class Tinkerforge::BrickletThermocouple

Measures temperature with thermocouples

Constants

CALLBACK_ERROR_STATE

This Callback is triggered every time the error state changes (see BrickletThermocouple#get_error_state).

CALLBACK_TEMPERATURE

This callback is triggered periodically with the period that is set by BrickletThermocouple#set_temperature_callback_period. The parameter is the temperature of the thermocouple.

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

CALLBACK_TEMPERATURE_REACHED

This callback is triggered when the threshold as set by BrickletThermocouple#set_temperature_callback_threshold is reached. The parameter is the temperature of the thermocouple.

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

Public Class Methods

new(uid, ipcon) click to toggle source

Creates an object with the unique device ID uid and adds it to the IP Connection ipcon.

Calls superclass method
# File lib/tinkerforge/bricklet_thermocouple.rb, line 76
def initialize(uid, ipcon)
  super uid, ipcon, DEVICE_IDENTIFIER, DEVICE_DISPLAY_NAME

  @api_version = [2, 0, 0]

  @response_expected[FUNCTION_GET_TEMPERATURE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_TEMPERATURE_CALLBACK_PERIOD] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_TEMPERATURE_CALLBACK_PERIOD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_TEMPERATURE_CALLBACK_THRESHOLD] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_TEMPERATURE_CALLBACK_THRESHOLD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_DEBOUNCE_PERIOD] = RESPONSE_EXPECTED_TRUE
  @response_expected[FUNCTION_GET_DEBOUNCE_PERIOD] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_SET_CONFIGURATION] = RESPONSE_EXPECTED_FALSE
  @response_expected[FUNCTION_GET_CONFIGURATION] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_ERROR_STATE] = RESPONSE_EXPECTED_ALWAYS_TRUE
  @response_expected[FUNCTION_GET_IDENTITY] = RESPONSE_EXPECTED_ALWAYS_TRUE

  @callback_formats[CALLBACK_TEMPERATURE] = [12, 'l']
  @callback_formats[CALLBACK_TEMPERATURE_REACHED] = [12, 'l']
  @callback_formats[CALLBACK_ERROR_STATE] = [10, '? ?']

  @ipcon.add_device self
end

Public Instance Methods

get_configuration() click to toggle source

Returns the configuration as set by BrickletThermocouple#set_configuration.

# File lib/tinkerforge/bricklet_thermocouple.rb, line 205
def get_configuration
  check_validity

  send_request FUNCTION_GET_CONFIGURATION, [], '', 11, 'C C C'
end
get_debounce_period() click to toggle source

Returns the debounce period as set by BrickletThermocouple#set_debounce_period.

# File lib/tinkerforge/bricklet_thermocouple.rb, line 169
def get_debounce_period
  check_validity

  send_request FUNCTION_GET_DEBOUNCE_PERIOD, [], '', 12, 'L'
end
get_error_state() click to toggle source

Returns the current error state. There are two possible errors:

  • Over/Under Voltage and

  • Open Circuit.

Over/Under Voltage happens for voltages below 0V or above 3.3V. In this case it is very likely that your thermocouple is defective. An Open Circuit error indicates that there is no thermocouple connected.

You can use the CALLBACK_ERROR_STATE callback to automatically get triggered when the error state changes.

# File lib/tinkerforge/bricklet_thermocouple.rb, line 222
def get_error_state
  check_validity

  send_request FUNCTION_GET_ERROR_STATE, [], '', 10, '? ?'
end
get_identity() click to toggle source

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). A Bricklet connected to an :ref:`Isolator Bricklet <isolator_bricklet>` is always at position 'z'.

The device identifier numbers can be found :ref:`here <device_identifier>`. |device_identifier_constant|

# File lib/tinkerforge/bricklet_thermocouple.rb, line 238
def get_identity
  send_request FUNCTION_GET_IDENTITY, [], '', 33, 'Z8 Z8 k C3 C3 S'
end
get_temperature() click to toggle source

Returns the temperature of the thermocouple.

If you want to get the temperature periodically, it is recommended to use the CALLBACK_TEMPERATURE callback and set the period with BrickletThermocouple#set_temperature_callback_period.

# File lib/tinkerforge/bricklet_thermocouple.rb, line 105
def get_temperature
  check_validity

  send_request FUNCTION_GET_TEMPERATURE, [], '', 12, 'l'
end
get_temperature_callback_period() click to toggle source

Returns the period as set by BrickletThermocouple#set_temperature_callback_period.

# File lib/tinkerforge/bricklet_thermocouple.rb, line 123
def get_temperature_callback_period
  check_validity

  send_request FUNCTION_GET_TEMPERATURE_CALLBACK_PERIOD, [], '', 12, 'L'
end
get_temperature_callback_threshold() click to toggle source

Returns the threshold as set by BrickletThermocouple#set_temperature_callback_threshold.

# File lib/tinkerforge/bricklet_thermocouple.rb, line 147
def get_temperature_callback_threshold
  check_validity

  send_request FUNCTION_GET_TEMPERATURE_CALLBACK_THRESHOLD, [], '', 17, 'k l l'
end
register_callback(id, &block) click to toggle source

Registers a callback with ID id to the block block.

# File lib/tinkerforge/bricklet_thermocouple.rb, line 243
def register_callback(id, &block)
  callback = block
  @registered_callbacks[id] = callback
end
set_configuration(averaging, thermocouple_type, filter) click to toggle source

You can configure averaging size, thermocouple type and frequency filtering.

Available averaging sizes are 1, 2, 4, 8 and 16 samples.

As thermocouple type you can use B, E, J, K, N, R, S and T. If you have a different thermocouple or a custom thermocouple you can also use G8 and G32. With these types the returned value will not be in °C/100, it will be calculated by the following formulas:

  • G8: “value = 8 * 1.6 * 2^17 * Vin“

  • G32: “value = 32 * 1.6 * 2^17 * Vin“

where Vin is the thermocouple input voltage.

The frequency filter can be either configured to 50Hz or to 60Hz. You should configure it according to your utility frequency.

The conversion time depends on the averaging and filter configuration, it can be calculated as follows:

  • 60Hz: “time = 82 + (samples - 1) * 16.67“

  • 50Hz: “time = 98 + (samples - 1) * 20“

# File lib/tinkerforge/bricklet_thermocouple.rb, line 198
def set_configuration(averaging, thermocouple_type, filter)
  check_validity

  send_request FUNCTION_SET_CONFIGURATION, [averaging, thermocouple_type, filter], 'C C C', 8, ''
end
set_debounce_period(debounce) click to toggle source

Sets the period with which the threshold callback

is triggered, if the threshold

keeps being reached.

# File lib/tinkerforge/bricklet_thermocouple.rb, line 162
def set_debounce_period(debounce)
  check_validity

  send_request FUNCTION_SET_DEBOUNCE_PERIOD, [debounce], 'L', 8, ''
end
set_temperature_callback_period(period) click to toggle source

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

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

# File lib/tinkerforge/bricklet_thermocouple.rb, line 116
def set_temperature_callback_period(period)
  check_validity

  send_request FUNCTION_SET_TEMPERATURE_CALLBACK_PERIOD, [period], 'L', 8, ''
end
set_temperature_callback_threshold(option, min, max) click to toggle source

Sets the thresholds for the CALLBACK_TEMPERATURE_REACHED callback.

The following options are possible:

"Option", "Description"

"'x'",    "Callback is turned off"
"'o'",    "Callback is triggered when the temperature is *outside* the min and max values"
"'i'",    "Callback is triggered when the temperature is *inside* the min and max values"
"'<'",    "Callback is triggered when the temperature is smaller than the min value (max is ignored)"
"'>'",    "Callback is triggered when the temperature is greater than the min value (max is ignored)"
# File lib/tinkerforge/bricklet_thermocouple.rb, line 140
def set_temperature_callback_threshold(option, min, max)
  check_validity

  send_request FUNCTION_SET_TEMPERATURE_CALLBACK_THRESHOLD, [option, min, max], 'k l l', 8, ''
end