Stanford Research Systems SR865A, Operation Manual

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Chapter 4 Programming 139
SR865A DSP Lock-in Amplifier
numbers based on the value of CAPTURECFG . Querying with n=0 returns the oldest data
from the buffer.
Example
CAPTUREVAL? 3 returns the data from position 3 (the 4
th
sample)
CAPTUREGET? [ i ], [ j ]
The CAPTUREGET? query returns all or part of the capture buffer contents as a binary
block. The binary block returns j kbytes of capture buffer contents beginning with an
offset of i kbytes. If (i+j) is longer than
CAPTURELEN , then CAPTUREGET returns
wrapped data.
The maximum length j is 64 (corresponding to 64 kbytes). Both parameters i and j must
be provided. Capture must be stopped when executing
CAPTUREGET? or a range error
is generated.
The binary block query response is in the following format:
#nccccxxxxxxx
Where “
#
” is the hash character (character code 35), “
n
” is a single digit specifying the
number of digits to follow in the block length count; “
cccc
” is the
n
– digit integer size of
the binary block to follow, and “ xxxxxxx ” is the cccc –
byte binary data. Data is packed
as 4-byte (32-bit) single precision floating point binary, in little endian format.
Example
CAPTUREGET? 0,32 returns a binary block with 32 kbytes of capture data