C/C++ - Sound Intensity Bricklet – Tinkerforge

- Getting Started
  - Primer
  - Tutorials
  - FAQ
- Hardware
  - Bricks
  - Bricklets
  - Master Extensions
  - Power Supplies
  - Accessories
  - Timeline
- Software
  - Brick Daemon (brickd)
  - Brick Viewer (brickv)
  - API Bindings
    - C/C++
      - Requirements
      - Installation
      - Testing an Example
      - API Reference and Examples
        - IP Connection
        - Bricks
        - Bricklets
          - Ambient Light Bricklet
          - Analog In Bricklet
          - Analog Out Bricklet
          - Barometer Bricklet
          - Color Bricklet
          - Current12 Bricklet
          - Current25 Bricklet
          - Distance IR Bricklet
          - Distance US Bricklet
          - Dual Button Bricklet
          - Dual Relay Bricklet
          - GPS Bricklet
          - Hall Effect Bricklet
          - Humidity Bricklet
          - Industrial Digital In 4 Bricklet
          - Industrial Digital Out 4 Bricklet
          - Industrial Dual 0-20mA Bricklet
          - Industrial Quad Relay Bricklet
          - IO-16 Bricklet
          - IO-4 Bricklet
          - Joystick Bricklet
          - LCD 16x2 Bricklet
          - LCD 20x4 Bricklet
          - LED Strip Bricklet
          - Line Bricklet
          - Linear Poti Bricklet
          - Moisture Bricklet
          - Motion Detector Bricklet
          - Multi Touch Bricklet
          - NFC/RFID Bricklet
          - Piezo Buzzer Bricklet
          - Piezo Speaker Bricklet
          - PTC Bricklet
          - Remote Switch Bricklet
          - Rotary Encoder Bricklet
          - Rotary Poti Bricklet
          - Segment Display 4x7 Bricklet
          - Solid State Relay Bricklet
          - Sound Intensity Bricklet
            - Examples
              - Simple
              - Callback
              - Threshold
            - API
              - Basic Functions
              - Advanced Functions
              - Callback Configuration Functions
              - Callbacks
              - Constants
          - Temperature Bricklet
          - Temperature IR Bricklet
          - Tilt Bricklet
          - Voltage Bricklet
          - Voltage/Current Bricklet
    - C/C++ (iOS)
    - C#
    - C# (Windows Phone)
    - Delphi/Lazarus
    - Java
    - Java (Android)
    - JavaScript
    - LabVIEW
    - Mathematica
    - MATLAB/Octave
    - Perl
    - PHP
    - Python
    - Ruby
    - Shell
    - Visual Basic .NET
  - Firmwares and Plugins
  - Device Identifier
  - Source Code and Bug Tracking
  - Programming Interface
- Starter Kits
  - Weather Station
  - Hardware Hacking
  - Server Room Monitoring
  - Blinkenlights
  - Internet of Things
  - Camera Slider
- Embedded Boards
  - Raspberry Pi
- Specifications
  - Technical Data
  - TCP/IP Protocol
  - Modbus Protocol
  - Wireshark Dissector

# C/C++ - Sound Intensity Bricklet

This is the description of the C/C++ API bindings for the Sound Intensity Bricklet. General information and technical specifications for the Sound Intensity Bricklet are summarized in its hardware description.

An installation guide for the C/C++ API bindings is part of their general description.

## Examples

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

### Simple

Download (example_simple.c)

     1
     2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38

    #include <stdio.h>

    #include "ip_connection.h"
    #include "bricklet_sound_intensity.h"

    #define HOST "localhost"
    #define PORT 4223
    #define UID "XYZ" // Change to your UID

    int main() {
        // Create IP connection
        IPConnection ipcon;
        ipcon_create(&ipcon);

        // Create device object
        SoundIntensity sound_intensity;
        sound_intensity_create(&sound_intensity, UID, &ipcon);

        // Connect to brickd
        if(ipcon_connect(&ipcon, HOST, PORT) < 0) {
            fprintf(stderr, "Could not connect\n");
            exit(1);
        }
        // Don't use device before ipcon is connected

        // Get current intensity
        uint16_t intensity;
        if(sound_intensity_get_intensity(&sound_intensity, &intensity) < 0) {
            fprintf(stderr, "Could not get value, probably timeout\n");
            exit(1);
        }

        printf("Intensity: %d\n", intensity);

        printf("Press key to exit\n");
        getchar();
        ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
    }

### Callback

Download (example_callback.c)

     1
     2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47

    #include <stdio.h>

    #include "ip_connection.h"
    #include "bricklet_sound_intensity.h"

    #define HOST "localhost"
    #define PORT 4223
    #define UID "XYZ" // Change to your UID

    // Callback function for intensity
    void cb_intensity(uint16_t intensity, void *user_data) {
        (void)user_data; // avoid unused parameter warning

        printf("Intensity: %d\n", intensity);
    }

    int main() {
        // Create IP connection
        IPConnection ipcon;
        ipcon_create(&ipcon);

        // Create device object
        SoundIntensity sound_intensity;
        sound_intensity_create(&sound_intensity, UID, &ipcon);

        // Connect to brickd
        if(ipcon_connect(&ipcon, HOST, PORT) < 0) {
            fprintf(stderr, "Could not connect\n");
            exit(1);
        }
        // Don't use device before ipcon is connected

        // Set Period for intensity callback to 1s (1000ms)
        // Note: The intensity callback is only called every second if the
        //       intensity has changed since the last call!
        sound_intensity_set_intensity_callback_period(&sound_intensity, 1000);

        // Register intensity callback to function cb_intensity
        sound_intensity_register_callback(&sound_intensity,
                                          SOUND_INTENSITY_CALLBACK_INTENSITY,
                                          (void *)cb_intensity,
                                          NULL);

        printf("Press key to exit\n");
        getchar();
        ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
    }

### Threshold

Download (example_threshold.c)

     1
     2
     3
     4
     5
     6
     7
     8
     9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48

    #include <stdio.h>

    #include "ip_connection.h"
    #include "bricklet_sound_intensity.h"

    #define HOST "localhost"
    #define PORT 4223
    #define UID "XYZ" // Change to your UID

    // Callback for intensity greater than 2000
    void cb_reached(uint16_t intensity, void *user_data) {
        (void)user_data; // avoid unused parameter warning

        printf("Intensity: %d\n", intensity);
    }

    int main() {
        // Create IP connection
        IPConnection ipcon;
        ipcon_create(&ipcon);

        // Create device object
        SoundIntensity sound_intensity;
        sound_intensity_create(&sound_intensity, UID, &ipcon);

        // Connect to brickd
        if(ipcon_connect(&ipcon, HOST, PORT) < 0) {
            fprintf(stderr, "Could not connect\n");
            exit(1);
        }
        // Don't use device before ipcon is connected

        // Get threshold callbacks with a debounce time of 1 seconds (1000ms)
        sound_intensity_set_debounce_period(&sound_intensity, 1000);

        // Register threshold reached callback to function cb_reached
        sound_intensity_register_callback(&sound_intensity,
                                          SOUND_INTENSITY_CALLBACK_INTENSITY_REACHED,
                                          (void *)cb_reached,
                                          NULL);

        // Configure threshold for "greater than 2000"
        sound_intensity_set_intensity_callback_threshold(&sound_intensity, '>', 2000, 0);

        printf("Press key to exit\n");
        getchar();
        ipcon_destroy(&ipcon); // Calls ipcon_disconnect internally
    }

## API

Every function of the C/C++ bindings returns an integer which describes an error code. Data returned from the device, when a getter is called, is handled via call by reference. These parameters are labeled with the `ret_` prefix.

Possible error codes are:

- E_OK = 0
- E_TIMEOUT = -1
- E_NO_STREAM_SOCKET = -2
- E_HOSTNAME_INVALID = -3
- E_NO_CONNECT = -4
- E_NO_THREAD = -5
- E_NOT_ADDED = -6 (unused since bindings version 2.0.0)
- E_ALREADY_CONNECTED = -7
- E_NOT_CONNECTED = -8
- E_INVALID_PARAMETER = -9
- E_NOT_SUPPORTED = -10
- E_UNKNOWN_ERROR_CODE = -11

as defined in `ip_connection.h`.

All functions listed below are thread-safe.

### Basic Functions

void `sound_intensity_create`(SoundIntensity *sound_intensity, const char *uid, IPConnection *ipcon)

  Creates the device object `sound_intensity` with the unique device ID `uid` and adds it to the IPConnection `ipcon`:

      SoundIntensity sound_intensity;
      sound_intensity_create(&sound_intensity, "YOUR_DEVICE_UID", &ipcon);

  This device object can be used after the IP connection has been connected (see examples above).

void `sound_intensity_destroy`(SoundIntensity *sound_intensity)

  Removes the device object `sound_intensity` from its IPConnection and destroys it. The device object cannot be used anymore afterwards.

int `sound_intensity_get_intensity`(SoundIntensity *sound_intensity, uint16_t *ret_intensity)

  Returns the current sound intensity. The value has a range of 0 to 4095.

  The value corresponds to the upper envelop of the signal of the microphone capsule.

  If you want to get the intensity periodically, it is recommended to use the callback `SOUND_INTENSITY_CALLBACK_INTENSITY` and set the period with `sound_intensity_set_intensity_callback_period()`.

### Advanced Functions

int `sound_intensity_get_api_version`(SoundIntensity *sound_intensity, uint8_t ret_api_version[3])

  Returns the version of the API definition (major, minor, revision) implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

int `sound_intensity_get_response_expected`(SoundIntensity *sound_intensity, uint8_t function_id, bool *ret_response_expected)

  Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

  For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by `sound_intensity_set_response_expected()`. For setter functions it is disabled by default and can be enabled.

  Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

  See `sound_intensity_set_response_expected()` for the list of function ID defines available for this function.

int `sound_intensity_set_response_expected`(SoundIntensity *sound_intensity, uint8_t function_id, bool response_expected)

  Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled and callbacks it is always disabled.

  Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

  The following function ID defines are available for this function:

  - SOUND_INTENSITY_FUNCTION_SET_INTENSITY_CALLBACK_PERIOD = 2
  - SOUND_INTENSITY_FUNCTION_SET_INTENSITY_CALLBACK_THRESHOLD = 4
  - SOUND_INTENSITY_FUNCTION_SET_DEBOUNCE_PERIOD = 6

int `sound_intensity_set_response_expected_all`(SoundIntensity *sound_intensity, bool response_expected)

  Changes the response expected flag for all setter and callback configuration functions of this device at once.

int `sound_intensity_get_identity`(SoundIntensity *sound_intensity, char ret_uid[8], char ret_connected_uid[8], char *ret_position, uint8_t ret_hardware_version[3], uint8_t ret_firmware_version[3], uint16_t *ret_device_identifier)

  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. There is also a constant for the device identifier of this Bricklet.

### Callback Configuration Functions

void `sound_intensity_register_callback`(SoundIntensity *sound_intensity, uint8_t id, void *callback, void *user_data)

  Registers a callback with ID `id` to the function `callback`. The `user_data` will be given as a parameter of the callback.

  The available IDs with corresponding function signatures are listed below.

int `sound_intensity_set_intensity_callback_period`(SoundIntensity *sound_intensity, uint32_t period)

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

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

  The default value is 0.

int `sound_intensity_get_intensity_callback_period`(SoundIntensity *sound_intensity, uint32_t *ret_period)

  Returns the period as set by `sound_intensity_set_intensity_callback_period()`.

int `sound_intensity_set_intensity_callback_threshold`(SoundIntensity *sound_intensity, char option, uint16_t min, uint16_t max)

  Sets the thresholds for the `SOUND_INTENSITY_CALLBACK_INTENSITY_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 defines are available for this function:

  - SOUND_INTENSITY_THRESHOLD_OPTION_OFF = 'x'
  - SOUND_INTENSITY_THRESHOLD_OPTION_OUTSIDE = 'o'
  - SOUND_INTENSITY_THRESHOLD_OPTION_INSIDE = 'i'
  - SOUND_INTENSITY_THRESHOLD_OPTION_SMALLER = '<'
  - SOUND_INTENSITY_THRESHOLD_OPTION_GREATER = '>'

int `sound_intensity_get_intensity_callback_threshold`(SoundIntensity *sound_intensity, char *ret_option, uint16_t *ret_min, uint16_t *ret_max)

  Returns the threshold as set by `sound_intensity_set_intensity_callback_threshold()`.

  The following defines are available for this function:

  - SOUND_INTENSITY_THRESHOLD_OPTION_OFF = 'x'
  - SOUND_INTENSITY_THRESHOLD_OPTION_OUTSIDE = 'o'
  - SOUND_INTENSITY_THRESHOLD_OPTION_INSIDE = 'i'
  - SOUND_INTENSITY_THRESHOLD_OPTION_SMALLER = '<'
  - SOUND_INTENSITY_THRESHOLD_OPTION_GREATER = '>'

int `sound_intensity_set_debounce_period`(SoundIntensity *sound_intensity, uint32_t debounce)

  Sets the period in ms with which the threshold callback

  - `SOUND_INTENSITY_CALLBACK_INTENSITY_REACHED`

  is triggered, if the thresholds

  - `sound_intensity_set_intensity_callback_threshold()`

  keeps being reached.

  The default value is 100.

int `sound_intensity_get_debounce_period`(SoundIntensity *sound_intensity, uint32_t *ret_debounce)

  Returns the debounce period as set by `sound_intensity_set_debounce_period()`.

### Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the `sound_intensity_register_callback()` function. The parameters consist of the device object, the callback ID, the callback function and optional user data:

>     void my_callback(int p, void *user_data) {
>         printf("parameter: %d\n", p);
>     }

>     sound_intensity_register_callback(&sound_intensity, SOUND_INTENSITY_CALLBACK_EXAMPLE, (void *)my_callback, NULL);

The available constants with corresponding callback function signatures 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.

`SOUND_INTENSITY_CALLBACK_INTENSITY`

      void callback(uint16_t intensity, void *user_data)

  This callback is triggered periodically with the period that is set by `sound_intensity_set_intensity_callback_period()`. The parameter is the intensity of the encoder.

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

`SOUND_INTENSITY_CALLBACK_INTENSITY_REACHED`

      void callback(uint16_t intensity, void *user_data)

  This callback is triggered when the threshold as set by `sound_intensity_set_intensity_callback_threshold()` is reached. The parameter is the intensity of the encoder.

  If the threshold keeps being reached, the callback is triggered periodically with the period as set by `sound_intensity_set_debounce_period()`.

### Constants

`SOUND_INTENSITY_DEVICE_IDENTIFIER`

  This constant is used to identify a Sound Intensity Bricklet.

  The `sound_intensity_get_identity()` function and the `IPCON_CALLBACK_ENUMERATE` callback of the IP Connection have a `device_identifier` parameter to specify the Brick's or Bricklet's type.

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