This is the description of the Java API bindings for the PTC Bricklet. General information and technical specifications for the PTC Bricklet are summarized in its hardware description.
An installation guide for the Java API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 | import com.tinkerforge.BrickletPTC;
import com.tinkerforge.IPConnection;
public class ExampleSimple {
private static final String HOST = "localhost";
private static final int PORT = 4223;
private static final String UID = "XYZ"; // 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 documentation
public static void main(String args[]) throws Exception {
IPConnection ipcon = new IPConnection(); // Create IP connection
BrickletPTC ptc = new BrickletPTC(UID, ipcon); // Create device object
ipcon.connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected
// Get current temperature (unit is °C/100)
int temperature = ptc.getTemperature(); // Can throw com.tinkerforge.TimeoutException
System.out.println("Temperature: " + temperature/100.0 + " °C");
System.out.println("Press key to exit"); System.in.read();
ipcon.disconnect();
}
}
|
Download (ExampleCallback.java)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 | import com.tinkerforge.BrickletPTC;
import com.tinkerforge.IPConnection;
public class ExampleCallback {
private static final String HOST = "localhost";
private static final int PORT = 4223;
private static final String UID = "XYZ"; // 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 documentation
public static void main(String args[]) throws Exception {
IPConnection ipcon = new IPConnection(); // Create IP connection
BrickletPTC ptc = new BrickletPTC(UID, ipcon); // Create device object
ipcon.connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected
// Set Period for temperature callback to 1s (1000ms)
// Note: The temperature callback is only called every second if the
// temperature has changed since the last call!
ptc.setTemperatureCallbackPeriod(1000);
// Add and implement temperature listener (called if temperature changes)
ptc.addTemperatureListener(new BrickletPTC.TemperatureListener() {
public void temperature(int temperature) {
System.out.println("Temperature: " + temperature/100.0 + " °C");
}
});
System.out.println("Press key to exit"); System.in.read();
ipcon.disconnect();
}
}
|
Download (ExampleThreshold.java)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 | import com.tinkerforge.BrickletPTC;
import com.tinkerforge.IPConnection;
public class ExampleThreshold {
private static final String HOST = "localhost";
private static final int PORT = 4223;
private static final String UID = "XYZ"; // 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 documentation
public static void main(String args[]) throws Exception {
IPConnection ipcon = new IPConnection(); // Create IP connection
BrickletPTC ptc = new BrickletPTC(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)
ptc.setDebouncePeriod(10000);
// Configure threshold for "greater than 30 °C" (unit is °C/100)
ptc.setTemperatureCallbackThreshold('>', 30*100, 0);
// Add and implement temperature reached listener
// (called if temperature is greater than 30 °C)
ptc.addTemperatureReachedListener(new BrickletPTC.TemperatureReachedListener() {
public void temperatureReached(int temperature) {
System.out.println("We have " + temperature/100.0 + " °C.");
System.out.println("It is too hot, we need air conditioning!");
}
});
System.out.println("Press key to exit"); System.in.read();
ipcon.disconnect();
}
}
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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.
Creates an object with the unique device ID uid:
BrickletPTC ptc = new BrickletPTC("YOUR_DEVICE_UID", ipcon);
This object can then be used after the IP Connection is connected (see examples above).
Returns the temperature of connected sensor. The value has a range of -246 to 849 °C and is given in °C/100, e.g. a value of 4223 means that a temperature of 42.23 °C is measured.
If you want to get the temperature periodically, it is recommended to use the listener TemperatureListener and set the period with setTemperatureCallbackPeriod().
Returns true if the sensor is connected correctly.
If this function returns false, there is either no Pt100 or Pt1000 sensor connected, the sensor is connected incorrectly or the sensor itself is faulty.
Sets the wire mode of the sensor. Possible values are 2, 3 and 4 which correspond to 2-, 3- and 4-wire sensors. The value has to match the jumper configuration on the Bricklet.
The default value is 2 = 2-wire.
The following constants are available for this function:
Returns the wire mode as set by setWireMode()
The following constants are available for this function:
Returns the value as measured by the MAX31865 precision delta-sigma ADC.
The value can be converted with the following formulas:
If you want to get the resistance periodically, it is recommended to use the listener ResistanceListener and set the period with setResistanceCallbackPeriod().
Sets the noise rejection filter to either 50Hz (0) or 60Hz (1). Noise from 50Hz or 60Hz power sources (including harmonics of the AC power's fundamental frequency) is attenuated by 82dB.
Default value is 0 = 50Hz.
The following constants are available for this function:
Returns the noise rejection filter option as set by setNoiseRejectionFilter()
The following constants are available for this function:
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.
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.
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:
Changes the response expected flag for all setter and listener configuration functions of this device at once.
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.
Sets the period in ms with which the TemperatureListener listener is triggered periodically. A value of 0 turns the listener off.
TemperatureListener is only triggered if the temperature has changed since the last triggering.
The default value is 0.
Returns the period as set by setTemperatureCallbackPeriod().
Sets the period in ms with which the ResistanceListener listener is triggered periodically. A value of 0 turns the listener off.
ResistanceListener is only triggered if the resistance has changed since the last triggering.
The default value is 0.
Returns the period as set by setResistanceCallbackPeriod().
Sets the thresholds for the TemperatureReachedListener listener.
The following options are possible:
Option | Description |
---|---|
'x' | Listener is turned off |
'o' | Listener is triggered when the temperature is outside the min and max values |
'i' | Listener is triggered when the temperature is inside the min and max values |
'<' | Listener is triggered when the temperature is smaller than the min value (max is ignored) |
'>' | Listener is triggered when the temperature is greater than the min value (max is ignored) |
The default value is ('x', 0, 0).
The following constants are available for this function:
Returns the threshold as set by setTemperatureCallbackThreshold().
The following constants are available for this function:
The returned object has the public member variables char option, int min and int max.
Sets the thresholds for the ResistanceReachedListener listener.
The following options are possible:
Option | Description |
---|---|
'x' | Listener is turned off |
'o' | Listener is triggered when the temperature is outside the min and max values |
'i' | Listener is triggered when the temperature is inside the min and max values |
'<' | Listener is triggered when the temperature is smaller than the min value (max is ignored) |
'>' | Listener is triggered when the temperature is greater than the min value (max is ignored) |
The default value is ('x', 0, 0).
The following constants are available for this function:
Returns the threshold as set by setResistanceCallbackThreshold().
The following constants are available for this function:
The returned object has the public member variables char option, int min and int max.
Sets the period in ms with which the threshold listener
is triggered, if the threshold
keeps being reached.
The default value is 100.
Returns the debounce period as set by setDebouncePeriod().
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 BrickletPTC.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.
This listener can be added with the addTemperatureListener() function. An added listener can be removed with the removeTemperatureListener() function.
This listener is triggered periodically with the period that is set by setTemperatureCallbackPeriod(). The parameter is the temperature of the connected sensor.
TemperatureListener is only triggered if the temperature has changed since the last triggering.
This listener can be added with the addTemperatureReachedListener() function. An added listener can be removed with the removeTemperatureReachedListener() function.
This listener is triggered when the threshold as set by setTemperatureCallbackThreshold() is reached. The parameter is the temperature of the connected sensor.
If the threshold keeps being reached, the listener is triggered periodically with the period as set by setDebouncePeriod().
This listener can be added with the addResistanceListener() function. An added listener can be removed with the removeResistanceListener() function.
This listener is triggered periodically with the period that is set by setResistanceCallbackPeriod(). The parameter is the resistance of the connected sensor.
ResistanceListener is only triggered if the resistance has changed since the last triggering.
This listener can be added with the addResistanceReachedListener() function. An added listener can be removed with the removeResistanceReachedListener() function.
This listener is triggered when the threshold as set by setResistanceCallbackThreshold() is reached. The parameter is the resistance of the connected sensor.
If the threshold keeps being reached, the listener is triggered periodically with the period as set by setDebouncePeriod().
This constant is used to identify a PTC 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.