National Instruments NI 9403E - Manual (Page 6)

NI 9403E Operating Instructions and Specifications 6 ni.com
Refer to Figure 3 for an illustration of several types of digital
devices connected to the NI 9403E.
Figure 3. Connecting Digital Devices to the NI 9403E
TTL Signal
+5 V
+5 V
LED
DIO0 as Input
DIO1 as Input
COM
DIO2 as Output
NI 9403E Dev 3
Dev 2
Dev 1