Shell - UV Light Bricklet

This is the description of the Shell API bindings for the UV Light Bricklet. General information and technical specifications for the UV Light 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 UV Light Bricklet

# Get current UV light
tinkerforge call uv-light-bricklet $uid get-uv-light

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 UV Light Bricklet

# Handle incoming UV light callbacks
tinkerforge dispatch uv-light-bricklet $uid uv-light &

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

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

# Handle incoming UV light reached callbacks
tinkerforge dispatch uv-light-bricklet $uid uv-light-reached\
 --execute "echo UV Light: {uv_light}/10 mW/m². UV Index > 3. Use sunscreen!" &

# Configure threshold for UV light "greater than 75 mW/m²"
tinkerforge call uv-light-bricklet $uid set-uv-light-callback-threshold threshold-option-greater 750 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 uv-light-bricklet [<option>..] <uid> <function> [<argument>..]
Parameters:
  • <uid> -- string
  • <function> -- string

The call command is used to call a function of the UV Light 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 UV Light Bricklet and exits
tinkerforge dispatch uv-light-bricklet [<option>..] <uid> <callback>
Parameters:
  • <uid> -- string
  • <callback> -- string

The dispatch command is used to dispatch a callback of the UV Light 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 UV Light Bricklet and exits
tinkerforge call uv-light-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 uv-light-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 uv-light-bricklet <uid> get-uv-light
Output:
  • uv-light -- int

Returns the UV light intensity of the sensor, the intensity is given in 1/10 mW/m². The sensor has already weighted the intensity with the erythemal action spectrum to get the skin-affecting irradiation.

To get UV index you just have to divide the value by 250. For example, a UV light intensity of 500 is equivalent to an UV index of 2.

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

Advanced Functions

tinkerforge call uv-light-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 uv-light-bricklet <uid> set-uv-light-callback-period <period>
Parameters:
  • <period> -- int
Output:

no output

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

The uv-light callback is only triggered if the intensity has changed since the last triggering.

The default value is 0.

tinkerforge call uv-light-bricklet <uid> get-uv-light-callback-period
Output:
  • period -- int

Returns the period as set by set-uv-light-callback-period.

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

no output

Sets the thresholds for the uv-light-reached callback.

The following options are possible:

Option Description
'x' Callback is turned off
'o' Callback is triggered when the intensity is outside the min and max values
'i' Callback is triggered when the intensity is inside the min and max values
'<' Callback is triggered when the intensity is smaller than the min value (max is ignored)
'>' Callback is triggered when the intensity 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 uv-light-bricklet <uid> get-uv-light-callback-threshold
Output:
  • option -- char (has symbols)
  • min -- int
  • max -- int

Returns the threshold as set by set-uv-light-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 uv-light-bricklet <uid> set-debounce-period <debounce>
Parameters:
  • <debounce> -- int
Output:

no output

Sets the period in ms with which the threshold callbacks

are triggered, if the thresholds

keep being reached.

The default value is 100.

tinkerforge call uv-light-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 uv-light-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 uv-light-bricklet <uid> uv-light
Output:
  • uv-light -- int

This callback is triggered periodically with the period that is set by set-uv-light-callback-period. The parameter is the UV Light intensity of the sensor.

The uv-light callback is only triggered if the intensity has changed since the last triggering.

tinkerforge dispatch uv-light-bricklet <uid> uv-light-reached
Output:
  • uv-light -- int

This callback is triggered when the threshold as set by set-uv-light-callback-threshold is reached. The parameter is the UV Light intensity of the sensor.

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