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PCIe-COM-4SMDB and RJ Family

PCI Express 4 and 2-Port RS-232/422/485 Serial Communication Cards


  • Four and two-port PCI Express serial communication cards with on board DB9M or RJ45 connectivity
  • Serial protocol (RS-232/422/485) SOFTWARE CONFIGURED per port, stored in EEPROM for auto-configure at next boot
  • High performance 16C950 class UARTs with 128-byte FIFO for each transmit and receive buffer
  • Supports data communication speeds up to 3Mbps (standard model RS-232 is 460.8kbps)
  • ±15kV ESD protection on all signal pins
  • Supports 9-bit data mode
  • Full modem control signals in RS-232 mode
  • Software compatible with all operating systems
  • Selectable termination for RS-485 applications
  • Designed, made, supported, and manufactured in the USA


  • Extended temperature operation (-40° 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 on COM A

ACCES I/Os PCI Express multi-port multi-protocol serial communication cards deliver four (PCIe-COM-4SMDB, PCIe-COM-4SMRJ) or two (PCIe-COM-2SMDB, PCIe-COM-2SMRJ), 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.

Perfect for existing serial peripherals to connect directly to the industry standard pin-out of the DB9M connectors or via a RJ45 connector. 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.

Available accessories include a broad range of cables, screw terminal boards and breakout connection boxes for a variety of quick and easy connectivity options.


Please contact ACCES with your precise requirement. Examples of special orders would be conformal coating, custom software, 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 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 32-bit and 64-bit Windows.

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: DB9 or RJ45
  • Serial ports: 4 (or 2) RS-232/422/485
  • Serial data rates: RS-232=460.8k (921.6k avail); RS-422/485=3Mbps
  • UART: Quad type 16C950 with 128-byte transmit & receive FIFO, 16C550 compliant
  • ESD Protection: 15kV on all signal pins
  • Character length: 5, 6, 7, 8, or 9 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


  • 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 @ 0.8W (typical)
  • Size: 4.722" long x 3.375" high (120 mm long x 85.725 mm high)

OEM and volume pricing available, please call us.  

ModelPrice (USD)

PCIe-COM-4SMRJ PCI Express four-port RS-232/422/485
PCIe-COM-4SMDB* PCI Express four-port RS-232/422/485
PCIe-COM-4SRJ PCI Express four-port RS-422/485
PCIe-COM-4SDB* PCI Express four-port RS-422/485
PCIe-COM232-4RJ PCI Express four-port RS-232 only
PCIe-COM232-4DB* PCI Express four-port RS-232 only
PCIe-COM-2SMRJ PCI Express two-port RS-232/422/485
PCIe-COM-2SMDB PCI Express two-port RS-232/422/485
PCIe-COM-2SRJ PCI Express two-port RS-422/485
PCIe-COM-2SDB PCI Express two-port RS-422/485
PCIe-COM232-2RJ PCI Express two-port RS-232 only
PCIe-COM232-2DB PCI Express two-port RS-232 only
ADAP9Screw terminal adaptor (single DB9 female to 9 screw terminals)
ADAP9-2Screw terminal adaptor (dual DB9 female to 18 screw terminals)
Model Options:
-FFast version (RS-232 up to 921.6kbps)
-TExtended Temperature Operation (-40° to +85°C)
-RoHSRoHS compliant version
-WRemote wake-up enable
* Please note: 4-port "DB" equipped cards require a (provided) cable-to-second-backplate accessory.
Acquisition, Control, Communication: Engineering and Systems