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--- linux:legomindstorms [2013/12/30 15:42] – rlunaro
+++ linux:legomindstorms [2024/10/05 17:01] (current) – removed rlunaro
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-====== First steps with Lego Mindstorms ======
-===== Intro =====
-My brother has lent me a Lego Mindstorms version 1.5. It is quite old, by the specifications I think that the product may be dated of 1998. **My objective is to make it work under linux** in a modern computer without a serial cable, to let my son work with it.
-{{ :linux:20131230_113225.jpg?direct&400 |}}
-===== Options to have it work under Linux =====
-I will try the following options in the same order depicted here:
-  - Use of [[http://bricxcc.sourceforge.net/nqc/|Not Quite C (nqc)]]: it's a programming language similar to C, that can be used to generate code compatible with the RCX (the brain that goes into the robot)
-  - Use of [[http://www.lejos.org/|Lejos]]: it's a Java Virtual Machine for the RCX. This replaces completely the firmware in the RCX as long as the batteries are connected to the unit (RCX). For me it's a good solution because I am quite familiar with Java, so it's a natural way to go. Unfortunately, this is a major obstacle for my son and presumably I will have to do all the programming stuff...
-  - Use a VirtualBox Windows Machine and run the original software. This option has the advantage that the less problematic. Specially with the RS232, as you will see soon.
-  - Use of Not Quite C, but in a Windows virtual machine.
-  - Use of Lejos, but in a Windows virtual machine.
-===== What??? No RS232??? =====
-Yes, my computer doesn't have a RS232 interface. Hence, I have to simulate it with an special adapter:
-{{ :linux:img-20131230-wa0000.jpg?direct&300 |hola}}
-**The problem is** that this cable comes with a fantastic driver.... for Windows and Mac.
-INSERT HERE PICTURE OF THE DRIVER DISC
-So, the working of this solution depends greatly with the hability or good work of the Ubuntu and Linux engineers.
-===== Before Everything =====
-Don't plug the USB-RS232 adaptor yet!!! Before this, run a ''tail -f /var/log/messages'' or ''tail -f /var/log/syslog'' (depending of your version of Linux). To be sure, just run both at a time:
-<code shell>
-$ sudo tail -f /var/log/messages /var/log/syslog
-</code>
-Now, **plug your cable**. You should view something like this:
-<code>
-Dec 30 12:29:18 petrus kernel: [17198.868053] usb 4-1: new full speed USB device number 3 using uhci_hcd
-Dec 30 12:29:18 petrus mtp-probe: checking bus 4, device 3: "/sys/devices/pci0000:00/0000:00:1a.1/usb4/4-1"
-Dec 30 12:29:18 petrus kernel: [17199.032177] pl2303 4-1:1.0: pl2303 converter detected
-Dec 30 12:29:18 petrus kernel: [17199.044237] usb 4-1: pl2303 converter now attached to ttyUSB0
-Dec 30 12:29:19 petrus mtp-probe: bus: 4, device: 3 was not an MTP device
-</code>
-This **''pl2303 converter now attached to ttyUSB0''** means that your USB device is ''/dev/ttyUSB0''.
-===== First Attempt: Not Quite C =====
-This is my first attempt and my first try to make the USB-RS232 adaptor to work. I know that Java doesn't have a good USB or serial support, so the second try will be a major problem. My hopes are that NQC, as probably is made natively in C or similar, will have a native support for USB/RS-232 more robust.
-__You can find documentation about NQC here: [[http://bricxcc.sourceforge.net/nqc/]]__.
-==== Hands on ====
-You can install nqc in Ubuntu by typing:
-<code shell>
-> sudo apt-get install nqc
-</code>
-You can make a hello world to make sure that the USB-RS232 is working properly.
-**First**, connect the unit to the PC and make sure it's on. The "on" in this unit means to move the swith to the biggest triangle:
-INSERT PICTURE OF THE BLACK UNIT HERE.
-**Next**, turn on the RCX and point it to the black unit, so both can see each other. Remember that the connection is via infrared.
-**Next**, run the following code:
-<code shell>
-nqc -S/dev/ttyUSB0 -msg 123456
-</code>
-When running it, I've observed no error messages and no ''Could not open serial port or USB device'' message. This is important.
-**Other commands to test proper running**
-I've run this command:
-<code shell>
-$ nqc -S/dev/ttyUSB0 -pgm 1
-No firmware installed on RCX
-</code>
-So I'm afraid further investigation is needed.
-**Last try**
-I've attached a motor to the "C" square of the RCX:
-PICTURE HERE OF THE RCX WITH THE MOTOR.
-And this is my first program:
-<code nqc>
-task main()
-{
-    OnFwd( OUT_C );
-    Wait( 400 );
-    OnRev( OUT_C );
-    Wait( 400 );
-    Off( OUT_C );
-}
-</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.
-====Where is the firmware???====
-Check out the box of mindstorm: it should be a CD:
-INSERT PICTURE OF THE CD HERE
-Possible cases you might find here:
-  - The firmware file is in the cd and you can extract directly without hassle. It should be a file like ''firm0309.lgo'' or something like this.
-  - The firmware file is in the CD, but apparently when trying to extract using linux, it fails. This is because the file format of the CD is very old. Try to extract the file using a windows machine or a virtual windows machine. If it is your case, I recommend to make a backup copy of the contents of the CD in another Cd. But copy the contents, not make a copy of the whole cd, because the older filesystem will be kept too.
-  - The firmware file is not in the cd, but it is in one of the *cab files. In that case, you can find instruction in this page:[[http://www.17od.com/2013/01/13/using-lego-mindstorms-on-ubuntu/]]. In a nutshell, ''sudo apt-get install unshield'' and then ''unshield x PATH-TO-YOUR-CAB-FILE''.
-==== Downloading the firmware ====
-In the argot, placing the firmware file in the yellow box (the RCX) is called "download the firmware". I don't know why, because for me is more proper the opposite term (upload), but the terms were set when I came to this world.
-Run the following command:
-<code shell>
-$ nqc -S/dev/ttyUSB0 -firmware firm0309.lgo
-Downloading firmware:.....................
-</code>
-You should see a message in the RCX about the progress of the download:
-INSERT PICTURE HERE
-and a green diode lighting in the black box:
-INSERT PICTURE HERE
-After the process is finished, the LCD screen of the RCX should show a 0000 message, and a sound is reproduced:
-INSERT PICTURE HERE
-The installation of the firmware will be there until the batteries are removed.
-For example, the following command:
-<code>
-nqc -S/dev/ttyUSB0 -pgm 2
-</code>
-Will have the effect that in the RCX the program number 2 is selected:
-INSERT PICTURE HERE
-==== Executing the program ====
-To run and download the program into the RCX, you should do the following:
-<code shell>
-$ nqc -S/dev/ttyUSB0 -d -run Hello.nqc
-Downloading Program:..complete
-Battery Level = 8.7 V
-</code>
-Now, click on the "run" button on the RCX: the program will start, moving the motor in one direction and then in the opposite direction.
-===== Second Attempt: LEJOS =====
-[[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.
-===== Useful Links =====
-  * [[http://www.17od.com/2013/01/13/using-lego-mindstorms-on-ubuntu/]]