NI 9870 4-Port, RS232 Serial Interface Module for CompactRIO

Starting at $ 548 (view pricing options)
  • 4 RS232 (TIA/EIA-232) serial ports for CompactRIO
  • Baud rates from 14 b/s to 921.6 kb/s
  • Data bits: 5, 6, 7, 8; Stop bits: 1, 1.5, 2; Flow control: XON/OFF, RTS/CTS, None
  • Individual 64 B UART FIFO buffers per port
  • 8 to 28 VDC externally powered; PC-MF4-PT cable included
  • -40 to 70 °C operating range
  • Configure Complete CompactRIO System
  • View Support Resources
The NI 9870 serial module adds four RS232 serial ports to NI CompactRIO systems. With an NI LabVIEW FPGA API, the four ports are accessed directly from the CompactRIO field-programmable gate array (FPGA) to offer you flexibility in communicating with serial devices. The module has individual 64 B buffers on every port that save CompactRIO FPGA space and simplify programming.

This C Series module supports standard start bit, stop bit, and handshaking settings, and has baud rates up to 921.6 kb/s per port. You can pass up to 1.28 Mb/s of data between the module and CompactRIO.

The NI 9870 uses an external power to provide maximum compatibility and reliability under all serial port conditions. A 35 cm female microfit to pigtail power cable is included for quick connection to the CompactRIO external power supply. The optional PC-MF4-Y C Series microfit male to 2 female Y adapter cable is available for daisy chaining multiple NI 987x module power supplies.

NI 987x C Series modules are available in a bundle with four 10P10C modular jack to DB9 (DE9) female cables for out-of-the-box connectivity.

Specifications Documents

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Specifications Summary

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To use the NI 9870 , you need all items in the diagram below. Select Option 1 if you already own a CompactRIO 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

CompactRIO System

NI 9870



NI 9870
- 779891-02 Qty $ 548 each
- 779891-03 Qty $ 712 each
- 779891-01 Qty $ 635 each
Optional Accessories
Qty $ 21 each
Qty $ 9 each
Qty $ 26 each
Qty $ 26 each
Qty $ 31 each
Qty $ 37 each
Qty $ 28 each
Qty $ 33 each
Qty $ 39 each

Subtotal: $ 548

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