All programs from Lesson 1

Lesson 1 - Exercise 1 - LineFollower/.classpath

+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="con" path="org.lejos.nxt.ldt.LEJOS_LIBRARY_CONTAINER/nxt"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>

Lesson 1 - Exercise 1 - LineFollower/.project

+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>Lesson 1 - Exercise 1 - LineFollower</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.lejos.nxt.ldt.leJOSBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.lejos.nxt.ldt.leJOSNature</nature>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>

Lesson 1 - Exercise 1 - LineFollower/src/LineFollower.java

+import lejos.nxt.*;
+
+/**
+ * A simple line follower for the LEGO 9797 car with a single light sensor.
+ * 
+ * The light sensor should be connected to port 3. The left motor should be
+ * connected to port C and the right motor to port B.
+ * 
+ * Variables initialized with a constant string are used in the LCD.drawString
+ * calls of the control loop to avoid frequent garbage collection.
+ * 
+ * @author Ole Caprani
+ * @version 4.02.12
+ */
+public class LineFollower {
+
+	public static void main(String[] aArg) throws Exception {
+		String left = "Turn left ";
+		String right = "Turn right";
+
+		LightSensor light = new LightSensor(SensorPort.S3);
+		final int blackWhiteThreshold = 45;		// 26 if "floodlight" is false.
+		final int sampleInterval = 10; // ms
+
+		final int forward = 1;
+		final int stop = 3;
+		final int flt = 4;
+		final int power = 80;
+
+		// Use the light sensor as a reflection sensor
+		light.setFloodlight(true);
+		LCD.drawString("Light %: ", 0, 0);
+
+		// Show light percent until LEFT is pressed
+		LCD.drawString("Press LEFT", 0, 2);
+		LCD.drawString("to start", 0, 3);
+		while (!Button.LEFT.isDown()) {
+			LCD.drawInt(light.readValue(), 3, 9, 0);
+		}
+
+		// Follow line until ESCAPE is pressed
+		LCD.drawString("Press ESCAPE", 0, 2);
+		LCD.drawString("to stop ", 0, 3);
+		while (!Button.ESCAPE.isDown()) {
+
+			if (light.readValue() > blackWhiteThreshold) {
+				// On white, turn right
+				LCD.drawString(right, 0, 1);
+				MotorPort.B.controlMotor(0, stop);
+				MotorPort.C.controlMotor(power, forward);
+			} else {
+				// On black, turn left
+				LCD.drawString(left, 0, 1);
+				MotorPort.B.controlMotor(power, forward);
+				MotorPort.C.controlMotor(0, stop);
+			}
+			LCD.drawInt(light.readValue(), 3, 9, 0);
+
+			Thread.sleep(sampleInterval);
+
+		}
+
+		// Stop car gently with free wheel drive
+		MotorPort.B.controlMotor(0, flt);
+		MotorPort.C.controlMotor(0, flt);
+		LCD.clear();
+		LCD.drawString("Program stopped", 0, 0);
+		Thread.sleep(2000);
+	}
+}

Lesson 1 - Exercise 4 - SLineFollower/.classpath

+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="con" path="org.lejos.nxt.ldt.LEJOS_LIBRARY_CONTAINER/nxt"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>

Lesson 1 - Exercise 4 - SLineFollower/.project

+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>Lesson 1 - Exercise 4 - SLineFollower</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.lejos.nxt.ldt.leJOSBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.lejos.nxt.ldt.leJOSNature</nature>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>

Lesson 1 - Exercise 4 - SLineFollower/src/DataLogger.java

+import lejos.nxt.*;
+import java.io.*;
+
+/**
+ * A simple data logger that can be used to sample a sequence of integer data
+ * values in a flash file. The file is a text consisting of a sequence of lines
+ * with a time value and a sample data value separated by a comma.
+ * 
+ * When data has been sampled the flash file can be transfered to a PC by means
+ * of the tool nxjbrowse.
+ * 
+ * @author Ole Caprani
+ * @version 4.02.13
+ */
+public class DataLogger {
+	private File f;
+	private FileOutputStream fos;
+	private int startTime;
+
+	public DataLogger(String fileName) {
+		try {
+			f = new File(fileName);
+			if (!f.exists()) {
+				f.createNewFile();
+			} else {
+				f.delete();
+				f.createNewFile();
+			}
+
+			fos = new FileOutputStream(f);
+		} catch (IOException e) {
+			LCD.drawString(e.getMessage(), 0, 0);
+			System.exit(0);
+		}
+		startTime = (int) System.currentTimeMillis();
+	}
+
+	public void start() {
+		startTime = (int) System.currentTimeMillis();
+	}
+
+	public void writeSample(int time, int sample) {
+
+		try {
+			Integer timeInt = new Integer(time);
+			String timeString = timeInt.toString();
+
+			Integer sampleInt = new Integer(sample);
+			String sampleString = sampleInt.toString();
+
+			for (int i = 0; i < timeString.length(); i++) {
+				fos.write((byte) timeString.charAt(i));
+			}
+
+			// Separate items with comma
+			fos.write((byte) (','));
+
+			for (int i = 0; i < sampleString.length(); i++) {
+				fos.write((byte) sampleString.charAt(i));
+			}
+
+			// New line
+			fos.write((byte) ('\r'));
+			fos.write((byte) ('\n'));
+
+		} catch (IOException e) {
+			LCD.drawString(e.getMessage(), 0, 0);
+			System.exit(0);
+		}
+	}
+
+	public void writeSample(int sample) {
+		writeSample((int) System.currentTimeMillis() - startTime, sample);
+	}
+
+	public void close() {
+		try {
+			fos.close();
+		} catch (IOException e) {
+			LCD.drawString(e.getMessage(), 0, 0);
+			System.exit(0);
+		}
+	}
+}

Lesson 1 - Exercise 4 - SLineFollower/src/SLineFollower.java

+import lejos.nxt.*;
+
+/**
+ * A simple line follower for the LEGO 9797 car with a single light sensor.
+ * 
+ * The light sensor should be connected to port 3. The left motor should be
+ * connected to port C and the right motor to port B.
+ * 
+ * Variables initialized with a constant string are used in the LCD.drawString
+ * calls of the control loop to avoid garbage collection.
+ * 
+ * @author Ole Caprani
+ * @version 4.02.13
+ */
+public class SLineFollower {
+
+	public static void main(String[] aArg) throws Exception {
+		String left = "Turn left ";
+		String right = "Turn right";
+
+		LightSensor light = new LightSensor(SensorPort.S3);
+		final int blackWhiteThreshold = 45;
+		final int sampleInterval = 75; // ms
+
+		DataLogger dl = new DataLogger("Sample_75.txt");
+		int lightValue;
+
+		final int forward = 1;
+		final int stop = 3;
+		final int flt = 4;
+		final int power = 80;
+
+		// Use the light sensor as a reflection sensor
+		light.setFloodlight(true);
+		LCD.drawString("Light %: ", 0, 0);
+
+		// Show light percent until LEFT is pressed
+		LCD.drawString("Press LEFT", 0, 2);
+		LCD.drawString("to start", 0, 3);
+		while (!Button.LEFT.isDown()) {
+			LCD.drawInt(light.readValue(), 3, 9, 0);
+		}
+
+		// Follow line until ESCAPE is pressed
+		LCD.drawString("Press ESCAPE", 0, 2);
+		LCD.drawString("to stop ", 0, 3);
+
+		// Start datalogging
+		dl.start();
+		while (!Button.ESCAPE.isDown()) {
+
+			lightValue = light.readValue();
+			if (lightValue > blackWhiteThreshold) {
+				// On white, turn right
+				LCD.drawString(right, 0, 1);
+				MotorPort.B.controlMotor(0, stop);
+				MotorPort.C.controlMotor(power, forward);
+			} else {
+				// On black, turn left
+				LCD.drawString(left, 0, 1);
+				MotorPort.B.controlMotor(power, forward);
+				MotorPort.C.controlMotor(0, stop);
+			}
+			LCD.drawInt(lightValue, 3, 9, 0);
+			dl.writeSample(lightValue);
+			Thread.sleep(sampleInterval);
+
+		}
+
+		// Stop car gently with free wheel drive
+		MotorPort.B.controlMotor(0, flt);
+		MotorPort.C.controlMotor(0, flt);
+		LCD.clear();
+		// Close datalogger
+		dl.close();
+		LCD.drawString("Program stopped", 0, 0);
+		Thread.sleep(2000);
+	}
+}

Lesson 1 - Exercise 5 - SensorPortTest/.classpath

+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="con" path="org.lejos.nxt.ldt.LEJOS_LIBRARY_CONTAINER/nxt"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>

Lesson 1 - Exercise 5 - SensorPortTest/.project

+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>Lesson 1 - Exercise 5 - SensorPortTest</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.lejos.nxt.ldt.leJOSBuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.lejos.nxt.ldt.leJOSNature</nature>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>