Data Translation DT9820 Series, Руководство пользователя

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Chapter 4
52
Transfer Data from an In-Process Buffer
Determine the number of
buffers on the in-process
queue using
olDaGetQueueSize.
At least one buffer must exist.
Allocate a buffer of the specified
number of samples with
olDmCallocBuffer.
Copy the data from the in-process
buffer to the allocated buffer for
immediate processing using
olDaFlushFromBufferInprocess.
Deal with messages and
buffers (see page 53 ).
The buffer into which in-process data was copied
was put onto the done queue by the driver,
resulting in an OLDA_WM_BUFFER_
DONE message.
When it has been filled, the in-process buffer is
placed on the done queue and an
OLDA_WM_BUFFER_DONE message is posted.
However, the number of valid samples is equal to
the queue’s maximum samples minus what was
copied out.