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4-port, RS-232/422/485 serial communications board

DNx-SL-501, DNA-SL-501, DNR-SL-501, DNF-SL-501


  • 4 independent ports with custom baud rates per port
  • Arbitrary baud rate selection (0.01% accuracy)
  • Max speed of 256 Kb/s for RS-232 and 2 Mb/s for RS-485
  • J1587/J1708 support included
  • Each port is software-configurable as RS-232 or RS-485
  • Completely independent bit rate settings for every port
  • 350 V isolation between ports, ports and circuitry; 15 kV ESD
  • Compatible with RS-422 networks when used in RS-485 mode
  • Includes UEI-RSS Remote Serial Server application, Windows and Linux versions
4-port, RS-232/422/485 serial communications board
Product Style: What do the "DNx" prefixes mean? "DNA" prefix is for a Cube & MIL Cube Board, "DNR" prefix is for a Rack & MIL Rack Board , and "DNF" prefix is for a FLATRACK board.
Software/Programming: How UEI solutions are used. Hosted - Connected to a PC with Windows, Linux, QNX, VxWorks, RTX, or similar OS. Hosted also is for OPC-UA, Modbus and EtherCAT. Standalone - Controller with Linux or VxWorks OS, Simulink I/O Target or UEILogger. Available options for this product are shown in the drop down menu.
Quantity: $900
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Typically in stock for shipment in 3-4 weeks. Subject to global supply chain challenges.

DNx-SL-501, DNA-SL-501, DNR-SL-501, DNF-SL-501

The DNx-SL-501 are 4-port serial communications layers for UEI’s powerful Cube, RACKtangle and FLATRACK I/O chassis. The boards offer fully isolated serial interfaces, software-configurable as RS-232 or RS-485.

DNx-SL-501 supports up to 2 Mbit/s transfer speed in RS-485 mode or up to 256 Kb/s in RS-232 mode. A special version of the board, designated as the DNx-SL-501-804, supports baud rates up to 4 Mbit/s. The boards use a 16550C UART emulation on each port (FIFO mode only) and support
half- and full-duplex mode over RS-485.

The DNx-SL-501 is compatible with RS-422 networks when used in RS-485 mode. The layer provides 200Ω software-selectable TX and/or RX termination for RS-485 communications. The DNx-SL-501 is an ideal solution for connecting serial based data acquisition devices to the Ethernet, as well as interfacing to a wide variety of serial based devices and legacy DAQ systems. In addition to standard serial I/O features, the DNx-SL-501 offers a series of additional functions. These functions include:

  • Fully customizable baud rates generated by programmable PLL on per-channel basis from 300baud to 2Mbaud
  • Programmable inter-character delay (required to drive/simulate some avionics instruments)\Programmable inter-frame delay (used to schedule frames at different rate)
  • Automatic repeat of the last frame if new data is not sent from the host on time (required to keep “inop” flag happy on many avionic devices)
  • None/Even/Odd/Space/Mark parity in 8-bit mode and per-symbol programmable in 9-bit mode
  • Automatic in-hardware or software flow control
  • Asynchronous event mode with loop closure in 100us (for avionics expecting immediate reply)
  • Echo suppression in half-duplex mode (for 422 mode)
  • Timeout programmable in 10us, 100us or 1ms intervals

Software is included, providing a comprehensive, yet easy-to-use API that supports all popular operating systems, including Windows, Linux, and most real-time operating systems—such as QNX, Intime, VXworks, and more. Additionally, the UEIDAQ Framework—an even higher level Windows driver—supplies complete support for those creating applications in many popular Windows programming languages, as well as data acquisition software packages such as LabVIEW and MATLAB/Simulink.

Finally, the DNx-SL-501-804 includes the UEI-RSS Remote Serial Server. The RSS allows the SL-501 slots to be configured as standard “Com” ports in both Windows and Linux environments.



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