MATLAB/Octave - RGB LED Matrix Bricklet

This is the description of the MATLAB/Octave API bindings for the RGB LED Matrix Bricklet. General information and technical specifications for the RGB LED Matrix 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).

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 BrickletRGBLEDMatrix(String uid, IPConnection ipcon)
Parameters:
  • uid – Type: String
  • ipcon – Type: IPConnection
Returns:
  • rgbLEDMatrix – Type: BrickletRGBLEDMatrix

Creates an object with the unique device ID uid.

In MATLAB:

import com.tinkerforge.BrickletRGBLEDMatrix;

rgbLEDMatrix = BrickletRGBLEDMatrix('YOUR_DEVICE_UID', ipcon);

In Octave:

rgbLEDMatrix = java_new("com.tinkerforge.BrickletRGBLEDMatrix", "YOUR_DEVICE_UID", ipcon);

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

void BrickletRGBLEDMatrix.setRed(int[] red)
Parameters:
  • red – Type: int[], Length: 64, Range: [0 to 255]

Sets the 64 red LED values of the matrix.

int[] BrickletRGBLEDMatrix.getRed()
Returns:
  • red – Type: int[], Length: 64, Range: [0 to 255]

Returns the red LED values as set by setRed().

void BrickletRGBLEDMatrix.setGreen(int[] green)
Parameters:
  • green – Type: int[], Length: 64, Range: [0 to 255]

Sets the 64 green LED values of the matrix.

int[] BrickletRGBLEDMatrix.getGreen()
Returns:
  • green – Type: int[], Length: 64, Range: [0 to 255]

Returns the green LED values as set by setGreen().

void BrickletRGBLEDMatrix.setBlue(int[] blue)
Parameters:
  • blue – Type: int[], Length: 64, Range: [0 to 255]

Sets the 64 blue LED values of the matrix.

int[] BrickletRGBLEDMatrix.getBlue()
Returns:
  • blue – Type: int[], Length: 64, Range: [0 to 255]

Returns the blue LED values as set by setBlue().

void BrickletRGBLEDMatrix.setFrameDuration(int frameDuration)
Parameters:
  • frameDuration – Type: int, Range: [0 to 216 - 1]

Sets the frame duration in ms.

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

Set this value to 0 to turn the automatic frame write mechanism off.

Approach:

For frame duration of 0 see drawFrame().

Default value: 0 = off.

int BrickletRGBLEDMatrix.getFrameDuration()
Returns:
  • frameDuration – Type: int, Range: [0 to 216 - 1]

Returns the frame duration in ms as set by setFrameDuration().

void BrickletRGBLEDMatrix.drawFrame()

If you set the frame duration to 0 (see setFrameDuration()), you can use this function to transfer the frame to the matrix.

Approach:

Advanced Functions

int BrickletRGBLEDMatrix.getSupplyVoltage()
Returns:
  • voltage – Type: int, Range: [0 to 216 - 1]

Returns the current supply voltage of the Bricklet. The voltage is given in mV.

int[] BrickletRGBLEDMatrix.getAPIVersion()
Returns:
  • apiVersion – Type: int[], Length: 3, Range: [0 to 255]

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.

boolean BrickletRGBLEDMatrix.getResponseExpected(int functionId)
Parameters:
  • functionId – Type: int, 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 send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

  • BrickletRGBLEDMatrix.FUNCTION_SET_RED = 1
  • BrickletRGBLEDMatrix.FUNCTION_SET_GREEN = 3
  • BrickletRGBLEDMatrix.FUNCTION_SET_BLUE = 5
  • BrickletRGBLEDMatrix.FUNCTION_SET_FRAME_DURATION = 7
  • BrickletRGBLEDMatrix.FUNCTION_DRAW_FRAME = 9
  • BrickletRGBLEDMatrix.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletRGBLEDMatrix.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletRGBLEDMatrix.FUNCTION_RESET = 243
  • BrickletRGBLEDMatrix.FUNCTION_WRITE_UID = 248
void BrickletRGBLEDMatrix.setResponseExpected(int functionId, boolean responseExpected)
Parameters:
  • functionId – Type: int, 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 send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

  • BrickletRGBLEDMatrix.FUNCTION_SET_RED = 1
  • BrickletRGBLEDMatrix.FUNCTION_SET_GREEN = 3
  • BrickletRGBLEDMatrix.FUNCTION_SET_BLUE = 5
  • BrickletRGBLEDMatrix.FUNCTION_SET_FRAME_DURATION = 7
  • BrickletRGBLEDMatrix.FUNCTION_DRAW_FRAME = 9
  • BrickletRGBLEDMatrix.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletRGBLEDMatrix.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletRGBLEDMatrix.FUNCTION_RESET = 243
  • BrickletRGBLEDMatrix.FUNCTION_WRITE_UID = 248
void BrickletRGBLEDMatrix.setResponseExpectedAll(boolean responseExpected)
Parameters:
  • responseExpected – Type: boolean

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

BrickletRGBLEDMatrix.SPITFPErrorCount BrickletRGBLEDMatrix.getSPITFPErrorCount()
Return Object:
  • errorCountAckChecksum – Type: long, Range: [0 to 232 - 1]
  • errorCountMessageChecksum – Type: long, Range: [0 to 232 - 1]
  • errorCountFrame – Type: long, Range: [0 to 232 - 1]
  • errorCountOverflow – Type: long, Range: [0 to 232 - 1]

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

  • ACK checksum errors,
  • message checksum errors,
  • framing errors and
  • overflow errors.

The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.

int BrickletRGBLEDMatrix.setBootloaderMode(int mode)
Parameters:
  • mode – Type: int, Range: See constants
Returns:
  • status – Type: int, Range: See constants

Sets the bootloader mode and returns the status after the requested mode change was instigated.

You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

The following constants are available for this function:

For mode:

  • BrickletRGBLEDMatrix.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletRGBLEDMatrix.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletRGBLEDMatrix.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletRGBLEDMatrix.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletRGBLEDMatrix.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

For status:

  • BrickletRGBLEDMatrix.BOOTLOADER_STATUS_OK = 0
  • BrickletRGBLEDMatrix.BOOTLOADER_STATUS_INVALID_MODE = 1
  • BrickletRGBLEDMatrix.BOOTLOADER_STATUS_NO_CHANGE = 2
  • BrickletRGBLEDMatrix.BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BrickletRGBLEDMatrix.BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BrickletRGBLEDMatrix.BOOTLOADER_STATUS_CRC_MISMATCH = 5
int BrickletRGBLEDMatrix.getBootloaderMode()
Returns:
  • mode – Type: int, Range: See constants

Returns the current bootloader mode, see setBootloaderMode().

The following constants are available for this function:

For mode:

  • BrickletRGBLEDMatrix.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletRGBLEDMatrix.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletRGBLEDMatrix.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletRGBLEDMatrix.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletRGBLEDMatrix.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
void BrickletRGBLEDMatrix.setWriteFirmwarePointer(long pointer)
Parameters:
  • pointer – Type: long, Range: [0 to 232 - 1]

Sets the firmware pointer for writeFirmware(). The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

int BrickletRGBLEDMatrix.writeFirmware(int[] data)
Parameters:
  • data – Type: int[], Length: 64, Range: [0 to 255]
Returns:
  • status – Type: int, Range: [0 to 255]

Writes 64 Bytes of firmware at the position as written by setWriteFirmwarePointer() before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

void BrickletRGBLEDMatrix.setStatusLEDConfig(int config)
Parameters:
  • config – Type: int, Range: See constants

Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.

The following constants are available for this function:

For config:

  • BrickletRGBLEDMatrix.STATUS_LED_CONFIG_OFF = 0
  • BrickletRGBLEDMatrix.STATUS_LED_CONFIG_ON = 1
  • BrickletRGBLEDMatrix.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletRGBLEDMatrix.STATUS_LED_CONFIG_SHOW_STATUS = 3
int BrickletRGBLEDMatrix.getStatusLEDConfig()
Returns:
  • config – Type: int, Range: See constants

Returns the configuration as set by setStatusLEDConfig()

The following constants are available for this function:

For config:

  • BrickletRGBLEDMatrix.STATUS_LED_CONFIG_OFF = 0
  • BrickletRGBLEDMatrix.STATUS_LED_CONFIG_ON = 1
  • BrickletRGBLEDMatrix.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletRGBLEDMatrix.STATUS_LED_CONFIG_SHOW_STATUS = 3
int BrickletRGBLEDMatrix.getChipTemperature()
Returns:
  • temperature – Type: int, Range: [-215 to 215 - 1]

Returns the temperature in °C as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.

void BrickletRGBLEDMatrix.reset()

Calling this function will reset the Bricklet. All configurations will be lost.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!

void BrickletRGBLEDMatrix.writeUID(long uid)
Parameters:
  • uid – Type: long, Range: [0 to 232 - 1]

Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.

We recommend that you use Brick Viewer to change the UID.

long BrickletRGBLEDMatrix.readUID()
Returns:
  • uid – Type: long, Range: [0 to 232 - 1]

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

BrickletRGBLEDMatrix.Identity BrickletRGBLEDMatrix.getIdentity()
Return Object:
  • uid – Type: String, Length: up to 8
  • connectedUid – Type: String, Length: up to 8
  • position – Type: char
  • hardwareVersion – Type: int[], Length: 3, Range: [0 to 255]
  • firmwareVersion – Type: int[], Length: 3, 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' or 'd'.

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

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 BrickletRGBLEDMatrix.FrameStartedCallback
Event Object:
  • frameNumber – Type: long, Range: [0 to 232 - 1]

This callback is triggered as soon as a new frame write is started. The LED values are double buffered, so you can send the LED values for the next frame directly after this callback is triggered.

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 addFrameStartedCallback() function. An added callback function can be removed with the removeFrameStartedCallback() function.

Constants

int BrickletRGBLEDMatrix.DEVICE_IDENTIFIER

This constant is used to identify a RGB LED Matrix 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 BrickletRGBLEDMatrix.DEVICE_DISPLAY_NAME

This constant represents the human readable name of a RGB LED Matrix Bricklet.