Java - Voltage/Current Bricklet

This is the description of the Java API bindings for the Voltage/Current Bricklet. General information and technical specifications for the Voltage/Current Bricklet are summarized in its hardware description.

An installation guide for the Java API bindings is part of their general description.

Examples

The example code below is Public Domain (CC0 1.0).

Simple

Download (ExampleSimple.java)

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import com.tinkerforge.BrickletVoltageCurrent;
import com.tinkerforge.IPConnection;

public class ExampleSimple {
    private static final String HOST = "localhost";
    private static final int PORT = 4223;
    private static final String UID = "ABC"; // Change to your UID
    
    // Note: To make the example code cleaner we do not handle exceptions. Exceptions you
    //       might normally want to catch are described in the commnents below
    public static void main(String args[]) throws Exception {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickletVoltageCurrent vc = new BrickletVoltageCurrent(UID, ipcon); // Create device object

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

        // Get current current and voltage (unit is mA and mV)
        int current = vc.getCurrent(); // Can throw com.tinkerforge.TimeoutException
        int voltage = vc.getVoltage(); // Can throw com.tinkerforge.TimeoutException

        System.out.println("Current: " + current/1000.0 + " A");
        System.out.println("Voltgae: " + voltage/1000.0 + " V");

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

Callback

Download (ExampleCallback.java)

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import com.tinkerforge.BrickletVoltageCurrent;
import com.tinkerforge.IPConnection;

public class ExampleCallback {
    private static final String HOST = "localhost";
    private static final int PORT = 4223;
    private static final String UID = "ABC"; // Change to your UID
    
    // Note: To make the example code cleaner we do not handle exceptions. Exceptions you
    //       might normally want to catch are described in the commnents below
    public static void main(String args[]) throws Exception {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickletVoltageCurrent vc = new BrickletVoltageCurrent(UID, ipcon); // Create device object

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


        // Set Period for current callback to 1s (1000ms)
        // Note: The current callback is only called every second if the 
        //       current has changed since the last call!
        vc.setCurrentCallbackPeriod(1000);

        // Add and implement current listener (called if current changes)
        vc.addCurrentListener(new BrickletVoltageCurrent.CurrentListener() {
            public void current(int current) {
                System.out.println("Current: " + current/1000.0 + " A");
            }
        });

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

Threshold

Download (ExampleThreshold.java)

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import com.tinkerforge.BrickletVoltageCurrent;
import com.tinkerforge.IPConnection;

public class ExampleThreshold {
    private static final String HOST = "localhost";
    private static final int PORT = 4223;
    private static final String UID = "ABC"; // Change to your UID
    
    // Note: To make the example code cleaner we do not handle exceptions. Exceptions you
    //       might normally want to catch are described in the commnents below
    public static void main(String args[]) throws Exception {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickletVoltageCurrent vc = new BrickletVoltageCurrent(UID, ipcon); // Create device object

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


        // Get threshold callbacks with a debounce time of 10 seconds (10000ms)
        vc.setDebouncePeriod(10000);

        // Configure threshold for "greater than 1A" (unit is mA)
        vc.setCurrentCallbackThreshold('>', 1*1000, 0);

        // Add and implement current reached listener (called if current is greater than 1A)
        vc.addCurrentReachedListener(new BrickletVoltageCurrent.CurrentReachedListener() {
            public void currentReached(int current) {
                System.out.println("Current is greater than 1A: " + current/1000.0);
            }
        });

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

API

Generally, every method of the Java bindings that returns a value can throw a TimeoutException. This exception gets thrown if the device did not respond. If a cable based connection is used, it is unlikely that this exception gets thrown (assuming nobody unplugs the device). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.

Beside the TimeoutException there is also a NotConnectedException that is thrown if a method needs to communicate with the device while the IP Connection is not connected.

Since Java does not support multiple return values and return by reference is not possible for primitive types, we use small classes that only consist of member variables. The member variables of the returned objects are described in the corresponding method descriptions.

The package for all Brick/Bricklet bindings and the IP Connection is com.tinkerforge.*

All methods listed below are thread-safe.

Basic Functions

public class BrickletVoltageCurrent(String uid, IPConnection ipcon)

Creates an object with the unique device ID uid:

BrickletVoltageCurrent voltageCurrent = new BrickletVoltageCurrent("YOUR_DEVICE_UID", ipcon);

This object can then be used after the IP Connection is connected (see examples above).

public int getCurrent()

Returns the current. The value is in mA and between -20000mA and 20000mA.

If you want to get the current periodically, it is recommended to use the listener CurrentListener and set the period with setCurrentCallbackPeriod().

public int getVoltage()

Returns the voltage. The value is in mV and between 0mV and 36000mV.

If you want to get the voltage periodically, it is recommended to use the listener VoltageListener and set the period with setVoltageCallbackPeriod().

public int getPower()

Returns the power. The value is in mW and between 0mV and 720000mW.

If you want to get the power periodically, it is recommended to use the listener PowerListener and set the period with setPowerCallbackPeriod().

public void setConfiguration(short averaging, short voltageConversionTime, short currentConversionTime)

Sets the configuration of the Voltage/Current Bricklet. It is possible to configure number of averages as well as voltage and current conversion time.

Averaging:

Value Number of Averages
0 1
1 4
2 16
3 64
4 128
5 256
6 512
>=7 1024

Voltage/Current conversion:

Value Conversion time
0 140µs
1 204µs
2 332µs
3 588µs
4 1.1ms
5 2.116ms
6 4.156ms
>=7 8.244ms

The default values are 3, 4 and 4 (64, 1.1ms, 1.1ms) for averaging, voltage conversion and current conversion.

The following constants are available for this function:

  • BrickletVoltageCurrent.AVERAGING_1 = 0
  • BrickletVoltageCurrent.AVERAGING_4 = 1
  • BrickletVoltageCurrent.AVERAGING_16 = 2
  • BrickletVoltageCurrent.AVERAGING_64 = 3
  • BrickletVoltageCurrent.AVERAGING_128 = 4
  • BrickletVoltageCurrent.AVERAGING_256 = 5
  • BrickletVoltageCurrent.AVERAGING_512 = 6
  • BrickletVoltageCurrent.AVERAGING_1024 = 7
public BrickletVoltageCurrent.Configuration getConfiguration()

Returns the configuration as set by setConfiguration().

The following constants are available for this function:

  • BrickletVoltageCurrent.AVERAGING_1 = 0
  • BrickletVoltageCurrent.AVERAGING_4 = 1
  • BrickletVoltageCurrent.AVERAGING_16 = 2
  • BrickletVoltageCurrent.AVERAGING_64 = 3
  • BrickletVoltageCurrent.AVERAGING_128 = 4
  • BrickletVoltageCurrent.AVERAGING_256 = 5
  • BrickletVoltageCurrent.AVERAGING_512 = 6
  • BrickletVoltageCurrent.AVERAGING_1024 = 7

The returned object has the public member variables short averaging, short voltageConversionTime and short currentConversionTime.

Advanced Functions

public void setCalibration(int gainMultiplier, int gainDivisor)

Since the shunt resistor that is used to measure the current is not perfectly precise, it needs to be calibrated by a multiplier and divisor if a very precise reading is needed.

For example, if you are expecting a measurement of 1000mA and you are measuring 1023mA, you can calibrate the Voltage/Current Bricklet by setting the multiplier to 1000 and the divisor to 1023.

public BrickletVoltageCurrent.Calibration getCalibration()

Returns the calibration as set by setCalibration().

The returned object has the public member variables int gainMultiplier and int gainDivisor.

public short[] getAPIVersion()

Returns the version of the API definition (major, minor, revision) 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.

public boolean getResponseExpected(short functionId)

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 send and errors are silently ignored, because they cannot be detected.

See setResponseExpected() for the list of function ID constants available for this function.

public void setResponseExpected(short functionId, boolean responseExpected)

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 and listeners it is always disabled.

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 send and errors are silently ignored, because they cannot be detected.

The following function ID constants are available for this function:

  • BrickletVoltageCurrent.FUNCTION_SET_CONFIGURATION = 4
  • BrickletVoltageCurrent.FUNCTION_SET_CALIBRATION = 6
  • BrickletVoltageCurrent.FUNCTION_SET_CURRENT_CALLBACK_PERIOD = 8
  • BrickletVoltageCurrent.FUNCTION_SET_VOLTAGE_CALLBACK_PERIOD = 10
  • BrickletVoltageCurrent.FUNCTION_SET_POWER_CALLBACK_PERIOD = 12
  • BrickletVoltageCurrent.FUNCTION_SET_CURRENT_CALLBACK_THRESHOLD = 14
  • BrickletVoltageCurrent.FUNCTION_SET_VOLTAGE_CALLBACK_THRESHOLD = 16
  • BrickletVoltageCurrent.FUNCTION_SET_POWER_CALLBACK_THRESHOLD = 18
  • BrickletVoltageCurrent.FUNCTION_SET_DEBOUNCE_PERIOD = 20
public void setResponseExpectedAll(boolean responseExpected)

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

public BrickletVoltageCurrent.Identity getIdentity()

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' or 'd'.

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

The returned object has the public member variables String uid, String connectedUid, char position, short[] hardwareVersion, short[] firmwareVersion and int deviceIdentifier.

Listener Configuration Functions

public void setCurrentCallbackPeriod(long period)

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

CurrentListener is only triggered if the current has changed since the last triggering.

The default value is 0.

public long getCurrentCallbackPeriod()

Returns the period as set by setCurrentCallbackPeriod().

public void setVoltageCallbackPeriod(long period)

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

VoltageListener is only triggered if the voltage has changed since the last triggering.

The default value is 0.

public long getVoltageCallbackPeriod()

Returns the period as set by setVoltageCallbackPeriod().

public void setPowerCallbackPeriod(long period)

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

PowerListener is only triggered if the power has changed since the last triggering.

The default value is 0.

public long getPowerCallbackPeriod()

Returns the period as set by getPowerCallbackPeriod().

public void setCurrentCallbackThreshold(char option, int min, int max)

Sets the thresholds for the CurrentReachedListener listener.

The following options are possible:

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

The default value is ('x', 0, 0).

The following constants are available for this function:

  • BrickletVoltageCurrent.THRESHOLD_OPTION_OFF = 'x'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_SMALLER = '<'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_GREATER = '>'
public BrickletVoltageCurrent.CurrentCallbackThreshold getCurrentCallbackThreshold()

Returns the threshold as set by setCurrentCallbackThreshold().

The following constants are available for this function:

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

The returned object has the public member variables char option, int min and int max.

public void setVoltageCallbackThreshold(char option, int min, int max)

Sets the thresholds for the VoltageReachedListener listener.

The following options are possible:

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

The default value is ('x', 0, 0).

The following constants are available for this function:

  • BrickletVoltageCurrent.THRESHOLD_OPTION_OFF = 'x'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_SMALLER = '<'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_GREATER = '>'
public BrickletVoltageCurrent.VoltageCallbackThreshold getVoltageCallbackThreshold()

Returns the threshold as set by setVoltageCallbackThreshold().

The following constants are available for this function:

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

The returned object has the public member variables char option, int min and int max.

public void setPowerCallbackThreshold(char option, int min, int max)

Sets the thresholds for the PowerReachedListener listener.

The following options are possible:

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

The default value is ('x', 0, 0).

The following constants are available for this function:

  • BrickletVoltageCurrent.THRESHOLD_OPTION_OFF = 'x'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_SMALLER = '<'
  • BrickletVoltageCurrent.THRESHOLD_OPTION_GREATER = '>'
public BrickletVoltageCurrent.PowerCallbackThreshold getPowerCallbackThreshold()

Returns the threshold as set by setPowerCallbackThreshold().

The following constants are available for this function:

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

The returned object has the public member variables char option, int min and int max.

public void setDebouncePeriod(long debounce)

Sets the period in ms with which the threshold listeners

are triggered, if the thresholds

keep being reached.

The default value is 100.

public long getDebouncePeriod()

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 BrickletVoltageCurrent.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.

Note

Using listeners for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.

public class BrickletVoltageCurrent.CurrentListener()

This listener can be added with the addCurrentListener() function. An added listener can be removed with the removeCurrentListener() function.

public void current(int current)

This listener is triggered periodically with the period that is set by setCurrentCallbackPeriod(). The parameter is the current of the sensor.

CurrentListener is only triggered if the current has changed since the last triggering.

public class BrickletVoltageCurrent.VoltageListener()

This listener can be added with the addVoltageListener() function. An added listener can be removed with the removeVoltageListener() function.

public void voltage(int voltage)

This listener is triggered periodically with the period that is set by setVoltageCallbackPeriod(). The parameter is the voltage of the sensor.

VoltageListener is only triggered if the voltage has changed since the last triggering.

public class BrickletVoltageCurrent.PowerListener()

This listener can be added with the addPowerListener() function. An added listener can be removed with the removePowerListener() function.

public void power(int power)

This listener is triggered periodically with the period that is set by setPowerCallbackPeriod(). The parameter is the power of the sensor.

PowerListener is only triggered if the power has changed since the last triggering.

public class BrickletVoltageCurrent.CurrentReachedListener()

This listener can be added with the addCurrentReachedListener() function. An added listener can be removed with the removeCurrentReachedListener() function.

public void currentReached(int current)

This listener is triggered when the threshold as set by setCurrentCallbackThreshold() is reached. The parameter is the current of the sensor.

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

public class BrickletVoltageCurrent.VoltageReachedListener()

This listener can be added with the addVoltageReachedListener() function. An added listener can be removed with the removeVoltageReachedListener() function.

public void voltageReached(int voltage)

This listener is triggered when the threshold as set by setVoltageCallbackThreshold() is reached. The parameter is the voltage of the sensor.

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

public class BrickletVoltageCurrent.PowerReachedListener()

This listener can be added with the addPowerReachedListener() function. An added listener can be removed with the removePowerReachedListener() function.

public void powerReached(int power)

This listener is triggered when the threshold as set by setPowerCallbackThreshold() is reached. The parameter is the power of the sensor.

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

Constants

public static final int BrickletVoltageCurrent.DEVICE_IDENTIFIER

This constant is used to identify a Voltage/Current Bricklet.

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

Creative Commons Licence The content of this page is licensed under Creative Commons Attribution 3.0 Unported License.