This is the description of the Shell API bindings for the CO2 Bricklet. General information and technical specifications for the CO2 Bricklet are summarized in its hardware description.
An installation guide for the Shell API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
1#!/bin/sh
2# Connects to localhost:4223 by default, use --host and --port to change this
3
4uid=XYZ # Change XYZ to the UID of your CO2 Bricklet
5
6# Get current CO2 concentration
7tinkerforge call co2-bricklet $uid get-co2-concentration
Download (example-callback.sh)
1#!/bin/sh
2# Connects to localhost:4223 by default, use --host and --port to change this
3
4uid=XYZ # Change XYZ to the UID of your CO2 Bricklet
5
6# Handle incoming CO2 concentration callbacks
7tinkerforge dispatch co2-bricklet $uid co2-concentration &
8
9# Set period for CO2 concentration callback to 1s (1000ms)
10# Note: The CO2 concentration callback is only called every second
11# if the CO2 concentration has changed since the last call!
12tinkerforge call co2-bricklet $uid set-co2-concentration-callback-period 1000
13
14echo "Press key to exit"; read dummy
15
16kill -- -$$ # Stop callback dispatch in background
Download (example-threshold.sh)
1#!/bin/sh
2# Connects to localhost:4223 by default, use --host and --port to change this
3
4uid=XYZ # Change XYZ to the UID of your CO2 Bricklet
5
6# Get threshold callbacks with a debounce time of 10 seconds (10000ms)
7tinkerforge call co2-bricklet $uid set-debounce-period 10000
8
9# Handle incoming CO2 concentration reached callbacks
10tinkerforge dispatch co2-bricklet $uid co2-concentration-reached &
11
12# Configure threshold for CO2 concentration "greater than 750 ppm"
13tinkerforge call co2-bricklet $uid set-co2-concentration-callback-threshold threshold-option-greater 750 0
14
15echo "Press key to exit"; read dummy
16
17kill -- -$$ # Stop callback dispatch in background
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
The common options of the call and dispatch commands are documented
here. The specific command structure is shown below.
| Parameters: |
|
|---|
The call command is used to call a function of the CO2 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 CO2 Bricklet and exits
| Parameters: |
|
|---|
The dispatch command is used to dispatch a callback of the CO2 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 CO2 Bricklet and exits
| Parameters: |
|
|---|
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.
| Parameters: |
|
|---|
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)
| Output: |
|
|---|
Returns the measured CO2 concentration.
If you want to get the CO2 concentration periodically, it is recommended to use
the co2-concentration callback and set the period with
set-co2-concentration-callback-period.
| Output: |
|
|---|
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.
| Parameters: |
|
|---|---|
| Output: |
|
Sets the period with which the co2-concentration callback is
triggered periodically. A value of 0 turns the callback off.
The co2-concentration callback is only triggered if the CO2 concentration
has changed since the last triggering.
| Output: |
|
|---|
Returns the period as set by set-co2-concentration-callback-period.
| Parameters: |
|
|---|---|
| Output: |
|
Sets the thresholds for the co2-concentration-reached callback.
The following options are possible:
Option |
Description |
|---|---|
'x' |
Callback is turned off |
'o' |
Callback is triggered when the CO2 concentration is outside the min and max values |
'i' |
Callback is triggered when the CO2 concentration is inside the min and max values |
'<' |
Callback is triggered when the CO2 concentration is smaller than the min value (max is ignored) |
'>' |
Callback is triggered when the CO2 concentration 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 = >
| Output: |
|
|---|
Returns the threshold as set by set-co2-concentration-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 = >
| Parameters: |
|
|---|---|
| Output: |
|
Sets the period with which the threshold callbacks
are triggered, if the thresholds
keep being reached.
| Output: |
|
|---|
Returns the debounce period as set by set-debounce-period.
Callbacks can be used to receive time critical or recurring data from the device:
tinkerforge dispatch co2-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.
| Output: |
|
|---|
This callback is triggered periodically with the period that is set by
set-co2-concentration-callback-period. The parameter is the CO2
concentration of the sensor.
The co2-concentration callback is only triggered if the CO2 concentration
has changed since the last triggering.
| Output: |
|
|---|
This callback is triggered when the threshold as set by
set-co2-concentration-callback-threshold is reached.
The parameter is the CO2 concentration.
If the threshold keeps being reached, the callback is triggered periodically
with the period as set by set-debounce-period.