Modbus - Outdoor Weather Bricklet

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

API

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

Basic Functions

BrickletOutdoorWeather.get_station_identifiers_low_level
Function ID:
  • 1
Request:
  • empty payload
Response:
  • identifiers_length – Type: uint16, Range: [0 to 256]
  • identifiers_chunk_offset – Type: uint16, Range: [0 to 216 - 1]
  • identifiers_chunk_data – Type: uint8[60], Range: [0 to 255]

Returns the identifiers (number between 0 and 255) of all stations that have been seen since the startup of the Bricklet.

Each station gives itself a random identifier on first startup.

Since firmware version 2.0.2 a station is removed from the list if no data was received for 12 hours.

BrickletOutdoorWeather.get_sensor_identifiers_low_level
Function ID:
  • 2
Request:
  • empty payload
Response:
  • identifiers_length – Type: uint16, Range: [0 to 256]
  • identifiers_chunk_offset – Type: uint16, Range: [0 to 216 - 1]
  • identifiers_chunk_data – Type: uint8[60], Range: [0 to 255]

Returns the identifiers (number between 0 and 255) of all sensors that have been seen since the startup of the Bricklet.

Each sensor gives itself a random identifier on first startup.

Since firmware version 2.0.2 a sensor is removed from the list if no data was received for 12 hours.

BrickletOutdoorWeather.get_station_data
Function ID:
  • 3
Request:
  • identifier – Type: uint8, Range: [0 to 255]
Response:
  • temperature – Type: int16, Unit: 1/10 °C, Range: [-400 to 650]
  • humidity – Type: uint8, Unit: 1 %, Range: [10 to 99]
  • wind_speed – Type: uint32, Unit: 1/10 m/s, Range: [0 to 232 - 1]
  • gust_speed – Type: uint32, Unit: 1/10 m/s, Range: [0 to 232 - 1]
  • rain – Type: uint32, Unit: 1/10 mm, Range: [0 to 232 - 1]
  • wind_direction – Type: uint8, Range: See meanings
  • battery_low – Type: bool
  • last_change – Type: uint16, Unit: 1 s, Range: [0 to 216 - 1]

Returns the last received data for a station with the given identifier. Call get_station_identifiers_low_level for a list of all available identifiers.

The return values are:

  • Temperature,
  • Humidity,
  • Wind Speed,
  • Gust Speed,
  • Rain Fall (accumulated since station power-up),
  • Wind Direction,
  • Battery Low (true if battery is low) and
  • Last Change (seconds since the reception of this data).

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

For wind_direction:

  • 0 = N
  • 1 = NNE
  • 2 = NE
  • 3 = ENE
  • 4 = E
  • 5 = ESE
  • 6 = SE
  • 7 = SSE
  • 8 = S
  • 9 = SSW
  • 10 = SW
  • 11 = WSW
  • 12 = W
  • 13 = WNW
  • 14 = NW
  • 15 = NNW
  • 255 = Error
BrickletOutdoorWeather.get_sensor_data
Function ID:
  • 4
Request:
  • identifier – Type: uint8, Range: [0 to 255]
Response:
  • temperature – Type: int16, Unit: 1/10 °C, Range: [-215 to 215 - 1]
  • humidity – Type: uint8, Unit: 1 %, Range: [0 to 255]
  • last_change – Type: uint16, Unit: 1 s, Range: [0 to 216 - 1]

Returns the last measured data for a sensor with the given identifier. Call get_sensor_identifiers_low_level for a list of all available identifiers.

The return values are:

  • Temperature,
  • Humidity and
  • Last Change (seconds since the last reception of data).

Advanced Functions

BrickletOutdoorWeather.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.

BrickletOutdoorWeather.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
BrickletOutdoorWeather.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
BrickletOutdoorWeather.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.

BrickletOutdoorWeather.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!

BrickletOutdoorWeather.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

BrickletOutdoorWeather.set_station_callback_configuration
Function ID:
  • 5
Request:
  • enable_callback – Type: bool, Default: false
Response:
  • no response

Turns callback for station data on or off.

BrickletOutdoorWeather.get_station_callback_configuration
Function ID:
  • 6
Request:
  • empty payload
Response:
  • enable_callback – Type: bool, Default: false

Returns the configuration as set by set_station_callback_configuration.

BrickletOutdoorWeather.set_sensor_callback_configuration
Function ID:
  • 7
Request:
  • enable_callback – Type: bool, Default: false
Response:
  • no response

Turns callback for sensor data on or off.

BrickletOutdoorWeather.get_sensor_callback_configuration
Function ID:
  • 8
Request:
  • empty payload
Response:
  • enable_callback – Type: bool, Default: false

Returns the configuration as set by set_sensor_callback_configuration.

Callbacks

BrickletOutdoorWeather.CALLBACK_STATION_DATA
Function ID:
  • 9
Response:
  • identifier – Type: uint8, Range: [0 to 255]
  • temperature – Type: int16, Unit: 1/10 °C, Range: [-400 to 650]
  • humidity – Type: uint8, Unit: 1 %, Range: [10 to 99]
  • wind_speed – Type: uint32, Unit: 1/10 m/s, Range: [0 to 232 - 1]
  • gust_speed – Type: uint32, Unit: 1/10 m/s, Range: [0 to 232 - 1]
  • rain – Type: uint32, Unit: 1/10 mm, Range: [0 to 232 - 1]
  • wind_direction – Type: uint8, Range: See meanings
  • battery_low – Type: bool

Reports the station data every time a new data packet is received. See get_station_data for information about the data.

For each station the callback will be triggered about every 45 seconds.

Turn the callback on/off with set_station_callback_configuration (by default it is turned off).

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

For wind_direction:

  • 0 = N
  • 1 = NNE
  • 2 = NE
  • 3 = ENE
  • 4 = E
  • 5 = ESE
  • 6 = SE
  • 7 = SSE
  • 8 = S
  • 9 = SSW
  • 10 = SW
  • 11 = WSW
  • 12 = W
  • 13 = WNW
  • 14 = NW
  • 15 = NNW
  • 255 = Error
BrickletOutdoorWeather.CALLBACK_SENSOR_DATA
Function ID:
  • 10
Response:
  • identifier – Type: uint8, Range: [0 to 255]
  • temperature – Type: int16, Unit: 1/10 °C, Range: [-215 to 215 - 1]
  • humidity – Type: uint8, Unit: 1 %, Range: [0 to 255]

Reports the sensor data every time a new data packet is received. See get_sensor_data for information about the data.

For each sensor the callback will be called about every 45 seconds.

Turn the callback on/off with set_sensor_callback_configuration (by default it is turned 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.

BrickletOutdoorWeather.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
BrickletOutdoorWeather.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
BrickletOutdoorWeather.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.

BrickletOutdoorWeather.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.

BrickletOutdoorWeather.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.

BrickletOutdoorWeather.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.