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NI myRIO-1950 User Guide and Specifications
•
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 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-1950 has 3.3 V general-purpose DIO lines on the MXP connectors. MXP
connectors A and B have 16 DIO lines per connector. Each DIO line from 0 to 13 has a 40 kΩ
pullup resistor to 3.3 V, and DIO lines 14 and 15 have 2.1 kΩ pullup resistors to 3.3 V. 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 Interface Bus (SPI), I2C,
pulse-width modulation (PWM), and quadrature encoder input. Refer to the NI myRIO software
documentation for information about configuring the DIO lines.
Figure 6.
DIO Lines <13..0> on MXP Connector A or B
Figure 7.
DIO Lines <15..14> on MXP Connector A or B
When a DIO line is floating, it floats in the direction of the pull resistor. A DIO line may be
floating in any of the following conditions:
•
when the myRIO device is starting up
•
when the line is configured as an input
•
when the myRIO device is powering down
You can add a stronger resistor to a DIO line to cause it to float in the opposite direction.
40 k
Ω
FPGA
B
us
S
witch
DIO<1
3
..0>
+
3
.
3
V
2.1 k
Ω
FPGA
B
us
S
witch
DIO<15..14>
+
3
.
3
V
