Perl - CO2 Bricklet 2.0

This is the description of the Perl 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 Perl API bindings is part of their general description.

Examples

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

Simple

Download (example_simple.pl)

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#!/usr/bin/perl

use strict;
use Tinkerforge::IPConnection;
use Tinkerforge::BrickletCO2V2;

use constant HOST => 'localhost';
use constant PORT => 4223;
use constant UID => 'XYZ'; # Change XYZ to the UID of your CO2 Bricklet 2.0

my $ipcon = Tinkerforge::IPConnection->new(); # Create IP connection
my $co2 = Tinkerforge::BrickletCO2V2->new(&UID, $ipcon); # Create device object

$ipcon->connect(&HOST, &PORT); # Connect to brickd
# Don't use device before ipcon is connected

# Get current all values
my ($co2_concentration, $temperature, $humidity) = $co2->get_all_values();

print "CO2 Concentration: $co2_concentration ppm\n";
print "Temperature: " . $temperature/100.0 . " °C\n";
print "Humidity: " . $humidity/100.0 . " %RH\n";

print "Press key to exit\n";
<STDIN>;
$ipcon->disconnect();

Callback

Download (example_callback.pl)

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#!/usr/bin/perl

use strict;
use Tinkerforge::IPConnection;
use Tinkerforge::BrickletCO2V2;

use constant HOST => 'localhost';
use constant PORT => 4223;
use constant UID => 'XYZ'; # Change XYZ to the UID of your CO2 Bricklet 2.0

# Callback subroutine for all values callback
sub cb_all_values
{
    my ($co2_concentration, $temperature, $humidity) = @_;

    print "CO2 Concentration: $co2_concentration ppm\n";
    print "Temperature: " . $temperature/100.0 . " °C\n";
    print "Humidity: " . $humidity/100.0 . " %RH\n";
    print "\n";
}

my $ipcon = Tinkerforge::IPConnection->new(); # Create IP connection
my $co2 = Tinkerforge::BrickletCO2V2->new(&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 subroutine 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, 0);

print "Press key to exit\n";
<STDIN>;
$ipcon->disconnect();

API

Generally, every subroutine of the Perl bindings can report an error as Tinkerforge::Error object via croak(). The object has a get_code() and a get_message() subroutine. There are different error code:

  • Error->ALREADY_CONNECTED = 11
  • Error->NOT_CONNECTED = 12
  • Error->CONNECT_FAILED = 13
  • Error->INVALID_FUNCTION_ID = 21
  • Error->TIMEOUT = 31
  • Error->INVALID_PARAMETER = 41
  • Error->FUNCTION_NOT_SUPPORTED = 42
  • Error->UNKNOWN_ERROR = 43
  • Error->STREAM_OUT_OF_SYNC = 51
  • Error->INVALID_UID = 61
  • Error->NON_ASCII_CHAR_IN_SECRET = 71

All functions listed below are thread-safe.

Basic Functions

BrickletCO2V2->new($uid, $ipcon)
Parameters:
  • $uid – Type: string
  • $ipcon – Type: IPConnection
Returns:
  • $co2_v2 – Type: BrickletCO2V2

Creates an object with the unique device ID $uid:

$co2_v2 = BrickletCO2V2->new("YOUR_DEVICE_UID", $ipcon);

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

BrickletCO2V2->get_all_values()
Return Array:
  • 0: $co2_concentration – Type: int, Unit: 1 ppm, Range: [0 to 40000]
  • 1: $temperature – Type: int, Unit: 1/100 °C, Range: [-4000 to 12000]
  • 2: $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:
  • undef

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:
  • undef

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 Array:
  • 0: $error_count_ack_checksum – Type: int, Range: [0 to 232 - 1]
  • 1: $error_count_message_checksum – Type: int, Range: [0 to 232 - 1]
  • 2: $error_count_frame – Type: int, Range: [0 to 232 - 1]
  • 3: $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:
  • undef

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:
  • undef

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:
  • undef

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:
  • undef

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 Array:
  • 0: $uid – Type: string, Length: up to 8
  • 1: $connected_uid – Type: string, Length: up to 8
  • 2: $position – Type: char, Range: ['a' to 'h', 'i', 'z']
  • 3: @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]
  • 4: @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]
  • 5: $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: string
Returns:
  • undef

Registers the given $function name 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: 0
Returns:
  • undef

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 Array:
  • 0: $period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • 1: $value_has_to_change – Type: bool, Default: 0

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: 0
  • $option – Type: char, 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:
  • undef

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 Array:
  • 0: $period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • 1: $value_has_to_change – Type: bool, Default: 0
  • 2: $option – Type: char, Range: See constants, Default: 'x'
  • 3: $min – Type: int, Unit: 1 ppm, Range: [0 to 216 - 1], Default: 0
  • 4: $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: 0
  • $option – Type: char, 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:
  • undef

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 Array:
  • 0: $period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • 1: $value_has_to_change – Type: bool, Default: 0
  • 2: $option – Type: char, Range: See constants, Default: 'x'
  • 3: $min – Type: int, Unit: 1/100 °C, Range: [-215 to 215 - 1], Default: 0
  • 4: $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: 0
  • $option – Type: char, 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:
  • undef

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 Array:
  • 0: $period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
  • 1: $value_has_to_change – Type: bool, Default: 0
  • 2: $option – Type: char, Range: See constants, Default: 'x'
  • 3: $min – Type: int, Unit: 1/100 %, Range: [0 to 216 - 1], Default: 0
  • 4: $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 name:

sub my_callback
{
    print "@_[0]";
}

$co2_v2->register_callback(BrickletCO2V2->CALLBACK_EXAMPLE, 'my_callback')

The callback function will be called from an internal thread of the IP Connection. In contrast to many other programming languages, variables are not automatically shared between threads in Perl. If you want to share a global variable between a callback function and the rest for your program it has to be marked as :shared. See the documentation of the threads::shared Perl module for more details.

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 Array:
  • 0: @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:
  • undef

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:
  • undef

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.