Module: | SoundCard |
Name: | Sound card |
Type: | DAQ |
Source: | daq_SoundCard.so |
Version: | 0.7 |
Author: | Roman Savochenko, Maxim Lysenko (2009) |
Description: | Provides an access to the sound card. |
License: | GPL |
This module is designed to provide data from the inputs of sound cards of the system. The module is based on the multi-platform library of work with sound PortAudio(http://www.portaudio.com). The feature of this library is the unified API, which allows you to easily adapt this module to work on different platforms and even different audio subsystems on a single platform.
Structure of the module is the reflection of the object "Controller" of subsystem "Data acquisition" on a separate audio input device available in the system. The object "Parameter" of the subsystem "Data acquisition" reflects a separate channel available from the sound input device to the attribute "val". The most functional is to use the attribute "val" in conjunction with the archive, or at least with its buffer. In the case of the archiving enabling data of the channel of audio input are placed in the buffer of the archive by the packages with the frequency of data fetch of input device that allows you to perform further operations on that data. In addition, the last package value is installed as the current value of the attribute. In the case of archive absence operation of the last package value placing as the current value of the attribute is performed only.
Also, the module implements the functions of the horizontal reservation, namely, working in conjunction with the remote station of the same level.
To add an audio input device the controller is created and configured in the system OpenSCADA. Example of the configuration tab of the controller is depicted in Figure 1.
From this tab you can set:
To add a channel of input sound device the parameter of controller is created and configured in the system OpenSCADA. Example of the configuration tab of the parameter is depicted in Figure 2.
From this tab you can set:
Tab of attributes of the parameter has the form presented in Figure 3, the tab of the values of the attribute's archive "val" is presented in Fig.4.