Java - Rotary Encoder Bricklet¶

Simple¶

Download (ExampleSimple.java)

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import com.tinkerforge.IPConnection;
import com.tinkerforge.BrickletRotaryEncoder;

public class ExampleSimple {
    private static final String HOST = "localhost";
    private static final int PORT = 4223;

    // Change XYZ to the UID of your Rotary Encoder Bricklet
    private static final String UID = "XYZ";

    // Note: To make the example code cleaner we do not handle exceptions. Exceptions
    //       you might normally want to catch are described in the documentation
    public static void main(String args[]) throws Exception {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickletRotaryEncoder re = new BrickletRotaryEncoder(UID, ipcon); // Create device object

        ipcon.connect(HOST, PORT); // Connect to brickd
        // Don't use device before ipcon is connected

        // Get current count without reset
        int count = re.getCount(false); // Can throw com.tinkerforge.TimeoutException
        System.out.println("Count: " + count);

        System.out.println("Press key to exit"); System.in.read();
        ipcon.disconnect();
    }
}

Callback¶

Download (ExampleCallback.java)

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import com.tinkerforge.IPConnection;
import com.tinkerforge.BrickletRotaryEncoder;

public class ExampleCallback {
    private static final String HOST = "localhost";
    private static final int PORT = 4223;

    // Change XYZ to the UID of your Rotary Encoder Bricklet
    private static final String UID = "XYZ";

    // Note: To make the example code cleaner we do not handle exceptions. Exceptions
    //       you might normally want to catch are described in the documentation
    public static void main(String args[]) throws Exception {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickletRotaryEncoder re = new BrickletRotaryEncoder(UID, ipcon); // Create device object

        ipcon.connect(HOST, PORT); // Connect to brickd
        // Don't use device before ipcon is connected

        // Add count listener
        re.addCountListener(new BrickletRotaryEncoder.CountListener() {
            public void count(int count) {
                System.out.println("Count: " + count);
            }
        });

        // Set period for count callback to 0.05s (50ms)
        // Note: The count callback is only called every 0.05 seconds
        //       if the count has changed since the last call!
        re.setCountCallbackPeriod(50);

        System.out.println("Press key to exit"); System.in.read();
        ipcon.disconnect();
    }
}

Basic Functions¶

class BrickletRotaryEncoder(String uid, IPConnection ipcon)¶

Parameters:	uid – Type: String ipcon – Type: IPConnection
Returns:	rotaryEncoder – Type: BrickletRotaryEncoder

Creates an object with the unique device ID uid:

BrickletRotaryEncoder rotaryEncoder = new BrickletRotaryEncoder("YOUR_DEVICE_UID", ipcon);

This object can then be used after the IP Connection is connected.

int BrickletRotaryEncoder.getCount(boolean reset)¶

Parameters:	reset – Type: boolean
Returns:	count – Type: int, Range: [-231 to 231 - 1]

Returns the current count of the encoder. If you set reset to true, the count is set back to 0 directly after the current count is read.

The encoder has 24 steps per rotation

Turning the encoder to the left decrements the counter, so a negative count is possible.

boolean BrickletRotaryEncoder.isPressed()¶

Returns:	pressed – Type: boolean

Returns true if the button is pressed and false otherwise.

It is recommended to use the PressedListener and ReleasedListener listeners to handle the button.

Advanced Functions¶

BrickletRotaryEncoder.Identity BrickletRotaryEncoder.getIdentity()¶

Return Object:

uid – Type: String, Length: up to 8 connectedUid – Type: String, Length: up to 8 position – Type: char, Range: ['a' to 'h', 'z'] hardwareVersion – Type: short[], Length: 3 0: major – Type: short, Range: [0 to 255] 1: minor – Type: short, Range: [0 to 255] 2: revision – Type: short, Range: [0 to 255] firmwareVersion – Type: short[], Length: 3 0: major – Type: short, Range: [0 to 255] 1: minor – Type: short, Range: [0 to 255] 2: revision – Type: short, Range: [0 to 255] deviceIdentifier – Type: int, Range: [0 to 216 - 1]

Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.

The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

Listener Configuration Functions¶

void BrickletRotaryEncoder.setCountCallbackPeriod(long period)¶

Parameters:	period – Type: long, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Sets the period with which the CountListener listener is triggered periodically. A value of 0 turns the listener off.

The CountListener listener is only triggered if the count has changed since the last triggering.

long BrickletRotaryEncoder.getCountCallbackPeriod()¶

Returns:	period – Type: long, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Returns the period as set by setCountCallbackPeriod().

void BrickletRotaryEncoder.setCountCallbackThreshold(char option, int min, int max)¶

Parameters:	option – Type: char, Range: See constants, Default: 'x' min – Type: int, Range: [-231 to 231 - 1], Default: 0 max – Type: int, Range: [-231 to 231 - 1], Default: 0

Sets the thresholds for the CountReachedListener listener.

The following options are possible:

Option	Description
'x'	Listener is turned off
'o'	Listener is triggered when the count is outside the min and max values
'i'	Listener is triggered when the count is inside the min and max values
'<'	Listener is triggered when the count is smaller than the min value (max is ignored)
'>'	Listener is triggered when the count is greater than the min value (max is ignored)

The following constants are available for this function:

For option:

• BrickletRotaryEncoder.THRESHOLD_OPTION_OFF = 'x'
• BrickletRotaryEncoder.THRESHOLD_OPTION_OUTSIDE = 'o'
• BrickletRotaryEncoder.THRESHOLD_OPTION_INSIDE = 'i'
• BrickletRotaryEncoder.THRESHOLD_OPTION_SMALLER = '<'
• BrickletRotaryEncoder.THRESHOLD_OPTION_GREATER = '>'

BrickletRotaryEncoder.CountCallbackThreshold BrickletRotaryEncoder.getCountCallbackThreshold()¶

Return Object:	option – Type: char, Range: See constants, Default: 'x' min – Type: int, Range: [-231 to 231 - 1], Default: 0 max – Type: int, Range: [-231 to 231 - 1], Default: 0

Returns the threshold as set by setCountCallbackThreshold().

The following constants are available for this function:

For option:

• BrickletRotaryEncoder.THRESHOLD_OPTION_OFF = 'x'
• BrickletRotaryEncoder.THRESHOLD_OPTION_OUTSIDE = 'o'
• BrickletRotaryEncoder.THRESHOLD_OPTION_INSIDE = 'i'
• BrickletRotaryEncoder.THRESHOLD_OPTION_SMALLER = '<'
• BrickletRotaryEncoder.THRESHOLD_OPTION_GREATER = '>'

void BrickletRotaryEncoder.setDebouncePeriod(long debounce)¶

Parameters:	debounce – Type: long, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100

Sets the period with which the threshold listener

• CountReachedListener

is triggered, if the thresholds

• setCountCallbackThreshold()

keeps being reached.

long BrickletRotaryEncoder.getDebouncePeriod()¶

Returns:	debounce – Type: long, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100

Returns the debounce period as set by setDebouncePeriod().

Listeners¶

Listeners can be registered to receive time critical or recurring data from the device. The registration is done with add*Listener() functions of the device object.

The parameter is a listener class object, for example:

device.addExampleListener(new BrickletRotaryEncoder.ExampleListener() {
    public void property(int value) {
        System.out.println("Value: " + value);
    }
});

The available listener classes with inherent methods to be overwritten are described below. It is possible to add several listeners and to remove them with the corresponding remove*Listener() function.

class BrickletRotaryEncoder.CountListener()¶

This listener can be added with the addCountListener() function. An added listener can be removed with the removeCountListener() function.

void count(int count)

Parameters:	count – Type: int, Range: [-231 to 231 - 1]

This listener is triggered periodically with the period that is set by setCountCallbackPeriod(). The parameter is the count of the encoder.

The CountListener listener is only triggered if the count has changed since the last triggering.

class BrickletRotaryEncoder.CountReachedListener()¶

This listener can be added with the addCountReachedListener() function. An added listener can be removed with the removeCountReachedListener() function.

void countReached(int count)

Parameters:	count – Type: int, Range: [-231 to 231 - 1]

This listener is triggered when the threshold as set by setCountCallbackThreshold() is reached. The parameter is the count of the encoder.

If the threshold keeps being reached, the listener is triggered periodically with the period as set by setDebouncePeriod().

class BrickletRotaryEncoder.PressedListener()¶

This listener can be added with the addPressedListener() function. An added listener can be removed with the removePressedListener() function.

void pressed()

This listener is triggered when the button is pressed.

class BrickletRotaryEncoder.ReleasedListener()¶

This listener can be added with the addReleasedListener() function. An added listener can be removed with the removeReleasedListener() function.

void released()

This listener is triggered when the button is released.

Virtual Functions¶

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.

short[] BrickletRotaryEncoder.getAPIVersion()¶

Return Object:	apiVersion – Type: short[], Length: 3 0: major – Type: short, Range: [0 to 255] 1: minor – Type: short, Range: [0 to 255] 2: revision – Type: short, Range: [0 to 255]

Returns the version of the API definition implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

boolean BrickletRotaryEncoder.getResponseExpected(byte functionId)¶

Parameters:	functionId – Type: byte, Range: See constants
Returns:	responseExpected – Type: boolean

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For listener configuration functions it is enabled by default too, but can be disabled by setResponseExpected(). For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

• BrickletRotaryEncoder.FUNCTION_SET_COUNT_CALLBACK_PERIOD = 2
• BrickletRotaryEncoder.FUNCTION_SET_COUNT_CALLBACK_THRESHOLD = 4
• BrickletRotaryEncoder.FUNCTION_SET_DEBOUNCE_PERIOD = 6

void BrickletRotaryEncoder.setResponseExpected(byte functionId, boolean responseExpected)¶

Parameters:	functionId – Type: byte, Range: See constants responseExpected – Type: boolean

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and listener configuration functions (default value: true). For getter functions it is always enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

• BrickletRotaryEncoder.FUNCTION_SET_COUNT_CALLBACK_PERIOD = 2
• BrickletRotaryEncoder.FUNCTION_SET_COUNT_CALLBACK_THRESHOLD = 4
• BrickletRotaryEncoder.FUNCTION_SET_DEBOUNCE_PERIOD = 6

void BrickletRotaryEncoder.setResponseExpectedAll(boolean responseExpected)¶

Parameters:	responseExpected – Type: boolean

Changes the response expected flag for all setter and listener configuration functions of this device at once.

Constants¶

int BrickletRotaryEncoder.DEVICE_IDENTIFIER¶

This constant is used to identify a Rotary Encoder Bricklet.

The getIdentity() function and the IPConnection.EnumerateListener listener of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

String BrickletRotaryEncoder.DEVICE_DISPLAY_NAME¶

This constant represents the human readable name of a Rotary Encoder Bricklet.