TDT RZ2, Руководство пользователя

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2-34 System 3
PO8e Streaming Interface for the RZ
The data will be grouped by channel and the number of samples
returned applies to all channels. The user is responsible for
ensuring that the buffer is large enough to hold nSamples *
numChannels() * dataSampleSize() bytes. The optional offsets
array should be nSamples long and will be populated with the
data offset of each block. This allows a user to detect if the
buffer on the RZ unit has overflowed.
C++ prototype:
int readBlock( void *buffer, int nSamples,
int64_t *offsets = NULL );
C prototype:
int readBlock( void * card, void *buffer, int
nSamples, int64_t *offsets);
Arguments:
void pointer
buffer
The location to write buffered data to.
int
nSamples
The number of samples to read.
in64_t pointer
offsets
The location to write the buffer indices to.
Returns:
int Number of samples that were read.
Sample Code
Description:
This code sample reads 1 sample from all channels, stores it in
a buffer and flushes that data from the card.
C++
short buff[1024];
card->readBlock(buff, 1);
card->flushBufferedData(1);
C
short buff[1024];
readBlock(card, buff, 1);
flushBufferedData(card, 1);
flushBufferedData
Description: Releases samples from each buffered channel.
C++ prototype:
void flushBufferedData( int numSamples = -1,
bool freeBuffers = false);
C prototype:
void flushBufferedData( void * card, int
numSamples = -1, bool freeBuffers = false);
Arguments:
int
numSamples
Number of samples to release. Passing -1
releases all buffered samples.
bool
freeBuffers
Controls the optional freeing of the underlying
data buffers.
Sample Code
Description:
This code sample flushes one sample from all channels.
C++
card->flushBufferedData(1);
C
flushBufferedData(card, 1);