National Instruments Deterministic Ethernet Expansion Chassis NI..., User Manual

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NI 9144 User Guide and Specifications 38 ni.com
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
correct data:
R
raw
( bits ) = data returned by the NI 9217 in bits
R
corrected
= calibrated resistance reading
NI 9219
Table 31. NI 9217 Calibration Coefficients
Coefficient Representation Units
LSB Weight Unsigned p
Ω/
LSB
Offset Signed
μΩ
Table 32. NI 9219 Vendor Configuration Extensions
Index Sub Type R/W Description
0x2001 0 ARR:U32 — Command List = 33
1 R Command Count = 1..32, default = 32
2..33 R/W Configuration Command
0x2002 1 ARR:U32 R Error Status
0x2005 0 U32 R/W ADC Format
R
corrected
R
raw
( )
R
raw
bits
( )∗
LSB
weight
p
Ω
bits
---------
⎝ ⎠
⎛ ⎞
∗
10
12
–
Ω
p Ω
-------
⎝ ⎠
⎛ ⎞
⎩ ⎭
⎨ ⎬
⎧ ⎫
Offset
μΩ ( )∗
10
6
–
Ω
μΩ
--------
⎝ ⎠
⎛ ⎞
– =