com.phidgets
Class EncoderPhidget

java.lang.Object
  com.phidgets.Phidget
      com.phidgets.EncoderPhidget

public final class EncoderPhidget
extends Phidget

This class represents a Phidget Encoder. All methods to read encoder data from an encoder are implemented in this class.

Phidget Encoder boards generally support 1 or more encoders with 0 or more digital inputs. Both high speed optical and low speed mechanical encoders are supported with this API.

Constructor Summary

EncoderPhidget()

Method Summary

void	addEncoderPositionChangeListener(EncoderPositionChangeListener l) Adds a position change listener.
void	addInputChangeListener(InputChangeListener l) Adds an input change listener.
int	getEncoderCount() Returns number of encoders.
int	getEncoderPosition(int index) Returns the position of an encoder.
int	getInputCount() Returns number of digital inputs.
boolean	getInputState(int index) Returns the state of a digital input.
void	removeEncoderPositionChangeListener(EncoderPositionChangeListener l)
void	removeInputChangeListener(InputChangeListener l)
void	setEncoderPosition(int index, int position) Sets the position of a specific encoder.

Methods inherited from class com.phidgets.Phidget

addAttachListener, addDetachListener, addErrorListener, close, equals, getDeviceName, getDeviceType, getDeviceVersion, getLibraryVersion, getSerialNumber, getTag, isAttached, open, openAny, removeAttachListener, removeDetachListener, removeErrorListener, setTag, toString, waitForAttachment

Methods inherited from class java.lang.Object

getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

EncoderPhidget

public EncoderPhidget()
               throws PhidgetException

Throws:

PhidgetException

Method Detail

getEncoderCount

public int getEncoderCount()
                    throws PhidgetException

Returns number of encoders. All current encoder boards support one encoder.

Returns:

number of encoders

Throws:

PhidgetException - If this Phidget is not opened and attached. See open for information on determining if a device is attached.

getInputCount

public int getInputCount()
                  throws PhidgetException

Returns number of digital inputs. On the mechanical encoder this refers to the pushbutton. The high speed encoder does not have any digital inputs.

Returns:

number of inputs

Throws:

PhidgetException - If this Phidget is not opened and attached. See open for information on determining if a device is attached.

getEncoderPosition

public int getEncoderPosition(int index)
                       throws PhidgetException

Returns the position of an encoder. This is an absolute position as calcutated since the encoder was plugged in. This value can be reset to anything using setEncoderPosition.

Parameters:

index - index of the encoder

Returns:

position of the encoder

Throws:

PhidgetException - If this Phidget is not opened and attached, or if the index is out of range. See open for information on determining if a device is attached.

setEncoderPosition

public void setEncoderPosition(int index,
                               int position)
                        throws PhidgetException

Sets the position of a specific encoder. This resets the internal position count for an encoder. This call in no way actually sends information to the device, as an absolute position is maintained only in the library. After this call, position changes from the encoder will use the new value to calculate absolute position as reported by getEncoderPosition.

Parameters:

index - index of the encoder

position - new position for this encoder.

Throws:

PhidgetException - If this Phidget is not opened and attached, or if the index is out of range. See open for information on determining if a device is attached.

getInputState

public boolean getInputState(int index)
                      throws PhidgetException

Returns the state of a digital input. On the mechanical encoder this refers to the pushbutton. The high speed encoder does not have any digital inputs. A value of true means that the input is active(the button is pushed).

Parameters:

index - index of the input

Returns:

state of the input

Throws:

PhidgetException - If this Phidget is not opened and attached, or if the index is out of range. See open for information on determining if a device is attached.

addEncoderPositionChangeListener

public final void addEncoderPositionChangeListener(EncoderPositionChangeListener l)

Adds a position change listener. The position change handler is a method that will be called when the position of an encoder changes. The position change event provides data about how many ticks have occured, and how much time has passed since the last position change event, but does not contain an absolute position. This can be obtained from getEncoderPosition.

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

Parameters:

l - An implemetation of the EncoderPositionChangeListener interface

removeEncoderPositionChangeListener

public final void removeEncoderPositionChangeListener(EncoderPositionChangeListener l)

addInputChangeListener

public final void addInputChangeListener(InputChangeListener l)

Adds an input change listener. The input change handler is a method that will be called when an input on this Encoder board has changed.

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

Parameters:

l - An implemetation of the InputChangeListener interface

removeInputChangeListener

public final void removeInputChangeListener(InputChangeListener l)