Signal
Description
NC
No connection
Table 1. Signal Descriptions
Ports
The DIO channels are grouped in two ports, one containing channels 0, 1, 2, and 3,
and one containing channels 4, 5, 6, and 7. You can independently configure each
digital port in software for input or output. Note that all four channels in the port
must share the same line direction.
Connecting a Serial Peripheral Interface Device
You can connect a Serial Peripheral Interface (SPI) device to the NI-9401.
Figure 3. Connecting an SPI Device to the NI-9401
Connecting Digital Devices
You can connect several types of digital devices to the NI-9401.
Figure 4. Connecting Digital Devices to the NI-9401
Overcurrent/Short-Circuit Protection
The overcurrent protection allows only a specified amount of current through the
output channels to protect the NI-9401 from short circuits. If the NI-9401 goes into
an overcurrent state, the module sets all the DIO channels to high impedance for
approximately 280 ms.
ni.com
8
NI-9401 Getting Started
