Merge "Added C++ Encoder samples to Eclipse Plugin."

eclipse-plugins/edu.wpi.first.wpilib.plugins.cpp/resources/templates/examples/Encoder/src/Robot.cpp

@@ -0,0 +1,82 @@
+#include "WPILib.h"
+
+/**
+ * Sample program displaying the value of a quadrature encoder on the SmartDashboard.
+ * Quadrature Encoders are digital sensors which can detect the amount the encoder
+ *   has rotated since starting as well as the direction in which the encoder
+ *   shaft is rotating. However, encoders can not tell you the absolute
+ *   position of the encoder shaft (ie, it considers where it starts to be the
+ *   zero position, no matter where it starts), and so can only tell you how
+ *   much the encoder has rotated since starting.
+ * Depending on the precision of an encoder, it will have fewer or greater
+ *   ticks per revolution; the number of ticks per revolution will affect the
+ *   conversion between ticks and distance, as specified by DistancePerPulse.
+ * One of the most common uses of encoders is in the drivetrain, so that the
+ *   distance that the robot drives can be precisely controlled during the
+ *   autonomous mode.
+ */
+class Robot: public SampleRobot
+{
+	Encoder m_encoder;
+
+	/**
+	 * Time to wait between updating SmartDashboard values.
+	 * It is generally a good idea to stick a short wait in these loops
+	 *   to avoid hogging CPU power, especially as there will be no
+	 *   perceivable difference in the SmartDashboard display.
+	 */
+	const double kUpdatePeriod = 0.005; // 5milliseconds / 0.005 seconds.
+
+public:
+	/**
+	 * The Encoder object is constructed with 4 parameters, the last two being optional.
+	 * The first two parameters (1, 2 in this case) refer to the ports on the
+	 *   roboRIO which the encoder uses. Because a quadrature encoder has
+	 *   two signal wires, the signal from two DIO ports on the roboRIO are used.
+	 * The third (optional) parameter is a boolean which defaults to false.
+	 *   If you set this parameter to true, the direction of the encoder will
+	 *   be reversed, in case it makes more sense mechanically.
+	 * The final (optional) parameter specifies encoding rate (k1X, k2X, or k4X)
+	 *   and defaults to k4X. Faster (k4X) encoding gives greater positional
+	 *   precision but more noise in the rate.
+	 */
+	Robot() : m_encoder(1, 2, false, Encoder::k4X)
+	{
+		// Defines the number of samples to average when determining the rate.
+		// On a quadrature encoder, values range from 1-255; larger values
+		//   result in smoother but potentially less accurate rates than lower values.
+		m_encoder.SetSamplesToAverage(5);
+
+		// Defines how far the mechanism attached to the encoder moves per pulse.
+		// In this case, we assume that a 360 count encoder is directly attached
+		//   to a 3 inch diameter (1.5inch radius) wheel, and that we want to
+		//   measure distance in inches.
+		m_encoder.SetDistancePerPulse(1.0 / 360.0 * 2.0 * 3.1415 * 1.5);
+
+		// Defines the lowest rate at which the encoder will not be considered
+		//   stopped, for the purposes of the GetStopped() method.
+		// Units are in distance / second, where distance refers to the units
+		//   of distance that you are using, in this case inches.
+		m_encoder.SetMinRate(1.0);
+	}
+
+	/**
+	 * Retrieve various information from the encoder and display it
+	 *   on the SmartDashboard.
+	 */
+	void OperatorControl()
+	{
+		while (IsOperatorControl())
+		{
+			// Retrieve the net displacement of the Encoder since the lsat Reset.
+			SmartDashboard::PutNumber("Encoder Distance", m_encoder.GetDistance());
+
+			// Retrieve the current rate of the encoder.
+			SmartDashboard::PutNumber("Encoder Rate", m_encoder.GetRate());
+
+			Wait(kUpdatePeriod); // Wait a short bit before updating again.
+		}
+	}
+};
+
+START_ROBOT_CLASS(Robot);

eclipse-plugins/edu.wpi.first.wpilib.plugins.cpp/resources/templates/examples/MotorControlEncoder/src/Robot.cpp

@@ -0,0 +1,55 @@
+#include "WPILib.h"
+
+/**
+ * This sample program shows how to control a motor using a joystick. In the operator
+ * control part of the program, the joystick is read and the value is written to the motor.
+ * An Encoder is then used to read the total distance that the motor has turned and
+ *   to display it on the SmartDashboard.
+ *
+ * Joystick analog values range from -1 to 1 and speed controller inputs as range from
+ * -1 to 1 making it easy to work together. The program also delays a short time in the loop
+ * to allow other threads to run. This is generally a good idea, especially since the joystick
+ * values are only transmitted from the Driver Station once every 20ms.
+ */
+class Robot : public SampleRobot {
+	Joystick m_stick;
+
+	// The motor to control with the Joystick.
+	// This uses a Talon speed controller; use the Victor or Jaguar classes for
+	//   other speed controllers.
+	Talon m_motor;
+
+	// update every 0.005 seconds/5 milliseconds.
+	double kUpdatePeriod = 0.005;
+
+	Encoder m_encoder;
+
+public:
+	Robot() :
+			m_stick(0), // Initialize Joystick on port 0.
+			m_motor(2), // Initialize the Talon on channel 0.
+			m_encoder(1, 2) // Iniitialize encoder connected on DIO ports 1 and 2.
+	{
+		// Distance will give total rotations of the motor, assuming a 360 count encoder.
+		m_encoder.SetDistancePerPulse(1.0 / 360.0);
+	}
+
+	/**
+	 * Runs the motor from the output of a Joystick.
+	 * Simultaneously displays encoder values on the SmartDashboard.
+	 */
+	void OperatorControl() {
+		while (IsOperatorControl()) {
+			// Set the motor controller's output.
+			// This takes a number from -1 (100% speed in reverse) to +1 (100% speed forwards).
+			m_motor.Set(m_stick.GetY());
+
+			// Display the total displacement of the encoder, in rotations.
+			SmartDashboard::PutNumber("Encoder Distance", m_encoder.GetDistance());
+
+			Wait(kUpdatePeriod); // Wait 5ms for the next update.
+		}
+	}
+};
+
+START_ROBOT_CLASS(Robot);

eclipse-plugins/edu.wpi.first.wpilib.plugins.cpp/resources/templates/examples/examples.xml

@@ -104,6 +104,25 @@
   </files>
 </example>
 
+<example>
+  <name>Motor Control With Encoder</name>
+  <description>Demonstrate controlling a single motor with a Joystick and displaying the net movement of the motor using an encoder.</description>
+  <tags>
+    <tag>Robot and Motor</tag>
+    <tag>Digital</tag>
+    <tag>Sensors</tag>
+    <tag>Actuators</tag>
+    <tag>Joystick</tag>
+    <tag>Complete List</tag>
+  </tags>
+  <packages>
+    <package>src</package>
+  </packages>
+  <files>
+    <file source="examples/MotorControl/src/Robot.cpp" destination="src/Robot.cpp"></file>
+  </files>
+</example>
+
 <example>
   <name>Relay</name>
   <description>Demonstrate controlling a Relay from Joystick buttons.</description>
@@ -153,6 +172,22 @@
   </files>
 </example>
 
+<example>
+  <name>Encoder</name>
+  <description>Demonstrate displaying the value of a quadrature encoder on the SmartDashboard.</description>
+  <tags>
+    <tag>Complete List</tag>
+    <tag>Digital</tag>
+    <tag>Sensors</tag>
+  </tags>
+  <packages>
+    <package>src</package>
+  </packages>
+  <files>
+    <file source="examples/Encoder/src/Robot.cpp" destination="src/Robot.cpp"></file>
+  </files>
+</example>
+
 <example>
   <name>Arcade Drive</name>
   <description>An example program which the use of Arcade Drive with the RobotDrive class</description>