Modbus - Dual Button Bricklet 2.0

This is the description of the Modbus protocol for the Dual Button Bricklet 2.0. General information and technical specifications for the Dual Button Bricklet 2.0 are summarized in its hardware description.

API

A general description of the Modbus protocol structure can be found here.

Basic Functions

BrickletDualButtonV2.set_led_state
Function ID:
  • 1
Request:
  • led_l – Type: uint8, Range: See meanings, Default: 1
  • led_r – Type: uint8, Range: See meanings, Default: 1
Response:
  • no response

Sets the state of the LEDs. Possible states are:

  • 0 = AutoToggleOn: Enables auto toggle with initially enabled LED.
  • 1 = AutoToggleOff: Activates auto toggle with initially disabled LED.
  • 2 = On: Enables LED (auto toggle is disabled).
  • 3 = Off: Disables LED (auto toggle is disabled).

In auto toggle mode the LED is toggled automatically at each press of a button.

If you just want to set one of the LEDs and don't know the current state of the other LED, you can get the state with get_led_state or you can use set_selected_led_state.

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

For led_l:

  • 0 = Auto Toggle On
  • 1 = Auto Toggle Off
  • 2 = On
  • 3 = Off

For led_r:

  • 0 = Auto Toggle On
  • 1 = Auto Toggle Off
  • 2 = On
  • 3 = Off
BrickletDualButtonV2.get_led_state
Function ID:
  • 2
Request:
  • empty payload
Response:
  • led_l – Type: uint8, Range: See meanings, Default: 1
  • led_r – Type: uint8, Range: See meanings, Default: 1

Returns the current state of the LEDs, as set by set_led_state.

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

For led_l:

  • 0 = Auto Toggle On
  • 1 = Auto Toggle Off
  • 2 = On
  • 3 = Off

For led_r:

  • 0 = Auto Toggle On
  • 1 = Auto Toggle Off
  • 2 = On
  • 3 = Off
BrickletDualButtonV2.get_button_state
Function ID:
  • 3
Request:
  • empty payload
Response:
  • button_l – Type: uint8, Range: See meanings
  • button_r – Type: uint8, Range: See meanings

Returns the current state for both buttons. Possible states are:

  • 0 = pressed
  • 1 = released

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

For button_l:

  • 0 = Pressed
  • 1 = Released

For button_r:

  • 0 = Pressed
  • 1 = Released

Advanced Functions

BrickletDualButtonV2.set_selected_led_state
Function ID:
  • 5
Request:
  • led – Type: uint8, Range: See meanings
  • state – Type: uint8, Range: See meanings
Response:
  • no response

Sets the state of the selected LED.

The other LED remains untouched.

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

For led:

  • 0 = Left
  • 1 = Right

For state:

  • 0 = Auto Toggle On
  • 1 = Auto Toggle Off
  • 2 = On
  • 3 = Off
BrickletDualButtonV2.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.

BrickletDualButtonV2.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
BrickletDualButtonV2.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
BrickletDualButtonV2.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.

BrickletDualButtonV2.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!

BrickletDualButtonV2.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

BrickletDualButtonV2.set_state_changed_callback_configuration
Function ID:
  • 6
Request:
  • enabled – Type: bool, Default: false
Response:
  • no response

If you enable this callback, the CALLBACK_STATE_CHANGED callback is triggered every time a button is pressed/released

BrickletDualButtonV2.get_state_changed_callback_configuration
Function ID:
  • 7
Request:
  • empty payload
Response:
  • enabled – Type: bool, Default: false

Returns the configuration as set by set_state_changed_callback_configuration.

Callbacks

BrickletDualButtonV2.CALLBACK_STATE_CHANGED
Function ID:
  • 4
Response:
  • button_l – Type: uint8, Range: See meanings
  • button_r – Type: uint8, Range: See meanings
  • led_l – Type: uint8, Range: See meanings
  • led_r – Type: uint8, Range: See meanings

This callback is called whenever a button is pressed.

Possible states for buttons are:

  • 0 = pressed
  • 1 = released

Possible states for LEDs are:

  • 0 = AutoToggleOn: Auto toggle enabled and LED on.
  • 1 = AutoToggleOff: Auto toggle enabled and LED off.
  • 2 = On: LED on (auto toggle is disabled).
  • 3 = Off: LED off (auto toggle is disabled).

This callback can be enabled with set_state_changed_callback_configuration.

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

For button_l:

  • 0 = Pressed
  • 1 = Released

For button_r:

  • 0 = Pressed
  • 1 = Released

For led_l:

  • 0 = Auto Toggle On
  • 1 = Auto Toggle Off
  • 2 = On
  • 3 = Off

For led_r:

  • 0 = Auto Toggle On
  • 1 = Auto Toggle Off
  • 2 = On
  • 3 = Off

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.

BrickletDualButtonV2.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
BrickletDualButtonV2.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
BrickletDualButtonV2.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.

BrickletDualButtonV2.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.

BrickletDualButtonV2.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.

BrickletDualButtonV2.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.