Specifications / TCP/IP Protocol / API / Bricks and Bricklets / Bricklets / LED Strip Bricklet 2.0

TCP/IP - LED Strip Bricklet 2.0¶

This is the description of the TCP/IP protocol for the LED Strip Bricklet 2.0. General information and technical specifications for the LED Strip Bricklet 2.0 are summarized in its hardware description.

API¶

A general description of the TCP/IP protocol structure can be found here.

Basic Functions¶

BrickletLEDStripV2.set_led_values_low_level¶

Function ID:	1
Request:	index – Type: uint16, Range: [0 to 6144] value_length – Type: uint16, Range: [0 to 6144] value_chunk_offset – Type: uint16, Range: [0 to 2¹⁶ - 1] value_chunk_data – Type: uint8[58], Range: [0 to 255]
Response:	no response

Sets the RGB(W) values for the LEDs starting from index. You can set at most 2048 RGB values or 1536 RGBW values (6144 byte each).

To make the colors show correctly you need to configure the chip type (see set_chip_type) and a channel mapping (see set_channel_mapping) according to the connected LEDs.

If the channel mapping has 3 colors, you need to give the data in the sequence RGBRGBRGB... if the channel mapping has 4 colors you need to give data in the sequence RGBWRGBWRGBW...

The data is double buffered and the colors will be transfered to the LEDs when the next frame duration ends (see set_frame_duration).

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 CALLBACK_FRAME_STARTED callback.
Set all of the LED colors for next frame.
Wait for the CALLBACK_FRAME_STARTED callback.
And so on.

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

BrickletLEDStripV2.get_led_values_low_level¶

Function ID:	2
Request:	index – Type: uint16, Range: [0 to 6144] length – Type: uint16, Range: [0 to 6144]
Response:	value_length – Type: uint16, Range: [0 to 6144] value_chunk_offset – Type: uint16, Range: [0 to 2¹⁶ - 1] value_chunk_data – Type: uint8[60], Range: [0 to 255]

Returns length RGB(W) values starting from the given index.

If the channel mapping has 3 colors, you will get the data in the sequence RGBRGBRGB... if the channel mapping has 4 colors you will get the data in the sequence RGBWRGBWRGBW... (assuming you start at an index divisible by 3 (RGB) or 4 (RGBW)).

BrickletLEDStripV2.set_frame_duration¶

Function ID:	3
Request:	duration – Type: uint16, Unit: 1 ms, Range: [0 to 2¹⁶ - 1], Default: 100
Response:	no response

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 set_led_values_low_level.

Default value: 100ms (10 frames per second).

BrickletLEDStripV2.get_frame_duration¶

Function ID:	4
Request:	empty payload
Response:	duration – Type: uint16, Unit: 1 ms, Range: [0 to 2¹⁶ - 1], Default: 100

Returns the frame duration as set by set_frame_duration.

BrickletLEDStripV2.get_supply_voltage¶

Function ID:	5
Request:	empty payload
Response:	voltage – Type: uint16, Unit: 1 mV, Range: [0 to 2¹⁶ - 1]

Returns the current supply voltage of the LEDs.

BrickletLEDStripV2.set_clock_frequency¶

Function ID:	7
Request:	frequency – Type: uint32, Unit: 1 Hz, Range: [10000 to 2000000], Default: 1666666
Response:	no response

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 get_clock_frequency.

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.

BrickletLEDStripV2.get_clock_frequency¶

Function ID:	8
Request:	empty payload
Response:	frequency – Type: uint32, Unit: 1 Hz, Range: [10000 to 2000000], Default: 1666666

Returns the currently used clock frequency as set by set_clock_frequency.

BrickletLEDStripV2.set_chip_type¶

Function ID:	9
Request:	chip – Type: uint16, Range: See meanings, Default: 2801
Response:	no response

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),
WS2813 / WS2815 (Chip Type = WS2812)
LPD8806 and
APA102 / DotStar.

The following meanings are defined for the elements of this function:

For chip:

2801 = WS2801
2811 = WS2811
2812 = WS2812
8806 = LPD8806
102 = APA102

BrickletLEDStripV2.get_chip_type¶

Function ID:	10
Request:	empty payload
Response:	chip – Type: uint16, Range: See meanings, Default: 2801

Returns the currently used chip type as set by set_chip_type.

The following meanings are defined for the elements of this function:

For chip:

2801 = WS2801
2811 = WS2811
2812 = WS2812
8806 = LPD8806
102 = APA102

BrickletLEDStripV2.set_channel_mapping¶

Function ID:	11
Request:	mapping – Type: uint8, Range: See meanings, Default: 36
Response:	no response

Sets the channel mapping for the connected LEDs.

If the mapping has 4 colors, the function set_led_values_low_level expects 4 values per pixel and if the mapping has 3 colors it expects 3 values per pixel.

The function always expects the order RGB(W). 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, then 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.

The following meanings are defined for the elements of this function:

For mapping:

6 = RGB
9 = RBG
33 = BRG
36 = BGR
18 = GRB
24 = GBR
27 = RGBW
30 = RGWB
39 = RBGW
45 = RBWG
54 = RWGB
57 = RWBG
78 = GRWB
75 = GRBW
108 = GBWR
99 = GBRW
120 = GWBR
114 = GWRB
135 = BRGW
141 = BRWG
147 = BGRW
156 = BGWR
177 = BWRG
180 = BWGR
201 = WRBG
198 = WRGB
216 = WGBR
210 = WGRB
228 = WBGR
225 = WBRG

BrickletLEDStripV2.get_channel_mapping¶

Function ID:	12
Request:	empty payload
Response:	mapping – Type: uint8, Range: See meanings, Default: 36

Returns the currently used channel mapping as set by set_channel_mapping.

The following meanings are defined for the elements of this function:

For mapping:

6 = RGB
9 = RBG
33 = BRG
36 = BGR
18 = GRB
24 = GBR
27 = RGBW
30 = RGWB
39 = RBGW
45 = RBWG
54 = RWGB
57 = RWBG
78 = GRWB
75 = GRBW
108 = GBWR
99 = GBRW
120 = GWBR
114 = GWRB
135 = BRGW
141 = BRWG
147 = BGRW
156 = BGWR
177 = BWRG
180 = BWGR
201 = WRBG
198 = WRGB
216 = WGBR
210 = WGRB
228 = WBGR
225 = WBRG

Advanced Functions¶

BrickletLEDStripV2.get_spitfp_error_count¶

Function ID:	234
Request:	empty payload
Response:	error_count_ack_checksum – Type: uint32, Range: [0 to 2³² - 1] error_count_message_checksum – Type: uint32, Range: [0 to 2³² - 1] error_count_frame – Type: uint32, Range: [0 to 2³² - 1] error_count_overflow – Type: uint32, 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.

BrickletLEDStripV2.set_status_led_config¶

Function ID:	239
Request:	config – Type: uint8, Range: See meanings, Default: 3
Response:	no response

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 meanings are defined for the elements of this function:

For config:

0 = Off
1 = On
2 = Show Heartbeat
3 = Show Status

BrickletLEDStripV2.get_status_led_config¶

Function ID:	240
Request:	empty payload
Response:	config – Type: uint8, Range: See meanings, Default: 3

Returns the configuration as set by set_status_led_config

The following meanings are defined for the elements of this function:

For config:

0 = Off
1 = On
2 = Show Heartbeat
3 = Show Status

BrickletLEDStripV2.get_chip_temperature¶

Function ID:	242
Request:	empty payload
Response:	temperature – Type: int16, Unit: 1 °C, Range: [-2¹⁵ to 2¹⁵ - 1]

Returns the temperature 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.

BrickletLEDStripV2.reset¶

Function ID:	243
Request:	empty payload
Response:	no response

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!

BrickletLEDStripV2.get_identity¶

Function ID:	255
Request:	empty payload
Response:	uid – Type: char[8] connected_uid – Type: char[8] position – Type: char, Range: ['a' to 'h', 'z'] hardware_version – Type: uint8[3] 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] firmware_version – Type: uint8[3] 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] device_identifier – Type: uint16, 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.

Callback Configuration Functions¶

BrickletLEDStripV2.set_frame_started_callback_configuration¶

Function ID:	13
Request:	enable – Type: bool, Default: true
Response:	no response

Enables/disables the CALLBACK_FRAME_STARTED callback.

BrickletLEDStripV2.get_frame_started_callback_configuration¶

Function ID:	14
Request:	empty payload
Response:	enable – Type: bool, Default: true

Returns the configuration as set by set_frame_started_callback_configuration.

Callbacks¶

BrickletLEDStripV2.CALLBACK_FRAME_STARTED¶

Function ID:	6
Response:	length – Type: uint16, Range: [0 to 6144]

This callback is triggered directly after a new frame render is started. The response value is the number of 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 set_led_values_low_level.

Internal Functions¶

Internal functions are used for maintenance tasks such as flashing a new firmware of changing the UID of a Bricklet. These task should be performed using Brick Viewer instead of using the internal functions directly.

BrickletLEDStripV2.set_bootloader_mode¶

Function ID:	235
Request:	mode – Type: uint8, Range: See meanings
Response:	status – Type: uint8, Range: See meanings

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 meanings are defined for the elements of this function:

For mode:

0 = Bootloader
1 = Firmware
2 = Bootloader Wait For Reboot
3 = Firmware Wait For Reboot
4 = Firmware Wait For Erase And Reboot

For status:

0 = OK
1 = Invalid Mode
2 = No Change
3 = Entry Function Not Present
4 = Device Identifier Incorrect
5 = CRC Mismatch

BrickletLEDStripV2.get_bootloader_mode¶

Function ID:	236
Request:	empty payload
Response:	mode – Type: uint8, Range: See meanings

Returns the current bootloader mode, see set_bootloader_mode.

The following meanings are defined for the elements of this function:

For mode:

0 = Bootloader
1 = Firmware
2 = Bootloader Wait For Reboot
3 = Firmware Wait For Reboot
4 = Firmware Wait For Erase And Reboot

BrickletLEDStripV2.set_write_firmware_pointer¶

Function ID:	237
Request:	pointer – Type: uint32, Unit: 1 B, Range: [0 to 2³² - 1]
Response:	no response

Sets the firmware pointer for write_firmware. 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.

BrickletLEDStripV2.write_firmware¶

Function ID:	238
Request:	data – Type: uint8[64], Range: [0 to 255]
Response:	status – Type: uint8, Range: [0 to 255]

Writes 64 Bytes of firmware at the position as written by set_write_firmware_pointer 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.

BrickletLEDStripV2.write_uid¶

Function ID:	248
Request:	uid – Type: uint32, Range: [0 to 2³² - 1]
Response:	no response

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.

BrickletLEDStripV2.read_uid¶

Function ID:	249
Request:	empty payload
Response:	uid – Type: uint32, Range: [0 to 2³² - 1]

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