MATLAB/Octave - LED Strip Bricklet¶

This is the description of the MATLAB/Octave API bindings for the LED Strip Bricklet. General information and technical specifications for the LED Strip Bricklet are summarized in its hardware description.

An installation guide for the MATLAB/Octave API bindings is part of their general description.

Examples¶

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

Simple (MATLAB)¶

Download (matlab_example_simple.m)

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

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

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

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

    % Set first 10 LEDs to green
    ls.setRGBValues(0, 10, [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0], ...
                    [255 255 255 255 255 255 255 255 255 255 0 0 0 0 0 0], ...
                    [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]);

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

Callback (MATLAB)¶

Download (matlab_example_callback.m)

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

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

    global NUM_LEDS;
    global r;
    global g;
    global b;
    global r_index;

    NUM_LEDS = 16;
    r = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0];
    g = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0];
    b = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0];
    r_index = 1;

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

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

    % Set frame duration to 50ms (20 frames per second)
    ls.setFrameDuration(50);

    % Register frame rendered callback to function cb_frame_rendered
    set(ls, 'FrameRenderedCallback', @(h, e) cb_frame_rendered(e));

    % Set initial rgb values to get started
    ls.setRGBValues(1, NUM_LEDS, r, g, b);

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

% Use frame rendered callback to move the active LED every frame
function cb_frame_rendered(e)
    global NUM_LEDS;
    global r_index;
    global r;
    global g;
    global b;

    ls = e.getSource();
    b(r_index) = 1;

    if r_index == NUM_LEDS
        r_index = 1;
    else
        r_index = r_index + 1;
    end

    b(r_index) = 255;

    % Set new data for next render cycle
    ls.setRGBValues(1, NUM_LEDS, r, g, b);
end

Simple (Octave)¶

Download (octave_example_simple.m)

function octave_example_simple()
    more off;

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

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

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

    % Set first 10 LEDs to green
    ls.setRGBValues(0, 10, [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0], ...
                    [255 255 255 255 255 255 255 255 255 255 0 0 0 0 0 0], ...
                    [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]);

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

Callback (Octave)¶

Download (octave_example_callback.m)

function octave_example_callback()
    more off;

    HOST = "localhost";
    PORT = 4223;
    UID = "XYZ"; % Change XYZ to the UID of your LED Strip Bricklet
    
    global NUM_LEDS;
    global r;
    global g;
    global b;
    global r_index;

    NUM_LEDS = 16;
    r = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0];
    g = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0];
    b = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0];
    r_index = 1;

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

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

    % Set frame duration to 50ms (20 frames per second)
    ls.setFrameDuration(50);

    % Register frame rendered callback to function cb_frame_rendered
    ls.addFrameRenderedCallback(@cb_frame_rendered);

    % Set initial rgb values to get started
    ls.setRGBValues(1, NUM_LEDS, r, g, b);

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

% Use frame rendered callback to move the active LED every frame
function cb_frame_rendered(e)
    global NUM_LEDS;
    global r_index;
    global r;
    global g;
    global b;

    ls = e.getSource();
    b(r_index) = 1;

    if r_index == NUM_LEDS
        r_index = 1;
    else
        r_index = r_index + 1;
    end

    b(r_index) = 255;

    % Set new data for next render cycle
    ls.setRGBValues(1, NUM_LEDS, r, g, b);
end

API¶

Generally, every method of the MATLAB 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 the MATLAB bindings are based on Java and 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¶

class BrickletLEDStrip(String uid, IPConnection ipcon)¶

Parameters:	uid – Type: String ipcon – Type: IPConnection
Returns:	ledStrip – Type: BrickletLEDStrip

Creates an object with the unique device ID uid.

In MATLAB:

import com.tinkerforge.BrickletLEDStrip;

ledStrip = BrickletLEDStrip('YOUR_DEVICE_UID', ipcon);

In Octave:

ledStrip = java_new("com.tinkerforge.BrickletLEDStrip", "YOUR_DEVICE_UID", ipcon);

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

void BrickletLEDStrip.setRGBValues(int index, short length, short[] r, short[] g, short[] b)¶

Parameters:	index – Type: int, Range: [0 to 319] length – Type: short, Range: [0 to 16] r – Type: short[], Length: 16, Range: [0 to 255] g – Type: short[], Length: 16, Range: [0 to 255] b – Type: short[], Length: 16, Range: [0 to 255]

Sets length RGB values for the LEDs starting from index.

To make the colors show correctly you need to configure the chip type (setChipType()) and a 3-channel channel mapping (setChannelMapping()) according to the connected LEDs.

Example: If you set

index to 5,
length to 3,
r to [255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
g to [0, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0] and
b to [0, 0, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]

the LED with index 5 will be red, 6 will be green and 7 will be blue.

Note

Depending on the LED circuitry colors can be permuted.

The colors will be transfered to actual LEDs when the next frame duration ends, see setFrameDuration().

Generic approach:

Set the frame duration to a value that represents the number of frames per second you want to achieve.
Set all of the LED colors for one frame.
Wait for the FrameRenderedCallback callback.
Set all of the LED colors for next frame.
Wait for the FrameRenderedCallback callback.
and so on.

This approach ensures that you can change the LED colors with a fixed frame rate.

The actual number of controllable LEDs depends on the number of free Bricklet ports. See here for more information. A call of setRGBValues() with index + length above the bounds is ignored completely.

BrickletLEDStrip.RGBValues BrickletLEDStrip.getRGBValues(int index, short length)¶

Parameters:	index – Type: int, Range: [0 to 319] length – Type: short, Range: [0 to 16]
Return Object:	r – Type: short[], Length: 16, Range: [0 to 255] g – Type: short[], Length: 16, Range: [0 to 255] b – Type: short[], Length: 16, Range: [0 to 255]

Returns length R, G and B values starting from the given LED index.

The values are the last values that were set by setRGBValues().

void BrickletLEDStrip.setFrameDuration(int duration)¶

Parameters:	duration – Type: int, Unit: 1 ms, Range: [0 to 2¹⁶ - 1], Default: 100

Sets the frame duration.

Example: If you want to achieve 20 frames per second, you should set the frame duration to 50ms (50ms * 20 = 1 second).

For an explanation of the general approach see setRGBValues().

int BrickletLEDStrip.getFrameDuration()¶

Returns:	duration – Type: int, Unit: 1 ms, Range: [0 to 2¹⁶ - 1], Default: 100

Returns the frame duration as set by setFrameDuration().

int BrickletLEDStrip.getSupplyVoltage()¶

Returns:	voltage – Type: int, Unit: 1 mV, Range: [0 to 2¹⁶ - 1]

Returns the current supply voltage of the LEDs.

void BrickletLEDStrip.setClockFrequency(long frequency)¶

Parameters:	frequency – Type: long, Unit: 1 Hz, Range: [10000 to 2000000], Default: 1666666

Sets the frequency of the clock.

The Bricklet will choose the nearest achievable frequency, which may be off by a few Hz. You can get the exact frequency that is used by calling getClockFrequency().

If you have problems with flickering LEDs, they may be bits flipping. You can fix this by either making the connection between the LEDs and the Bricklet shorter or by reducing the frequency.

With a decreasing frequency your maximum frames per second will decrease too.

Note

The frequency in firmware version 2.0.0 is fixed at 2MHz.

Added in version 2.0.1$nbsp;(Plugin).

long BrickletLEDStrip.getClockFrequency()¶

Returns:	frequency – Type: long, Unit: 1 Hz, Range: [10000 to 2000000], Default: 1666666

Returns the currently used clock frequency as set by setClockFrequency().

Added in version 2.0.1$nbsp;(Plugin).

void BrickletLEDStrip.setChipType(int chip)¶

Parameters:	chip – Type: int, Range: See constants, Default: 2801

Sets the type of the LED driver chip. We currently support the chips

WS2801,
WS2811,
WS2812 / SK6812 / NeoPixel RGB,
SK6812RGBW / NeoPixel RGBW (Chip Type = WS2812),
LPD8806 and
APA102 / DotStar.

The following constants are available for this function:

For chip:

BrickletLEDStrip.CHIP_TYPE_WS2801 = 2801
BrickletLEDStrip.CHIP_TYPE_WS2811 = 2811
BrickletLEDStrip.CHIP_TYPE_WS2812 = 2812
BrickletLEDStrip.CHIP_TYPE_LPD8806 = 8806
BrickletLEDStrip.CHIP_TYPE_APA102 = 102

Added in version 2.0.2$nbsp;(Plugin).

int BrickletLEDStrip.getChipType()¶

Returns:	chip – Type: int, Range: See constants, Default: 2801

Returns the currently used chip type as set by setChipType().

The following constants are available for this function:

For chip:

BrickletLEDStrip.CHIP_TYPE_WS2801 = 2801
BrickletLEDStrip.CHIP_TYPE_WS2811 = 2811
BrickletLEDStrip.CHIP_TYPE_WS2812 = 2812
BrickletLEDStrip.CHIP_TYPE_LPD8806 = 8806
BrickletLEDStrip.CHIP_TYPE_APA102 = 102

Added in version 2.0.2$nbsp;(Plugin).

void BrickletLEDStrip.setRGBWValues(int index, short length, short[] r, short[] g, short[] b, short[] w)¶

Parameters:	index – Type: int, Range: [0 to 239] length – Type: short, Range: [0 to 12] r – Type: short[], Length: 12, Range: [0 to 255] g – Type: short[], Length: 12, Range: [0 to 255] b – Type: short[], Length: 12, Range: [0 to 255] w – Type: short[], Length: 12, Range: [0 to 255]

Sets length RGBW values for the LEDs starting from index.

To make the colors show correctly you need to configure the chip type (setChipType()) and a 4-channel channel mapping (setChannelMapping()) according to the connected LEDs.

The maximum length is 12, the index goes from 0 to 239 and the rgbw values have 8 bits each.

Example: If you set

index to 5,
length to 4,
r to [255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
g to [0, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
b to [0, 0, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0] and
w to [0, 0, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0]

the LED with index 5 will be red, 6 will be green, 7 will be blue and 8 will be white.

Note

Depending on the LED circuitry colors can be permuted.

The colors will be transfered to actual LEDs when the next frame duration ends, see setFrameDuration().

Generic approach:

Set the frame duration to a value that represents the number of frames per second you want to achieve.
Set all of the LED colors for one frame.
Wait for the FrameRenderedCallback callback.
Set all of the LED colors for next frame.
Wait for the FrameRenderedCallback callback.
and so on.

This approach ensures that you can change the LED colors with a fixed frame rate.

The actual number of controllable LEDs depends on the number of free Bricklet ports. See here for more information. A call of setRGBWValues() with index + length above the bounds is ignored completely.

The LPD8806 LED driver chips have 7-bit channels for RGB. Internally the LED Strip Bricklets divides the 8-bit values set using this function by 2 to make them 7-bit. Therefore, you can just use the normal value range (0-255) for LPD8806 LEDs.

The brightness channel of the APA102 LED driver chips has 5-bit. Internally the LED Strip Bricklets divides the 8-bit values set using this function by 8 to make them 5-bit. Therefore, you can just use the normal value range (0-255) for the brightness channel of APA102 LEDs.

Added in version 2.0.6$nbsp;(Plugin).

BrickletLEDStrip.RGBWValues BrickletLEDStrip.getRGBWValues(int index, short length)¶

Parameters:	index – Type: int, Range: [0 to 239] length – Type: short, Range: [0 to 12]
Return Object:	r – Type: short[], Length: 12, Range: [0 to 255] g – Type: short[], Length: 12, Range: [0 to 255] b – Type: short[], Length: 12, Range: [0 to 255] w – Type: short[], Length: 12, Range: [0 to 255]

Returns length RGBW values starting from the given index.

The values are the last values that were set by setRGBWValues().

Added in version 2.0.6$nbsp;(Plugin).

void BrickletLEDStrip.setChannelMapping(short mapping)¶

Parameters:	mapping – Type: short, Range: See constants, Default: 36

Sets the channel mapping for the connected LEDs.

setRGBValues() and setRGBWValues() take the data in RGB(W) order. But the connected LED driver chips might have their 3 or 4 channels in a different order. For example, the WS2801 chips typically use BGR order, the WS2812 chips typically use GRB order and the APA102 chips typically use WBGR order.

The APA102 chips are special. They have three 8-bit channels for RGB and an additional 5-bit channel for the overall brightness of the RGB LED making them 4-channel chips. Internally the brightness channel is the first channel, therefore one of the Wxyz channel mappings should be used. Then the W channel controls the brightness.

If a 3-channel mapping is selected then setRGBValues() has to be used. Calling setRGBWValues() with a 3-channel mapping will produce incorrect results. Vice-versa if a 4-channel mapping is selected then setRGBWValues() has to be used. Calling setRGBValues() with a 4-channel mapping will produce incorrect results.

The following constants are available for this function:

For mapping:

BrickletLEDStrip.CHANNEL_MAPPING_RGB = 6
BrickletLEDStrip.CHANNEL_MAPPING_RBG = 9
BrickletLEDStrip.CHANNEL_MAPPING_BRG = 33
BrickletLEDStrip.CHANNEL_MAPPING_BGR = 36
BrickletLEDStrip.CHANNEL_MAPPING_GRB = 18
BrickletLEDStrip.CHANNEL_MAPPING_GBR = 24
BrickletLEDStrip.CHANNEL_MAPPING_RGBW = 27
BrickletLEDStrip.CHANNEL_MAPPING_RGWB = 30
BrickletLEDStrip.CHANNEL_MAPPING_RBGW = 39
BrickletLEDStrip.CHANNEL_MAPPING_RBWG = 45
BrickletLEDStrip.CHANNEL_MAPPING_RWGB = 54
BrickletLEDStrip.CHANNEL_MAPPING_RWBG = 57
BrickletLEDStrip.CHANNEL_MAPPING_GRWB = 78
BrickletLEDStrip.CHANNEL_MAPPING_GRBW = 75
BrickletLEDStrip.CHANNEL_MAPPING_GBWR = 108
BrickletLEDStrip.CHANNEL_MAPPING_GBRW = 99
BrickletLEDStrip.CHANNEL_MAPPING_GWBR = 120
BrickletLEDStrip.CHANNEL_MAPPING_GWRB = 114
BrickletLEDStrip.CHANNEL_MAPPING_BRGW = 135
BrickletLEDStrip.CHANNEL_MAPPING_BRWG = 141
BrickletLEDStrip.CHANNEL_MAPPING_BGRW = 147
BrickletLEDStrip.CHANNEL_MAPPING_BGWR = 156
BrickletLEDStrip.CHANNEL_MAPPING_BWRG = 177
BrickletLEDStrip.CHANNEL_MAPPING_BWGR = 180
BrickletLEDStrip.CHANNEL_MAPPING_WRBG = 201
BrickletLEDStrip.CHANNEL_MAPPING_WRGB = 198
BrickletLEDStrip.CHANNEL_MAPPING_WGBR = 216
BrickletLEDStrip.CHANNEL_MAPPING_WGRB = 210
BrickletLEDStrip.CHANNEL_MAPPING_WBGR = 228
BrickletLEDStrip.CHANNEL_MAPPING_WBRG = 225

Added in version 2.0.6$nbsp;(Plugin).

short BrickletLEDStrip.getChannelMapping()¶

Returns:	mapping – Type: short, Range: See constants, Default: 36

Returns the currently used channel mapping as set by setChannelMapping().

The following constants are available for this function:

For mapping:

BrickletLEDStrip.CHANNEL_MAPPING_RGB = 6
BrickletLEDStrip.CHANNEL_MAPPING_RBG = 9
BrickletLEDStrip.CHANNEL_MAPPING_BRG = 33
BrickletLEDStrip.CHANNEL_MAPPING_BGR = 36
BrickletLEDStrip.CHANNEL_MAPPING_GRB = 18
BrickletLEDStrip.CHANNEL_MAPPING_GBR = 24
BrickletLEDStrip.CHANNEL_MAPPING_RGBW = 27
BrickletLEDStrip.CHANNEL_MAPPING_RGWB = 30
BrickletLEDStrip.CHANNEL_MAPPING_RBGW = 39
BrickletLEDStrip.CHANNEL_MAPPING_RBWG = 45
BrickletLEDStrip.CHANNEL_MAPPING_RWGB = 54
BrickletLEDStrip.CHANNEL_MAPPING_RWBG = 57
BrickletLEDStrip.CHANNEL_MAPPING_GRWB = 78
BrickletLEDStrip.CHANNEL_MAPPING_GRBW = 75
BrickletLEDStrip.CHANNEL_MAPPING_GBWR = 108
BrickletLEDStrip.CHANNEL_MAPPING_GBRW = 99
BrickletLEDStrip.CHANNEL_MAPPING_GWBR = 120
BrickletLEDStrip.CHANNEL_MAPPING_GWRB = 114
BrickletLEDStrip.CHANNEL_MAPPING_BRGW = 135
BrickletLEDStrip.CHANNEL_MAPPING_BRWG = 141
BrickletLEDStrip.CHANNEL_MAPPING_BGRW = 147
BrickletLEDStrip.CHANNEL_MAPPING_BGWR = 156
BrickletLEDStrip.CHANNEL_MAPPING_BWRG = 177
BrickletLEDStrip.CHANNEL_MAPPING_BWGR = 180
BrickletLEDStrip.CHANNEL_MAPPING_WRBG = 201
BrickletLEDStrip.CHANNEL_MAPPING_WRGB = 198
BrickletLEDStrip.CHANNEL_MAPPING_WGBR = 216
BrickletLEDStrip.CHANNEL_MAPPING_WGRB = 210
BrickletLEDStrip.CHANNEL_MAPPING_WBGR = 228
BrickletLEDStrip.CHANNEL_MAPPING_WBRG = 225

Added in version 2.0.6$nbsp;(Plugin).

Advanced Functions¶

BrickletLEDStrip.Identity BrickletLEDStrip.getIdentity()¶

Return Object:

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]

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 BrickletLEDStrip.enableFrameRenderedCallback()¶

Enables the FrameRenderedCallback callback.

By default the callback is enabled.

Added in version 2.0.6$nbsp;(Plugin).

void BrickletLEDStrip.disableFrameRenderedCallback()¶

Disables the FrameRenderedCallback callback.

By default the callback is enabled.

Added in version 2.0.6$nbsp;(Plugin).

boolean BrickletLEDStrip.isFrameRenderedCallbackEnabled()¶

Returns:	enabled – Type: boolean, Default: true

Returns true if the FrameRenderedCallback callback is enabled, false otherwise.

Added in version 2.0.6$nbsp;(Plugin).

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.

Note

Using callbacks 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.

callback BrickletLEDStrip.FrameRenderedCallback¶

Event Object:	length – Type: int, Range: [0 to 320]

This callback is triggered directly after a new frame is rendered. The parameter is the number of RGB or RGBW LEDs in that frame.

You should send the data for the next frame directly after this callback was triggered.

For an explanation of the general approach see setRGBValues().

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 addFrameRenderedCallback() function. An added callback function can be removed with the removeFrameRenderedCallback() 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[] BrickletLEDStrip.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 BrickletLEDStrip.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:

BrickletLEDStrip.FUNCTION_SET_RGB_VALUES = 1
BrickletLEDStrip.FUNCTION_SET_FRAME_DURATION = 3
BrickletLEDStrip.FUNCTION_SET_CLOCK_FREQUENCY = 7
BrickletLEDStrip.FUNCTION_SET_CHIP_TYPE = 9
BrickletLEDStrip.FUNCTION_SET_RGBW_VALUES = 11
BrickletLEDStrip.FUNCTION_SET_CHANNEL_MAPPING = 13
BrickletLEDStrip.FUNCTION_ENABLE_FRAME_RENDERED_CALLBACK = 15
BrickletLEDStrip.FUNCTION_DISABLE_FRAME_RENDERED_CALLBACK = 16

void BrickletLEDStrip.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.

The following constants are available for this function:

For functionId:

BrickletLEDStrip.FUNCTION_SET_RGB_VALUES = 1
BrickletLEDStrip.FUNCTION_SET_FRAME_DURATION = 3
BrickletLEDStrip.FUNCTION_SET_CLOCK_FREQUENCY = 7
BrickletLEDStrip.FUNCTION_SET_CHIP_TYPE = 9
BrickletLEDStrip.FUNCTION_SET_RGBW_VALUES = 11
BrickletLEDStrip.FUNCTION_SET_CHANNEL_MAPPING = 13
BrickletLEDStrip.FUNCTION_ENABLE_FRAME_RENDERED_CALLBACK = 15
BrickletLEDStrip.FUNCTION_DISABLE_FRAME_RENDERED_CALLBACK = 16

void BrickletLEDStrip.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 BrickletLEDStrip.DEVICE_IDENTIFIER¶

This constant is used to identify a LED Strip 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 BrickletLEDStrip.DEVICE_DISPLAY_NAME¶: This constant represents the human readable name of a LED Strip Bricklet.