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NI 9144 User Guide and Specifications
So, for example, the scan list entry
0x00010008
indicates this scan stores at address 1, and the
conversion two in the future is channel 3 (bit 3 set = 8).
Table 6 contains the default scan list.
NI 9201/9221 Calibration Data
The NI 9201/9221 modules have eight channels with a nominal range of ±10.53 V and ±62.5 V,
respectively. 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:
Table 6.
NI 9201/9221 Default Scan List
Index
Sub
Type
Value
0x2001
0
ARR:U32
9
1
8
2
0x00000004
3
0x00010008
4
0x00020010
5
0x00030020
6
0x00040040
7
0x00050080
8
0x00060001
9
0x00070002
Table 7.
NI 9221/9201 Calibration Coefficients
Coefficient
Representation
Units
LSB Weight
Unsigned
nV/LSB
Offset
Signed
nV
Vcorrected Vraw
(
)
Vraw bits
(
)
LSBweight
nV
bits
----------
10
9
–
V
nV
-------
×
×
Offset nV
(
)
10
9
–
V
nV
-------
×
–
=