos]] is a Java Virtual Machine for the RCX (the yellow box). It's a replacement for the Lego firmware, so, if your CD of mindstorms is broken, it's the perfect solution.
 The web page has a [[http://www.lejos.org/rcx/tutorial/index.html|fantastic tutorial]] that shows the steps to be taken to have this stuff running.
+When I've checked out the web page, the download link didn't work. But you can go directly to the [[http://sourceforge.net/projects/lejos|sourceforge webpage]] in order to download the files.
+When you download and uncompress the file ''leJOS_NXJ_0.9.1beta-3.tar.gz'', you should check out the README.html file.
+Then start by setting the environment variable NXJ_HOME:
+<code shell>
+$ cd LEJOS_NXJ_DIRECTORY   # the files ACKNOWLEDGMENTS.txt, LICENSE.txt, RELEASENOTES.txt should be there
+$ NXJ_HOME=$(pwd)
+$ export NXJ_HOME
+</code>
+Then go to the ''build'' directory and run ''ant''. This is for construct the USB support for java.
+In my case, this command failed. The problem was in the ''build.xml'' file located in NXJ_HOME/build/libnxt. I've reconstructed the compiler command:
+<code shell>
+gcc -Wall -std=gnu99 -fPIC main_jlibnxt.c
+</code>
+And it fails with this error:
+<code>
+main_jlibnxt.c:28:17: fatal error: usb.h: No such file or directory
+</code>
+**Solution:**
+    - Locate the usb.h file in your filesystem: ''find / -iname usb.h 2>/dev/null'': in my system this appears in ''/usr/include/usb.h''
+I've fixed the solution executing the ''make'' command and then:
+<code shell>
+$ cd NXJ_HOME/build
+$ ant
+</code>