Download Data Acquisition Toolbox User`s Guide

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Getting Started with the Data Acquisition Toolbox
The Data Acquisition Engine
The data acquisition engine (or just engine) is a MEX-file dynamic link library
(DLL) file that:
• Stores the device objects and associated property values that control your
data acquisition application
• Controls the synchronization of events
• Controls the storage of acquired or queued data
While the engine performs these tasks, you can use MATLAB for other tasks
such as analyzing acquired data. In other words, the engine and MATLAB are
asynchronous. The relationship between acquiring data, outputting data, and
data flow is described below.
The Flow of Acquired Data
Acquiring data means that data is flowing from your hardware device into the
data acquisition engine where it is temporarily stored in memory. The data is
stored temporarily because it can be overwritten. The rate at which the data is
overwritten depends on several factors including the available memory, the
rate at which data is acquired, and the number of hardware channels from
which data is acquired.
The stored data is not automatically available in the MATLAB workspace.
Instead, you must explicitly extract data from the engine using the getdata
function.
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