Appendix A
Connecting I/O Signals
R Series Intelligent DAQ User Manual
A-4
ni.com
To access the signals on the I/O connectors, you must connect a cable from
the I/O connector to a signal accessory. Plug the small VHDCI connector
end of the cable into the appropriate I/O connector and connect the other
end of the cable to the appropriate signal accessory.
Table A-1.
I/O Connector Signal Descriptions
Signal Name
Reference
Direction
Description
+5V
DGND
Output
+5 VDC Source—These pins supply 5 V from the computer
power supply. For more information on the +5V terminals,
refer to the
section in Chapter 2,
Hardware Overview of the NI 78xxR
.
Analog Signals (NI 783
x
R/784
x
R/785
x
R Only)
AI<0..7>+
AIGND
Input
Positive input for Analog Input channels 0 through 7.
AI<0..7>–
AIGND
Input
Negative input for Analog Input channels 0 through 7.
AIGND
—
—
Analog Input Ground—These pins are the reference point
for single-ended measurements in RSE configuration and
the bias current return point for differential measurements.
All three ground references—AIGND, AOGND, and
DGND—are connected to each other on the
NI 783
x
R/784
x
R/785
x
R.
AISENSE
AIGND
Input
Analog Input Sense—This pin serves as the reference node
for AI <0..7> when the device is configured for NRSE mode.
AO<0..7>
AOGND
Output
Analog Output channels 0 through 7. Each channel can
source or sink up to 2.5 mA.
AOGND
—
—
Analog Output Ground—The analog output voltages
are referenced to this node. All three ground
references—AIGND, AOGND, and DGND—are
connected to each other on the NI 783
x
R/784
x
R/785
x
R.
Digital Signals (All NI 78
xx
R Devices)
DGND
—
—
Digital Ground—These pins supply the reference for the
digital signals at the I/O connector and the 5 V supply.
All three ground references—AIGND, AOGND, and
DGND—are connected to each other on the
NI 783
x
R/784
x
R/785
x
R.
DIO<0..39>
Connector<0..3>
(NI 781
x
R)
DIO<0..15>
Connector 0
(NI 783
x
R/784
x
R/785
x
R)
DIO<0..39>
Connector <1..2>
(NI 783
x
R/784
x
R/785
x
R)
DGND
Input or
Output
Digital I/O signals.
Summary of Contents for NI 781 R Series
Page 1: ...PXI 7842...
