Shell - Accelerometer Bricklet – Tinkerforge

- Getting Started
- Hardware
- Software
- Starter Kits
- Embedded Boards
- Specifications

# Shell - Accelerometer Bricklet

Note

This Bricklet is currently in the prototype stage and the software/hardware as well as the documentation is in an incomplete state.

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

    1
    2
    3
    4
    5
    6
    7
    8

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

    # change to your UID
    uid=sad

    # get current acceleration
    tinkerforge call accelerometer-bricklet $uid get-acceleration

### Callback

Download (example-callback.sh)

     1
     2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13

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

    # change to your UID
    uid=sad

    # set period for acceleration callback to 1s (1000ms)
    # note: the acceleration callback is only called every second if the
    #       acceleration has changed since the last call!
    tinkerforge call accelerometer-bricklet $uid set-acceleration-callback-period 1000

    # handle incoming acceleration callbacks
    tinkerforge dispatch accelerometer-bricklet $uid acceleration

### Threshold

Download (example-threshold.sh)

     1
     2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13
    14
    15
    16
    17
    18

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

    # change to your UID
    uid=sad

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

    # Configure threshold for acceleration values X, Y or Z greater than 2G
    tinkerforge call accelerometer-bricklet $uid set-acceleration-callback-threshold greater 2000 0 2000 0 2000 0

    # handle incoming acceleration-reached callbacks
    tinkerforge dispatch accelerometer-bricklet $uid acceleration-reached\
     --execute "echo 'Acceleration(X): {x}';
                echo 'Acceleration(Y): {y}';
                echo 'Acceleration(Z): {z}';
                echo '';"

## 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` `accelerometer-bricklet` [<option>..] <uid> <function> [<argument>..]

  Parameters:

  - <uid> -- string
  - <function> -- string

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

tinkerforge `dispatch` `accelerometer-bricklet` [<option>..] <uid> <callback>

  Parameters:

  - <uid> -- string
  - <callback> -- string

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

tinkerforge call `accelerometer-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 `accelerometer-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 `accelerometer-bricklet` <uid> `get-acceleration`

  Output:

  - x -- int
  - y -- int
  - z -- int

  Returns the acceleration in x, y and z direction. The values are given in mG (1/1000 G).

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

tinkerforge call `accelerometer-bricklet` <uid> `get-temperature`

  Output:

  - temperature -- int

  Returns the temperature of the accelerometer in °C.

tinkerforge call `accelerometer-bricklet` <uid> `led-on`

  Output: | no output

  Enables the LED on the Bricklet.

tinkerforge call `accelerometer-bricklet` <uid> `led-off`

  Output: | no output

  Disables the LED on the Bricklet.

tinkerforge call `accelerometer-bricklet` <uid> `is-led-on`

  Output:

  - value -- int

  Returns true if the LED is enabled, false otherwise.

### Advanced Functions

tinkerforge call `accelerometer-bricklet` <uid> `set-configuration` <data-rate> <full-scale> <filter-bandwidth>

  Parameters:

  - <data-rate> -- int (has symbols)
  - <full-scale> -- int (has symbols)
  - <filter-bandwidth> -- int (has symbols)

  Output: | no output

  Configures the data rate, full scale range and filter bandwidth. Possible values are:

  - Data rate of 0Hz to 1600Hz.
  - Full scale range of -2G to +2G up to -16G to +16G.
  - Filter bandwidth between 50Hz and 800Hz.

  Decreasing data rate or full scale range will also decrease the noise on the data.

  The default values are 100Hz data rate, -4G to +4G range and 200Hz filter bandwidth.

  The following symbols are available for this function:

  - `off` = 0, for <data-rate>
  - `3hz` = 1, for <data-rate>
  - `6hz` = 2, for <data-rate>
  - `12hz` = 3, for <data-rate>
  - `25hz` = 4, for <data-rate>
  - `50hz` = 5, for <data-rate>
  - `100hz` = 6, for <data-rate>
  - `400hz` = 7, for <data-rate>
  - `800hz` = 8, for <data-rate>
  - `1600hz` = 9, for <data-rate>
  - `2g` = 0, for <full-scale>
  - `4g` = 1, for <full-scale>
  - `6g` = 2, for <full-scale>
  - `8g` = 3, for <full-scale>
  - `16g` = 4, for <full-scale>
  - `800hz` = 0, for <filter-bandwidth>
  - `400hz` = 1, for <filter-bandwidth>
  - `200hz` = 2, for <filter-bandwidth>
  - `50hz` = 3, for <filter-bandwidth>

tinkerforge call `accelerometer-bricklet` <uid> `get-configuration`

  Output:

  - data-rate -- int (has symbols)
  - full-scale -- int (has symbols)
  - filter-bandwidth -- int (has symbols)

  Returns the configuration as set by `set-configuration`.

  The following symbols are available for this function:

  - `off` = 0, for data-rate
  - `3hz` = 1, for data-rate
  - `6hz` = 2, for data-rate
  - `12hz` = 3, for data-rate
  - `25hz` = 4, for data-rate
  - `50hz` = 5, for data-rate
  - `100hz` = 6, for data-rate
  - `400hz` = 7, for data-rate
  - `800hz` = 8, for data-rate
  - `1600hz` = 9, for data-rate
  - `2g` = 0, for full-scale
  - `4g` = 1, for full-scale
  - `6g` = 2, for full-scale
  - `8g` = 3, for full-scale
  - `16g` = 4, for full-scale
  - `800hz` = 0, for filter-bandwidth
  - `400hz` = 1, for filter-bandwidth
  - `200hz` = 2, for filter-bandwidth
  - `50hz` = 3, for filter-bandwidth

tinkerforge call `accelerometer-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 `accelerometer-bricklet` <uid> `set-acceleration-callback-period` <period>

  Parameters:

  - <period> -- int

  Output: | no output

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

  `acceleration` is only triggered if the acceleration has changed since the last triggering.

  The default value is 0.

tinkerforge call `accelerometer-bricklet` <uid> `get-acceleration-callback-period`

  Output:

  - period -- int

  Returns the period as set by `set-acceleration-callback-period`.

tinkerforge call `accelerometer-bricklet` <uid> `set-acceleration-callback-threshold` <option> <min-x> <max-x> <min-y> <max-y> <min-z> <max-z>

  Parameters:

  - <option> -- char (has symbols)
  - <min-x> -- int
  - <max-x> -- int
  - <min-y> -- int
  - <max-y> -- int
  - <min-z> -- int
  - <max-z> -- int

  Output: | no output

  Sets the thresholds for the `acceleration-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, 0, 0, 0, 0).

  The following symbols are available for this function:

  - `off` = x, for <option>
  - `outside` = o, for <option>
  - `inside` = i, for <option>
  - `smaller` = <, for <option>
  - `greater` = >, for <option>

tinkerforge call `accelerometer-bricklet` <uid> `get-acceleration-callback-threshold`

  Output:

  - option -- char (has symbols)
  - min-x -- int
  - max-x -- int
  - min-y -- int
  - max-y -- int
  - min-z -- int
  - max-z -- int

  Returns the threshold as set by `set-acceleration-callback-threshold`.

  The following symbols are available for this function:

  - `off` = x, for option
  - `outside` = o, for option
  - `inside` = i, for option
  - `smaller` = <, for option
  - `greater` = >, for option

tinkerforge call `accelerometer-bricklet` <uid> `set-debounce-period` <debounce>

  Parameters:

  - <debounce> -- int

  Output: | no output

  Sets the period in ms with which the threshold callback

  - `acceleration-reached`

  is triggered, if the threshold

  - `set-acceleration-callback-threshold`

  keeps being reached.

  The default value is 100.

tinkerforge call `accelerometer-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 accelerometer-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 `accelerometer-bricklet` <uid> `acceleration`

  Output:

  - x -- int
  - y -- int
  - z -- int

  This callback is triggered periodically with the period that is set by `set-acceleration-callback-period`. The parameters are the X, Y and Z acceleration.

  `acceleration` is only triggered if the acceleration has changed since the last triggering.

tinkerforge dispatch `accelerometer-bricklet` <uid> `acceleration-reached`

  Output:

  - x -- int
  - y -- int
  - z -- int

  This callback is triggered when the threshold as set by `set-acceleration-callback-threshold` is reached. The parameters are the X, Y and Z acceleration.

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

The content of this page is licensed under Creative Commons Attribution 3.0 Unported License.