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PCIe-ICM Family

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


  • 4 and 2-port PCI Express serial communication cards with DB9M connectivity
  • 2kV isolation port-to-port and port to computer on ALL signals
  • 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 (RS-232 up to 921.6 kbps)
  • Virtually any custom baud rate may be configured by the user via register settings, no custom oscillator needed
  • ±15kV ESD protection on all signal pins
  • 9-bit data mode and RS-485 full-duplex (4-wire) fully supported
  • Full modem control signals in RS-232 mode
  • Software compatible with all operating systems
  • Selectable termination for RS422 or RS-485 applications
  • Designed, made, supported, and manufactured in the USA


  • High-speed RS-232 version up to 921.6kbps
  • Extended temperature operation (-40°C to +85°C)
  • RS-422/485 only versions
  • Remote Wake-Up Enable
  • RoHS compliant version
  • Support for Wind River VxWorks (call for ordering information)

The PCIe-ICM Series are a new family of isolated PCI Express serial communication cards. These PCI Express cards feature a selection of 4 or 2-ports of isolated, software selectable, RS-232, RS-422, and RS-485 serial protocols. 2kV isolation is provided between channels and between the PC and bus lines on ALL signals. The cards feature a x1 lane PCI Express connector which can be used in any available x1, x2, x4, x8, x12, or x16 PCI Express expansion slot.

Each RS-232 port is capable of supporting data communication rates up to 921.6 kbps and implement full modem control signals to ensure compatibility with a broad variety of serial devices. RS-422 and RS-485 modes support data communication speeds up to 3 Mbps. Existing serial peripherals can connect directly to industry standard DB9M connectors which are provided on-board each card.

The PCIe-ICM cards were designed using type 16C950 UARTS and use 128-byte transmit/receive FIFO buffers to decrease CPU loading and protect against lost data in multitasking systems. New systems can continue to use legacy serial peripherals, yet benefit from the use of the high performance PCI Express bus. The cards are fully software compatible with current PCI 16550 type UART applications and allow for users to maintain backward compatibility.

The PCIe-ICM Series is especially useful in applications where high common-mode external voltages are present. Isolation is required to guard electronics from transient voltage spikes and offers greater common-mode noise rejection in electrically noisy surroundings containing industrial machinery and inductive loads. These applications include factory automation, energy management, military/mission-critical, industrial ON/OFF control, security systems, manufacturing test, process monitoring, and kiosks. In addition to protecting industrial applications from accidental contact with high external voltages, the isolation provided eliminates troublesome ground loops.

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


  • Retail
  • Hospitality
  • Automation
  • Medical
  • Gaming
  • Shipboard
  • Defense
  • Point of Sale (POS)
  • Kiosks


Please contact ACCES with your precise requirement. Examples of special orders would be conformal coating, custom software, RJ45 connectivity, etc.


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 cards install as standard COM ports in all operating systems including DOS, Linux (including Mac OS X) and Windows XP -> 10, both 32 & 64 bit (32 and 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: DB9
  • Serial ports: 4 (or 2) RS-232/422/485
  • Isolation: 2000V port to port, port to computer
  • 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), +12VDC @ 0.9W (typical)
  • Size: 6.600" long x 4.200" high (167.65 mm long x 106.68 mm high)

OEM and volume pricing available, please call us.  

ModelPrice (USD)

PCIe-ICM-4SM* Isolated PCI Express four-port RS-232/422/485
PCIe-ICM-4S* Isolated PCI Express four-port RS-422/485
PCIe-ICM232-4* Isolated PCI Express four-port RS-232 only
PCIe-ICM-2SM Isolated PCI Express two-port RS-232/422/485
PCIe-ICM-2S Isolated PCI Express two-port RS-422/485
PCIe-ICM232-2 Isolated 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