MATLAB/Octave - Distance IR Bricklet¶

Simple (MATLAB)¶

Download (matlab_example_simple.m)

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

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

    ipcon = IPConnection(); % Create IP connection
    dir = handle(BrickletDistanceIR(UID, ipcon), 'CallbackProperties'); % Create device object

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

    % Get current distance
    distance = dir.getDistance();
    fprintf('Distance: %g cm\n', distance/10.0);

    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.BrickletDistanceIR;

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

    ipcon = IPConnection(); % Create IP connection
    dir = handle(BrickletDistanceIR(UID, ipcon), 'CallbackProperties'); % Create device object

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

    % Register distance callback to function cb_distance
    set(dir, 'DistanceCallback', @(h, e) cb_distance(e));

    % Set period for distance callback to 0.2s (200ms)
    % Note: The distance callback is only called every 0.2 seconds
    %       if the distance has changed since the last call!
    dir.setDistanceCallbackPeriod(200);

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

% Callback function for distance callback
function cb_distance(e)
    fprintf('Distance: %g cm\n', e.distance/10.0);
end

Threshold (MATLAB)¶

Download (matlab_example_threshold.m)

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

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

    ipcon = IPConnection(); % Create IP connection
    dir = handle(BrickletDistanceIR(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)
    dir.setDebouncePeriod(10000);

    % Register distance reached callback to function cb_distance_reached
    set(dir, 'DistanceReachedCallback', @(h, e) cb_distance_reached(e));

    % Configure threshold for distance "smaller than 30 cm"
    dir.setDistanceCallbackThreshold('<', 30*10, 0);

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

% Callback function for distance reached callback
function cb_distance_reached(e)
    fprintf('Distance: %g cm\n', e.distance/10.0);
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 Distance IR Bricklet

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

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

    % Get current distance
    distance = dir.getDistance();
    fprintf("Distance: %g cm\n", distance/10.0);

    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 Distance IR Bricklet

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

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

    % Register distance callback to function cb_distance
    dir.addDistanceCallback(@cb_distance);

    % Set period for distance callback to 0.2s (200ms)
    % Note: The distance callback is only called every 0.2 seconds
    %       if the distance has changed since the last call!
    dir.setDistanceCallbackPeriod(200);

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

% Callback function for distance callback
function cb_distance(e)
    fprintf("Distance: %g cm\n", e.distance/10.0);
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 Distance IR Bricklet

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

    % Register distance reached callback to function cb_distance_reached
    dir.addDistanceReachedCallback(@cb_distance_reached);

    % Configure threshold for distance "smaller than 30 cm"
    dir.setDistanceCallbackThreshold("<", 30*10, 0);

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

% Callback function for distance reached callback
function cb_distance_reached(e)
    fprintf("Distance: %g cm\n", e.distance/10.0);
end

Basic Functions¶

class BrickletDistanceIR(String uid, IPConnection ipcon)¶

Parameters:	uid – Type: String ipcon – Type: IPConnection
Returns:	distanceIR – Type: BrickletDistanceIR

Creates an object with the unique device ID uid.

In MATLAB:

import com.tinkerforge.BrickletDistanceIR;

distanceIR = BrickletDistanceIR('YOUR_DEVICE_UID', ipcon);

In Octave:

distanceIR = java_new("com.tinkerforge.BrickletDistanceIR", "YOUR_DEVICE_UID", ipcon);

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

int BrickletDistanceIR.getDistance()¶

Returns:	distance – Type: int, Unit: 1 mm, Range: [0 to 216 - 1]

Returns the distance measured by the sensor. Possible distance ranges are 40 to 300, 100 to 800 and 200 to 1500, depending on the selected IR sensor.

If you want to get the distance periodically, it is recommended to use the DistanceCallback callback and set the period with setDistanceCallbackPeriod().

Advanced Functions¶

int BrickletDistanceIR.getAnalogValue()¶

Returns:	value – Type: int, Range: [0 to 212 - 1]

Returns the value as read by a 12-bit analog-to-digital converter.

Note

The value returned by getDistance() is averaged over several samples to yield less noise, while getAnalogValue() gives back raw unfiltered analog values. The only reason to use getAnalogValue() is, if you need the full resolution of the analog-to-digital converter.

If you want the analog value periodically, it is recommended to use the AnalogValueCallback callback and set the period with setAnalogValueCallbackPeriod().

void BrickletDistanceIR.setSamplingPoint(short position, int distance)¶

Parameters:	position – Type: short, Range: [0 to 127] distance – Type: int, Unit: 1/10 mm, Range: [0 to 216 - 1]

Sets a sampling point value to a specific position of the lookup table. The lookup table comprises 128 equidistant analog values with corresponding distances.

If you measure a distance of 50cm at the analog value 2048, you should call this function with (64, 5000). The utilized analog-to-digital converter has a resolution of 12 bit. With 128 sampling points on the whole range, this means that every sampling point has a size of 32 analog values. Thus the analog value 2048 has the corresponding sampling point 64 = 2048/32.

Sampling points are saved on the EEPROM of the Distance IR Bricklet and loaded again on startup.

Note

An easy way to calibrate the sampling points of the Distance IR Bricklet is implemented in the Brick Viewer. If you want to calibrate your Bricklet it is highly recommended to use this implementation.

int BrickletDistanceIR.getSamplingPoint(short position)¶

Parameters:	position – Type: short, Range: [0 to 127]
Returns:	distance – Type: int, Unit: 1/10 mm, Range: [0 to 216 - 1]

Returns the distance to a sampling point position as set by setSamplingPoint().

BrickletDistanceIR.Identity BrickletDistanceIR.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 BrickletDistanceIR.setDistanceCallbackPeriod(long period)¶

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

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

The DistanceCallback callback is only triggered if the distance has changed since the last triggering.

long BrickletDistanceIR.getDistanceCallbackPeriod()¶

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

Returns the period as set by setDistanceCallbackPeriod().

void BrickletDistanceIR.setAnalogValueCallbackPeriod(long period)¶

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

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

The AnalogValueCallback callback is only triggered if the analog value has changed since the last triggering.

long BrickletDistanceIR.getAnalogValueCallbackPeriod()¶

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

Returns the period as set by setAnalogValueCallbackPeriod().

void BrickletDistanceIR.setDistanceCallbackThreshold(char option, int min, int max)¶

Parameters:	option – Type: char, Range: See constants, Default: 'x' min – Type: int, Unit: 1 mm, Range: [0 to 216 - 1], Default: 0 max – Type: int, Unit: 1 mm, Range: [0 to 216 - 1], Default: 0

Sets the thresholds for the DistanceReachedCallback callback.

The following options are possible:

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

The following constants are available for this function:

For option:

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

BrickletDistanceIR.DistanceCallbackThreshold BrickletDistanceIR.getDistanceCallbackThreshold()¶

Return Object:	option – Type: char, Range: See constants, Default: 'x' min – Type: int, Unit: 1 mm, Range: [0 to 216 - 1], Default: 0 max – Type: int, Unit: 1 mm, Range: [0 to 216 - 1], Default: 0

Returns the threshold as set by setDistanceCallbackThreshold().

The following constants are available for this function:

For option:

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

void BrickletDistanceIR.setAnalogValueCallbackThreshold(char option, int min, int max)¶

Parameters:	option – Type: char, Range: See constants, Default: 'x' min – Type: int, Range: [0 to 216 - 1], Default: 0 max – Type: int, Range: [0 to 216 - 1], Default: 0

Sets the thresholds for the AnalogValueReachedCallback callback.

The following options are possible:

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

The following constants are available for this function:

For option:

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

BrickletDistanceIR.AnalogValueCallbackThreshold BrickletDistanceIR.getAnalogValueCallbackThreshold()¶

Return Object:	option – Type: char, Range: See constants, Default: 'x' min – Type: int, Range: [0 to 216 - 1], Default: 0 max – Type: int, Range: [0 to 216 - 1], Default: 0

Returns the threshold as set by setAnalogValueCallbackThreshold().

The following constants are available for this function:

For option:

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

void BrickletDistanceIR.setDebouncePeriod(long debounce)¶

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

Sets the period with which the threshold callbacks

• DistanceReachedCallback,
• AnalogValueReachedCallback

are triggered, if the thresholds

• setDistanceCallbackThreshold(),
• setAnalogValueCallbackThreshold()

keep being reached.

long BrickletDistanceIR.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 BrickletDistanceIR.DistanceCallback¶

Event Object:	distance – Type: int, Unit: 1 mm, Range: [0 to 216 - 1]

This callback is triggered periodically with the period that is set by setDistanceCallbackPeriod(). The parameter is the distance of the sensor.

The DistanceCallback callback is only triggered if the distance 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 addDistanceCallback() function. An added callback function can be removed with the removeDistanceCallback() function.

callback BrickletDistanceIR.AnalogValueCallback¶

Event Object:	value – Type: int, Range: [0 to 212 - 1]

This callback is triggered periodically with the period that is set by setAnalogValueCallbackPeriod(). The parameter is the analog value of the sensor.

The AnalogValueCallback callback is only triggered if the analog value 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 addAnalogValueCallback() function. An added callback function can be removed with the removeAnalogValueCallback() function.

callback BrickletDistanceIR.DistanceReachedCallback¶

Event Object:	distance – Type: int, Unit: 1 mm, Range: [0 to 216 - 1]

This callback is triggered when the threshold as set by setDistanceCallbackThreshold() is reached. The parameter is the distance of the sensor.

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 addDistanceReachedCallback() function. An added callback function can be removed with the removeDistanceReachedCallback() function.

callback BrickletDistanceIR.AnalogValueReachedCallback¶

Event Object:	value – Type: int, Range: [0 to 212 - 1]

This callback is triggered when the threshold as set by setAnalogValueCallbackThreshold() is reached. The parameter is the analog value of the sensor.

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 addAnalogValueReachedCallback() function. An added callback function can be removed with the removeAnalogValueReachedCallback() 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[] BrickletDistanceIR.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 BrickletDistanceIR.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:

• BrickletDistanceIR.FUNCTION_SET_SAMPLING_POINT = 3
• BrickletDistanceIR.FUNCTION_SET_DISTANCE_CALLBACK_PERIOD = 5
• BrickletDistanceIR.FUNCTION_SET_ANALOG_VALUE_CALLBACK_PERIOD = 7
• BrickletDistanceIR.FUNCTION_SET_DISTANCE_CALLBACK_THRESHOLD = 9
• BrickletDistanceIR.FUNCTION_SET_ANALOG_VALUE_CALLBACK_THRESHOLD = 11
• BrickletDistanceIR.FUNCTION_SET_DEBOUNCE_PERIOD = 13

void BrickletDistanceIR.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:

• BrickletDistanceIR.FUNCTION_SET_SAMPLING_POINT = 3
• BrickletDistanceIR.FUNCTION_SET_DISTANCE_CALLBACK_PERIOD = 5
• BrickletDistanceIR.FUNCTION_SET_ANALOG_VALUE_CALLBACK_PERIOD = 7
• BrickletDistanceIR.FUNCTION_SET_DISTANCE_CALLBACK_THRESHOLD = 9
• BrickletDistanceIR.FUNCTION_SET_ANALOG_VALUE_CALLBACK_THRESHOLD = 11
• BrickletDistanceIR.FUNCTION_SET_DEBOUNCE_PERIOD = 13

void BrickletDistanceIR.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 BrickletDistanceIR.DEVICE_IDENTIFIER¶

This constant is used to identify a Distance IR 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 BrickletDistanceIR.DEVICE_DISPLAY_NAME¶

This constant represents the human readable name of a Distance IR Bricklet.