From 0b624384cd52be20e61284551d832b499d7b7707 Mon Sep 17 00:00:00 2001 From: Jonathan McCrohan Date: Sat, 14 Apr 2012 12:56:48 +0100 Subject: Imported Upstream version 2.1.8.20120216 --- Java/com/phidgets/AdvancedServoPhidget.java | 492 ++++++++++++++++++++++++++++ 1 file changed, 492 insertions(+) create mode 100644 Java/com/phidgets/AdvancedServoPhidget.java (limited to 'Java/com/phidgets/AdvancedServoPhidget.java') diff --git a/Java/com/phidgets/AdvancedServoPhidget.java b/Java/com/phidgets/AdvancedServoPhidget.java new file mode 100644 index 0000000..1aa485a --- /dev/null +++ b/Java/com/phidgets/AdvancedServoPhidget.java @@ -0,0 +1,492 @@ + +/* + * Copyright 2006 Phidgets Inc. All rights reserved. + */ + +package com.phidgets; +import java.util.Iterator; +import java.util.LinkedList; +import com.phidgets.event.*; +/** + * This class represents a Phidget Advanced Servo Controller. All methods + * to to control a motor controller and read back motor data are implemented in this class. + *

+ * The Phidget Advanced Servo Controller is able to control 1 or more servo motors. Motos acceleration + * and Velocity are controllable. The number of servos that can be controlled depends on the + * version of the controller. + * + * @author Phidgets Inc. + */ +public final class AdvancedServoPhidget extends Phidget +{ + public AdvancedServoPhidget () throws PhidgetException + { + super (create ()); + } + private static native long create () throws PhidgetException; + + /** + * Default - This is what the servo API been historically used, originally based on the Futaba FP-S148. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_DEFAULT = 1; + /** + * Raw us mode - all position, velocity, acceleration functions are specified in microseconds rather then degrees. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_RAW_us_MODE = 2; + /** + * HiTec HS-322HD Standard Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_HITEC_HS322HD = 3; + /** + * HiTec HS-5245MG Digital Mini Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_HITEC_HS5245MG = 4; + /** + * HiTec HS-805BB Mega Quarter Scale Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_HITEC_805BB = 5; + /** + * HiTec HS-422 Standard Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_HITEC_HS422 = 6; + /** + * Tower Pro MG90 Micro Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_TOWERPRO_MG90 = 7; + /** + * HiTec HSR-1425CR Continuous Rotation Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_HITEC_HSR1425CR = 8; + /** + * HiTec HS-785HB Sail Winch Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_HITEC_HS785HB = 9; + /** + * HiTec HS-485HB Deluxe Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_HITEC_HS485HB = 10; + /** + * HiTec HS-645MG Ultra Torque Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_HITEC_HS645MG = 11; + /** + * HiTec HS-815BB Mega Sail Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_HITEC_815BB = 12; + /** + * Firgelli L12 Linear Actuator 30mm 50:1. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_FIRGELLI_L12_30_50_06_R = 13; + /** + * Firgelli L12 Linear Actuator 50mm 100:1. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_FIRGELLI_L12_50_100_06_R = 14; + /** + * Firgelli L12 Linear Actuator 50mm 210:1. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_FIRGELLI_L12_50_210_06_R = 15; + /** + * Firgelli L12 Linear Actuator 100mm 50:1. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_FIRGELLI_L12_100_50_06_R = 16; + /** + * Firgelli L12 Linear Actuator 100mm 100:1. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_FIRGELLI_L12_100_100_06_R = 17; + /** + * SpringRC SM-S2313M Micro Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_SPRINGRC_SM_S2313M = 18; + /** + * SpringRC SM-S3317M Small Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_SPRINGRC_SM_S3317M = 19; + /** + * SpringRC SM-S3317SR Small Continuous Rotation Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_SPRINGRC_SM_S3317SR = 20; + /** + * SpringRC SM-S4303R Standard Continuous Rotation Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_SPRINGRC_SM_S4303R = 21; + /** + * SpringRC SM-S4315M High Torque Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_SPRINGRC_SM_S4315M = 22; + /** + * SpringRC SM-S4315R High Torque Continuous Rotation Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_SPRINGRC_SM_S4315R = 23; + /** + * SpringRC SM-S4505B Standard Servo. This is used with {@link #getServoType getServoType} and {@link #setServoType setServoType} + */ + public static final int PHIDGET_SERVO_SPRINGRC_SM_S4505B = 24; + /** + * User Defined servo parameters. This is used with {@link #getServoType getServoType} + */ + public static final int PHIDGET_SERVO_USER_DEFINED = 25; + + /** + * Returns the number of servo motors supported by this Phidget. This does not neccesarily correspond + * to the number of motors actually attached to the board. + * @return number of supported motors + * @throws PhidgetException If this Phidget is not opened and attached. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native int getMotorCount () throws PhidgetException; + /** + * Returns the maximum acceleration that a motor will accept, or return. + *

This value is in degrees per second squared. + * @param index Index of the motor + * @return Maximum acceleration + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getAccelerationMax (int index) throws PhidgetException; + /** + * Returns the minimum acceleration that a motor will accept, or return. + *

This value is in degrees per second squared. + * @param index Index of the motor + * @return Minimum acceleration + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getAccelerationMin (int index) throws PhidgetException; + /** + * Returns the maximum velocity that a servo motor will accept, or return. + *

This value is in degrees per second. + * @param index Index of the motor + * @return Maximum velocity + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getVelocityMax (int index) throws PhidgetException; + /** + * Returns the minimum velocity that a servo motor will accept, or return. + *

This value is in degrees per second. + * @param index Index of the motor + * @return Minimum velocity + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getVelocityMin (int index) throws PhidgetException; + /** + * Returns the maximum position that a servo motor will accept, or return. + *

This value is in degrees. + * @param index Index of the motor + * @return Maximum position + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getPositionMax (int index) throws PhidgetException; + /** + * Sets the maximum position that a servo motor will accept, or return. This is for limiting the range of motion of the servo + * controller. The Maximum cannot be extended beyond it's original value. + *

This value is in degrees. + * @param index Index of the motor + * @param position Maximum position + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native void setPositionMax (int index, double position) throws PhidgetException; + /** + * Returns the minimum position that a servo motor will accept, or return. + *

This value uses the same units as + *

This value is in degrees. + * @param index Index of the motor + * @return Minimum position + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getPositionMin (int index) throws PhidgetException; + /** + * Sets the minimum position that a servo motor will accept, or return. This is for limiting the range of motion of the servo + * controller. The Minimum cannot be extended beyond it's original value. + *

This value is in degrees. + * @param index Index of the motor + * @param position Minimum position + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native void setPositionMin (int index, double position) throws PhidgetException; + /** + * Returns a motor's acceleration. The valid range is between {@link #getAccelerationMin getAccelerationMin} + * and {@link #getAccelerationMax getAccelerationMax}, and refers to how fast the Servo Controller will change the speed of a motor. + *

This value is in degrees per second squared. + * @param index index of motor + * @return acceleration of motor + * @throws PhidgetException If this Phidget is not opened and attached, if the index is invalid, or if the acceleration is unknown. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getAcceleration (int index) throws PhidgetException; + /** + * Sets a motor's acceleration. + * The valid range is between {@link #getAccelerationMin getAccelerationMin} and {@link #getAccelerationMax getAccelerationMax}. + * This controls how fast the motor changes speed. + *

This value is in degrees per second squared. + * @param index index of the motor + * @param acceleration requested acceleration for that motor + * @throws PhidgetException If this Phidget is not opened and attached, or if the index or acceleration are invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native void setAcceleration (int index, double acceleration) throws PhidgetException; + /** + * Returns a motor's velocity limit. This is the maximum velocity that the motor will turn at. + * The valid range is between {@link #getVelocityMin getVelocityMin} and {@link #getVelocityMax getVelocityMax}, + * with 0 being stopped. + *

This value is in degrees per second. + * @param index index of the motor + * @return current speed of the motor + * @throws PhidgetException If this Phidget is not opened and attached, if the index is invalid, or if the velocity in unknown. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getVelocityLimit (int index) throws PhidgetException; + /** + * Sets a motor's velocity limit. This is the maximum velocity that the motor will turn at. + * The valid range is between {@link #getVelocityMin getVelocityMin} and {@link #getVelocityMax getVelocityMax}, + * with 0 being stopped. + *

This value is in degrees per second. + * @param index index of the motor + * @param velocity requested velocity for the motor + * @throws PhidgetException If this Phidget is not opened and attached, or if the index or velocity are invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native void setVelocityLimit (int index, double velocity) throws PhidgetException; + /** + * Returns a motor's current velocity. The valid range is between {@link #getVelocityMin getVelocityMin} and {@link #getVelocityMax getVelocityMax}, + * with 0 being stopped. + *

This value is in degrees per second. + * @param index index of the motor + * @return current speed of the motor + * @throws PhidgetException If this Phidget is not opened and attached, if the index is invalid, or if the velocity in unknown. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getVelocity (int index) throws PhidgetException; + /** + * Returns a motor's current position. This is the actual position that the motor is at right now. + * The valid range is between {@link #getPositionMin getPositionMin} and {@link #getPositionMax getPositionMax}. + *

This value is in degrees. + * @param index index of the motor + * @return current position of the motor + * @throws PhidgetException If this Phidget is not opened and attached, if the index is invalid, or if the position in unknown. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getPosition (int index) throws PhidgetException; + /** + * Sets a motor's target position. Use this is set the target position for the servo. + * If the servo is {@link #setEngaged engaged} it will start moving towards this target position. + * The valid range is between {@link #getPositionMin getPositionMin} and {@link #getPositionMax getPositionMax}. + *

This value is in degrees. + * @param index index of the motor + * @param position target position of the motor + * @throws PhidgetException If this Phidget is not opened and attached, or if the index or position are invalid. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native void setPosition (int index, double position) throws PhidgetException; + /** + * Returns the engaged state of a motor. + * + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is out of range. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native boolean getEngaged (int index) throws PhidgetException; + /** + * Engage or disengage a motor. + *

+ * This engages or disengages the servo motor. The motors are by default disengaged when the servo controller is plugged in. + * When the servo is disengaged, position, velocity, etc. can all be set, but the motor will not start moving until it is engaged. + * If position is read when a motor is disengaged, it will throw an exception. + *

+ * This corresponds to a PCM of 0 being sent to the servo. + * + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is out of range. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native void setEngaged (int index, boolean state) throws PhidgetException; + /** + * Returns the speed ramping state of a motor. + * + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is out of range. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native boolean getSpeedRampingOn (int index) throws PhidgetException; + /** + * Sets the speed ramping state. + *

+ * Disable speed ramping to disable velocity and acceleration control. With speed ramping disabled, the servo will be sent to + * the desired position immediately upon recieving the command. This is how the regular Phidget Servo Controller works. + *

+ * This is turned on by default. + * + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is out of range. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native void setSpeedRampingOn (int index, boolean state) throws PhidgetException; + /** + * Returns a motor's current usage. The valid range depends on the servo controller. + * This value is in Amps. + * @param index index of the motor + * @return current usage of the motor + * @throws PhidgetException If this Phidget is not opened and attached, if the index is invalid, or if the value is unknown. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native double getCurrent (int index) throws PhidgetException; + /** + * Returns the stopped state of a motor. Use this to determine if the motor is moving and/or up to date with the latest commands you have sent. + * If this is true, the motor is guaranteed to be stopped and to have processed every command issued. Generally, this would + * be polled after a target position is set to wait until that position is reached. + * + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is out of range. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native boolean getStopped (int index) throws PhidgetException; + /** + * Returns the servo type for an index. + * The possible values for type are {@link #PHIDGET_SERVO_DEFAULT PHIDGET_SERVO_DEFAULT}, + * {@link #PHIDGET_SERVO_RAW_us_MODE PHIDGET_SERVO_RAW_us_MODE}, {@link #PHIDGET_SERVO_HITEC_HS322HD PHIDGET_SERVO_HITEC_HS322HD}, + * {@link #PHIDGET_SERVO_HITEC_HS5245MG PHIDGET_SERVO_HITEC_HS5245MG}, {@link #PHIDGET_SERVO_HITEC_805BB PHIDGET_SERVO_HITEC_805BB}, + * {@link #PHIDGET_SERVO_HITEC_HS422 PHIDGET_SERVO_HITEC_HS422}, etc. + * @param index Input + * @return Servo Type + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is out of range. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native int getServoType (int index) throws PhidgetException; + /** + * Sets the servo type for an index. + *

+ * This constrains the PCM to the valid range of the servo, and sets the degrees-to-PCM ratio to match the actual servo rotation. + * Velocity is also constrained to the maximum speed attainable by the servo. + *

+ * The possible values for type are {@link #PHIDGET_SERVO_DEFAULT PHIDGET_SERVO_DEFAULT}, + * {@link #PHIDGET_SERVO_RAW_us_MODE PHIDGET_SERVO_RAW_us_MODE}, {@link #PHIDGET_SERVO_HITEC_HS322HD PHIDGET_SERVO_HITEC_HS322HD}, + * {@link #PHIDGET_SERVO_HITEC_HS5245MG PHIDGET_SERVO_HITEC_HS5245MG}, {@link #PHIDGET_SERVO_HITEC_805BB PHIDGET_SERVO_HITEC_805BB}, + * {@link #PHIDGET_SERVO_HITEC_HS422 PHIDGET_SERVO_HITEC_HS422}, etc. + *

+ * Support for other servo types can be achieved by using {@link #setServoParameters setServoParameters}. + *

+ * The default setting is {@link #PHIDGET_SERVO_DEFAULT PHIDGET_SERVO_DEFAULT}, which is used for historical (backwards compatibility) reasons. + * @param index Input + * @param type Servo Type + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is out of range. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native void setServoType (int index, int type) throws PhidgetException; + /** + * Sets the servo parameters for a custom servo definition. + *

+ * This constrains the PCM to the valid range of the servo, and sets the degrees-to-PCM ratio to match the actual servo rotation. + * Velocity is also constrained to the maximum speed attainable by the servo. + *

+ * @param index Servo Index + * @param minUs Minimum PCM supported in microseconds + * @param maxUs Maximum PCM supported in microseconds + * @param degrees Degrees of rotation represented by the given PCM range + * @param velocityMax Maximum supported velocity of the servo in degrees/second + * @throws PhidgetException If this Phidget is not opened and attached, or if the index is out of range. + * See {@link com.phidgets.Phidget#open(int) open} for information on determining if a device is attached. + */ + public native void setServoParameters (int index, double minUs, double maxUs, double degrees, double velocityMax) throws PhidgetException; + + private final void enableDeviceSpecificEvents (boolean b) + { + enableServoPositionChangeEvents (b && servoPositionChangeListeners.size () > 0); + enableServoVelocityChangeEvents (b && servoVelocityChangeListeners.size () > 0); + enableCurrentChangeEvents (b && currentChangeListeners.size () > 0); + } + /** + * Adds a position change listener. The position change handler is a method that will be called when the servo + * position has changed. + *

+ * There is no limit on the number of position change handlers that can be registered for a particular Phidget. + * + * @param l An implemetation of the {@link com.phidgets.event.ServoPositionChangeListener ServoPositionChangeListener} interface + */ + public final void addServoPositionChangeListener (ServoPositionChangeListener l) + { + synchronized (servoPositionChangeListeners) + { + servoPositionChangeListeners.add (l); + enableServoPositionChangeEvents (true); + }} private LinkedList servoPositionChangeListeners = new LinkedList (); + private long nativeServoPositionChangeHandler = 0; + public final void removeServoPositionChangeListener (ServoPositionChangeListener l) + { + synchronized (servoPositionChangeListeners) + { + servoPositionChangeListeners.remove (l); + enableServoPositionChangeEvents (servoPositionChangeListeners.size () > 0); + }} private void fireServoPositionChange (ServoPositionChangeEvent e) + { + synchronized (servoPositionChangeListeners) + { + for (Iterator it = servoPositionChangeListeners.iterator (); it.hasNext ();) + ((ServoPositionChangeListener) it.next ()).servoPositionChanged (e); + } + } + private native void enableServoPositionChangeEvents (boolean b); + /** + * Adds a velocity change listener. The velocity change handler is a method that will be called when the servo + * velocity has changed. + *

+ * There is no limit on the number of velocity change handlers that can be registered for a particular Phidget. + * + * @param l An implemetation of the {@link com.phidgets.event.ServoVelocityChangeListener ServoVelocityChangeListener} interface + */ + public final void addServoVelocityChangeListener (ServoVelocityChangeListener l) + { + synchronized (servoVelocityChangeListeners) + { + servoVelocityChangeListeners.add (l); + enableServoVelocityChangeEvents (true); + }} private LinkedList servoVelocityChangeListeners = new LinkedList (); + private long nativeServoVelocityChangeHandler = 0; + public final void removeServoVelocityChangeListener (ServoVelocityChangeListener l) + { + synchronized (servoVelocityChangeListeners) + { + servoVelocityChangeListeners.remove (l); + enableServoVelocityChangeEvents (servoVelocityChangeListeners.size () > 0); + }} private void fireServoVelocityChange (ServoVelocityChangeEvent e) + { + synchronized (servoVelocityChangeListeners) + { + for (Iterator it = servoVelocityChangeListeners.iterator (); it.hasNext ();) + ((ServoVelocityChangeListener) it.next ()).servoVelocityChanged (e); + } + } + private native void enableServoVelocityChangeEvents (boolean b); + /** + * Adds a current change listener. The current change handler is a method that will be called when the servo + * current has changed. + *

+ * There is no limit on the number of current change handlers that can be registered for a particular Phidget. + *

+ * Note that not all stepper controllers support current sensing. + * + * @param l An implemetation of the {@link com.phidgets.event.CurrentChangeListener CurrentChangeListener} interface + */ + public final void addCurrentChangeListener (CurrentChangeListener l) + { + synchronized (currentChangeListeners) + { + currentChangeListeners.add (l); + enableCurrentChangeEvents (true); + }} private LinkedList currentChangeListeners = new LinkedList (); + private long nativeCurrentChangeHandler = 0; + public final void removeCurrentChangeListener (CurrentChangeListener l) + { + synchronized (currentChangeListeners) + { + currentChangeListeners.remove (l); + enableCurrentChangeEvents (currentChangeListeners.size () > 0); + }} private void fireCurrentChange (CurrentChangeEvent e) + { + synchronized (currentChangeListeners) + { + for (Iterator it = currentChangeListeners.iterator (); it.hasNext ();) + ((CurrentChangeListener) it.next ()).currentChanged (e); + } + } + private native void enableCurrentChangeEvents (boolean b); +} -- cgit v1.2.3