Memwrite.vi – Measurement Computing UL for NI LabVIEW User Manual
Page 93

Universal Library Virtual Instruments (VIs)
Memory board VIs
MemWrite.VI
Writes data from an array to the memory card.
Summary:
Inputs:
BoardNum
[U32] - The board number assigned when installed with InstaCal. Can
be 0 to 100.
DataBuffer
[U16] - Pointer to the data array.
FirstPoint
[I32] - Index of first point to write or
FROMHERE
.
Count
[I32] - Number of samples (words) to write.
Output:
ErrCode
[I32] - Error code. See ErrMsg.VI
Arguments:
BoardNum
The board number associated with a board when it was installed with InstaCal.
DataBuffer
Buffer containing data to be written to the external memory board.
FirstPoint
Use
the
FirstPoint
argument to specify where in the board's memory to write the
first point. For example, to write to locations #200 - #250, set
FirstPoint
=200 and
Count
=50.
To write a large amount of data to the board in small portions, set
FirstPoint
to
FROMHERE
(-1) to write each successive portion. Using
FROMHERE
(-1) speeds up the
operation of MemWrite when working with large amounts of data.
Count
Specifies the number of words to be written to the external memory card.
Count
must be equal to or less than the size of
DataBuffer
.
ErrCode
Error code from the Universal Library. Zero if no error occurred. Use the ErrMsg
VI to convert
ErrCode
into a readable string.
Notes:
DT Connect conflicts - The MemWrite VI can not be called while a DT Connect transfer is in progress. For
example, if you start collecting A/D data to the memory board in the background (by calling AInScBg.VI or
AInScFg.VI with the
DTCONNECT
+
BACKGROUND
options). You can not call MemWrite until the AInScBg.VI or
AInScFg.VI has completed. If you do you will get a
DTACTIVE
error.
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