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ISA bus serial board two port RS422/485 two DB9

Provides two RS422/485 serial ports when the card is installed in an open PCI slot in your computer.


Limited Quantity In Stock
Typically Ships within One Week
Extended Double Diamond™ Warranty Available (3 Additional Year)

*Required field

Product Features


  • All cards eliminate disruptive line noise. The RS-422 and RS-485 interfaces measure the difference in electrical signals and keep this difference constant.
  • Support both 2- and 4-wire operation and distances up to 4000 feet (1219.2 m).
  • Cards are COM-1 through COM-4 addressable and also feature nonstandard I/O addressing.

  • NOTE: Cards with optical isolation are available.
    NOTE: Cards with 11 IRQs also available.

    Tech Specs

    Approvals CE
    Buffer 16-byte FIFO
    Connectors (2) DB9 M
    Distance 4000 ft. (1219.2 m) maximum
    Operating Systems Supported Windows®, Linux®, QNX
    Operation 2 or 4 wires
    Protocol Async
    Speed 115.2 kbps maximum
    This product works with:

    * Technical specification weight is the unit weight. It is not the packaged shipping weight. For shipping weight, please contact Black Box customer service at 877-877-2269.




    Double Diamond Warranty

    Extended 1 Year Warranty Available

    Protect your purchase with an additional 1 Year Double Diamond™ warranty!
    Cost: $16.00

    Extended 3 Year Warranty Available

    Protect your purchase with an additional 3 Year Double Diamond™ warranty!
    Cost: $31.99


    Double Diamond™ Warranty (Standard)

    Take the risk out of equipment purchases with the Double Diamond™ Warranty from Black Box Network Services.

    The Double Diamond Warranty is our warranty that protects your Black Box® brand products* from accidental damage, including drops, water, and power surges.

    The ISA bus serial board two port RS422/485 two DB9 comes with a standard 1 Year warranty already included.

    During the warranty period, Black Box Network Services will repair or replace your damaged equipment within one week of receipt at NO CHARGE!*

    Plus, get an Extended Double Diamond Warranty.

    You can also extend your warranty or protect a previously purchased Black Box® brand product** for an additional year—for only 10% of the purchase price! Or, extend your coverage for a full three years for only 20% of the purchase price!

    Ordering an extended warranty is easy: When viewing a product in your shopping cart, just select the one or three years of additional coverage in the dropdown menu under “Warranty Options.” For details, contact Customer Service at 724-746-5500.

    * Warranty subject to certain exclusions and limitations ** Certain products may not be eligible.

    What’s more, we also have a 45-day return policy. Simply call Customer Service for a Return Authorization (RA) number, return your product in new condition and in the original package, and receive a full refund.