Shell - Thermocouple Bricklet

This is the description of the Shell API bindings for the Thermocouple Bricklet. General information and technical specifications for the Thermocouple Bricklet are summarized in its hardware description.

An installation guide for the Shell API bindings is part of their general description.

Examples

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

Simple

Download (example-simple.sh)

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#!/bin/sh
# Connects to localhost:4223 by default, use --host and --port to change this

uid=XYZ # Change XYZ to the UID of your Thermocouple Bricklet

# Get current temperature
tinkerforge call thermocouple-bricklet $uid get-temperature

Callback

Download (example-callback.sh)

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#!/bin/sh
# Connects to localhost:4223 by default, use --host and --port to change this

uid=XYZ # Change XYZ to the UID of your Thermocouple Bricklet

# Handle incoming temperature callbacks
tinkerforge dispatch thermocouple-bricklet $uid temperature &

# Set period for temperature callback to 1s (1000ms)
# Note: The temperature callback is only called every second
#       if the temperature has changed since the last call!
tinkerforge call thermocouple-bricklet $uid set-temperature-callback-period 1000

echo "Press key to exit"; read dummy

kill -- -$$ # Stop callback dispatch in background

Threshold

Download (example-threshold.sh)

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#!/bin/sh
# Connects to localhost:4223 by default, use --host and --port to change this

uid=XYZ # Change XYZ to the UID of your Thermocouple Bricklet

# Get threshold callbacks with a debounce time of 10 seconds (10000ms)
tinkerforge call thermocouple-bricklet $uid set-debounce-period 10000

# Handle incoming temperature reached callbacks
tinkerforge dispatch thermocouple-bricklet $uid temperature-reached &

# Configure threshold for temperature "greater than 30 °C"
tinkerforge call thermocouple-bricklet $uid set-temperature-callback-threshold threshold-option-greater 3000 0

echo "Press key to exit"; read dummy

kill -- -$$ # Stop callback dispatch in background

API

Possible exit codes for all tinkerforge commands are:

  • 1: interrupted (ctrl+c)
  • 2: syntax error
  • 21: Python 2.5 or newer is required
  • 22: Python argparse module is missing
  • 23: socket error
  • 24: other exception
  • 25: invalid placeholder in format string
  • 26: authentication error
  • 201: timeout occurred
  • 209: invalid argument value
  • 210: function is not supported
  • 211: unknown error

Command Structure

The common options of the call and dispatch commands are documented here. The specific command structure is shown below.

tinkerforge call thermocouple-bricklet [<option>..] <uid> <function> [<argument>..]
Parameters:
  • <uid> -- string
  • <function> -- string

The call command is used to call a function of the Thermocouple Bricklet. It can take several options:

  • --help shows help for the specific call command and exits
  • --list-functions shows a list of known functions of the Thermocouple Bricklet and exits
tinkerforge dispatch thermocouple-bricklet [<option>..] <uid> <callback>
Parameters:
  • <uid> -- string
  • <callback> -- string

The dispatch command is used to dispatch a callback of the Thermocouple Bricklet. It can take several options:

  • --help shows help for the specific dispatch command and exits
  • --list-callbacks shows a list of known callbacks of the Thermocouple Bricklet and exits
tinkerforge call thermocouple-bricklet <uid> <function> [<option>..] [<argument>..]
Parameters:
  • <uid> -- string
  • <function> -- string

The <function> to be called can take different options depending of its kind. All functions can take the following options:

  • --help shows help for the specific function and exits

Getter functions can take the following options:

  • --execute <command> shell command line to execute for each incoming response (see section about output formatting for details)

Setter functions can take the following options:

  • --expect-response requests response and waits for it

The --expect-response option for setter functions allows to detect timeouts and other error conditions calls of setters as well. The device will then send a response for this purpose. If this option is not given for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

tinkerforge dispatch thermocouple-bricklet <uid> <callback> [<option>..]
Parameters:
  • <uid> -- string
  • <callback> -- string

The <callback> to be dispatched can take several options:

  • --help shows help for the specific callback and exits
  • --execute <command> shell command line to execute for each incoming response (see section about output formatting for details)

Basic Functions

tinkerforge call thermocouple-bricklet <uid> get-temperature
Output:
  • temperature -- int

Returns the temperature of the thermocouple. The value is given in °C/100, e.g. a value of 4223 means that a temperature of 42.23 °C is measured.

If you want to get the temperature periodically, it is recommended to use the temperature callback and set the period with set-temperature-callback-period.

Advanced Functions

tinkerforge call thermocouple-bricklet <uid> set-configuration <averaging> <thermocouple-type> <filter>
Parameters:
  • <averaging> -- int (has symbols)
  • <thermocouple-type> -- int (has symbols)
  • <filter> -- int (has symbols)
Output:

no output

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

The default configuration is 16 samples, K type and 50Hz.

The following symbols are available for this function:

  • averaging-1 = 1, for <averaging>
  • averaging-2 = 2, for <averaging>
  • averaging-4 = 4, for <averaging>
  • averaging-8 = 8, for <averaging>
  • averaging-16 = 16, for <averaging>
  • type-b = 0, for <thermocouple-type>
  • type-e = 1, for <thermocouple-type>
  • type-j = 2, for <thermocouple-type>
  • type-k = 3, for <thermocouple-type>
  • type-n = 4, for <thermocouple-type>
  • type-r = 5, for <thermocouple-type>
  • type-s = 6, for <thermocouple-type>
  • type-t = 7, for <thermocouple-type>
  • type-g8 = 8, for <thermocouple-type>
  • type-g32 = 9, for <thermocouple-type>
  • filter-option-50hz = 0, for <filter>
  • filter-option-60hz = 1, for <filter>
tinkerforge call thermocouple-bricklet <uid> get-configuration
Output:
  • averaging -- int (has symbols)
  • thermocouple-type -- int (has symbols)
  • filter -- int (has symbols)

Returns the configuration as set by set-configuration.

The following symbols are available for this function:

  • averaging-1 = 1, for averaging
  • averaging-2 = 2, for averaging
  • averaging-4 = 4, for averaging
  • averaging-8 = 8, for averaging
  • averaging-16 = 16, for averaging
  • type-b = 0, for thermocouple-type
  • type-e = 1, for thermocouple-type
  • type-j = 2, for thermocouple-type
  • type-k = 3, for thermocouple-type
  • type-n = 4, for thermocouple-type
  • type-r = 5, for thermocouple-type
  • type-s = 6, for thermocouple-type
  • type-t = 7, for thermocouple-type
  • type-g8 = 8, for thermocouple-type
  • type-g32 = 9, for thermocouple-type
  • filter-option-50hz = 0, for filter
  • filter-option-60hz = 1, for filter
tinkerforge call thermocouple-bricklet <uid> get-error-state
Output:
  • over-under -- bool
  • open-circuit -- bool

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 error-state callback to automatically get triggered when the error state changes.

tinkerforge call thermocouple-bricklet <uid> get-identity
Output:
  • uid -- string
  • connected-uid -- string
  • position -- char
  • hardware-version -- int,int,int
  • firmware-version -- int,int,int
  • device-identifier -- int (has symbols)

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

Callback Configuration Functions

tinkerforge call thermocouple-bricklet <uid> set-temperature-callback-period <period>
Parameters:
  • <period> -- int
Output:

no output

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

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

The default value is 0.

tinkerforge call thermocouple-bricklet <uid> get-temperature-callback-period
Output:
  • period -- int

Returns the period as set by set-temperature-callback-period.

tinkerforge call thermocouple-bricklet <uid> set-temperature-callback-threshold <option> <min> <max>
Parameters:
  • <option> -- char (has symbols)
  • <min> -- int
  • <max> -- int
Output:

no output

Sets the thresholds for the 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)

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

The following symbols are available for this function:

  • threshold-option-off = x, for <option>
  • threshold-option-outside = o, for <option>
  • threshold-option-inside = i, for <option>
  • threshold-option-smaller = <, for <option>
  • threshold-option-greater = >, for <option>
tinkerforge call thermocouple-bricklet <uid> get-temperature-callback-threshold
Output:
  • option -- char (has symbols)
  • min -- int
  • max -- int

Returns the threshold as set by set-temperature-callback-threshold.

The following symbols are available for this function:

  • threshold-option-off = x, for option
  • threshold-option-outside = o, for option
  • threshold-option-inside = i, for option
  • threshold-option-smaller = <, for option
  • threshold-option-greater = >, for option
tinkerforge call thermocouple-bricklet <uid> set-debounce-period <debounce>
Parameters:
  • <debounce> -- int
Output:

no output

Sets the period in ms with which the threshold callback

is triggered, if the threshold

keeps being reached.

The default value is 100.

tinkerforge call thermocouple-bricklet <uid> get-debounce-period
Output:
  • debounce -- int

Returns the debounce period as set by set-debounce-period.

Callbacks

Callbacks can be used to receive time critical or recurring data from the device:

tinkerforge dispatch thermocouple-bricklet <uid> example

The available callbacks 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.

tinkerforge dispatch thermocouple-bricklet <uid> temperature
Output:
  • temperature -- int

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

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

tinkerforge dispatch thermocouple-bricklet <uid> temperature-reached
Output:
  • temperature -- int

This callback is triggered when the threshold as set by 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 set-debounce-period.

tinkerforge dispatch thermocouple-bricklet <uid> error-state
Output:
  • over-under -- bool
  • open-circuit -- bool

This Callback is triggered every time the error state changes (see get-error-state).