MATLAB/Octave - Thermocouple Bricklet¶

Simple (MATLAB)¶

Download (matlab_example_simple.m)

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function matlab_example_simple()
    import com.tinkerforge.IPConnection;
    import com.tinkerforge.BrickletThermocouple;

    HOST = 'localhost';
    PORT = 4223;
    UID = 'XYZ'; % Change XYZ to the UID of your Thermocouple Bricklet

    ipcon = IPConnection(); % Create IP connection
    t = handle(BrickletThermocouple(UID, ipcon), 'CallbackProperties'); % Create device object

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

    % Get current temperature
    temperature = t.getTemperature();
    fprintf('Temperature: %g °C\n', temperature/100.0);

    input('Press key to exit\n', 's');
    ipcon.disconnect();
end

Callback (MATLAB)¶

Download (matlab_example_callback.m)

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function matlab_example_callback()
    import com.tinkerforge.IPConnection;
    import com.tinkerforge.BrickletThermocouple;

    HOST = 'localhost';
    PORT = 4223;
    UID = 'XYZ'; % Change XYZ to the UID of your Thermocouple Bricklet

    ipcon = IPConnection(); % Create IP connection
    t = handle(BrickletThermocouple(UID, ipcon), 'CallbackProperties'); % Create device object

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

    % Register temperature callback to function cb_temperature
    set(t, 'TemperatureCallback', @(h, e) cb_temperature(e));

    % 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!
    t.setTemperatureCallbackPeriod(1000);

    input('Press key to exit\n', 's');
    ipcon.disconnect();
end

% Callback function for temperature callback
function cb_temperature(e)
    fprintf('Temperature: %g °C\n', e.temperature/100.0);
end

Threshold (MATLAB)¶

Download (matlab_example_threshold.m)

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function matlab_example_threshold()
    import com.tinkerforge.IPConnection;
    import com.tinkerforge.BrickletThermocouple;

    HOST = 'localhost';
    PORT = 4223;
    UID = 'XYZ'; % Change XYZ to the UID of your Thermocouple Bricklet

    ipcon = IPConnection(); % Create IP connection
    t = handle(BrickletThermocouple(UID, ipcon), 'CallbackProperties'); % 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)
    t.setDebouncePeriod(10000);

    % Register temperature reached callback to function cb_temperature_reached
    set(t, 'TemperatureReachedCallback', @(h, e) cb_temperature_reached(e));

    % Configure threshold for temperature "greater than 30 °C"
    t.setTemperatureCallbackThreshold('>', 30*100, 0);

    input('Press key to exit\n', 's');
    ipcon.disconnect();
end

% Callback function for temperature reached callback
function cb_temperature_reached(e)
    fprintf('Temperature: %g °C\n', e.temperature/100.0);
end

Simple (Octave)¶

Download (octave_example_simple.m)

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function octave_example_simple()
    more off;

    HOST = "localhost";
    PORT = 4223;
    UID = "XYZ"; % Change XYZ to the UID of your Thermocouple Bricklet

    ipcon = javaObject("com.tinkerforge.IPConnection"); % Create IP connection
    t = javaObject("com.tinkerforge.BrickletThermocouple", UID, ipcon); % Create device object

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

    % Get current temperature
    temperature = t.getTemperature();
    fprintf("Temperature: %g °C\n", temperature/100.0);

    input("Press key to exit\n", "s");
    ipcon.disconnect();
end

Callback (Octave)¶

Download (octave_example_callback.m)

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function octave_example_callback()
    more off;

    HOST = "localhost";
    PORT = 4223;
    UID = "XYZ"; % Change XYZ to the UID of your Thermocouple Bricklet

    ipcon = javaObject("com.tinkerforge.IPConnection"); % Create IP connection
    t = javaObject("com.tinkerforge.BrickletThermocouple", UID, ipcon); % Create device object

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

    % Register temperature callback to function cb_temperature
    t.addTemperatureCallback(@cb_temperature);

    % 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!
    t.setTemperatureCallbackPeriod(1000);

    input("Press key to exit\n", "s");
    ipcon.disconnect();
end

% Callback function for temperature callback
function cb_temperature(e)
    fprintf("Temperature: %g °C\n", e.temperature/100.0);
end

Threshold (Octave)¶

Download (octave_example_threshold.m)

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function octave_example_threshold()
    more off;

    HOST = "localhost";
    PORT = 4223;
    UID = "XYZ"; % Change XYZ to the UID of your Thermocouple Bricklet

    ipcon = javaObject("com.tinkerforge.IPConnection"); % Create IP connection
    t = javaObject("com.tinkerforge.BrickletThermocouple", 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)
    t.setDebouncePeriod(10000);

    % Register temperature reached callback to function cb_temperature_reached
    t.addTemperatureReachedCallback(@cb_temperature_reached);

    % Configure threshold for temperature "greater than 30 °C"
    t.setTemperatureCallbackThreshold(">", 30*100, 0);

    input("Press key to exit\n", "s");
    ipcon.disconnect();
end

% Callback function for temperature reached callback
function cb_temperature_reached(e)
    fprintf("Temperature: %g °C\n", e.temperature/100.0);
end

Basic Functions¶

class BrickletThermocouple(String uid, IPConnection ipcon)¶

Parameters:	uid – Type: String ipcon – Type: IPConnection
Returns:	thermocouple – Type: BrickletThermocouple

Creates an object with the unique device ID uid.

In MATLAB:

import com.tinkerforge.BrickletThermocouple;

thermocouple = BrickletThermocouple('YOUR_DEVICE_UID', ipcon);

In Octave:

thermocouple = java_new("com.tinkerforge.BrickletThermocouple", "YOUR_DEVICE_UID", ipcon);

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

int BrickletThermocouple.getTemperature()¶

Returns:	temperature – Type: int, Unit: 1/100 °C, Range: [-21000 to 180000]

Returns the temperature of the thermocouple.

If you want to get the temperature periodically, it is recommended to use the TemperatureCallback callback and set the period with setTemperatureCallbackPeriod().

Advanced Functions¶

void BrickletThermocouple.setConfiguration(short averaging, short thermocoupleType, short filter)¶

Parameters:	averaging – Type: short, Range: See constants, Default: 16 thermocoupleType – Type: short, Range: See constants, Default: 3 filter – Type: short, Range: See constants, Default: 0

You can configure averaging size, thermocouple type and frequency filtering.

Available averaging sizes are 1, 2, 4, 8 and 16 samples.

As thermocouple type you can use B, E, J, K, N, R, S and T. If you have a different thermocouple or a custom thermocouple you can also use G8 and G32. With these types the returned value will not be in °C/100, it will be calculated by the following formulas:

• G8: value = 8 * 1.6 * 2^17 * Vin
• G32: value = 32 * 1.6 * 2^17 * Vin

where Vin is the thermocouple input voltage.

The frequency filter can be either configured to 50Hz or to 60Hz. You should configure it according to your utility frequency.

The conversion time depends on the averaging and filter configuration, it can be calculated as follows:

• 60Hz: time = 82 + (samples - 1) * 16.67
• 50Hz: time = 98 + (samples - 1) * 20

The following constants are available for this function:

For averaging:

• BrickletThermocouple.AVERAGING_1 = 1
• BrickletThermocouple.AVERAGING_2 = 2
• BrickletThermocouple.AVERAGING_4 = 4
• BrickletThermocouple.AVERAGING_8 = 8
• BrickletThermocouple.AVERAGING_16 = 16

For thermocoupleType:

• BrickletThermocouple.TYPE_B = 0
• BrickletThermocouple.TYPE_E = 1
• BrickletThermocouple.TYPE_J = 2
• BrickletThermocouple.TYPE_K = 3
• BrickletThermocouple.TYPE_N = 4
• BrickletThermocouple.TYPE_R = 5
• BrickletThermocouple.TYPE_S = 6
• BrickletThermocouple.TYPE_T = 7
• BrickletThermocouple.TYPE_G8 = 8
• BrickletThermocouple.TYPE_G32 = 9

For filter:

• BrickletThermocouple.FILTER_OPTION_50HZ = 0
• BrickletThermocouple.FILTER_OPTION_60HZ = 1

BrickletThermocouple.Configuration BrickletThermocouple.getConfiguration()¶

Return Object:	averaging – Type: short, Range: See constants, Default: 16 thermocoupleType – Type: short, Range: See constants, Default: 3 filter – Type: short, Range: See constants, Default: 0

Returns the configuration as set by setConfiguration().

The following constants are available for this function:

For averaging:

• BrickletThermocouple.AVERAGING_1 = 1
• BrickletThermocouple.AVERAGING_2 = 2
• BrickletThermocouple.AVERAGING_4 = 4
• BrickletThermocouple.AVERAGING_8 = 8
• BrickletThermocouple.AVERAGING_16 = 16

For thermocoupleType:

• BrickletThermocouple.TYPE_B = 0
• BrickletThermocouple.TYPE_E = 1
• BrickletThermocouple.TYPE_J = 2
• BrickletThermocouple.TYPE_K = 3
• BrickletThermocouple.TYPE_N = 4
• BrickletThermocouple.TYPE_R = 5
• BrickletThermocouple.TYPE_S = 6
• BrickletThermocouple.TYPE_T = 7
• BrickletThermocouple.TYPE_G8 = 8
• BrickletThermocouple.TYPE_G32 = 9

For filter:

• BrickletThermocouple.FILTER_OPTION_50HZ = 0
• BrickletThermocouple.FILTER_OPTION_60HZ = 1

BrickletThermocouple.ErrorState BrickletThermocouple.getErrorState()¶

Return Object:	overUnder – Type: boolean openCircuit – Type: boolean

Returns the current error state. There are two possible errors:

• Over/Under Voltage and
• Open Circuit.

Over/Under Voltage happens for voltages below 0V or above 3.3V. In this case it is very likely that your thermocouple is defective. An Open Circuit error indicates that there is no thermocouple connected.

You can use the ErrorStateCallback callback to automatically get triggered when the error state changes.

BrickletThermocouple.Identity BrickletThermocouple.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 1: major – Type: short, Range: [0 to 255] 2: minor – Type: short, Range: [0 to 255] 3: revision – Type: short, Range: [0 to 255] firmwareVersion – Type: short[], Length: 3 1: major – Type: short, Range: [0 to 255] 2: minor – Type: short, Range: [0 to 255] 3: 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.

Callback Configuration Functions¶

void BrickletThermocouple.setTemperatureCallbackPeriod(long period)¶

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

Sets the period with which the TemperatureCallback callback is triggered periodically. A value of 0 turns the callback off.

The TemperatureCallback callback is only triggered if the temperature has changed since the last triggering.

long BrickletThermocouple.getTemperatureCallbackPeriod()¶

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

Returns the period as set by setTemperatureCallbackPeriod().

void BrickletThermocouple.setTemperatureCallbackThreshold(char option, int min, int max)¶

Parameters:	option – Type: char, Range: See constants, Default: 'x' min – Type: int, Unit: 1/100 °C, Range: [-231 to 231 - 1], Default: 0 max – Type: int, Unit: 1/100 °C, Range: [-231 to 231 - 1], Default: 0

Sets the thresholds for the TemperatureReachedCallback callback.

The following options are possible:

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

The following constants are available for this function:

For option:

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

BrickletThermocouple.TemperatureCallbackThreshold BrickletThermocouple.getTemperatureCallbackThreshold()¶

Return Object:	option – Type: char, Range: See constants, Default: 'x' min – Type: int, Unit: 1/100 °C, Range: [-231 to 231 - 1], Default: 0 max – Type: int, Unit: 1/100 °C, Range: [-231 to 231 - 1], Default: 0

Returns the threshold as set by setTemperatureCallbackThreshold().

The following constants are available for this function:

For option:

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

void BrickletThermocouple.setDebouncePeriod(long debounce)¶

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

Sets the period with which the threshold callback

• TemperatureReachedCallback

is triggered, if the threshold

• setTemperatureCallbackThreshold()

keeps being reached.

long BrickletThermocouple.getDebouncePeriod()¶

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

Returns the debounce period as set by setDebouncePeriod().

Callbacks¶

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with "set" function of MATLAB. The parameters consist of the IP Connection object, the callback name and the callback function. For example, it looks like this in MATLAB:

function my_callback(e)
    fprintf('Parameter: %s\n', e.param);
end

set(device, 'ExampleCallback', @(h, e) my_callback(e));

Due to a difference in the Octave Java support the "set" function cannot be used in Octave. The registration is done with "add*Callback" functions of the device object. It looks like this in Octave:

function my_callback(e)
    fprintf("Parameter: %s\n", e.param);
end

device.addExampleCallback(@my_callback);

It is possible to add several callbacks and to remove them with the corresponding "remove*Callback" function.

The parameters of the callback are passed to the callback function as fields of the structure e, which is derived from the java.util.EventObject class. The available callback names with corresponding structure fields are described below.

callback BrickletThermocouple.TemperatureCallback¶

Event Object:	temperature – Type: int, Unit: 1/100 °C, Range: [-21000 to 180000]

This callback is triggered periodically with the period that is set by setTemperatureCallbackPeriod(). The parameter is the temperature of the thermocouple.

The TemperatureCallback callback is only triggered if the temperature has changed since the last triggering.

In MATLAB the set() function can be used to register a callback function to this callback.

In Octave a callback function can be added to this callback using the addTemperatureCallback() function. An added callback function can be removed with the removeTemperatureCallback() function.

callback BrickletThermocouple.TemperatureReachedCallback¶

Event Object:	temperature – Type: int, Unit: 1/100 °C, Range: [-21000 to 180000]

This callback is triggered when the threshold as set by setTemperatureCallbackThreshold() is reached. The parameter is the temperature of the thermocouple.

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

In MATLAB the set() function can be used to register a callback function to this callback.

In Octave a callback function can be added to this callback using the addTemperatureReachedCallback() function. An added callback function can be removed with the removeTemperatureReachedCallback() function.

callback BrickletThermocouple.ErrorStateCallback¶

Event Object:	overUnder – Type: boolean openCircuit – Type: boolean

This Callback is triggered every time the error state changes (see getErrorState()).

In MATLAB the set() function can be used to register a callback function to this callback.

In Octave a callback function can be added to this callback using the addErrorStateCallback() function. An added callback function can be removed with the removeErrorStateCallback() function.

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[] BrickletThermocouple.getAPIVersion()¶

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

• BrickletThermocouple.FUNCTION_SET_TEMPERATURE_CALLBACK_PERIOD = 2
• BrickletThermocouple.FUNCTION_SET_TEMPERATURE_CALLBACK_THRESHOLD = 4
• BrickletThermocouple.FUNCTION_SET_DEBOUNCE_PERIOD = 6
• BrickletThermocouple.FUNCTION_SET_CONFIGURATION = 10

void BrickletThermocouple.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 callback 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:

• BrickletThermocouple.FUNCTION_SET_TEMPERATURE_CALLBACK_PERIOD = 2
• BrickletThermocouple.FUNCTION_SET_TEMPERATURE_CALLBACK_THRESHOLD = 4
• BrickletThermocouple.FUNCTION_SET_DEBOUNCE_PERIOD = 6
• BrickletThermocouple.FUNCTION_SET_CONFIGURATION = 10

void BrickletThermocouple.setResponseExpectedAll(boolean responseExpected)¶

Parameters:	responseExpected – Type: boolean

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

Constants¶

int BrickletThermocouple.DEVICE_IDENTIFIER¶

This constant is used to identify a Thermocouple Bricklet.

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

String BrickletThermocouple.DEVICE_DISPLAY_NAME¶

This constant represents the human readable name of a Thermocouple Bricklet.