MQTT - Temperature IR Bricklet

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

Examples

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

Simple

Download (example-simple.txt)

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# Change XYZ to the UID of your Temperature IR Bricklet

setup:
    # Get current ambient temperature
    subscribe to tinkerforge/response/temperature_ir_bricklet/XYZ/get_ambient_temperature
    publish '' to tinkerforge/request/temperature_ir_bricklet/XYZ/get_ambient_temperature

    # Get current object temperature
    subscribe to tinkerforge/response/temperature_ir_bricklet/XYZ/get_object_temperature
    publish '' to tinkerforge/request/temperature_ir_bricklet/XYZ/get_object_temperature

Callback

Download (example-callback.txt)

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# Change XYZ to the UID of your Temperature IR Bricklet

setup:
    # Handle incoming object temperature callbacks
    subscribe to tinkerforge/callback/temperature_ir_bricklet/XYZ/object_temperature
    publish '{"register": true}' to tinkerforge/register/temperature_ir_bricklet/XYZ/object_temperature # Register object_temperature callback

    # 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!
    publish '{"period": 1000}' to tinkerforge/request/temperature_ir_bricklet/XYZ/set_object_temperature_callback_period

Water Boiling

Download (example-water-boiling.txt)

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# Change XYZ to the UID of your Temperature IR Bricklet

setup:
    # Set emissivity to 0.98 (emissivity of water, 65535 * 0.98 = 64224.299)
    publish '{"emissivity": 64224}' to tinkerforge/request/temperature_ir_bricklet/XYZ/set_emissivity

    # Get threshold callbacks with a debounce time of 10 seconds (10000ms)
    publish '{"debounce": 10000}' to tinkerforge/request/temperature_ir_bricklet/XYZ/set_debounce_period

    # Handle incoming object temperature reached callbacks
    subscribe to tinkerforge/callback/temperature_ir_bricklet/XYZ/object_temperature_reached
    publish '{"register": true}' to tinkerforge/register/temperature_ir_bricklet/XYZ/object_temperature_reached # Register object_temperature_reached callback

    # Configure threshold for object temperature "greater than 100 °C"
    publish '{"option": "greater", "min": 1000, "max": 0}' to tinkerforge/request/temperature_ir_bricklet/XYZ/set_object_temperature_callback_threshold

API

All published payloads to and from the MQTT bindings are in JSON format.

If an error occures, the bindings publish a JSON object containing the error message as member _ERROR. It is published on the corresponding response topic: .../response/... for .../request/... and .../callback/... for .../register/....

Basic Functions

request/temperature_ir_bricklet/<UID>/get_ambient_temperature
Request:
  • empty payload
Response:
  • temperature – Type: int, Unit: 1/10 °C, Range: [-400 to 1250]

Returns the ambient temperature of the sensor.

If you want to get the ambient temperature periodically, it is recommended to use the register/temperature_ir_bricklet/<UID>/ambient_temperature callback and set the period with request/temperature_ir_bricklet/<UID>/set_ambient_temperature_callback_period.

request/temperature_ir_bricklet/<UID>/get_object_temperature
Request:
  • empty payload
Response:
  • temperature – Type: int, Unit: 1/10 °C, Range: [-700 to 3800]

Returns the object temperature of the sensor, i.e. the temperature of the surface of the object the sensor is aimed at.

The temperature of different materials is dependent on their emissivity. The emissivity of the material can be set with request/temperature_ir_bricklet/<UID>/set_emissivity.

If you want to get the object temperature periodically, it is recommended to use the register/temperature_ir_bricklet/<UID>/object_temperature callback and set the period with request/temperature_ir_bricklet/<UID>/set_object_temperature_callback_period.

Advanced Functions

request/temperature_ir_bricklet/<UID>/set_emissivity
Request:
  • emissivity – Type: int, Unit: 1/65535, Range: [6553 to 216 - 1], Default: 216 - 1
Response:
  • no response

Sets the emissivity that is used to calculate the surface temperature as returned by request/temperature_ir_bricklet/<UID>/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 request/temperature_ir_bricklet/<UID>/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 emissivity is stored in non-volatile memory and will still be used after a restart or power cycle of the Bricklet.

request/temperature_ir_bricklet/<UID>/get_emissivity
Request:
  • empty payload
Response:
  • emissivity – Type: int, Unit: 1/65535, Range: [6553 to 216 - 1], Default: 216 - 1

Returns the emissivity as set by request/temperature_ir_bricklet/<UID>/set_emissivity.

request/temperature_ir_bricklet/<UID>/get_identity
Request:
  • empty payload
Response:
  • uid – Type: string, Length: up to 8
  • connected_uid – Type: string, Length: up to 8
  • position – Type: char, 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]
  • _display_name – Type: string

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. If symbolic output is not disabled, the device identifier is mapped to the corresponding name in the format used in topics.

The display name contains the Temperature IR's name in a human readable form.

Callback Configuration Functions

request/temperature_ir_bricklet/<UID>/set_ambient_temperature_callback_period
Request:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Response:
  • no response

Sets the period with which the register/temperature_ir_bricklet/<UID>/ambient_temperature callback is triggered periodically. A value of 0 turns the callback off.

The register/temperature_ir_bricklet/<UID>/ambient_temperature callback is only triggered if the temperature has changed since the last triggering.

request/temperature_ir_bricklet/<UID>/get_ambient_temperature_callback_period
Request:
  • empty payload
Response:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Returns the period as set by request/temperature_ir_bricklet/<UID>/set_ambient_temperature_callback_period.

request/temperature_ir_bricklet/<UID>/set_object_temperature_callback_period
Request:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Response:
  • no response

Sets the period with which the register/temperature_ir_bricklet/<UID>/object_temperature callback is triggered periodically. A value of 0 turns the callback off.

The register/temperature_ir_bricklet/<UID>/object_temperature callback is only triggered if the temperature has changed since the last triggering.

request/temperature_ir_bricklet/<UID>/get_object_temperature_callback_period
Request:
  • empty payload
Response:
  • period – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Returns the period as set by request/temperature_ir_bricklet/<UID>/set_object_temperature_callback_period.

request/temperature_ir_bricklet/<UID>/set_ambient_temperature_callback_threshold
Request:
  • option – Type: char, Range: See symbols, Default: "x"
  • min – Type: int, Unit: 1/10 °C, Range: [-215 to 215 - 1], Default: 0
  • max – Type: int, Unit: 1/10 °C, Range: [-215 to 215 - 1], Default: 0
Response:
  • no response

Sets the thresholds for the register/temperature_ir_bricklet/<UID>/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 following symbols are available for this function:

For option:

  • "off" = "x"
  • "outside" = "o"
  • "inside" = "i"
  • "smaller" = "<"
  • "greater" = ">"
request/temperature_ir_bricklet/<UID>/get_ambient_temperature_callback_threshold
Request:
  • empty payload
Response:
  • option – Type: char, Range: See symbols, Default: "x"
  • min – Type: int, Unit: 1/10 °C, Range: [-215 to 215 - 1], Default: 0
  • max – Type: int, Unit: 1/10 °C, Range: [-215 to 215 - 1], Default: 0

Returns the threshold as set by request/temperature_ir_bricklet/<UID>/set_ambient_temperature_callback_threshold.

The following symbols are available for this function:

For option:

  • "off" = "x"
  • "outside" = "o"
  • "inside" = "i"
  • "smaller" = "<"
  • "greater" = ">"
request/temperature_ir_bricklet/<UID>/set_object_temperature_callback_threshold
Request:
  • option – Type: char, Range: See symbols, Default: "x"
  • min – Type: int, Unit: 1/10 °C, Range: [-215 to 215 - 1], Default: 0
  • max – Type: int, Unit: 1/10 °C, Range: [-215 to 215 - 1], Default: 0
Response:
  • no response

Sets the thresholds for the register/temperature_ir_bricklet/<UID>/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 following symbols are available for this function:

For option:

  • "off" = "x"
  • "outside" = "o"
  • "inside" = "i"
  • "smaller" = "<"
  • "greater" = ">"
request/temperature_ir_bricklet/<UID>/get_object_temperature_callback_threshold
Request:
  • empty payload
Response:
  • option – Type: char, Range: See symbols, Default: "x"
  • min – Type: int, Unit: 1/10 °C, Range: [-215 to 215 - 1], Default: 0
  • max – Type: int, Unit: 1/10 °C, Range: [-215 to 215 - 1], Default: 0

Returns the threshold as set by request/temperature_ir_bricklet/<UID>/set_object_temperature_callback_threshold.

The following symbols are available for this function:

For option:

  • "off" = "x"
  • "outside" = "o"
  • "inside" = "i"
  • "smaller" = "<"
  • "greater" = ">"
request/temperature_ir_bricklet/<UID>/set_debounce_period
Request:
  • debounce – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100
Response:
  • no response

Sets the period with which the threshold callbacks

are triggered, if the thresholds

keep being reached.

request/temperature_ir_bricklet/<UID>/get_debounce_period
Request:
  • empty payload
Response:
  • debounce – Type: int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100

Returns the debounce period as set by request/temperature_ir_bricklet/<UID>/set_debounce_period.

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the corresponding .../register/... topic and an optional suffix. This suffix can be used to deregister the callback later.

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.

register/temperature_ir_bricklet/<UID>/ambient_temperature
Register Request:
  • register – Type: bool
Callback Response:
  • temperature – Type: int, Unit: 1/10 °C, Range: [-400 to 1250]

A callback can be registered for this event by publishing to the .../register/temperature_ir_bricklet/<UID>/ambient_temperature[/<SUFFIX>] topic with the payload "true". An added callback can be removed by publishing to the same topic with the payload "false". To support multiple (de)registrations, e.g. for message filtering, an optional suffix can be used.

If the callback is triggered, a message with it's payload is published under the corresponding .../callback/temperature_ir_bricklet/<UID>/ambient_temperature[/<SUFFIX>] topic for each registered suffix.

This callback is triggered periodically with the period that is set by request/temperature_ir_bricklet/<UID>/set_ambient_temperature_callback_period. The callback payload is the ambient temperature of the sensor.

The register/temperature_ir_bricklet/<UID>/ambient_temperature callback is only triggered if the ambient temperature has changed since the last triggering.

register/temperature_ir_bricklet/<UID>/object_temperature
Register Request:
  • register – Type: bool
Callback Response:
  • temperature – Type: int, Unit: 1/10 °C, Range: [-700 to 3800]

A callback can be registered for this event by publishing to the .../register/temperature_ir_bricklet/<UID>/object_temperature[/<SUFFIX>] topic with the payload "true". An added callback can be removed by publishing to the same topic with the payload "false". To support multiple (de)registrations, e.g. for message filtering, an optional suffix can be used.

If the callback is triggered, a message with it's payload is published under the corresponding .../callback/temperature_ir_bricklet/<UID>/object_temperature[/<SUFFIX>] topic for each registered suffix.

This callback is triggered periodically with the period that is set by request/temperature_ir_bricklet/<UID>/set_object_temperature_callback_period. The callback payload is the object temperature of the sensor.

The register/temperature_ir_bricklet/<UID>/object_temperature callback is only triggered if the object temperature has changed since the last triggering.

register/temperature_ir_bricklet/<UID>/ambient_temperature_reached
Register Request:
  • register – Type: bool
Callback Response:
  • temperature – Type: int, Unit: 1/10 °C, Range: [-400 to 1250]

A callback can be registered for this event by publishing to the .../register/temperature_ir_bricklet/<UID>/ambient_temperature_reached[/<SUFFIX>] topic with the payload "true". An added callback can be removed by publishing to the same topic with the payload "false". To support multiple (de)registrations, e.g. for message filtering, an optional suffix can be used.

If the callback is triggered, a message with it's payload is published under the corresponding .../callback/temperature_ir_bricklet/<UID>/ambient_temperature_reached[/<SUFFIX>] topic for each registered suffix.

This callback is triggered when the threshold as set by request/temperature_ir_bricklet/<UID>/set_ambient_temperature_callback_threshold is reached. The callback payload is the ambient temperature of the sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by request/temperature_ir_bricklet/<UID>/set_debounce_period.

register/temperature_ir_bricklet/<UID>/object_temperature_reached
Register Request:
  • register – Type: bool
Callback Response:
  • temperature – Type: int, Unit: 1/10 °C, Range: [-700 to 3800]

A callback can be registered for this event by publishing to the .../register/temperature_ir_bricklet/<UID>/object_temperature_reached[/<SUFFIX>] topic with the payload "true". An added callback can be removed by publishing to the same topic with the payload "false". To support multiple (de)registrations, e.g. for message filtering, an optional suffix can be used.

If the callback is triggered, a message with it's payload is published under the corresponding .../callback/temperature_ir_bricklet/<UID>/object_temperature_reached[/<SUFFIX>] topic for each registered suffix.

This callback is triggered when the threshold as set by request/temperature_ir_bricklet/<UID>/set_object_temperature_callback_threshold is reached. The callback payload is the object temperature of the sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by request/temperature_ir_bricklet/<UID>/set_debounce_period.