Python - Temperature IR Bricklet

This is the description of the Python 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 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 = "abcde" # Change to your UID

from tinkerforge.ip_connection import IPConnection
from tinkerforge.bricklet_temperature_ir import TemperatureIR

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

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

    # Get current object and ambient temperatures (unit is °C/10)
    obj = tir.get_object_temperature()/10.0
    amb = tir.get_ambient_temperature()/10.0

    print('Object Temperature: ' + str(obj) + ' °C')
    print('Ambient Temperature: ' + str(amb) + ' °C')

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

Water Boiling

Download (example_water_boiling.py)

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

HOST = "localhost"
PORT = 4223
UID = "abcde" # Change to your UID

from tinkerforge.ip_connection import IPConnection
from tinkerforge.bricklet_temperature_ir import TemperatureIR

# Callback for object temperature greater than 100 °C
# (parameter has unit °C/10)
def cb_reached(temperature):
    print('The surface has a temperature of ' + str(temperature/10.0) + ' °C.')
    print('The water is boiling!')

if __name__ == "__main__":
    ipcon = IPConnection() # Create IP connection
    tir = TemperatureIR(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)
    tir.set_emissivity(int(0xFFFF*0.98))

    # Get threshold callbacks with a debounce time of 10 seconds (10000ms)
    tir.set_debounce_period(10000)

    # Register threshold reached callback to function cb_reached
    tir.register_callback(tir.CALLBACK_OBJECT_TEMPERATURE_REACHED, cb_reached)

    # Configure threshold for "greater than 100 °C" (unit is °C/10)
    tir.set_object_temperature_callback_threshold('>', 100*10, 0)

    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 = "abcde" # Change to your UID

from tinkerforge.ip_connection import IPConnection
from tinkerforge.bricklet_temperature_ir import TemperatureIR

# Callback functions for object/ambient temperature callbacks 
# (parameters have unit °C/10)
def cb_object(temperature):
    print('Object Temperature: ' + str(temperature/10.0) + ' °C')

def cb_ambient(temperature):
    print('Ambient Temperature: ' + str(temperature/10.0) + ' °C')

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

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

    # Set Period for temperature callbacks to 1s (1000ms)
    # Note: The callbacks are only called every second if the 
    #       value has changed since the last call!
    tir.set_object_temperature_callback_period(1000)
    tir.set_ambient_temperature_callback_period(1000)

    # Register object temperature callback to function cb_object
    tir.register_callback(tir.CALLBACK_OBJECT_TEMPERATURE, cb_object)
    # Register ambient temperature callback to function cb_ambient
    tir.register_callback(tir.CALLBACK_AMBIENT_TEMPERATURE, cb_ambient)

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

API

Generally, every method 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.ALREADY_CONNECTED = -7
  • Error.NOT_CONNECTED = -8
  • Error.INVALID_PARAMETER = -9
  • Error.NOT_SUPPORTED = -10
  • Error.UNKNOWN_ERROR_CODE = -11

All methods listed below are thread-safe.

Basic Functions

TemperatureIR(uid, ipcon)
Parameters:
  • uid -- string
  • ipcon -- IPConnection

Creates an object with the unique device ID uid:

temperature_ir = TemperatureIR("YOUR_DEVICE_UID", ipcon)

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

TemperatureIR.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 CALLBACK_AMBIENT_TEMPERATURE and set the period with set_ambient_temperature_callback_period().

TemperatureIR.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 CALLBACK_OBJECT_TEMPERATURE and set the period with set_object_temperature_callback_period().

Advanced Functions

TemperatureIR.set_emissivity(emissivity)
Parameters:emissivity -- int
Return type:None

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).

TemperatureIR.get_emissivity()
Return type:int

Returns the emissivity as set by set_emissivity().

TemperatureIR.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.

TemperatureIR.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.

TemperatureIR.set_response_expected(function_id, response_expected)
Parameters:
  • function_id -- int
  • response_expected -- bool
Return type:

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 and callbacks it is always disabled.

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:

  • TemperatureIR.FUNCTION_SET_EMISSIVITY = 3
  • TemperatureIR.FUNCTION_SET_AMBIENT_TEMPERATURE_CALLBACK_PERIOD = 5
  • TemperatureIR.FUNCTION_SET_OBJECT_TEMPERATURE_CALLBACK_PERIOD = 7
  • TemperatureIR.FUNCTION_SET_AMBIENT_TEMPERATURE_CALLBACK_THRESHOLD = 9
  • TemperatureIR.FUNCTION_SET_OBJECT_TEMPERATURE_CALLBACK_THRESHOLD = 11
  • TemperatureIR.FUNCTION_SET_DEBOUNCE_PERIOD = 13
TemperatureIR.set_response_expected_all(response_expected)
Parameters:response_expected -- bool
Return type:None

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

TemperatureIR.get_identity()
Return type:(str, str, chr, [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 namedtuple has the variables uid, connected_uid, position, hardware_version, firmware_version and device_identifier.

Callback Configuration Functions

TemperatureIR.register_callback(id, callback)
Parameters:
  • id -- int
  • callback -- callable
Return type:

None

Registers a callback with ID id to the function callback. The available IDs with corresponding function signatures are listed below.

TemperatureIR.set_ambient_temperature_callback_period(period)
Parameters:period -- int
Return type:None

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

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

The default value is 0.

TemperatureIR.get_ambient_temperature_callback_period()
Return type:int

Returns the period as set by set_ambient_temperature_callback_period().

TemperatureIR.set_object_temperature_callback_period(period)
Parameters:period -- int
Return type:None

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

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

The default value is 0.

TemperatureIR.get_object_temperature_callback_period()
Return type:int

Returns the period as set by set_object_temperature_callback_period().

TemperatureIR.set_ambient_temperature_callback_threshold(option, min, max)
Parameters:
  • option -- chr
  • min -- int
  • max -- int
Return type:

None

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:

  • TemperatureIR.THRESHOLD_OPTION_OFF = 'x'
  • TemperatureIR.THRESHOLD_OPTION_OUTSIDE = 'o'
  • TemperatureIR.THRESHOLD_OPTION_INSIDE = 'i'
  • TemperatureIR.THRESHOLD_OPTION_SMALLER = '<'
  • TemperatureIR.THRESHOLD_OPTION_GREATER = '>'
TemperatureIR.get_ambient_temperature_callback_threshold()
Return type:(chr, int, int)

Returns the threshold as set by set_ambient_temperature_callback_threshold().

The following constants are available for this function:

  • TemperatureIR.THRESHOLD_OPTION_OFF = 'x'
  • TemperatureIR.THRESHOLD_OPTION_OUTSIDE = 'o'
  • TemperatureIR.THRESHOLD_OPTION_INSIDE = 'i'
  • TemperatureIR.THRESHOLD_OPTION_SMALLER = '<'
  • TemperatureIR.THRESHOLD_OPTION_GREATER = '>'

The returned namedtuple has the variables option, min and max.

TemperatureIR.set_object_temperature_callback_threshold(option, min, max)
Parameters:
  • option -- chr
  • min -- int
  • max -- int
Return type:

None

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:

  • TemperatureIR.THRESHOLD_OPTION_OFF = 'x'
  • TemperatureIR.THRESHOLD_OPTION_OUTSIDE = 'o'
  • TemperatureIR.THRESHOLD_OPTION_INSIDE = 'i'
  • TemperatureIR.THRESHOLD_OPTION_SMALLER = '<'
  • TemperatureIR.THRESHOLD_OPTION_GREATER = '>'
TemperatureIR.get_object_temperature_callback_threshold()
Return type:(chr, int, int)

Returns the threshold as set by set_object_temperature_callback_threshold().

The following constants are available for this function:

  • TemperatureIR.THRESHOLD_OPTION_OFF = 'x'
  • TemperatureIR.THRESHOLD_OPTION_OUTSIDE = 'o'
  • TemperatureIR.THRESHOLD_OPTION_INSIDE = 'i'
  • TemperatureIR.THRESHOLD_OPTION_SMALLER = '<'
  • TemperatureIR.THRESHOLD_OPTION_GREATER = '>'

The returned namedtuple has the variables option, min and max.

TemperatureIR.set_debounce_period(debounce)
Parameters:debounce -- int
Return type:None

Sets the period in ms with which the threshold callbacks

are triggered, if the thresholds

keep being reached.

The default value is 100.

TemperatureIR.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:

def my_callback(param):
    print(param)

temperature_ir.register_callback(TemperatureIR.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.

TemperatureIR.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.

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

TemperatureIR.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.

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

TemperatureIR.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().

TemperatureIR.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

TemperatureIR.DEVICE_IDENTIFIER

This constant is used to identify a Temperature IR Bricklet.

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

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