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PCI Express Multi-Port Multi-Protocol Low Profile Serial Communication Cards


  • Eight or four-port PCI Express serial communication cards
  • Serial protocol (RS-232/422/485) SOFTWARE CONFIGURED per port, stored in EEPROM for auto-configure at next boot
  • Low profile PCIe MD2 form factor, works in standard height or low-profile PCIe computers
  • High performance 16C950 class UARTs with 128-byte FIFO for each TX and RX
  • Supports data communication speeds up to 3Mbps (standard model RS-232 is 460.8kbps)
  • ±15kV ESD protection on all signal pins
  • Full modem control signals in RS-232 mode
  • Software compatible with all operating systems
  • Jumper selectable termination per port for RS-485 applications
  • 3' breakout cable included, terminating with industry-standard DB9M connectors (no external breakout box required)
  • Designed, made, supported, and manufactured in the USA


  • Also available in RS-485 and RS-422 only versions
  • Connector strengthening bracket for secure and fail-proof cable connections
  • Extended temperature operation (-40°C to +85°C)
  • High-speed RS-232 version up to 921.6kbps
  • RoHS compliant version
  • Support for Wind River VxWorks (call for ordering information)
  • Remote wake-up enable
  • Low profile bracket installed for small, embeddeded PCs

ACCES I/Os PCI Express multi-port multi-protocol serial communication cards deliver eight (PCIe-COM-8SM) or four (PCIe-COM-4SM), high-speed serial communication ports for use in a wide variety of applications. The cards were designed to offer serial compatibility with the PCI Express bus and to be used by system integrators and manufacturers in the design of industrial and commercial systems. Each COM port is capable of supporting data rates up to 3Mbps and implements full modem control signals in RS-232 mode to ensure compatibility with a broad variety of serial devices. The card features a x1 lane PCI Express connector which can be used in any available x1, x2, x4, x8, x12, or x16 PCI Express expansion slot.

The card is 6.6 inches in length and 2.2 inches seated height and complies with the MD2 Low Profile Form Factor specifications. Low profile PCI Express allows the design of small footprint, low profile systems while still offering expandability and upgradeability to the end user. A regular profile mounting bracket is installed for use in standard size computers, while an optional low profile bracket is provided for smaller systems which require the use of low profile PCI Express cards.

Typical serial peripherals can connect directly to the industry standard DB9M connectors on an optional breakout cable (see Ordering Guide). For DB9 pin-compatibility with legacy RS-485 systems that use our LPCI and PCI-COM485-8 cards and breakout cables, order the "NC" card model and breakout cable CAB-PCIe-485-8 (see DB9M RS-485 Pin Table)


Custom baud rates are available upon request. Please contact ACCES with your precise requirement. Other examples of special orders would be conformal coating, custom software, RJ45 connectivity, longer breakout cables, etc., we will work with you to provide exactly what is required.


A complete driver support package is provided including an easy-to-use Windows terminal program for testing out your COM ports. This simplifies the verification of proper COM port operation. The card installs as standard COM ports in all operating systems including DOS, Linux (including Mac OS X) and Windows XP -> 10, both 32 & 64 bit.

Available Reference Manuals

Available Software Downloads

Available Datasheets

Drivers and Downloads

Full list of available Downloads: Software Packages, Drivers, Manuals, and other documents

Custom Software

ACCES also offers Custom Software Services for our products. Our prices are unbelievably low, often as inexpensive as free! If you need something tweaked to support your needs, or an entire enterprise application developed from scratch, it is definitely worth your time to inquire with us, first.

Further information about available ACCES Software:

Redistributing Windows Drivers
A list of ACCES drivers and the files that compose them under different versions of Windows, so you can easily redistribute ACCES cards and drivers.


ACCES has successfully partnered with Wind River to bring our entire line of PCI and PCI Express Serial Communication cards to VxWorks 7! All ACCES plug-and-play serial cards are now supported with our VxWorks driver, including RS232, RS422, RS485 (2- and 4-wire) and baud rates up to 10Mbps.

Designed as an update to the existing vxbPciNs16550Sio.c driver, we've added support for ×8 baud rates, proper handling of the unique register location of the 4th port in the Pericom PI7C9X7954 UART, and configuring the serial protocol from your application software.

With this driver suite all ACCES PCI, PCI Express, PCI Express Mini Card, M.2, PCI-104, PCIe/104, and all related "PCI Style" plug-and-play serial cards will detect and install as standard VxWorks SIO ports.

    Asynchronous Communications Interface

  • I/O connection
    VHDCI 68 pin SCSI connector
  • Serial ports
    8 RS-232/422/485
  • Serial data rates
    RS-232 460.8k (921.6 avail), RS-422/485 3M baud
  • UART
    Octal type 16C950 with 128-byte transmit & receive FIFO, 16C550 compliant
  • ESD Protection
    ±15kV on all signal pins
  • Character length
    5, 6, 7, or 8 bits
  • Parity
    Even, Odd, None, Space, Mark
  • Stop interval
    1, 1.5, or 2 bits
  • Flow Control
    RTS/CTS and/or DSR/DTR, Xon/Xoff
  • Cable
    3' shielded breakout cable terminated with 8 male D-sub 9-pin connectors
  • Environmental

  • Operating temperature
    Commercial: 0°C to +70°C
  • Industrial: -40°C to +85°C
  • Storage temperature
    -65°C to +150°C
  • Humidity
    5% to 95%, non-condensing
  • Power required
    +3.3VDC @ 0.9W (typical)
  • Size
    6.6 inches long x 2.20 inches high, (167.64 mm long x 55.8 mm high)
ModelPrice (USD)

PCIe-COM-8SM PCI Express eight-port RS-232/422/485 serial card with 3 DB9M breakout cable
PCIe-COM-8SMNCPCI Express eight-port RS-232/422/485 serial card without cable
PCIe-COM-4SM PCI Express four-port RS-232/422/485 serial card with 3 DB9M breakout cable
PCIe-COM-4SMNCPCI Express four-port RS-232/422/485 serial card without cable
PCIe-COM422-8 PCI Express eight-port RS-422 serial card with 3 DB9M breakout cable
PCIe-COM422-8NCPCI Express eight-port RS-422 serial card without cable
PCIe-COM422-4 PCI Express four-port RS-422 serial card with 3 DB9M breakout cable
PCIe-COM422-4NCPCI Express four-port RS-422 serial card without cable
PCIe-COM485-8 PCI Express eight-port RS-485 serial card with 3 DB9M breakout cable
PCIe-COM485-8NCPCI Express eight-port RS-485 serial card without cable
PCIe-COM485-4 PCI Express four-port RS-485 serial card with 3 DB9M breakout cable
PCIe-COM485-4NCPCI Express four-port RS-485 serial card without cable
BRKT-551-SCBConnector stabilizer bracket (for use with standard height PCIe bracket only) $19
ADAP9Screw terminal adaptor (single DB9 female to 9 screw terminals)
ADAP9-2Screw terminal adaptor (dual DB9 female to 18 screw terminals)
CAB-PCIe-485-8Cable with legacy RS-485 pinout $30
Model Options:
-FFast version (RS-232 up to 921.6kbps)
-TExtended Temperature Operation (-40° to +85°C)
-RoHSRoHS compliant version
-WRemote wake-up enable
-LLow profile bracket installed
Acquisition, Control, Communication: Engineering and Systems