NI myRIO-1900, User Manual And Specifications, Page: 10 / 32

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NI myRIO-1900 User Guide and Specifications
Converting Raw Data Values to Voltage
You can use the following equations to convert raw data values to volts:
V = Raw Data Value * LSB Weight
LSB Weight = Nominal Range ÷ 2 ADC Resolution
where Raw Data Value is the value returned by the FPGA I/O Node,
LSB Weight is the value in volts of the increment between data values,
Nominal Range is the absolute value in volts of the full, peak-to-peak nominal range
of the channel,
and
ADC Resolution is the resolution of the ADC in bits. ( ADC Resolution = 12.)
• For AI and AO channels on the MXP connectors,
LSB Weight = 5 V ÷ 2 12 = 1.221 mV
Maximum reading = 4095 * 1.221 mV = 4.999 V
• For AI and AO channels on the MSP connectors,
LSB Weight = 20 V ÷ 2
12
= 4.883 mV
Maximum Positive Reading = +2047 * 4.883 mV = 9.995 V
Maximum Negative Reading = -2048 * 4.883 mV = -10.000 V
• For Audio In/Out,
LSB Weight = 5 V ÷ 2 12 = 1.221 mV
Maximum Positive Reading = +2047 * 1.221 mV = 2.499 V
Maximum Negative Reading = -2048 * 1.221 mV = -2.500 V
• For the accelerometer,
LSB Weight = 16 g ÷ 2
12
= 3.906 mg
Maximum Positive Reading = +2047 * 3.906 mg = +7.996 g
Maximum Negative Reading = -2048 * 3.906 mg = -8.000 g
DIO Lines
The NI myRIO-1900 has 3.3 V general-purpose DIO lines on the MXP and MSP connectors.
MXP connectors A and B have 16 DIO lines per connector. On the MXP connectors, each DIO
line from 0 to 13 has a 40 k
Ω pullup resistor to 3.3 V, and DIO lines 14 and 15 have 2.2 k Ω
pullup resistors to 3.3 V. MSP connector C has eight DIO lines. Each MSP DIO line has a 40 k Ω
pulldown resistor to ground. DGND is the reference for all the DIO lines. You can program all
the lines individually as inputs or outputs. Secondary digital functions include Serial Peripheral