Data Translation DT3120, Руководство пользователя

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Chapter 2
26
Acquisition Operations
The DT3120 board can acquire interlaced frames or individual fields
either synchronously or asynchronously, and store them in system
memory. In a synchronous acquisition, you cannot perform another
operation until the synchronous acquisition completes. In an
asynchronous acquisition, the operation starts but gives control to
you immediately, allowing you to perform other operations while
data is acquired.
Using the DT3120, you can acquire a single full frame, a single field
(subframe), multiple full frames, or multiple fields. Data is stored to
an area in system memory that is allocated by the DT3120 Device
Driver (called
device memory ). Table 2 lists the memory size that is
used for each image format and image type supported.
Table 2: Memory Used
Video Format
Storage Image
Format
Maximum Memory Used
(Bytes)
60 Hz RGB or RGB24 1,228,800
RGB16 or YUYV422 614,400
MONO 307,200
50 Hz RGB or RGB24 1,769,472
RGB16 or YUYV422 884,736
MONO 442,368