Agilent Technologies VXI E1439 - Manual (Page 101)

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Agilent E1439 Programmer's Reference
Functions listed alphabetically
AGE1439_BLOCKSIZE_MAX selects the maximum blocksize.
AGE1439_BLOCKSIZE_DEF sets the default blocksize.
The range of available block sizes depends on the number of bytes required for each sample. The
command accepts any number between 2 and memory size (in bytes)
× 2/3. If the requested block
size falls outside the range shown in the table the previous valid value is used and a status register
flag (bit 6) is set indicating a setup error. The blocksize is updated after the setup is changed to be
valid.
For real data blocksize is the number of real data values per data block. For complex data
blocksize is the number of complex data pairs per data block.
The following table summarizes the available block sizes for each setting of the dataType, and
resolution parameters.
Note
Block size must be an even number. Considerably more samples may need to be taken in order to
set the block available status bit.
blocksizePtr points to the current value of the blocksize parameter. The returned value is the closest valid value
to the requested block size.
dataDelay is used to specify the minimum FIFO delay in number of samples. This parameter applies only in
continuous mode.
AGE1439_DATA_DELAY_MAX sets the maximum allowable delay.
AGE1439_DATA_DELAY_MIN sets the minimum allowable delay.
dataDelayPtr points to the current value of the delay parameter.
dataType determines whether the Agilent E1439 collects and returns real or complex data.
Setting this parameter to AGE1439_REAL causes only the real part of the data to be returned for
each sample
AGE1439_COMPLEX causes the real data followed by the imaginary data to be returned in each
sample.
Normally, if the center frequency set with the age1439_frequency_setup function is zero, the
type should be set to AGE1439_REAL since the imaginary component of each sample is zero
anyway. When non-zero center frequencies are used the type should normally be set to
AGE1439_COMPLEX, otherwise the imaginary component of the signal is lost.
data type resolution min. block size
max block size
in Msamples
(2 M*72 memory)
1
1. Parity memory is used in non-parity mode, so 2M
× 72
bit memory yields 18 Mbytes of FIFO storage.
real 12 6 12
real 24 3 6
complex 12 3 6
complex 24 2 3