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NI 9401 5 V/TTL, Bidirectional Digital I/O, 8 Ch Module

Starting at $ 296 (view pricing options)
The NI 9401 is an 8-channel, 100 ns bidirectional digital input module for any NI CompactDAQ or CompactRIO chassis. You can configure the direction of the digital lines on the NI 9401 for input or output by nibble (4 bits). Thus, you can program the NI 9401 for three configurations: eight digital inputs, eight digital outputs, or four digital inputs and four digital outputs. With reconfigurable I/O (RIO) technology (CompactRIO only), you can use the LabVIEW FPGA Module to program the NI 9401 for implementing custom, high-speed counter/timers; digital communication protocols; pulse generation; and much more. Each channel is compatible with 5 V/TTL signals and features 1,000 Vrms transient isolation between the I/O channels and the backplane.

Recommended Accessories
-The NI 9924 (or other 25-pin D-SUB connector)

EMC Performance
To ensure EMC compliance, you must use a ferrite bead, such as NI part number 782803-01.

Box Contents
-1 NI 9401 C Series module
-1 NI 9401 Operating Instructions and Specifications manual

Specifications Documents

  • View Data Sheet

Specifications Summary


To use the NI 9401 , you need all items in the diagram below. Select Option 1 if you already own a C Series System, or Option 2 if you do not already own a chassis, controller, or software.

Roll over the icons below to learn why you need each item in the system

C Series System

1 Terminal Block


NI 9401




NI 9401 and Accessories Only
NI 9401
- 779351-01 Qty $ 296 each
- 782401-01 Qty $ 431 each
Required Accessories
Qty $ 103 each
EMI Suppression Ferrite for NI 9401 (qty 1) - 782803-01
Qty $ 4 each

Subtotal: $ 403

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Select a Platform and Configure a System

Create a complete system with the NI 9401 and its accessories. However, the NI 9401 is compatible with multiple C Series Platforms, NI CompactDAQ and CompactRIO. Please review the comparison information below and select a platform to begin configuring your system.

Configure System Configure System

NI CompactDAQ NI CompactRIO
Mixed-Measurement Data Acquisition

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Time-Critical Control & Monitoring

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Features NI CompactDAQ NI CompactRIO
USB, Wi-Fi, Ethernet, Headless Operation Ethernet, Headless Operation
Up to -40 to 70 C Up to 50 g shock and 5 grms operational vibration Up to -40 to 70 C Up to 50 g shock and 5 grms operational vibration
LabVIEW, LabVIEW Real-Time, C, C++, VB.NET, C#.NET LabVIEW, LabVIEW Real-Time, LabVIEW FPGA, C, C++
NI-DAQmx driver; configuration and troubleshooting tools; short time to first measurement NI-RIO driver; flexibility and customizabilty
PC-based data acquisition; embedded data-logging; portable and benchtop Single-point acquisition; closed-loop control; deterministic operation

Service Programs for Hardware

At NI, we produce high-performance hardware and are committed to helping you maintain that performance for years to come. Our three- or five-year service programs for hardware and systems provide the coverage you need while ensuring lowest total cost of ownership over the life of your system:

  • Get up and running faster with system assembly and configuration services
  • Operate on a fixed budget with prepaid repair and calibration services
  • Maintain peak performance with a discounted calibration plan
  • Simply call us to schedule your service—no budget approval needed

To learn more about service programs for hardware and systems, see

Technical Support

With the knowledge, experience, and responsiveness of NI applications engineers in more than 30 languages and 40 countries, we have the technical support resources to ensure your success. Through our standard NI technical support program, we can help you:

  • Consult on how to use NI products
  • Overcome development challenges
  • Quickly resolve issues pre- or post-deployment

To access NI technical support services for your hardware, visit

Training and Certification

With extensive training options for new and experienced users, we can help you reduce development time and costs through faster learning and increased productivity with your NI hardware and systems. Gain the skills you need to design and develop high-quality applications:

  • Learn recommended techniques to reduce development time and improve application performance and scalability
  • Leverage more than 40 training courses taught by NI and industry experts
  • Attend training in a variety of formats, including online, virtual, and classroom settings

To find training courses for your hardware, visit

Consulting and Integration

NI and the extensive network of NI Alliance Partners provide a wide range of professional services so that together, we can assist you with the design, development, and deployment of even the most complex systems. Take advantage of the team’s in-depth knowledge of NI products and applications with the following services:

  • Prototyping and feasibility analysis
  • Startup, consulting, and development assistance
  • System integration
  • Migration and upgrade assistance

For more information on NI professional services and the Alliance Partner Network, see