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 -- uint16
  • value_length -- uint16
  • value_chunk_offset -- uint16
  • value_chunk_data -- uint8[58]
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.

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 -- uint16
  • length -- uint16
Response:
  • value_length -- uint16
  • value_chunk_offset -- uint16
  • value_chunk_data -- uint8[60]

Returns the RGB(W) values as set by set_led_values_low_level.

BrickletLEDStripV2.set_frame_duration
Function ID:

3

Request:
  • duration -- uint16
Response:

no response

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).

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 -- uint16

Returns the frame duration in ms as set by set_frame_duration.

BrickletLEDStripV2.get_supply_voltage
Function ID:

5

Request:

empty payload

Response:
  • voltage -- uint16

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

BrickletLEDStripV2.set_clock_frequency
Function ID:

7

Request:
  • frequency -- uint32
Response:

no response

Sets the frequency of the clock in Hz. The range is 10000Hz (10kHz) up to 2000000Hz (2MHz).

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.

The default value is 1.66MHz.

BrickletLEDStripV2.get_clock_frequency
Function ID:

8

Request:

empty payload

Response:
  • frequency -- uint32

Returns the currently used clock frequency as set by set_clock_frequency.

BrickletLEDStripV2.set_chip_type
Function ID:

9

Request:
  • chip -- uint16
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),
  • LPD8806 and
  • APA102 / DotStar.

The default value is WS2801 (2801).

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

  • 2801: ws2801, for chip
  • 2811: ws2811, for chip
  • 2812: ws2812, for chip
  • 8806: lpd8806, for chip
  • 102: apa102, for chip
BrickletLEDStripV2.get_chip_type
Function ID:

10

Request:

empty payload

Response:
  • chip -- uint16

Returns the currently used chip type as set by set_chip_type.

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

  • 2801: ws2801, for chip
  • 2811: ws2811, for chip
  • 2812: ws2812, for chip
  • 8806: lpd8806, for chip
  • 102: apa102, for chip
BrickletLEDStripV2.set_channel_mapping
Function ID:

11

Request:
  • mapping -- uint8
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 default value is BGR (36).

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

  • 6: rgb, for mapping
  • 9: rbg, for mapping
  • 33: brg, for mapping
  • 36: bgr, for mapping
  • 18: grb, for mapping
  • 24: gbr, for mapping
  • 27: rgbw, for mapping
  • 30: rgwb, for mapping
  • 39: rbgw, for mapping
  • 45: rbwg, for mapping
  • 54: rwgb, for mapping
  • 57: rwbg, for mapping
  • 78: grwb, for mapping
  • 75: grbw, for mapping
  • 108: gbwr, for mapping
  • 99: gbrw, for mapping
  • 120: gwbr, for mapping
  • 114: gwrb, for mapping
  • 135: brgw, for mapping
  • 141: brwg, for mapping
  • 147: bgrw, for mapping
  • 156: bgwr, for mapping
  • 177: bwrg, for mapping
  • 180: bwgr, for mapping
  • 201: wrbg, for mapping
  • 198: wrgb, for mapping
  • 216: wgbr, for mapping
  • 210: wgrb, for mapping
  • 228: wbgr, for mapping
  • 225: wbrg, for mapping
BrickletLEDStripV2.get_channel_mapping
Function ID:

12

Request:

empty payload

Response:
  • mapping -- uint8

Returns the currently used channel mapping as set by set_channel_mapping.

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

  • 6: rgb, for mapping
  • 9: rbg, for mapping
  • 33: brg, for mapping
  • 36: bgr, for mapping
  • 18: grb, for mapping
  • 24: gbr, for mapping
  • 27: rgbw, for mapping
  • 30: rgwb, for mapping
  • 39: rbgw, for mapping
  • 45: rbwg, for mapping
  • 54: rwgb, for mapping
  • 57: rwbg, for mapping
  • 78: grwb, for mapping
  • 75: grbw, for mapping
  • 108: gbwr, for mapping
  • 99: gbrw, for mapping
  • 120: gwbr, for mapping
  • 114: gwrb, for mapping
  • 135: brgw, for mapping
  • 141: brwg, for mapping
  • 147: bgrw, for mapping
  • 156: bgwr, for mapping
  • 177: bwrg, for mapping
  • 180: bwgr, for mapping
  • 201: wrbg, for mapping
  • 198: wrgb, for mapping
  • 216: wgbr, for mapping
  • 210: wgrb, for mapping
  • 228: wbgr, for mapping
  • 225: wbrg, for mapping

Advanced Functions

BrickletLEDStripV2.get_spitfp_error_count
Function ID:

234

Request:

empty payload

Response:
  • error_count_ack_checksum -- uint32
  • error_count_message_checksum -- uint32
  • error_count_frame -- uint32
  • error_count_overflow -- uint32

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_bootloader_mode
Function ID:

235

Request:
  • mode -- uint8
Response:
  • status -- uint8

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 parameters of this function:

  • 0: bootloader, for mode
  • 1: firmware, for mode
  • 2: bootloader wait for reboot, for mode
  • 3: firmware wait for reboot, for mode
  • 4: firmware wait for erase and reboot, for mode
  • 0: ok, for status
  • 1: invalid mode, for status
  • 2: no change, for status
  • 3: entry function not present, for status
  • 4: device identifier incorrect, for status
  • 5: crc mismatch, for status
BrickletLEDStripV2.get_bootloader_mode
Function ID:

236

Request:

empty payload

Response:
  • mode -- uint8

Returns the current bootloader mode, see set_bootloader_mode.

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

  • 0: bootloader, for mode
  • 1: firmware, for mode
  • 2: bootloader wait for reboot, for mode
  • 3: firmware wait for reboot, for mode
  • 4: firmware wait for erase and reboot, for mode
BrickletLEDStripV2.set_write_firmware_pointer
Function ID:

237

Request:
  • pointer -- uint32
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 -- uint8[64]
Response:
  • status -- uint8

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.set_status_led_config
Function ID:

239

Request:
  • config -- uint8
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 parameters of this function:

  • 0: off, for config
  • 1: on, for config
  • 2: show heartbeat, for config
  • 3: show status, for config
BrickletLEDStripV2.get_status_led_config
Function ID:

240

Request:

empty payload

Response:
  • config -- uint8

Returns the configuration as set by set_status_led_config

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

  • 0: off, for config
  • 1: on, for config
  • 2: show heartbeat, for config
  • 3: show status, for config
BrickletLEDStripV2.get_chip_temperature
Function ID:

242

Request:

empty payload

Response:
  • temperature -- int16

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.

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.write_uid
Function ID:

248

Request:
  • uid -- uint32
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 -- uint32

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

BrickletLEDStripV2.get_identity
Function ID:

255

Request:

empty payload

Response:
  • uid -- char[8]
  • connected_uid -- char[8]
  • position -- char
  • hardware_version -- uint8[3]
  • firmware_version -- uint8[3]
  • device_identifier -- uint16

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

Callback Configuration Functions

BrickletLEDStripV2.set_frame_started_callback_configuration
Function ID:

13

Request:
  • enable -- bool
Response:

no response

Enables/disables the CALLBACK_FRAME_STARTED callback.

By default the callback is enabled.

BrickletLEDStripV2.get_frame_started_callback_configuration
Function ID:

14

Request:

empty payload

Response:
  • enable -- bool

Returns the configuration as set by set_frame_started_callback_configuration.

Callbacks

BrickletLEDStripV2.CALLBACK_FRAME_STARTED
Function ID:

6

Response:
  • length -- uint16

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.