Perl - Temperature IR Bricklet

This is the description of the Perl API bindings for the Temperature IR Bricklet. General information and technical specifications for the Temperature IR Bricklet 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::BrickletTemperatureIR;

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

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

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

# Get current ambient temperature
my $ambient_temperature = $tir->get_ambient_temperature();
print "Ambient Temperature: " . $ambient_temperature/10.0 . " °C\n";

# Get current object temperature
my $object_temperature = $tir->get_object_temperature();
print "Object Temperature: " . $object_temperature/10.0 . " °C\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::BrickletTemperatureIR;

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

# Callback subroutine for object temperature callback
sub cb_object_temperature
{
    my ($temperature) = @_;

    print "Object Temperature: " . $temperature/10.0 . " °C\n";
}

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

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

# Register object temperature callback to subroutine cb_object_temperature
$tir->register_callback($tir->CALLBACK_OBJECT_TEMPERATURE, 'cb_object_temperature');

# Set period for object temperature callback to 1s (1000ms)
# Note: The object temperature callback is only called every second
#       if the object temperature has changed since the last call!
$tir->set_object_temperature_callback_period(1000);

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

Water Boiling

Download (example_water_boiling.pl)

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#!/usr/bin/perl

use strict;
use Tinkerforge::IPConnection;
use Tinkerforge::BrickletTemperatureIR;

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

# Callback subroutine for object temperature reached callback
sub cb_object_temperature_reached
{
    my ($temperature) = @_;

    print "Object Temperature: " . $temperature/10.0 . " °C\n";
    print "The water is boiling!\n";
}

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

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

# Set emissivity to 0.98 (emissivity of water, 65535 * 0.98 = 64224.299)
$tir->set_emissivity(64224);

# Get threshold callbacks with a debounce time of 10 seconds (10000ms)
$tir->set_debounce_period(10000);

# Register object temperature reached callback to subroutine cb_object_temperature_reached
$tir->register_callback($tir->CALLBACK_OBJECT_TEMPERATURE_REACHED,
                        'cb_object_temperature_reached');

# Configure threshold for object temperature "greater than 100 °C"
$tir->set_object_temperature_callback_threshold('>', 100*10, 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

All methods listed below are thread-safe.

Basic Functions

BrickletTemperatureIR->new($uid, $ipcon)
Parameters:
  • $uid -- string
  • $ipcon -- IPConnection
Return type:

BrickletTemperatureIR

Creates an object with the unique device ID $uid:

$temperature_ir = BrickletTemperatureIR->new("YOUR_DEVICE_UID", $ipcon);

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

BrickletTemperatureIR->get_ambient_temperature()
Return type:int

Returns the ambient temperature of the sensor. The value has a range of -400 to 1250 and is given in °C/10, e.g. a value of 423 means that an ambient temperature of 42.3 °C is measured.

If you want to get the ambient temperature periodically, it is recommended to use the CALLBACK_AMBIENT_TEMPERATURE callback and set the period with set_ambient_temperature_callback_period().

BrickletTemperatureIR->get_object_temperature()
Return type:int

Returns the object temperature of the sensor, i.e. the temperature of the surface of the object the sensor is aimed at. The value has a range of -700 to 3800 and is given in °C/10, e.g. a value of 3001 means that a temperature of 300.1 °C is measured on the surface of the object.

The temperature of different materials is dependent on their emissivity. The emissivity of the material can be set with set_emissivity().

If you want to get the object temperature periodically, it is recommended to use the CALLBACK_OBJECT_TEMPERATURE callback and set the period with set_object_temperature_callback_period().

Advanced Functions

BrickletTemperatureIR->set_emissivity($emissivity)
Parameters:$emissivity -- int
Return type:undef

Sets the emissivity that is used to calculate the surface temperature as returned by get_object_temperature().

The emissivity is usually given as a value between 0.0 and 1.0. A list of emissivities of different materials can be found here.

The parameter of set_emissivity() has to be given with a factor of 65535 (16-bit). For example: An emissivity of 0.1 can be set with the value 6553, an emissivity of 0.5 with the value 32767 and so on.

Note

If you need a precise measurement for the object temperature, it is absolutely crucial that you also provide a precise emissivity.

The default emissivity is 1.0 (value of 65535) and the minimum emissivity the sensor can handle is 0.1 (value of 6553).

The emissivity is stored in non-volatile memory and will still be used after a restart or power cycle of the Bricklet.

BrickletTemperatureIR->get_emissivity()
Return type:int

Returns the emissivity as set by set_emissivity().

BrickletTemperatureIR->get_api_version()
Return type:[int, int, int]

Returns the version of the API definition (major, minor, revision) 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.

BrickletTemperatureIR->get_response_expected($function_id)
Parameters:$function_id -- int
Return 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.

See set_response_expected() for the list of function ID constants available for this function.

BrickletTemperatureIR->set_response_expected($function_id, $response_expected)
Parameters:
  • $function_id -- int
  • $response_expected -- bool
Return type:

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 function ID constants are available for this function:

  • BrickletTemperatureIR->FUNCTION_SET_EMISSIVITY = 3
  • BrickletTemperatureIR->FUNCTION_SET_AMBIENT_TEMPERATURE_CALLBACK_PERIOD = 5
  • BrickletTemperatureIR->FUNCTION_SET_OBJECT_TEMPERATURE_CALLBACK_PERIOD = 7
  • BrickletTemperatureIR->FUNCTION_SET_AMBIENT_TEMPERATURE_CALLBACK_THRESHOLD = 9
  • BrickletTemperatureIR->FUNCTION_SET_OBJECT_TEMPERATURE_CALLBACK_THRESHOLD = 11
  • BrickletTemperatureIR->FUNCTION_SET_DEBOUNCE_PERIOD = 13
BrickletTemperatureIR->set_response_expected_all($response_expected)
Parameters:$response_expected -- bool
Return type:undef

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

BrickletTemperatureIR->get_identity()
Return type:[string, string, char, [int, int, int], [int, int, int], int]

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' or 'd'.

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

The returned array contains the elements uid, connected_uid, position, hardware_version, firmware_version and device_identifier.

Callback Configuration Functions

BrickletTemperatureIR->register_callback($id, $callback)
Parameters:
  • $id -- int
  • $callback -- string
Return type:

undef

Registers the given $function name with the given $callback_id.

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

BrickletTemperatureIR->set_ambient_temperature_callback_period($period)
Parameters:$period -- int
Return type:undef

Sets the period in ms with which the CALLBACK_AMBIENT_TEMPERATURE callback is triggered periodically. A value of 0 turns the callback off.

The CALLBACK_AMBIENT_TEMPERATURE callback is only triggered if the temperature has changed since the last triggering.

The default value is 0.

BrickletTemperatureIR->get_ambient_temperature_callback_period()
Return type:int

Returns the period as set by set_ambient_temperature_callback_period().

BrickletTemperatureIR->set_object_temperature_callback_period($period)
Parameters:$period -- int
Return type:undef

Sets the period in ms with which the CALLBACK_OBJECT_TEMPERATURE callback is triggered periodically. A value of 0 turns the callback off.

The CALLBACK_OBJECT_TEMPERATURE callback is only triggered if the temperature has changed since the last triggering.

The default value is 0.

BrickletTemperatureIR->get_object_temperature_callback_period()
Return type:int

Returns the period as set by set_object_temperature_callback_period().

BrickletTemperatureIR->set_ambient_temperature_callback_threshold($option, $min, $max)
Parameters:
  • $option -- char
  • $min -- int
  • $max -- int
Return type:

undef

Sets the thresholds for the CALLBACK_AMBIENT_TEMPERATURE_REACHED callback.

The following options are possible:

Option Description
'x' Callback is turned off
'o' Callback is triggered when the ambient temperature is outside the min and max values
'i' Callback is triggered when the ambient temperature is inside the min and max values
'<' Callback is triggered when the ambient temperature is smaller than the min value (max is ignored)
'>' Callback is triggered when the ambient temperature is greater than the min value (max is ignored)

The default value is ('x', 0, 0).

The following constants are available for this function:

  • BrickletTemperatureIR->THRESHOLD_OPTION_OFF = 'x'
  • BrickletTemperatureIR->THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletTemperatureIR->THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletTemperatureIR->THRESHOLD_OPTION_SMALLER = '<'
  • BrickletTemperatureIR->THRESHOLD_OPTION_GREATER = '>'
BrickletTemperatureIR->get_ambient_temperature_callback_threshold()
Return type:[char, int, int]

Returns the threshold as set by set_ambient_temperature_callback_threshold().

The following constants are available for this function:

  • BrickletTemperatureIR->THRESHOLD_OPTION_OFF = 'x'
  • BrickletTemperatureIR->THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletTemperatureIR->THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletTemperatureIR->THRESHOLD_OPTION_SMALLER = '<'
  • BrickletTemperatureIR->THRESHOLD_OPTION_GREATER = '>'

The returned array contains the elements option, min and max.

BrickletTemperatureIR->set_object_temperature_callback_threshold($option, $min, $max)
Parameters:
  • $option -- char
  • $min -- int
  • $max -- int
Return type:

undef

Sets the thresholds for the CALLBACK_OBJECT_TEMPERATURE_REACHED callback.

The following options are possible:

Option Description
'x' Callback is turned off
'o' Callback is triggered when the object temperature is outside the min and max values
'i' Callback is triggered when the object temperature is inside the min and max values
'<' Callback is triggered when the object temperature is smaller than the min value (max is ignored)
'>' Callback is triggered when the object temperature is greater than the min value (max is ignored)

The default value is ('x', 0, 0).

The following constants are available for this function:

  • BrickletTemperatureIR->THRESHOLD_OPTION_OFF = 'x'
  • BrickletTemperatureIR->THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletTemperatureIR->THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletTemperatureIR->THRESHOLD_OPTION_SMALLER = '<'
  • BrickletTemperatureIR->THRESHOLD_OPTION_GREATER = '>'
BrickletTemperatureIR->get_object_temperature_callback_threshold()
Return type:[char, int, int]

Returns the threshold as set by set_object_temperature_callback_threshold().

The following constants are available for this function:

  • BrickletTemperatureIR->THRESHOLD_OPTION_OFF = 'x'
  • BrickletTemperatureIR->THRESHOLD_OPTION_OUTSIDE = 'o'
  • BrickletTemperatureIR->THRESHOLD_OPTION_INSIDE = 'i'
  • BrickletTemperatureIR->THRESHOLD_OPTION_SMALLER = '<'
  • BrickletTemperatureIR->THRESHOLD_OPTION_GREATER = '>'

The returned array contains the elements option, min and max.

BrickletTemperatureIR->set_debounce_period($debounce)
Parameters:$debounce -- int
Return type:undef

Sets the period in ms with which the threshold callbacks

are triggered, if the thresholds

keep being reached.

The default value is 100.

BrickletTemperatureIR->get_debounce_period()
Return type:int

Returns the debounce period as set by set_debounce_period().

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]";
}

$temperature_ir->register_callback(BrickletTemperatureIR->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.

BrickletTemperatureIR->CALLBACK_AMBIENT_TEMPERATURE
Parameters:$temperature -- int

This callback is triggered periodically with the period that is set by set_ambient_temperature_callback_period(). The parameter is the ambient temperature of the sensor.

The CALLBACK_AMBIENT_TEMPERATURE callback is only triggered if the ambient temperature has changed since the last triggering.

BrickletTemperatureIR->CALLBACK_OBJECT_TEMPERATURE
Parameters:$temperature -- int

This callback is triggered periodically with the period that is set by set_object_temperature_callback_period(). The parameter is the object temperature of the sensor.

The CALLBACK_OBJECT_TEMPERATURE callback is only triggered if the object temperature has changed since the last triggering.

BrickletTemperatureIR->CALLBACK_AMBIENT_TEMPERATURE_REACHED
Parameters:$temperature -- int

This callback is triggered when the threshold as set by set_ambient_temperature_callback_threshold() is reached. The parameter is the ambient temperature of the sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by set_debounce_period().

BrickletTemperatureIR->CALLBACK_OBJECT_TEMPERATURE_REACHED
Parameters:$temperature -- int

This callback is triggered when the threshold as set by set_object_temperature_callback_threshold() is reached. The parameter is the object temperature of the sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by set_debounce_period().

Constants

BrickletTemperatureIR->DEVICE_IDENTIFIER

This constant is used to identify a Temperature IR Bricklet.

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.

BrickletTemperatureIR->DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Temperature IR Bricklet.