Python - CO2 Bricklet 2.0

This is the description of the Python API bindings for the CO2 Bricklet 2.0. General information and technical specifications for the CO2 Bricklet 2.0 are summarized in its hardware description.

An installation guide for the Python API bindings is part of their general description.

Examples

The example code below is Public Domain (CC0 1.0).

Simple

Download (example_simple.py)

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#!/usr/bin/env python
# -*- coding: utf-8 -*-

HOST = "localhost"
PORT = 4223
UID = "XYZ" # Change XYZ to the UID of your CO2 Bricklet 2.0

from tinkerforge.ip_connection import IPConnection
from tinkerforge.bricklet_co2_v2 import BrickletCO2V2

if __name__ == "__main__":
    ipcon = IPConnection() # Create IP connection
    co2 = BrickletCO2V2(UID, ipcon) # Create device object

    ipcon.connect(HOST, PORT) # Connect to brickd
    # Don't use device before ipcon is connected

    # Get current all values
    co2_concentration, temperature, humidity = co2.get_all_values()

    print("CO2 Concentration: " + str(co2_concentration) + " ppm")
    print("Temperature: " + str(temperature/100.0) + " °C")
    print("Humidity: " + str(humidity/100.0) + " %RH")

    raw_input("Press key to exit\n") # Use input() in Python 3
    ipcon.disconnect()

Callback

Download (example_callback.py)

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#!/usr/bin/env python
# -*- coding: utf-8 -*-

HOST = "localhost"
PORT = 4223
UID = "XYZ" # Change XYZ to the UID of your CO2 Bricklet 2.0

from tinkerforge.ip_connection import IPConnection
from tinkerforge.bricklet_co2_v2 import BrickletCO2V2

# Callback function for all values callback
def cb_all_values(co2_concentration, temperature, humidity):
    print("CO2 Concentration: " + str(co2_concentration) + " ppm")
    print("Temperature: " + str(temperature/100.0) + " °C")
    print("Humidity: " + str(humidity/100.0) + " %RH")
    print("")

if __name__ == "__main__":
    ipcon = IPConnection() # Create IP connection
    co2 = BrickletCO2V2(UID, ipcon) # Create device object

    ipcon.connect(HOST, PORT) # Connect to brickd
    # Don't use device before ipcon is connected

    # Register all values callback to function cb_all_values
    co2.register_callback(co2.CALLBACK_ALL_VALUES, cb_all_values)

    # Set period for all values callback to 1s (1000ms)
    co2.set_all_values_callback_configuration(1000, False)

    raw_input("Press key to exit\n") # Use input() in Python 3
    ipcon.disconnect()

Compensation

Download (example_compensation.py)

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#!/usr/bin/env python
# -*- coding: utf-8 -*-

# Use ambient air pressure from Air Quality Bricklet to
# for air pressure compensation feature of CO2 Bricklet 2.0.

HOST = "localhost"
PORT = 4223
UID_CO2 = "XYZ1" # Change XYZ1 to the UID of your CO2 Bricklet 2.0
UID_AQ  = "XYZ2" # Change XYZ2 to the UID of your Air Quality Bricklet

from tinkerforge.ip_connection import IPConnection
from tinkerforge.bricklet_co2_v2 import BrickletCO2V2
from tinkerforge.bricklet_air_quality import BrickletAirQuality

import time

if __name__ == "__main__":
    ipcon = IPConnection() # Create IP connection
    co2 = BrickletCO2V2(UID_CO2, ipcon) # Create device object
    aq = BrickletAirQuality(UID_AQ, ipcon) # Create device object

    ipcon.connect(HOST, PORT) # Connect to brickd
    # Don't use device before ipcon is connected

    # Get air pressure in 0.01 hPa
    air_pressure = aq.get_air_pressure()

    # Set air pressure for calibration in hPa
    co2.set_air_pressure(air_pressure // 100)

    # Get current all values
    while True:
        co2_concentration, temperature, humidity = co2.get_all_values()

        print("CO2 Concentration: " + str(co2_concentration) + " ppm")
        print("Temperature: " + str(temperature/100.0) + " °C")
        print("Humidity: " + str(humidity/100.0) + " %RH")
        print("")

        time.sleep(1)

API

Generally, every function of the Python bindings can throw an tinkerforge.ip_connection.Error exception that has a value and a description property. value can have different values:

  • Error.TIMEOUT = -1
  • Error.NOT_ADDED = -6 (unused since Python bindings version 2.0.0)
  • Error.ALREADY_CONNECTED = -7
  • Error.NOT_CONNECTED = -8
  • Error.INVALID_PARAMETER = -9
  • Error.NOT_SUPPORTED = -10
  • Error.UNKNOWN_ERROR_CODE = -11
  • Error.STREAM_OUT_OF_SYNC = -12
  • Error.INVALID_UID = -13
  • Error.NON_ASCII_CHAR_IN_SECRET = -14

All functions listed below are thread-safe.

Basic Functions

BrickletCO2V2(uid, ipcon)
Parameters:
  • uid – Type: str
  • ipcon – Type: IPConnection
Returns:
  • co2_v2 – Type: BrickletCO2V2

Creates an object with the unique device ID uid:

co2_v2 = BrickletCO2V2("YOUR_DEVICE_UID", ipcon)

This object can then be used after the IP Connection is connected (see examples above).

BrickletCO2V2.get_all_values()
Return Object:
  • co2_concentration – Type: int, Unit: 1 ppm, Range: [0 to 40000]
  • temperature – Type: int, Unit: 1/100 °C, Range: [-4000 to 12000]
  • humidity – Type: int, Unit: 1/100 %, Range: [0 to 10000]

Returns all values measured by the CO2 Bricklet 2.0.

If you want to get the values periodically, it is recommended to use the CALLBACK_ALL_VALUES callback. You can set the callback configuration with set_all_values_callback_configuration().

Note

The sensor is able to messure up to 120 °C. However it is only specified up to 70 °C. Exposing the Bricklet to higher temperatures might result in permanent damage.

BrickletCO2V2.set_air_pressure(air_pressure)
Parameters:
  • air_pressure – Type: int, Unit: 1 hPa, Range: [0, 700 to 1200], Default: 0
Returns:
  • None

The CO2 concentration (among other things) depends on the ambient air pressure.

To increase the accuracy of the CO2 Bricklet 2.0 you can set the current air pressure. You use the Barometer Bricklet 2.0 or the Air Quality Bricklet to get the current air pressure.

By default air pressure compensation is disabled. Once you set a value it will be used for compensation. You can turn the compensation off again by setting the value to 0.

It is sufficient to update the value every few minutes.

BrickletCO2V2.get_air_pressure()
Returns:
  • air_pressure – Type: int, Unit: 1 hPa, Range: [0, 700 to 1200], Default: 0

Returns the ambient air pressure as set by set_air_pressure().

BrickletCO2V2.set_temperature_offset(offset)
Parameters:
  • offset – Type: int, Unit: 1/100 °C, Range: [0 to 216 - 1]
Returns:
  • None

Sets a temperature offset. A offset of 10 will decrease the measured temperature by 0.1 °C.

If you install this Bricklet into an enclosure and you want to measure the ambient temperature, you may have to decrease the measured temperature by some value to compensate for the error because of the heating inside of the enclosure.

We recommend that you leave the parts in the enclosure running for at least 24 hours such that a temperature equilibrium can be reached. After that you can measure the temperature directly outside of enclosure and set the difference as offset.

This temperature offset is used to calculate the relative humidity and CO2 concentration. In case the Bricklet is installed in an enclosure, we recommend to measure and set the temperature offset to improve the accuracy of the measurements.

It is sufficient to set the temperature offset once. The offset is saved in non-volatile memory and is applied again after a power loss.

BrickletCO2V2.get_temperature_offset()
Returns:
  • offset – Type: int, Unit: 1/100 °C, Range: [0 to 216 - 1]

Returns the temperature offset as set by set_temperature_offset().

BrickletCO2V2.get_co2_concentration()
Returns:
  • co2_concentration – Type: int, Unit: 1 ppm, Range: [0 to 40000]

Returns CO2 concentration.

If you want to get the value periodically, it is recommended to use the CALLBACK_CO2_CONCENTRATION callback. You can set the callback configuration with set_co2_concentration_callback_configuration().

BrickletCO2V2.get_temperature()
Returns:
  • temperature – Type: int, Unit: 1/100 °C, Range: [-4000 to 12000]

Returns temperature.

Note

The sensor is able to messure up to 120 °C. However it is only specified up to 70 °C. Exposing the Bricklet to higher temperatures might result in permanent damage.

If you want to get the value periodically, it is recommended to use the CALLBACK_TEMPERATURE callback. You can set the callback configuration with set_temperature_callback_configuration().

BrickletCO2V2.get_humidity()
Returns:
  • humidity – Type: int, Unit: 1/100 %, Range: [0 to 10000]

Returns relative humidity.

If you want to get the value periodically, it is recommended to use the CALLBACK_HUMIDITY callback. You can set the callback configuration with set_humidity_callback_configuration().

Advanced Functions

BrickletCO2V2.get_spitfp_error_count()
Return Object:
  • error_count_ack_checksum – Type: int, Range: [0 to 232 - 1]
  • error_count_message_checksum – Type: int, Range: [0 to 232 - 1]
  • error_count_frame – Type: int, Range: [0 to 232 - 1]
  • error_count_overflow – Type: int, 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.

BrickletCO2V2.set_bootloader_mode(mode)
Parameters:
  • mode – Type: int, Range: See constants
Returns:
  • status – Type: int, Range: See constants

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 constants are available for this function:

For mode:

  • BrickletCO2V2.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletCO2V2.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletCO2V2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletCO2V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletCO2V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

For status:

  • BrickletCO2V2.BOOTLOADER_STATUS_OK = 0
  • BrickletCO2V2.BOOTLOADER_STATUS_INVALID_MODE = 1
  • BrickletCO2V2.BOOTLOADER_STATUS_NO_CHANGE = 2
  • BrickletCO2V2.BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BrickletCO2V2.BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BrickletCO2V2.BOOTLOADER_STATUS_CRC_MISMATCH = 5
BrickletCO2V2.get_bootloader_mode()
Returns:
  • mode – Type: int, Range: See constants

Returns the current bootloader mode, see set_bootloader_mode().

The following constants are available for this function:

For mode:

  • BrickletCO2V2.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletCO2V2.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletCO2V2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletCO2V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletCO2V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
BrickletCO2V2.set_write_firmware_pointer(pointer)
Parameters:
  • pointer – Type: int, Unit: 1 B, Range: [0 to 232 - 1]
Returns:
  • None

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.

BrickletCO2V2.write_firmware(data)
Parameters:
  • data – Type: [int, ...], Length: 64, Range: [0 to 255]
Returns:
  • status – Type: int, 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.

BrickletCO2V2.set_status_led_config(config)
Parameters:
  • config – Type: int, Range: See constants, Default: 3
Returns:
  • None

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 constants are available for this function:

For config:

  • BrickletCO2V2.STATUS_LED_CONFIG_OFF = 0
  • BrickletCO2V2.STATUS_LED_CONFIG_ON = 1
  • BrickletCO2V2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletCO2V2.STATUS_LED_CONFIG_SHOW_STATUS = 3
BrickletCO2V2.get_status_led_config()
Returns:
  • config – Type: int, Range: See constants, Default: 3

Returns the configuration as set by set_status_led_config()

The following constants are available for this function:

For config:

  • BrickletCO2V2.STATUS_LED_CONFIG_OFF = 0
  • BrickletCO2V2.STATUS_LED_CONFIG_ON = 1
  • BrickletCO2V2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletCO2V2.STATUS_LED_CONFIG_SHOW_STATUS = 3
BrickletCO2V2.get_chip_temperature()
Returns:
  • temperature – Type: int, 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.

BrickletCO2V2.reset()
Returns:
  • None

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!

BrickletCO2V2.write_uid(uid)
Parameters:
  • uid – Type: int, Range: [0 to 232 - 1]
Returns:
  • None

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.

BrickletCO2V2.read_uid()
Returns:
  • uid – Type: int, Range: [0 to 232 - 1]

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

BrickletCO2V2.get_identity()
Return Object:
  • uid – Type: str, Length: up to 8
  • connected_uid – Type: str, Length: up to 8
  • position – Type: chr, Range: ["a" to "h", "i", "z"]
  • hardware_version – Type: [int, ...], Length: 3
    • 0: major – Type: int, Range: [0 to 255]
    • 1: minor – Type: int, Range: [0 to 255]
    • 2: revision – Type: int, Range: [0 to 255]
  • firmware_version – Type: [int, ...], Length: 3
    • 0: major – Type: int, Range: [0 to 255]
    • 1: minor – Type: int, Range: [0 to 255]
    • 2: revision – Type: int, Range: [0 to 255]
  • device_identifier – Type: int, 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). The Raspberry Pi HAT (Zero) Brick is always at position 'i' and the Bricklet connected to an Isolator Bricklet is always as position 'z'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

Callback Configuration Functions

BrickletCO2V2.register_callback(callback_id, function)
Parameters:
  • callback_id – Type: int
  • function – Type: callable
Returns:
  • None

Registers the given function with the given callback_id.

The available callback IDs with corresponding function signatures are listed below.

BrickletCO2V2.set_all_values_callback_configuration(period, value_has_to_change)
Parameters:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • value_has_to_change – Type: bool, Default: False
Returns:
  • None

The period is the period with which the CALLBACK_ALL_VALUES callback is triggered periodically. A value of 0 turns the callback off.

If the value has to change-parameter is set to true, the callback is only triggered after at least one of the values has changed. If the values didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

BrickletCO2V2.get_all_values_callback_configuration()
Return Object:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • value_has_to_change – Type: bool, Default: False

Returns the callback configuration as set by set_all_values_callback_configuration().

BrickletCO2V2.set_co2_concentration_callback_configuration(period, value_has_to_change, option, min, max)
Parameters:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • value_has_to_change – Type: bool, Default: False
  • option – Type: chr, Range: See constants, Default: "x"
  • min – Type: int, Unit: 1 ppm, Range: [0 to 216 - 1], Default: 0
  • max – Type: int, Unit: 1 ppm, Range: [0 to 216 - 1], Default: 0
Returns:
  • None

The period is the period with which the CALLBACK_CO2_CONCENTRATION callback is triggered periodically. A value of 0 turns the callback off.

If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the CALLBACK_CO2_CONCENTRATION callback.

The following options are possible:

Option Description
'x' Threshold is turned off
'o' Threshold is triggered when the value is outside the min and max values
'i' Threshold is triggered when the value is inside or equal to the min and max values
'<' Threshold is triggered when the value is smaller than the min value (max is ignored)
'>' Threshold is triggered when the value is greater than the min value (max is ignored)

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The following constants are available for this function:

For option:

  • BrickletCO2V2.THRESHOLD_OPTION_OFF = "x"
  • BrickletCO2V2.THRESHOLD_OPTION_OUTSIDE = "o"
  • BrickletCO2V2.THRESHOLD_OPTION_INSIDE = "i"
  • BrickletCO2V2.THRESHOLD_OPTION_SMALLER = "<"
  • BrickletCO2V2.THRESHOLD_OPTION_GREATER = ">"
BrickletCO2V2.get_co2_concentration_callback_configuration()
Return Object:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • value_has_to_change – Type: bool, Default: False
  • option – Type: chr, Range: See constants, Default: "x"
  • min – Type: int, Unit: 1 ppm, Range: [0 to 216 - 1], Default: 0
  • max – Type: int, Unit: 1 ppm, Range: [0 to 216 - 1], Default: 0

Returns the callback configuration as set by set_co2_concentration_callback_configuration().

The following constants are available for this function:

For option:

  • BrickletCO2V2.THRESHOLD_OPTION_OFF = "x"
  • BrickletCO2V2.THRESHOLD_OPTION_OUTSIDE = "o"
  • BrickletCO2V2.THRESHOLD_OPTION_INSIDE = "i"
  • BrickletCO2V2.THRESHOLD_OPTION_SMALLER = "<"
  • BrickletCO2V2.THRESHOLD_OPTION_GREATER = ">"
BrickletCO2V2.set_temperature_callback_configuration(period, value_has_to_change, option, min, max)
Parameters:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • value_has_to_change – Type: bool, Default: False
  • option – Type: chr, Range: See constants, Default: "x"
  • min – Type: int, Unit: 1/100 °C, Range: [-215 to 215 - 1], Default: 0
  • max – Type: int, Unit: 1/100 °C, Range: [-215 to 215 - 1], Default: 0
Returns:
  • None

The period is the period with which the CALLBACK_TEMPERATURE callback is triggered periodically. A value of 0 turns the callback off.

If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the CALLBACK_TEMPERATURE callback.

The following options are possible:

Option Description
'x' Threshold is turned off
'o' Threshold is triggered when the value is outside the min and max values
'i' Threshold is triggered when the value is inside or equal to the min and max values
'<' Threshold is triggered when the value is smaller than the min value (max is ignored)
'>' Threshold is triggered when the value is greater than the min value (max is ignored)

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The following constants are available for this function:

For option:

  • BrickletCO2V2.THRESHOLD_OPTION_OFF = "x"
  • BrickletCO2V2.THRESHOLD_OPTION_OUTSIDE = "o"
  • BrickletCO2V2.THRESHOLD_OPTION_INSIDE = "i"
  • BrickletCO2V2.THRESHOLD_OPTION_SMALLER = "<"
  • BrickletCO2V2.THRESHOLD_OPTION_GREATER = ">"
BrickletCO2V2.get_temperature_callback_configuration()
Return Object:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • value_has_to_change – Type: bool, Default: False
  • option – Type: chr, Range: See constants, Default: "x"
  • min – Type: int, Unit: 1/100 °C, Range: [-215 to 215 - 1], Default: 0
  • max – Type: int, Unit: 1/100 °C, Range: [-215 to 215 - 1], Default: 0

Returns the callback configuration as set by set_temperature_callback_configuration().

The following constants are available for this function:

For option:

  • BrickletCO2V2.THRESHOLD_OPTION_OFF = "x"
  • BrickletCO2V2.THRESHOLD_OPTION_OUTSIDE = "o"
  • BrickletCO2V2.THRESHOLD_OPTION_INSIDE = "i"
  • BrickletCO2V2.THRESHOLD_OPTION_SMALLER = "<"
  • BrickletCO2V2.THRESHOLD_OPTION_GREATER = ">"
BrickletCO2V2.set_humidity_callback_configuration(period, value_has_to_change, option, min, max)
Parameters:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • value_has_to_change – Type: bool, Default: False
  • option – Type: chr, Range: See constants, Default: "x"
  • min – Type: int, Unit: 1/100 %, Range: [0 to 216 - 1], Default: 0
  • max – Type: int, Unit: 1/100 %, Range: [0 to 216 - 1], Default: 0
Returns:
  • None

The period is the period with which the CALLBACK_HUMIDITY callback is triggered periodically. A value of 0 turns the callback off.

If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the CALLBACK_HUMIDITY callback.

The following options are possible:

Option Description
'x' Threshold is turned off
'o' Threshold is triggered when the value is outside the min and max values
'i' Threshold is triggered when the value is inside or equal to the min and max values
'<' Threshold is triggered when the value is smaller than the min value (max is ignored)
'>' Threshold is triggered when the value is greater than the min value (max is ignored)

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The following constants are available for this function:

For option:

  • BrickletCO2V2.THRESHOLD_OPTION_OFF = "x"
  • BrickletCO2V2.THRESHOLD_OPTION_OUTSIDE = "o"
  • BrickletCO2V2.THRESHOLD_OPTION_INSIDE = "i"
  • BrickletCO2V2.THRESHOLD_OPTION_SMALLER = "<"
  • BrickletCO2V2.THRESHOLD_OPTION_GREATER = ">"
BrickletCO2V2.get_humidity_callback_configuration()
Return Object:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • value_has_to_change – Type: bool, Default: False
  • option – Type: chr, Range: See constants, Default: "x"
  • min – Type: int, Unit: 1/100 %, Range: [0 to 216 - 1], Default: 0
  • max – Type: int, Unit: 1/100 %, Range: [0 to 216 - 1], Default: 0

Returns the callback configuration as set by set_humidity_callback_configuration().

The following constants are available for this function:

For option:

  • BrickletCO2V2.THRESHOLD_OPTION_OFF = "x"
  • BrickletCO2V2.THRESHOLD_OPTION_OUTSIDE = "o"
  • BrickletCO2V2.THRESHOLD_OPTION_INSIDE = "i"
  • BrickletCO2V2.THRESHOLD_OPTION_SMALLER = "<"
  • BrickletCO2V2.THRESHOLD_OPTION_GREATER = ">"

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the register_callback() function of the device object. The first parameter is the callback ID and the second parameter the callback function:

def my_callback(param):
    print(param)

co2_v2.register_callback(BrickletCO2V2.CALLBACK_EXAMPLE, my_callback)

The available constants with inherent number and type of parameters are described below.

Note

Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.

BrickletCO2V2.CALLBACK_ALL_VALUES
Callback Parameters:
  • co2_concentration – Type: int, Unit: 1 ppm, Range: [0 to 40000]
  • temperature – Type: int, Unit: 1/100 °C, Range: [-4000 to 12000]
  • humidity – Type: int, Unit: 1/100 %, Range: [0 to 10000]

This callback is triggered periodically according to the configuration set by set_all_values_callback_configuration().

The parameters are the same as get_all_values().

Note

The sensor is able to messure up to 120 °C. However it is only specified up to 70 °C. Exposing the Bricklet to higher temperatures might result in permanent damage.

BrickletCO2V2.CALLBACK_CO2_CONCENTRATION
Callback Parameters:
  • co2_concentration – Type: int, Unit: 1 ppm, Range: [0 to 40000]

This callback is triggered periodically according to the configuration set by set_co2_concentration_callback_configuration().

The parameter is the same as get_co2_concentration().

BrickletCO2V2.CALLBACK_TEMPERATURE
Callback Parameters:
  • temperature – Type: int, Unit: 1/100 °C, Range: [-4000 to 12000]

This callback is triggered periodically according to the configuration set by set_temperature_callback_configuration().

The parameter is the same as get_temperature().

BrickletCO2V2.CALLBACK_HUMIDITY
Callback Parameters:
  • humidity – Type: int, Unit: 1/100 %, Range: [0 to 10000]

This callback is triggered periodically according to the configuration set by set_humidity_callback_configuration().

The parameter is the same as get_humidity().

Virtual Functions

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.

BrickletCO2V2.get_api_version()
Return Object:
  • api_version – Type: [int, ...], Length: 3
    • 0: major – Type: int, Range: [0 to 255]
    • 1: minor – Type: int, Range: [0 to 255]
    • 2: revision – Type: int, Range: [0 to 255]

Returns the version of the API definition implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

BrickletCO2V2.get_response_expected(function_id)
Parameters:
  • function_id – Type: int, Range: See constants
Returns:
  • response_expected – Type: bool

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by set_response_expected(). For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For function_id:

  • BrickletCO2V2.FUNCTION_SET_AIR_PRESSURE = 2
  • BrickletCO2V2.FUNCTION_SET_TEMPERATURE_OFFSET = 4
  • BrickletCO2V2.FUNCTION_SET_ALL_VALUES_CALLBACK_CONFIGURATION = 6
  • BrickletCO2V2.FUNCTION_SET_CO2_CONCENTRATION_CALLBACK_CONFIGURATION = 10
  • BrickletCO2V2.FUNCTION_SET_TEMPERATURE_CALLBACK_CONFIGURATION = 14
  • BrickletCO2V2.FUNCTION_SET_HUMIDITY_CALLBACK_CONFIGURATION = 18
  • BrickletCO2V2.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletCO2V2.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletCO2V2.FUNCTION_RESET = 243
  • BrickletCO2V2.FUNCTION_WRITE_UID = 248
BrickletCO2V2.set_response_expected(function_id, response_expected)
Parameters:
  • function_id – Type: int, Range: See constants
  • response_expected – Type: bool
Returns:
  • None

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For function_id:

  • BrickletCO2V2.FUNCTION_SET_AIR_PRESSURE = 2
  • BrickletCO2V2.FUNCTION_SET_TEMPERATURE_OFFSET = 4
  • BrickletCO2V2.FUNCTION_SET_ALL_VALUES_CALLBACK_CONFIGURATION = 6
  • BrickletCO2V2.FUNCTION_SET_CO2_CONCENTRATION_CALLBACK_CONFIGURATION = 10
  • BrickletCO2V2.FUNCTION_SET_TEMPERATURE_CALLBACK_CONFIGURATION = 14
  • BrickletCO2V2.FUNCTION_SET_HUMIDITY_CALLBACK_CONFIGURATION = 18
  • BrickletCO2V2.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletCO2V2.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletCO2V2.FUNCTION_RESET = 243
  • BrickletCO2V2.FUNCTION_WRITE_UID = 248
BrickletCO2V2.set_response_expected_all(response_expected)
Parameters:
  • response_expected – Type: bool
Returns:
  • None

Changes the response expected flag for all setter and callback configuration functions of this device at once.

Constants

BrickletCO2V2.DEVICE_IDENTIFIER

This constant is used to identify a CO2 Bricklet 2.0.

The get_identity() function and the IPConnection.CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.

BrickletCO2V2.DEVICE_DISPLAY_NAME

This constant represents the human readable name of a CO2 Bricklet 2.0.