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NI 9144 User Guide and Specifications
NI 9265 Calibration Data
The NI 9265 has four channels with a nominal range of 0 to 20.675 mA. Each channel has an
associated LSB weight, which is the number of volts per bit, and an offset, which is the number
of volts per bit measured when the inputs are grounded.
Note
LSB weight is referred to as Gain in the object dictionary.
The calibration data is stored in a U32 array, though each Offset field (subindex 1, 3, 5, and so
on) should be interpreted as a signed value.
Use the calibration coefficients with the following equation to generate corrected data:
where
Code
represents the code returned by the NI 9265
I
desired
represents the corrected current value
NI 9269
The vendor configuration extensions for the NI 9269 are listed in Table 98.
Table 97.
NI 9265 Scan List Format
Coefficient
Representation
Units
LSB Weight
Unsigned
pA/LSB
Offset
Signed
pA
Table 98.
NI 9269 Vendor Configuration Extensions
Index
Sub
Type
R/W
Description
0x2100
0
ARR:U32
—
Calibration = 16
1
R
Ch0 Offset
2
R
Ch0 Gain
3
R
Ch1 Offset
...
—
—
8
R
Ch3 Gain
9
R
External Ch0 Offset
...
—
—
I
desired
Code
(
)
Code LSB
weight
×
pA
bits
---------
10
12
–
×
A
pA
-------
Offset pA
(
)
10
12
–
A
pA
-------
×
+
=