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NI 9144 User Guide and Specifications
NI 9229/9239
The vendor configuration extensions for the NI 9229/9239 are listed in Table 67.
As a DSA module, the NI 9229/9239 does not synchronize to other modules and free-runs at its
own fixed rate.
For more information, refer to the
NI 9233 Configure ADC
section of this user guide.
Note
The NI 9229/9239 does not have the Turbo Bit configuration byte.
NI 9229/9239 Calibration Data
The NI 9229/9239 have four channels with nominal ranges of ±10 V and ±60 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.
Table 67.
NI 9229/9239 Vendor Configuration Extensions
Index
Sub
Type
R/W
Description
0x2002
0
U32
R/W
Configure ADC,
default = 0x06
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
...
—
—
Table 68.
NI 9229/9239 Scan List Format
Coefficient
Representation
Units
LSB Weight
Unsigned
pV/LSB
Offset
Signed
nV
