Справочник Пользователя для National Instruments NI 9144

© National Instruments Corporation

The NI 9215 has four channels with a nominal range of ±10.4 V. 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.

LSB weight is referred to as Gain in the object dictionary.

The NI 9215 EEPROM stores these two constants for each channel. The 
host can then take these constants and adjust the raw data into calibrated 
data.

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 25.  NI 9215 Calibration Coefficients

LSB Weight

Unsigned

nV/LSB

Offset

Signed

nV

Table 26.  NI 9217 Vendor Configuration Extensions

0x2001

0

ARR:U32

—

Scan List = 5

1

R

Channels to Convert = 1..4, 
default = 4

2..5

R/W

Channel Code

0x2002

0

U32

R/W

Conversion Speed Control = 2 or 31,
default = 31

(

)

(

)∗ LSB

---------

⎝

⎠

⎛

⎞∗10

9

–

-------

⎝

⎠

⎛

⎞

⎩

⎭

⎨

⎬

⎧

⎫

(

)∗10

9

–

-------

⎝

⎠

⎛

⎞

⎭

⎬

⎫

–

=