Modbus - DMX Bricklet¶

Basic Functions¶

BrickletDMX.set_dmx_mode¶

Function ID:	1
Request:	dmx_mode – Type: uint8, Range: See meanings, Default: 0
Response:	no response

Sets the DMX mode to either master or slave.

Calling this function sets frame number to 0.

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

For dmx_mode:

• 0 = Master
• 1 = Slave

BrickletDMX.get_dmx_mode¶

Function ID:	2
Request:	empty payload
Response:	dmx_mode – Type: uint8, Range: See meanings, Default: 0

Returns the DMX mode, as set by set_dmx_mode.

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

For dmx_mode:

• 0 = Master
• 1 = Slave

BrickletDMX.write_frame_low_level¶

Function ID:	3
Request:	frame_length – Type: uint16, Range: [0 to 29] frame_chunk_offset – Type: uint16, Range: [0 to 216 - 1] frame_chunk_data – Type: uint8[60], Range: [0 to 255]
Response:	no response

Writes a DMX frame. The maximum frame size is 512 byte. Each byte represents one channel.

The next frame can be written after the CALLBACK_FRAME_STARTED callback was called. The frame is double buffered, so a new frame can be written as soon as the writing of the prior frame starts.

The data will be transfered 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 channels for first frame.
• Wait for the CALLBACK_FRAME_STARTED callback.
• Set channels for next frame.
• Wait for the CALLBACK_FRAME_STARTED callback.
• and so on.

This approach ensures that you can set new DMX data with a fixed frame rate.

This function can only be called in master mode.

BrickletDMX.read_frame_low_level¶

Function ID:	4
Request:	empty payload
Response:	frame_length – Type: uint16, Range: [0 to 29] frame_chunk_offset – Type: uint16, Range: [0 to 216 - 1] frame_chunk_data – Type: uint8[56], Range: [0 to 255] frame_number – Type: uint32, Range: [0 to 232 - 1]

Returns the last frame that was written by the DMX master. The size of the array is equivalent to the number of channels in the frame. Each byte represents one channel.

The next frame is available after the CALLBACK_FRAME_AVAILABLE callback was called.

Generic approach:

• Call read_frame_low_level to get first frame.
• Wait for the CALLBACK_FRAME_AVAILABLE callback.
• Call read_frame_low_level to get second frame.
• Wait for the CALLBACK_FRAME_AVAILABLE callback.
• and so on.

Instead of polling this function you can also use the CALLBACK_FRAME_LOW_LEVEL callback. You can enable it with set_frame_callback_config.

The frame number starts at 0 and it is increased by one with each received frame.

This function can only be called in slave mode.

BrickletDMX.set_frame_duration¶

Function ID:	5
Request:	frame_duration – Type: uint16, Unit: 1 ms, Range: [0 to 216 - 1], Default: 100
Response:	no response

Sets the duration of a frame.

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

If you always want to send a frame as fast as possible you can set this value to 0.

This setting is only used in master mode.

BrickletDMX.get_frame_duration¶

Function ID:	6
Request:	empty payload
Response:	frame_duration – Type: uint16, Unit: 1 ms, Range: [0 to 216 - 1], Default: 100

Returns the frame duration as set by set_frame_duration.

Advanced Functions¶

BrickletDMX.get_frame_error_count¶

Function ID:	7
Request:	empty payload
Response:	overrun_error_count – Type: uint32, Range: [0 to 232 - 1] framing_error_count – Type: uint32, Range: [0 to 232 - 1]

Returns the current number of overrun and framing errors.

BrickletDMX.set_communication_led_config¶

Function ID:	8
Request:	config – Type: uint8, Range: See meanings, Default: 3
Response:	no response

Sets the communication LED configuration. By default the LED shows communication traffic, 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 off.

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

For config:

• 0 = Off
• 1 = On
• 2 = Show Heartbeat
• 3 = Show Communication

BrickletDMX.get_communication_led_config¶

Function ID:	9
Request:	empty payload
Response:	config – Type: uint8, Range: See meanings, Default: 3

Returns the configuration as set by set_communication_led_config

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

For config:

• 0 = Off
• 1 = On
• 2 = Show Heartbeat
• 3 = Show Communication

BrickletDMX.set_error_led_config¶

Function ID:	10
Request:	config – Type: uint8, Range: See meanings, Default: 3
Response:	no response

Sets the error LED configuration.

By default the error LED turns on if there is any error (see CALLBACK_FRAME_ERROR_COUNT callback). If you call this function with the Show-Error option again, the LED will turn off until the next error occurs.

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

If the Bricklet is in bootloader mode, the LED is off.

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

For config:

• 0 = Off
• 1 = On
• 2 = Show Heartbeat
• 3 = Show Error

BrickletDMX.get_error_led_config¶

Function ID:	11
Request:	empty payload
Response:	config – Type: uint8, Range: See meanings, Default: 3

Returns the configuration as set by set_error_led_config.

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

For config:

• 0 = Off
• 1 = On
• 2 = Show Heartbeat
• 3 = Show Error

BrickletDMX.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.

BrickletDMX.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

BrickletDMX.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

BrickletDMX.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.

BrickletDMX.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!

BrickletDMX.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¶

BrickletDMX.set_frame_callback_config¶

Function ID:	12
Request:	frame_started_callback_enabled – Type: bool, Default: true frame_available_callback_enabled – Type: bool, Default: true frame_callback_enabled – Type: bool, Default: false frame_error_count_callback_enabled – Type: bool, Default: false
Response:	no response

Enables/Disables the different callbacks. By default the CALLBACK_FRAME_STARTED callback and CALLBACK_FRAME_AVAILABLE callback are enabled while the CALLBACK_FRAME_LOW_LEVEL callback and CALLBACK_FRAME_ERROR_COUNT callback are disabled.

If you want to use the CALLBACK_FRAME_LOW_LEVEL callback you can enable it and disable the CALLBACK_FRAME_AVAILABLE callback at the same time. It becomes redundant in this case.

BrickletDMX.get_frame_callback_config¶

Function ID:	13
Request:	empty payload
Response:	frame_started_callback_enabled – Type: bool, Default: true frame_available_callback_enabled – Type: bool, Default: true frame_callback_enabled – Type: bool, Default: false frame_error_count_callback_enabled – Type: bool, Default: false

Returns the frame callback config as set by set_frame_callback_config.

Callbacks¶

BrickletDMX.CALLBACK_FRAME_STARTED¶

Function ID:	14
Response:	empty payload

This callback is triggered as soon as a new frame write is started. You should send the data for the next frame directly after this callback was triggered.

For an explanation of the general approach see write_frame_low_level.

This callback can be enabled via set_frame_callback_config.

This callback can only be triggered in master mode.

BrickletDMX.CALLBACK_FRAME_AVAILABLE¶

Function ID:	15
Response:	frame_number – Type: uint32, Range: [0 to 232 - 1]

This callback is triggered in slave mode when a new frame was received from the DMX master and it can be read out. You have to read the frame before the master has written the next frame, see read_frame_low_level for more details.

The parameter is the frame number, it is increased by one with each received frame.

This callback can be enabled via set_frame_callback_config.

This callback can only be triggered in slave mode.

BrickletDMX.CALLBACK_FRAME_LOW_LEVEL¶

Function ID:	16
Response:	frame_length – Type: uint16, Range: [0 to 29] frame_chunk_offset – Type: uint16, Range: [0 to 216 - 1] frame_chunk_data – Type: uint8[56], Range: [0 to 255] frame_number – Type: uint32, Range: [0 to 232 - 1]

This callback is called as soon as a new frame is available (written by the DMX master).

The size of the array is equivalent to the number of channels in the frame. Each byte represents one channel.

This callback can be enabled via set_frame_callback_config.

This callback can only be triggered in slave mode.

BrickletDMX.CALLBACK_FRAME_ERROR_COUNT¶

Function ID:	17
Response:	overrun_error_count – Type: uint32, Range: [0 to 232 - 1] framing_error_count – Type: uint32, Range: [0 to 232 - 1]

This callback is called if a new error occurs. It returns the current overrun and framing error count.

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.

BrickletDMX.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

BrickletDMX.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

BrickletDMX.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.

BrickletDMX.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.

BrickletDMX.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.

BrickletDMX.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.