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3.

Select the 32-bit offset value (to be interpreted as a signed int) for a 
particular range.

4.

Use the above final coefficients and complete the following steps in the 
quadratic equation to convert raw 16-bit data into scaled volts:

a.

a0 = (f64(a0) * rangeGain) + rangeOffset

b.

a1 = f64(a1) * rangeGain

c.

a2 = f64(a2) * rangeGain

d.

a3 = f64(a3) * rangeGain

5.

Use the following formula with a3–a0 to obtain the scaled 16-bit value 
in Volts.

x =signed un-scaled 16-bit data read from device:

It is also possible to decode the raw data using only the offset and gain 
values. For more information, refer to the 

 section of this 

guide.

The scan list is a simple list of channels to convert, in order. The NI 9211 
has six channels total that can be measured:

•

0..3: Four input channels (always measured in a ±80 mV range)

•

4: One cold junction channel (always measured in a ±2.5 V range)

•

5: One auto zero channel (always measured in a ±80 mV range)

Table 18.  NI 9211 Vendor Configuration Extensions

0x2001

0

ARR:U32

—

Scan List = 7

1

R

Channels to 
Convert = 1..6,
default = 6

2..7

R/W

Channel Number