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NI 9144 User Guide and Specifications
NI 9219 ADC Format
The NI 9219 converts at different rates, and can specify different data formatting styles. This is
determined by both the ADC Format field and corresponding fields in the setup commands. The
format of the ADC Format field is shown in Table 53.
Standard values for ADC format are:
•
0x0001000F, High-Speed
•
0x000B000F, Best 60 Hz rejection
•
0x000D000F, Best 50 Hz rejection
•
0x0032000F, High-Resolution
NI 9219 Error Status
Caution
Configuring all the channels in Full-Bridge mode shorts the channels and
results in the firmware setting all the bits in the lower nibble.
When a channel over-current condition occurs on any of the channels of the NI 9219 (such as,
configure channels in 4-wire resistance mode and do not connect a resistor to the channel), the
firmware sets a bit in the lower nibble indicating the presence of this condition (LSB = ch0).
Errors are automatically internally acknowledged on the cycle after the error is reported.
NI 9219 Calibration Data
The NI 9219 has four channels which each have 21 different operating modes and ranges. 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.
Table 53.
NI 9219 ADC Format
Bits
Field
31..24
Reserved
23..16
Conversion speed in multiples of 10 mS
15..8
Reserved
7..0
ADC Data Formatting
