User manual

TTL-level Digital Input/Output
The PCI-1730 has 16 TTL-level digital inputs and 16 TTL-level digital
outputs. The following figure shows connections to exchange digital
signals with other TTL devices:
DO
DI
GND
PCI-1730 TTL device
Figure 3-6: TTL-level digital input/output connection
If you want to receive an OPEN/SHORT signal from a switch or relay,
add a pull-up resistor to ensure that the input is held at a high level
when the contacts are open. See the figure below:
DI
GND
Switch
+5V
4.7K
PCI-1730
Figure 3-7: Open/short connection
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