NI 9144 User Guide and Specifications 54 ni.com
NI 9234 Example Data Rates
The example data rates use a 12.8 MHz clock source.
NI 9234 Calibration Data
The NI 9234 has four channels with a nominal range of ± 5 V. Each channel
has an associated AC or DC input mode; an optional IEPE excitation; an
associated LSB weight, which is how many volts there are per bit; and an
offset, which is the volts per bit measured with the inputs 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 48. NI 9234 Example Data Rates
Data Rate
Clock
Divisor
Clock
Source
Rate
Byte
Oversample
Clock Rate
50.000 kS/s 00001 10 0x06 12.80 MHz
25.000 kS/s 00010 10 0x0A 6.40 MHz
16.667 kS/s 00011 10 0x0E 4.27 MHz
12.500 kS/s 00100 10 0x12 3.20 MHz
10.000 kS/s 00101 10 0x16 2.56 MHz
6.250 kS/s 01000 10 0x22 1.60 MHz
5.000 kS/s 01010 10 0x2A 1.28 MHz
Table 49. NI 9234 Scan List Format
Coefficient Representation Units
LSB Weight Unsigned pV/LSB
Offset Signed nV
Vcorrected Vraw
()Vraw bits()
∗LSBweight
pV
bits
---------
⎝⎠
⎛⎞
∗10 12–V
pV
-------
⎝⎠
⎛⎞
⎩⎭
⎨⎬
⎧⎫
Offset pV()
∗10 9–V
nV
-------
⎝⎠
⎛⎞
⎭
⎬
⎫
–=