National Instruments NI 6120 - Manual (Page 53)

Chapter 4 Connecting Signals
© National Instruments Corporation 4-15 NI 6115/6120 User Manual
Connecting Digital I/O Signals
The DIO signals are DIO<0..7> and DGND. DIO<0..7> are the signals
making up the DIO port, and DGND is the ground-reference signal for the
DIO port. You can program groups of individual lines to be inputs or
outputs.
Caution Exceeding the maximum input voltage ratings, which are listed in Table 4-3, can
damage the NI 6115/6120 and the computer. NI is not liable for any damage resulting from
such signal connections.
Figure 4-7 shows signal connections for three typical DIO applications.
Figure 4-7. Digital I/O Connections
+5 V
LED
TTL Signal
+5 V
Switch
I/O Connector
DGND
NI 6115/6120
DIO<0..3>
DIO<4..7>