Wiki source code of LEGO Mindstorms with leJOS and SCCharts

Last modified by Alexander Schulz-Rosengarten on 2023/09/11 16:17

version	line-number	content
3.1	1	= Program LEGO Mindstorms with leJOS and SCCharts =
	2
	3
	4
	5	{{toc minLevel="2"/}}
	6
	7	----
	8
	9	== Overview ==
	10
21.1	11	Mindstorms is a product family from Lego, with sensors, motors and a programmable brick. The newest iteration of the product family is the EV3 programmable brick. Its predecessors are NXT and RCX. In the following we will see how to develop applications for the NXT brick.
1.1	12
7.1	13	Several open-source, third-party replacements for the offical Lego firmware have been developed. These support many well known programming languages, such as Java, C/C++, Python, Lua, etc. In the following we will use KIELER SCCharts to program Mindstorms running the Lego Java Operating System ([[leJOS>>url:http://www.lejos.org/\|\|shape="rect"]]). Therefore we will first install leJOS NXJ and flash its firmware. Afterwards we will create a simple SCCharts project in KIELER that we will compile and deploy to the NXT brick.
5.1	14
35.1	15	If you want to learn the SCCharts langugage first, you can follow these links:
	16
67.1	17	* [[Introduction to SCCharts>>doc:KIELER.SCCharts (DeprecatedHistorical Documentation & Features).SCCharts (pre 1\.0).WebHome]]
66.1	18	* [[The Textual SCCharts Language SCT>>doc:KIELER.SCCharts (DeprecatedHistorical Documentation & Features).SCCharts (pre 1\.0).Textual SCCharts Language SCT.WebHome]]
61.1	19	* [[SCCharts Examples>>doc:KIELER.TO DELETE.Examples.WebHome]]
35.1	20
3.1	21	----
	22
	23	== Download and install leJOS ==
	24
22.1	25	Download and extract the newest archives for your Operating System from [[Sourceforce>>url:http://sourceforge.net/projects/nxt.lejos.p/files/\|\|shape="rect"]] (Linux/Mac) or use the Setup.exe (Windows).
3.1	26
7.1	27	The further installation is explained in detail at [[http:~~/~~/www.lejos.org/nxt/nxj/tutorial/Preliminaries/GettingStarted.htm>>url:http://www.lejos.org/nxt/nxj/tutorial/Preliminaries/GettingStarted.htm\|\|shape="rect"]].
3.1	28
31.1	29	Do not forget to flash the download leJOS firmware to the Mindstorms brick as explained in the tutorial!
	30
7.1	31	=== Known issues ===
3.1	32
27.1	33	==== Linux ====
17.1	34
7.1	35	On Linux there is an issue when uploading the firmware because of a kernel module ([[http:~~/~~/ubuntuforums.org/showthread.php?t=1123633>>url:http://ubuntuforums.org/showthread.php?t=1123633\|\|shape="rect"]]). If you can't upload the firmware with your Linux OS, add blacklist cdc_acm{{code language="none"}}{{/code}} at the very end of the file {{code language="none"}}/etc/modprobe.d/blacklist.conf{{/code}}. Afterwards execute {{code language="none"}}sudo rmmod cdc_acm{{/code}}. This will remove the cdc_acm module from the kernel and prevent its restart. Now try to flash the firmware again.
3.1	36
17.1	37	Another issue is that the development package of libusb has to be installed. On Ubuntu you can do this by using {{code language="none"}}sudo apt-get install libusb-dev{{/code}}.
	38
30.1	39	Furthermore, to use USB connection, a java library has to be compiled via ant. To do this perform cd /path/to/leJOS/build and start ant. If the ant build tool is not installed on your system, you can do so via sudo apt-get install ant.
17.1	40
27.1	41	==== Windows ====
	42
	43	The setup.exe of the current LEGO Fantom driver for Windows (1.2.0) has an awkward issue. If you get an error message (Developer Error) because an .msi file could not be found, don't panic. The file is part of the downladed archive (in the Products folder) but you have to start it manually.
	44
30.1	45	==== Mac OS X ====
	46
	47	The leJOS NXJ tools require a 32 Bit version of Java. However, newer 32 Bit versions of Java are not longer available for Mac. Thus to use leJOS the installation of Java 1.6 is required, which is the last one that supports a 32 Bit mode. You can download the installer for Java 1.6 from [[https:~~/~~/support.apple.com/kb/dl1572?locale=en_US>>url:https://support.apple.com/kb/dl1572?locale=en_US\|\|shape="rect"]]. It will install Java 1.6 to ///System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Home// so that the environment variable //LEJOS_NXT_JAVA_HOME//, which is set in the installation instructions, points to the correct path.
	48
33.1	49	The environment variable LEJOS_NXT_JAVA_HOME is set in the installation tutorial by editing ~~/.profile. However, on a Mac the environment variables defined in this file are not visible for GUI Applications, only for apps started from terminal. Thus to use leJOS together with KIELER, one either has to start KIELER from terminal or set the environment variable so that all GUI applications can access it. However, this does not seem to be trivial on Mac (see also [[http:~~/~~/stackoverflow.com/questions/135688/setting-environment-variables-in-os-x>>url:http://stackoverflow.com/questions/135688/setting-environment-variables-in-os-x\|\|shape="rect"]]).
30.1	50
3.1	51	----
	52
7.1	53	== Test the Mindstorm ==
3.1	54
7.1	55	A simple Hello World application for the Mindstorms is developed as part of the leJOS tutorial [[http:~~/~~/www.lejos.org/nxt/nxj/tutorial/Preliminaries/FirstProgram.htm>>url:http://www.lejos.org/nxt/nxj/tutorial/Preliminaries/FirstProgram.htm\|\|shape="rect"]]
3.1	56
27.1	57	If this works with your device, you are able to start using KIELER to develop applications for the NXT brick.
3.1	58
	59	----
	60
45.1	61	== Download and Configure KIELER ==
27.1	62
45.1	63	== ==
27.1	64
55.1	65	Download and unpack the nightly build of KIELER for your OS. It is available at the [[doc:KIELER.Overview.Downloads.WebHome]] page.\\
45.1	66
33.1	67	Note: Java 1.8 is needed on all operating systems. With Java 1.7 not all plugins of KIELER will be loaded. Furthermore on Windows, you will need to download the 32 Bit version of KIELER – even if you have a 64 bit operating system! Otherwise flashing the brick and uploading to the brick will fail.
27.1	68
28.1	69	=== The Eclipse plugin for leJOS ===
27.1	70
24.1	71	There is an Eclipse plugin for leJOS which adds a project creation wizard and launch configuration to the platform.
3.1	72
24.1	73	1. You have to install it via the Eclipse Marketplace (//Help > Eclipse Marketplace...//).
	74	OR
25.1	75	1. Install the plugin manually (Help > Install new Software...). Use the following update site\\
	76	11. for NXT: [[http:~~/~~/www.lejos.org/tools/eclipse/plugin/nxj/>>url:http://www.lejos.org/tools/eclipse/plugin/nxj/\|\|shape="rect"]]
	77	11. for EV3: [[http:~~/~~/www.lejos.org/tools/eclipse/plugin/ev3/>>url:http://www.lejos.org/tools/eclipse/plugin/ev3/\|\|shape="rect"]]
24.1	78
25.1	79	If you have an NXT brick, install the leJOS NXJ Plug-in. If you have an EV3 brick, install the leJOS EV3 plugin.
	80
40.1	81	[[image:attach:Screenshot_20171016_130805.png]]
	82
37.1	83	Tip: To speed up the installation, uncheck the option "Contact all update sites during install to find required software". This will reduce the installation time from drastically (around 30 seconds instead 10 minutes).
	84
40.1	85	\\
8.1	86
28.1	87	After the installation, the plugin requires a little configuration. Go to //Window > Preferences > leJOS NXJ// (//Window > Preferences > leJOS EV3 //respectively) and enter the base directory of your leJOS installation in the NXJ_HOME field.
19.1	88
33.1	89	For EV3, the plugin requires the IP address to connect to the brick (it may work without, but its safer to directly set the name. Reduces headache ). Check Connect to named brick and enter the IP adress of the brick (displayed on the brick at startup).
3.1	90
	91	----
	92
14.1	93	== Creating an Example Project ==
	94
33.1	95	The following shows how to create a project, which will turn on a light if a button is pressed.
14.1	96
15.1	97	=== Create a new project: ===
14.1	98
18.1	99	1. Choose //File > New > Project > KIELER SCCharts > SCCharts Project//
21.1	100	1. In the project creation wizard that opens, select //Mindstorms NXJ// or// Mindstorms EV3// (depending on your brick) as environment and hit //finish//
14.1	101	1. The project wizard from the leJOS plugin opens. Set the project name to //Flashlight// and click //finish//.
	102	1. The project is created and the model file is opened in an editor (This might take a few seconds).
	103
40.1	104	=== Edit the Model: ===
14.1	105
	106	Change the contents of the model file to the following code and save it.
	107
32.1	108	{{code language="sct" theme="Eclipse" title="Floodlight.sct"}}
14.1	109	scchart Flashlight {
	110
	111	@Wrapper TouchSensor, S4
	112	input bool button;
	113
	114	@Wrapper Floodlight, S1
	115	output bool light;
	116
	117	initial state lightOff
	118	--> lightOn with button / light = true;
	119
	120	state lightOn
	121	--> lightOff with !button / light = false;
	122	}
	123	{{/code}}
	124
	125	This model will start in the state lightOff. If the button is pressed, it will turn on the light and change to the corresponding state, where the light is turned off, as soon as the button is not pressed anymore.
	126
21.1	127	The annotations on the input and output variable are used to define which wrapper code is used to set / read them. @Wrapper TouchSensor, S4 will set the input variable to true iff the touch sensor on the port S4 is pressed. @Wrapper Floodlight, S1 on the output variable will turn on the red led of the light sensor that is attatched to port S1 iff the variable is true.
	128
40.1	129	The available wrapper code snippets are defined in the directory //assets/snippets// in ftl files (FreeMarker template files). The table below gives an overview of the available wrapper code snippets.
21.1	130
26.1	131	Note: The Floodlight of the EV3 has a pretty high latency when switching between on and off.
	132
39.1	133	Note: To view ftl files with highlighting, you may want to install the //FreeMarker IDE// feature from the JBoss Tools. However, this is not necessary to work with KIELER. JBoss Tools is available in the Eclipse Market Place and via update site. The update site for stable releases is [[http:~~/~~/download.jboss.org/jbosstools/neon/stable/updates/ >>url:http://download.jboss.org/jbosstools/neon/stable/updates/\|\|shape="rect"]]. Note that only the //FreeMarker IDE// feature is required (Abridged JBoss Tools > FreeMarker IDE).**
14.1	134	**
	135
40.1	136	=== Build the Project: ===
14.1	137
40.1	138	The model is now ready to be compiled. Compilation is done in the background when the project is built. There are two ways to build a project: manually using //Project > Build Project//, or automatically via //Project > Build Automatically//. If the automatic build is enabled, resources are built when they are saved.
14.1	139
40.1	140	Building the project will create a new folder //kieler-gen// in which all results are saved. This includes the compiled code from the model, an executable simulation for the model and wrapper code that is ready to be deployed to the Mindstorms Brick.
18.1	141
40.1	142	The simulation is saved as JAR file in //kieler-gen/sim/bin// and can be started via //Right Click > Run as > KIELER Simulation//. Models and variables of a running simulation are displayed in the Data Pool View.
19.1	143
40.1	144	[[image:attach:Screenshot_20171016_110005.png]]
	145
	146	Besides the simulation, the finished wrapper code that can be uploaded to the Mindstorms brick is created as part of the project build. It is saved in //kieler-gen/model//. To upload it to the Mindstorms brick, use //Right Click > Run as > leJOS NXT Program//.
	147
	148	[[image:attach:Screenshot_20171016_120554.png]]
	149
	150	==== Excluding the Simulation from the NXT Build ====
	151
	152	It is necessary to exclude the simulation directory and org.json directory inside kieler-gen from the NXT project specific build via //Right Click > Build Path > Exclude//. Afterwards the project has to be build again to remove all error markers in these directories.
	153
	154	[[image:attach:Screenshot_20171016_105821.png]]
	155
	156	Normally the NXT project attempts to compile all Java files in the kieler-gen directory for the platform. However, the simulation that is generated is not targeted at the Mindstorms brick and has compilation errors. It is compiled separately by KIELER.
	157
33.1	158	=== Available Wrapper Code Snippets ===
	159
40.1	160	There are several wrapper code snippets that can be used as annotations on input and output variables in the model file. These snippets are inserted in the main file template as part of the project build. The available snippets are listed below.
33.1	161
	162	For sensors, the port has to be on of S1, S2, S3, S4.
	163
34.1	164	For motors / actuators the port has to be one of A, B, C, D.
33.1	165
35.1	166	(% class="wrapped" %)
33.1	167	\|=(((
	168	Snippet Name and Parameters
	169	)))\|=(((
	170	Description
	171	)))\|=(((
	172	Use on
	173	)))\|=(% colspan="1" %)(% colspan="1" %)
	174	(((
	175	Variable type
	176	)))\|=(((
	177	Remark
34.1	178	)))\|=(% colspan="1" %)(% colspan="1" %)
	179	(((
	180	Defined in File
33.1	181	)))
	182	\|(% colspan="1" %)(% colspan="1" %)
	183	(((
	184	Clock, milliseconds
	185	)))\|(% colspan="1" %)(% colspan="1" %)
	186	(((
36.1	187	Sets a variable to true for one tick if the time in milliseconds passed since the last time it was set to true.
33.1	188	)))\|(% colspan="1" %)(% colspan="1" %)
	189	(((
	190	input
	191	)))\|(% colspan="1" %)(% colspan="1" %)
	192	(((
	193	bool
	194	)))\|(% colspan="1" %)(% colspan="1" %)
	195	(((
	196	See also ResetClock.
34.1	197	)))\|(% colspan="1" %)(% colspan="1" %)
	198	(((
	199	timing.ftl
33.1	200	)))
	201	\|(% colspan="1" %)(% colspan="1" %)
	202	(((
	203	ResetClock, clockVariableName, autoFalse
	204	)))\|(% colspan="1" %)(% colspan="1" %)
	205	(((
	206	Resets a clock, such that the full time intervall of the clock has to elapse, before the clock will be set to true again.
	207
	208	If autoFalse is true, the reset variable will be set to false automatically.
	209	)))\|(% colspan="1" %)(% colspan="1" %)
	210	(((
	211	output
	212	)))\|(% colspan="1" %)(% colspan="1" %)
	213	(((
	214	bool
	215	)))\|(% colspan="1" %)(% colspan="1" %)
	216	(((
	217	autoFalse is true per default.
34.1	218	)))\|(% colspan="1" %)(% colspan="1" %)
	219	(((
	220	timing.ftl
33.1	221	)))
	222	\|(% colspan="1" %)(% colspan="1" %)
	223	(((
	224	Time
	225	)))\|(% colspan="1" %)(% colspan="1" %)
	226	(((
41.1	227	Reads the elapsed time since program start (milliseconds)
33.1	228	)))\|(% colspan="1" %)(% colspan="1" %)
	229	(((
	230	input
	231	)))\|(% colspan="1" %)(% colspan="1" %)
	232	(((
	233	int
	234	)))\|(% colspan="1" %)(% colspan="1" %)
	235	(((
39.1	236	\\
34.1	237	)))\|(% colspan="1" %)(% colspan="1" %)
	238	(((
	239	timing.ftl
33.1	240	)))
	241	\|(% colspan="1" %)(% colspan="1" %)
	242	(((
38.1	243	TickLoopDuration, targetInMilliseconds
33.1	244	)))\|(% colspan="1" %)(% colspan="1" %)
	245	(((
	246	Delays the execution until the tick loop takes at least as long as the given target duration.
	247
	248	The input variable is set to the actual tick loop duration.
	249	)))\|(% colspan="1" %)(% colspan="1" %)
	250	(((
	251	input
	252	)))\|(% colspan="1" %)(% colspan="1" %)
	253	(((
	254	int
	255	)))\|(% colspan="1" %)(% colspan="1" %)
	256	(((
	257	Should be used on the very first input variable in the model, such that waiting is the last action in the tick loop.
41.1	258
	259	In case the actual tick loop duration is longer than the target duration, the modeler can provide some error handling.
34.1	260	)))\|(% colspan="1" %)(% colspan="1" %)
	261	(((
	262	timing.ftl
33.1	263	)))
	264	\|(% colspan="1" %)(% colspan="1" %)
	265	(((
38.1	266	TickWakeUp
	267	)))\|(% colspan="1" %)(% colspan="1" %)
	268	(((
41.1	269	(% class="content-wrapper" %)
	270	(((
	271	Sets the input variable to the current system time (milliseconds). The model can add to this variable to get a new value. This is the next system time the tick function will be called.
38.1	272
41.1	273	In other words, the next tick function call is delayed until the wake up time has been reached.
	274
	275	For instance the statement nextTickWakeUp += 500 could be used to call the tick function again in 500 milliseconds, if nextTickWakeUp is an input with the corresponding annotation.
	276	)))
38.1	277	)))\|(% colspan="1" %)(% colspan="1" %)
	278	(((
	279	input
	280	)))\|(% colspan="1" %)(% colspan="1" %)
	281	(((
	282	int
	283	)))\|(% colspan="1" %)(% colspan="1" %)
	284	(((
	285	Should be used on the very last input variable in the model, such that waiting and settings the system time is the last action done, before the tick function call.
	286	)))\|(% colspan="1" %)(% colspan="1" %)
	287	(((
	288	timing.ftl
	289	)))
	290	\|(% colspan="1" %)(% colspan="1" %)
	291	(((
42.1	292	TickCount
	293	)))\|(% colspan="1" %)(% colspan="1" %)
	294	(((
	295	Counts the ticks. First tick is 0, the following are 1, 2, 3, ...
	296	)))\|(% colspan="1" %)(% colspan="1" %)
	297	(((
	298	input
	299	)))\|(% colspan="1" %)(% colspan="1" %)
	300	(((
	301	int
	302	)))\|(% colspan="1" %)(% colspan="1" %)
	303	(((
	304	\\
	305	)))\|(% colspan="1" %)(% colspan="1" %)
	306	(((
	307	timing.ftl
	308	)))
	309	\|(% colspan="1" %)(% colspan="1" %)
	310	(((
33.1	311	Sleep
	312	)))\|(% colspan="1" %)(% colspan="1" %)
	313	(((
	314	Lets the current thread sleep the time in milliseconds of the variable value.
	315	)))\|(% colspan="1" %)(% colspan="1" %)
	316	(((
	317	output
	318	)))\|(% colspan="1" %)(% colspan="1" %)
	319	(((
	320	int
	321	)))\|(% colspan="1" %)(% colspan="1" %)
	322	(((
39.1	323	\\
34.1	324	)))\|(% colspan="1" %)(% colspan="1" %)
	325	(((
	326	timing.ftl
33.1	327	)))
	328	\|(% colspan="1" %)(% colspan="1" %)
	329	(((
	330	Print, autoReset
	331	)))\|(% colspan="1" %)(% colspan="1" %)
	332	(((
	333	Prints a string variable if the string is not empty. If autoReset is true then the string variable is set to the empty string after it has been printed
	334	)))\|(% colspan="1" %)(% colspan="1" %)
	335	(((
	336	output
	337	)))\|(% colspan="1" %)(% colspan="1" %)
	338	(((
	339	string
	340	)))\|(% colspan="1" %)(% colspan="1" %)
	341	(((
	342	autoReset is true per default.
34.1	343	)))\|(% colspan="1" %)(% colspan="1" %)
	344	(((
	345	print.ftl
33.1	346	)))
	347	\|(% colspan="1" %)(% colspan="1" %)
	348	(((
	349	DrawString, x, y
	350	)))\|(% colspan="1" %)(% colspan="1" %)
	351	(((
	352	Prints a string to the given x and y coordinate on the LCD.
	353	)))\|(% colspan="1" %)(% colspan="1" %)
	354	(((
	355	output
	356	)))\|(% colspan="1" %)(% colspan="1" %)
	357	(((
	358	string
	359	)))\|(% colspan="1" %)(% colspan="1" %)
	360	(((
39.1	361	\\
34.1	362	)))\|(% colspan="1" %)(% colspan="1" %)
	363	(((
	364	print.ftl
33.1	365	)))
	366	\|(% colspan="1" %)(% colspan="1" %)
	367	(((
	368	Button, buttonId
	369	)))\|(% colspan="1" %)(% colspan="1" %)
	370	(((
	371	Sets a variable to true iff the button on the Mindstorms device is pressed.
	372	)))\|(% colspan="1" %)(% colspan="1" %)
	373	(((
	374	input
	375	)))\|(% colspan="1" %)(% colspan="1" %)
	376	(((
	377	bool
	378	)))\|(% colspan="1" %)(% colspan="1" %)
	379	(((
	380	The buttonId has to be one of ENTER, LEFT, RIGHT
34.1	381	)))\|(% colspan="1" %)(% colspan="1" %)
	382	(((
	383	touch_and_buttons.ftl
33.1	384	)))
	385	\|(% colspan="1" %)(% colspan="1" %)
	386	(((
	387	TouchSensor, port
	388	)))\|(% colspan="1" %)(% colspan="1" %)
	389	(((
	390	Sets a variable to true iff the touch sensor on the given port is pressed.
	391	)))\|(% colspan="1" %)(% colspan="1" %)
	392	(((
	393	input
	394	)))\|(% colspan="1" %)(% colspan="1" %)
	395	(((
	396	bool
	397	)))\|(% colspan="1" %)(% colspan="1" %)
	398	(((
39.1	399	\\
34.1	400	)))\|(% colspan="1" %)(% colspan="1" %)
	401	(((
	402	touch_and_buttons.ftl
33.1	403	)))
	404	\|(% colspan="1" %)(% colspan="1" %)
	405	(((
	406	LightSensor, port, percentValue
	407	)))\|(% colspan="1" %)(% colspan="1" %)
	408	(((
	409	Reads the value of a light sensor.
	410
	411	If percentValue is true, the a percent value is retured, based on the light sensor calibration.
	412	)))\|(% colspan="1" %)(% colspan="1" %)
	413	(((
	414	input
	415	)))\|(% colspan="1" %)(% colspan="1" %)
	416	(((
	417	int
	418	)))\|(% colspan="1" %)(% colspan="1" %)
	419	(((
	420	percentValue is not available on EV3
34.1	421	)))\|(% colspan="1" %)(% colspan="1" %)
	422	(((
	423	light.ftl
33.1	424	)))
	425	\|(% colspan="1" %)(% colspan="1" %)
	426	(((
	427	CalibrateLightSensor, port, signal
	428	)))\|(% colspan="1" %)(% colspan="1" %)
	429	(((
	430	Calibrates a light sensors high or low values. This means if the variable is true, the current value of the light sensor is taken as its reference high / low value.
	431	)))\|(% colspan="1" %)(% colspan="1" %)
	432	(((
	433	output
	434	)))\|(% colspan="1" %)(% colspan="1" %)
	435	(((
	436	bool
	437	)))\|(% colspan="1" %)(% colspan="1" %)
	438	(((
	439	signal has to be one of High, Low
34.1	440	)))\|(% colspan="1" %)(% colspan="1" %)
	441	(((
	442	light.ftl
33.1	443	)))
	444	\|(% colspan="1" %)(% colspan="1" %)
	445	(((
	446	Floodlight, port
	447	)))\|(% colspan="1" %)(% colspan="1" %)
	448	(((
	449	Reads / Sets the state of the red lamp of the light sensor.
	450	)))\|(% colspan="1" %)(% colspan="1" %)
	451	(((
	452	input
	453
	454	output
	455	)))\|(% colspan="1" %)(% colspan="1" %)
	456	(((
	457	bool
	458	)))\|(% colspan="1" %)(% colspan="1" %)
	459	(((
39.1	460	\\
34.1	461	)))\|(% colspan="1" %)(% colspan="1" %)
	462	(((
	463	light.ftl
33.1	464	)))
	465	\|(% colspan="1" %)(% colspan="1" %)
	466	(((
	467	RCXLamp, port
	468	)))\|(% colspan="1" %)(% colspan="1" %)
	469	(((
	470	Turns an RCX lamp on (variable is true) or off (variable is false)
	471	)))\|(% colspan="1" %)(% colspan="1" %)
	472	(((
	473	output
	474	)))\|(% colspan="1" %)(% colspan="1" %)
	475	(((
	476	bool
	477	)))\|(% colspan="1" %)(% colspan="1" %)
	478	(((
39.1	479	\\
34.1	480	)))\|(% colspan="1" %)(% colspan="1" %)
	481	(((
	482	light.ftl
33.1	483	)))
	484	\|(% colspan="1" %)(% colspan="1" %)
	485	(((
	486	MotorSpeed, port, brake
	487	)))\|(% colspan="1" %)(% colspan="1" %)
	488	(((
	489	Reads / Sets the speed of the motor in degrees per minute. If the speed value is negative, the motor will drive backwards. If the speed is zero, the motor will actively brake until it stops (brake is true) or remove all power and rollout (brake is false).
	490	)))\|(% colspan="1" %)(% colspan="1" %)
	491	(((
	492	input
	493
	494	output
	495	)))\|(% colspan="1" %)(% colspan="1" %)
	496	(((
	497	int
	498	)))\|(% colspan="1" %)(% colspan="1" %)
	499	(((
	500	brake is true per default.
34.1	501	)))\|(% colspan="1" %)(% colspan="1" %)
	502	(((
	503	motor.ftl
33.1	504	)))
	505	\|(% colspan="1" %)(% colspan="1" %)
	506	(((
	507	MotorIsMoving, port
	508	)))\|(% colspan="1" %)(% colspan="1" %)
	509	(((
	510	Sets a variable to true iff the motor on the given port is moving.
	511	)))\|(% colspan="1" %)(% colspan="1" %)
	512	(((
	513	input
	514	)))\|(% colspan="1" %)(% colspan="1" %)
	515	(((
	516	bool
	517	)))\|(% colspan="1" %)(% colspan="1" %)
	518	(((
39.1	519	\\
34.1	520	)))\|(% colspan="1" %)(% colspan="1" %)
	521	(((
	522	motor.ftl
33.1	523	)))
	524	\|(% colspan="1" %)(% colspan="1" %)
	525	(((
	526	MotorRotation, port
	527	)))\|(% colspan="1" %)(% colspan="1" %)
	528	(((
	529	Lets a motor rotate the variable value in degrees. This is only done if the value is unequal zero. If the value is negative, the motor rotates backwards. The variable is set to zero afterwards, such that setting the variable once to a value //X//, will let the motor rotate //X// degrees.
	530	)))\|(% colspan="1" %)(% colspan="1" %)
	531	(((
	532	output
	533	)))\|(% colspan="1" %)(% colspan="1" %)
	534	(((
	535	int
	536	)))\|(% colspan="1" %)(% colspan="1" %)
	537	(((
39.1	538	\\
34.1	539	)))\|(% colspan="1" %)(% colspan="1" %)
	540	(((
	541	motor.ftl
33.1	542	)))
	543	\|(% colspan="1" %)(% colspan="1" %)
	544	(((
	545	Beep, volume
	546	)))\|(% colspan="1" %)(% colspan="1" %)
	547	(((
	548	Plays a beep sound as long as the variable is true.
	549	)))\|(% colspan="1" %)(% colspan="1" %)
	550	(((
	551	output
	552	)))\|(% colspan="1" %)(% colspan="1" %)
	553	(((
	554	bool
	555	)))\|(% colspan="1" %)(% colspan="1" %)
	556	(((
	557	default volume is 10
34.1	558	)))\|(% colspan="1" %)(% colspan="1" %)
	559	(((
	560	sound.ftl
33.1	561	)))
	562	\|(% colspan="1" %)(% colspan="1" %)
	563	(((
	564	Buzz, volume
	565	)))\|(% colspan="1" %)(% colspan="1" %)
	566	(((
	567	Plays a buzz sound as long as the variable is true.
	568	)))\|(% colspan="1" %)(% colspan="1" %)
	569	(((
	570	output
	571	)))\|(% colspan="1" %)(% colspan="1" %)
	572	(((
	573	bool
	574	)))\|(% colspan="1" %)(% colspan="1" %)
	575	(((
	576	default volume is 10
34.1	577	)))\|(% colspan="1" %)(% colspan="1" %)
	578	(((
	579	sound.ftl
33.1	580	)))
	581	\|(% colspan="1" %)(% colspan="1" %)
	582	(((
	583	BeepSequence, direction, volume
	584	)))\|(% colspan="1" %)(% colspan="1" %)
	585	(((
	586	Plays a sequence of tones in either ascending or descending tone frequency if the variable is true.
	587
	588	The variable is set to false automatically.
	589	)))\|(% colspan="1" %)(% colspan="1" %)
	590	(((
	591	output
	592	)))\|(% colspan="1" %)(% colspan="1" %)
	593	(((
	594	bool
	595	)))\|(% colspan="1" %)(% colspan="1" %)
	596	(((
	597	direction has to be one of Up, Down
	598
	599	default volume is 10
34.1	600	)))\|(% colspan="1" %)(% colspan="1" %)
	601	(((
	602	sound.ftl
33.1	603	)))
	604	\|(% colspan="1" %)(% colspan="1" %)
	605	(((
	606	UltrasonicSensor, port
	607	)))\|(% colspan="1" %)(% colspan="1" %)
	608	(((
	609	Reads the distance that an ultrasonic sensor measures.
	610	)))\|(% colspan="1" %)(% colspan="1" %)
	611	(((
	612	input
	613	)))\|(% colspan="1" %)(% colspan="1" %)
	614	(((
	615	int
	616	)))\|(% colspan="1" %)(% colspan="1" %)
	617	(((
39.1	618	\\
34.1	619	)))\|(% colspan="1" %)(% colspan="1" %)
	620	(((
	621	ultrasonic.ftl
33.1	622	)))
	623	\|(% colspan="1" %)(% colspan="1" %)
	624	(((
	625	Gyro, port, mode
	626	)))\|(% colspan="1" %)(% colspan="1" %)
	627	(((
	628	Reads the value of a gyroscope.
	629	)))\|(% colspan="1" %)(% colspan="1" %)
	630	(((
	631	input
	632	)))\|(% colspan="1" %)(% colspan="1" %)
	633	(((
	634	int
	635	)))\|(% colspan="1" %)(% colspan="1" %)
	636	(((
	637	Not available on NXT
	638
	639	mode hat to be one of Angle, Rate
34.1	640	)))\|(% colspan="1" %)(% colspan="1" %)
	641	(((
	642	gyro.ftl
33.1	643	)))
	644	\|(% colspan="1" %)(% colspan="1" %)
	645	(((
	646	CalibrateGyro, port, autoReset
	647	)))\|(% colspan="1" %)(% colspan="1" %)
	648	(((
	649	Resets a gyroscope if the variable is true.
	650
	651	If autoReset is true, the variable is set to false automatically.
	652	)))\|(% colspan="1" %)(% colspan="1" %)
	653	(((
	654	output
	655	)))\|(% colspan="1" %)(% colspan="1" %)
	656	(((
	657	bool
	658	)))\|(% colspan="1" %)(% colspan="1" %)
	659	(((
	660	autoReset is true per default
34.1	661	)))\|(% colspan="1" %)(% colspan="1" %)
	662	(((
	663	gyro.ftl
33.1	664	)))
	665
39.1	666	\\
33.1	667
19.1	668	----
	669
	670	== Using the Remote Console (RConsole) ==
	671
21.1	672	The display of the NXT brick is rather small compared to a Monitor. To ease debugging, one can print to a Remote Console (RConsole), if the USB cable is connected. This enables easier collection for example of sensor data.
19.1	673
21.1	674	To use the RConsole, uncomment the RConsole lines in the wrapper code template Main.ftl. Start the nxjconsoleviewer tool in the bin directory of your leJOS installation. Now, when starting the application, the brick tries to connect with the nxjconsoleviewer. Press the //Connect// button. If connected succesfully, RConsole.println(...) commands will be written to this window.
19.1	675
21.1	676	The EV3 brick has a similar feature. However it does not require any code changes. Just run the ev3console program in the bin directory of your leJOS installation from command line. The output of the brick will be printed to this command line.
23.1	677
	678	----
	679
	680	== Problem Solving ==
	681
	682	The following presents typical issues and how to solve them.
	683
35.1	684	(% class="wrapped" %)
23.1	685	\|=(((
	686	Issue
	687	)))\|=(((
	688	Typical Error Messages
	689	)))\|=(((
	690	Description
	691	)))\|=(((
	692	Solution
	693	)))
	694	\|(((
	695	leJOS EV3 does not support Java 8
	696	)))\|(((
	697	"java.lang.UnsupportedClassVersionError"
	698
	699	"unsupported major.minor version"
	700	)))\|(((
	701	You compile the sources in your project with Java 8 and upload them to the brick. However the lejos EV3 does not support Java 8
	702	)))\|(((
	703	Go to the project properties and switch to Java 7 (Right Click on project > Properties > Java Compiler > Compiler compliance level)
	704	)))
31.1	705	\|(% colspan="1" %)(% colspan="1" %)
	706	(((
	707	Uploading to the brick does not respond
	708	)))\|(% colspan="1" %)(% colspan="1" %)
	709	(((
39.1	710	\\
31.1	711	)))\|(% colspan="1" %)(% colspan="1" %)
	712	(((
	713	You compile a file successfully and when uploading the result, the connected brick is found. Anyway the upload does not terminate and does not react.
	714	)))\|(% colspan="1" %)(% colspan="1" %)
	715	(((
	716	Flash the brick with the current leJOS firmware. If the brick is recognized correctly and the attempt to upload a compiled file fails then the firmware on the brick might be outdated.
	717	)))
	718	\|(% colspan="1" %)(% colspan="1" %)
	719	(((
	720	Compilation and uploading works from command line but not when using KIELER
	721	)))\|(% colspan="1" %)(% colspan="1" %)
	722	(((
	723	This Java instance does not support a 32-bit JVM. Please install the desired version.
	724	)))\|(% colspan="1" %)(% colspan="1" %)
	725	(((
	726	You can compile and upload code to the brick using the command line tools but when using KIELER an error message apprears because Java does not support 32-bit JVM.
	727	)))\|(% colspan="1" %)(% colspan="1" %)
	728	(((
	729	Set the LEJOS_NXT_JAVA_HOME environment variable, such that it points to an 32-bit JDK and is visible for GUI applications (or at least KIELER). The process to do so differs on every OS. As alternative, execute KIELER from terminal.
	730	)))
32.1	731	\|(% colspan="1" %)(% colspan="1" %)
	732	(((
	733	Brick does nothing after program finished and prints "Program exit"
	734	)))\|(% colspan="1" %)(% colspan="1" %)
	735	(((
39.1	736	\\
32.1	737	)))\|(% colspan="1" %)(% colspan="1" %)
	738	(((
	739	A program was uploaded and finished without errors. Afterwards the brick prints "Program exit" but does not open the main menu.
	740	)))\|(% colspan="1" %)(% colspan="1" %)
	741	(((
	742	This is normal behaviour if uploading a program in debug mode instead run mode (//Debug As// instead //Run As// in Eclipse). To get back to the main menu, press the ENTER and ESCAPE button of the brick at the same time.
	743	)))
23.1	744
39.1	745	\\
23.1	746
39.1	747	\\

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