Shell - Barometer Bricklet¶

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 Barometer Bricklet

# Get current air pressure
tinkerforge call barometer-bricklet $uid get-air-pressure

# Get current altitude
tinkerforge call barometer-bricklet $uid get-altitude

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 Barometer Bricklet

# Handle incoming air pressure callbacks
tinkerforge dispatch barometer-bricklet $uid air-pressure &

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

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

# Handle incoming air pressure reached callbacks
tinkerforge dispatch barometer-bricklet $uid air-pressure-reached\
 --execute "echo Air Pressure: {air_pressure}/1000 hPa. Enjoy the potentially good weather!" &

# Configure threshold for air pressure "greater than 1025 hPa"
tinkerforge call barometer-bricklet $uid set-air-pressure-callback-threshold threshold-option-greater 1025000 0

echo "Press key to exit"; read dummy

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

Command Structure¶

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

tinkerforge call barometer-bricklet [<option>..] <uid> <function> [<argument>..]¶

Parameters:	<uid> – Type: String <function> – Type: String

The call command is used to call a function of the Barometer 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 Barometer Bricklet and exits

tinkerforge dispatch barometer-bricklet [<option>..] <uid> <callback>¶

Parameters:	<uid> – Type: String <callback> – Type: String

The dispatch command is used to dispatch a callback of the Barometer 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 Barometer Bricklet and exits

tinkerforge call barometer-bricklet <uid> <function> [<option>..] [<argument>..]¶

Parameters:	<uid> – Type: String <function> – Type: 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 sent and errors are silently ignored, because they cannot be detected.

tinkerforge dispatch barometer-bricklet <uid> <callback> [<option>..]¶

Parameters:	<uid> – Type: String <callback> – Type: 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 barometer-bricklet <uid> get-air-pressure¶

Output:	air-pressure – Type: Int, Unit: 1/1000 hPa, Range: [10000 to 1200000]

Returns the air pressure of the air pressure sensor.

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

tinkerforge call barometer-bricklet <uid> get-altitude¶

Output:	altitude – Type: Int, Unit: 1 cm, Range: [-231 to 231 - 1]

Returns the relative altitude of the air pressure sensor. The value is calculated based on the difference between the current air pressure and the reference air pressure that can be set with set-reference-air-pressure.

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

tinkerforge call barometer-bricklet <uid> set-reference-air-pressure <air-pressure>¶

Parameters:	<air-pressure> – Type: Int, Unit: 1/1000 hPa, Range: [0, 10000 to 1200000], Default: 1013250
Output:	no output

Sets the reference air pressure for the altitude calculation. Setting the reference to the current air pressure results in a calculated altitude of 0cm. Passing 0 is a shortcut for passing the current air pressure as reference.

Well known reference values are the Q codes QNH and QFE used in aviation.

tinkerforge call barometer-bricklet <uid> get-reference-air-pressure¶

Output:	air-pressure – Type: Int, Unit: 1/1000 hPa, Range: [10000 to 1200000], Default: 1013250

Returns the reference air pressure as set by set-reference-air-pressure.

Advanced Functions¶

tinkerforge call barometer-bricklet <uid> get-chip-temperature¶

Output:	temperature – Type: Int, Unit: 1/100 °C, Range: [-4000 to 8500]

Returns the temperature of the air pressure sensor.

This temperature is used internally for temperature compensation of the air pressure measurement. It is not as accurate as the temperature measured by the Temperature Bricklet or the Temperature IR Bricklet.

tinkerforge call barometer-bricklet <uid> set-averaging <moving-average-pressure> <average-pressure> <average-temperature>¶

Parameters:	<moving-average-pressure> – Type: Int, Range: [0 to 25], Default: 25 <average-pressure> – Type: Int, Range: [0 to 10], Default: 10 <average-temperature> – Type: Int, Range: [0 to 255], Default: 10
Output:	no output

Sets the different averaging parameters. It is possible to set the length of a normal averaging for the temperature and pressure, as well as an additional length of a moving average for the pressure. The moving average is calculated from the normal averages. There is no moving average for the temperature.

Setting the all three parameters to 0 will turn the averaging completely off. If the averaging is off, there is lots of noise on the data, but the data is without delay. Thus we recommend to turn the averaging off if the Barometer Bricklet data is to be used for sensor fusion with other sensors.

New in version 2.0.1 (Plugin).

tinkerforge call barometer-bricklet <uid> get-averaging¶

Output:	moving-average-pressure – Type: Int, Range: [0 to 25], Default: 25 average-pressure – Type: Int, Range: [0 to 10], Default: 10 average-temperature – Type: Int, Range: [0 to 255], Default: 10

Returns the averaging configuration as set by set-averaging.

New in version 2.0.1 (Plugin).

tinkerforge call barometer-bricklet <uid> set-i2c-mode <mode>¶

Parameters:	<mode> – Type: Int, Range: See symbols, Default: 0
Output:	no output

Sets the I2C mode. Possible modes are:

• 0: Fast (400kHz)
• 1: Slow (100kHz)

If you have problems with obvious outliers in the Barometer Bricklet measurements, they may be caused by EMI issues. In this case it may be helpful to lower the I2C speed.

It is however not recommended to lower the I2C speed in applications where a high throughput needs to be achieved.

The following symbols are available for this function:

For <mode>:

• i2c-mode-fast = 0
• i2c-mode-slow = 1

New in version 2.0.3 (Plugin).

tinkerforge call barometer-bricklet <uid> get-i2c-mode¶

Output:	mode – Type: Int, Range: See symbols, Default: 0

Returns the I2C mode as set by set-i2c-mode.

The following symbols are available for this function:

For mode:

• i2c-mode-fast = 0
• i2c-mode-slow = 1

New in version 2.0.3 (Plugin).

tinkerforge call barometer-bricklet <uid> get-identity¶

Output:

uid – Type: String, Length: up to 8 connected-uid – Type: String, Length: up to 8 position – Type: Char, Range: [a to h, z] hardware-version – Type: Int Array, 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 Array, 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]

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 Isolator Bricklet is always at position 'z'.

The device identifier numbers can be found here. 

Callback Configuration Functions¶

tinkerforge call barometer-bricklet <uid> set-air-pressure-callback-period <period>¶

Parameters:	<period> – Type: Int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Output:	no output

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

The air-pressure callback is only triggered if the air pressure has changed since the last triggering.

tinkerforge call barometer-bricklet <uid> get-air-pressure-callback-period¶

Output:	period – Type: Int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Returns the period as set by set-air-pressure-callback-period.

tinkerforge call barometer-bricklet <uid> set-altitude-callback-period <period>¶

Parameters:	<period> – Type: Int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Output:	no output

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

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

tinkerforge call barometer-bricklet <uid> get-altitude-callback-period¶

Output:	period – Type: Int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

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

tinkerforge call barometer-bricklet <uid> set-air-pressure-callback-threshold <option> <min> <max>¶

Parameters:	<option> – Type: Char, Range: See symbols, Default: x <min> – Type: Int, Unit: 1/1000 hPa, Range: [-231 to 231 - 1], Default: 0 <max> – Type: Int, Unit: 1/1000 hPa, Range: [-231 to 231 - 1], Default: 0
Output:	no output

Sets the thresholds for the air-pressure-reached callback.

The following options are possible:

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

The following symbols are available for this function:

For <option>:

• threshold-option-off = x
• threshold-option-outside = o
• threshold-option-inside = i
• threshold-option-smaller = <
• threshold-option-greater = >

tinkerforge call barometer-bricklet <uid> get-air-pressure-callback-threshold¶

Output:	option – Type: Char, Range: See symbols, Default: x min – Type: Int, Unit: 1/1000 hPa, Range: [-231 to 231 - 1], Default: 0 max – Type: Int, Unit: 1/1000 hPa, Range: [-231 to 231 - 1], Default: 0

Returns the threshold as set by set-air-pressure-callback-threshold.

The following symbols are available for this function:

For option:

• threshold-option-off = x
• threshold-option-outside = o
• threshold-option-inside = i
• threshold-option-smaller = <
• threshold-option-greater = >

tinkerforge call barometer-bricklet <uid> set-altitude-callback-threshold <option> <min> <max>¶

Parameters:	<option> – Type: Char, Range: See symbols, Default: x <min> – Type: Int, Unit: 1 cm, Range: [-231 to 231 - 1], Default: 0 <max> – Type: Int, Unit: 1 cm, Range: [-231 to 231 - 1], Default: 0
Output:	no output

Sets the thresholds for the altitude-reached callback.

The following options are possible:

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

The following symbols are available for this function:

For <option>:

• threshold-option-off = x
• threshold-option-outside = o
• threshold-option-inside = i
• threshold-option-smaller = <
• threshold-option-greater = >

tinkerforge call barometer-bricklet <uid> get-altitude-callback-threshold¶

Output:	option – Type: Char, Range: See symbols, Default: x min – Type: Int, Unit: 1 cm, Range: [-231 to 231 - 1], Default: 0 max – Type: Int, Unit: 1 cm, Range: [-231 to 231 - 1], Default: 0

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

The following symbols are available for this function:

For option:

• threshold-option-off = x
• threshold-option-outside = o
• threshold-option-inside = i
• threshold-option-smaller = <
• threshold-option-greater = >

tinkerforge call barometer-bricklet <uid> set-debounce-period <debounce>¶

Parameters:	<debounce> – Type: Int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100
Output:	no output

Sets the period with which the threshold callbacks

• air-pressure-reached,
• altitude-reached

are triggered, if the thresholds

• set-air-pressure-callback-threshold,
• set-altitude-callback-threshold

keep being reached.

tinkerforge call barometer-bricklet <uid> get-debounce-period¶

Output:	debounce – Type: Int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100

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 barometer-bricklet <uid> example

The available callbacks are described below.

tinkerforge dispatch barometer-bricklet <uid> air-pressure¶

Output:	air-pressure – Type: Int, Unit: 1/1000 hPa, Range: [10000 to 1200000]

This callback is triggered periodically with the period that is set by set-air-pressure-callback-period. The parameter is the air pressure of the air pressure sensor.

The air-pressure callback is only triggered if the air pressure has changed since the last triggering.

tinkerforge dispatch barometer-bricklet <uid> altitude¶

Output:	altitude – Type: Int, Unit: 1 cm, Range: [-231 to 231 - 1]

This callback is triggered periodically with the period that is set by set-altitude-callback-period. The parameter is the altitude of the air pressure sensor.

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

tinkerforge dispatch barometer-bricklet <uid> air-pressure-reached¶

Output:	air-pressure – Type: Int, Unit: 1/1000 hPa, Range: [10000 to 1200000]

This callback is triggered when the threshold as set by set-air-pressure-callback-threshold is reached. The parameter is the air pressure of the air pressure sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by set-debounce-period.

tinkerforge dispatch barometer-bricklet <uid> altitude-reached¶

Output:	altitude – Type: Int, Unit: 1 cm, Range: [-231 to 231 - 1]

This callback is triggered when the threshold as set by set-altitude-callback-threshold is reached. The parameter is the altitude of the air pressure sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by set-debounce-period.