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mPCIe-ICM232-4 and mPCIe-ICM232-2

Four and two-port isolated RS232 PCI Express Mini Cards


  • PCI Express Mini Card (mPCIe) type F1, with latching I/O connectors
  • 4 or 2-port mPCIe RS232 serial cards with optional DB9M connectivity
  • Using advanced technology with 2500V isolators per UL1577
  • High performance 16C950 class UARTs with 128-byte FIFO for each transmit and receive buffer
  • Supports data communication rates to 921.6kbps
  • Virtually any custom baud rate may be configured by the user via register settings, no custom oscillator needed
  • 500V isolation port-to-port and 1500V isolation port-to-computer on ALL signals
  • ±15kV ESD protection on all signal pins
  • Supports 9-bit data mode
  • Supports CTS and RTS
  • RoHS and Industrial Temp (-40°C to +85°C) both standard
  • Designed, made, supported, and manufactured in the USA
  • Support for Wind River VxWorks (call for ordering information)

The mPCIe-ICM232 family of cards feature high performance 16C950-class UARTs. Available in 4-port (mPCIe-ICM232-4) and 2-port (mPCIe-ICM232-2) versions, each port is capable of communication speeds up to 921.6kbps and has 128-byte deep transmit and receive FIFOs which protect against data loss in multitasking operating systems, reduce CPU utilization, and improve data throughput. The advanced integrated circuit with pre-scalar supports a wide variety of custom baud rates, and any rates not otherwise achievable can be supported via a custom factory-installed crystal oscillator.

The RS232 ports provided by the card are 100% compatible with every other industry-standard serial COM device, supporting TX, RX, RTS, and CTS. In addition, they provide Tru-Iso™ port-to-port and port-to-PC isolation.

Communication is possible either with custom application software, with off-the-shelf applications (such as HyperTerminal), or with provided samples and utilities, including WinRISC™ (“Windows Really Incredibly Simple Communication).

The serial ports on the device are accessed using a low-profile, latching, 5-pin Hirose connector. Optional breakout cables are available, and bring each port connection to a panel-mountable DB9-M with an industry compatible RS232 pin-out.


The mPCIe-ICM232 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 surroundings containing industrial machinery and inductive loads. These applications include factory automation, energy management, industrial ON/OFF control, security systems, manufacturing test, and process monitoring. Careful attention has been paid to isolation design, including extensive keep-out zones and hand-routed circuit paths, as well as component and material selection. The mPCIe-ICM232 Series can be used in the following markets.

  • Health and Medical Systems
  • Point of Sale (POS)
  • Automated Retail Kiosks
  • Embedded Systems
  • Traffic Systems
  • Factory Automation and Process Control
  • Retail
  • Hospitality
  • Gaming
  • Kiosks


Our Tru-Iso™ products are designed under IPC-2221B Generic Standard on Printed Board Design. The circuit is isolated with a ≥ 300mil gap between all signal and plane layers between the ports and the PC, and a ≥ 100mil gap port to port. These gaps are rated under IPC-2221B at a peak working voltage of 1500V (Port to PC) and 500V (Port to Port). Our circuit uses a chip-level high-frequency DC-DC isolator which is rated at 2500V rms for 1 minute under UL 1577 optical isolators standard. This isolation component has an over 50 year isolation lifespan even if the isolation voltage potential is in excess of 350 volts AC. Tru-Iso products are also designed to meet EN60601 medical electrical equipment standard. TRU-ISO™, for true signal isolation.

Special Order

Please contact ACCES with your precise requirement. Examples of special orders would be custom oscillators, conformal coating, custom software or product labeling, and more. We will work with you to provide exactly what is required.

Accessories and Connections

Available accessories include 4 or 2-port DB-9 cable kits and screw terminal board for quick and easy connectivity. The ADAP9 accessory provides a screw terminal connection to break out the RS232 signals on the DB9M connector. I/O is accessed via Hirose DF57 5-pin latching connectors on the card.


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. Additional drivers may be available for a wide variety of operating systems including Windows CE, WES7+, vxWorks, and more. Please contact the factory for compatibility with your specific OS.


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.

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.

DF57 Pinout
PinSignal NamesSignal Descriptions
1GNDSignal Ground
2TXTransmit Data
3RXReceive Data
4RTSRequest To Send
5CTSClear To Send
DB-9 Male Pinout
PinSignal NamesSignal Descriptions
1ncno connect
2RXReceive Data
3TXTransmit Data
4RTSRequest To Send
5GNDSignal Ground
6ncno connect
7RTSRequest To Send
8CTSClear To Send
9ncno connect

PC Interface

  • PCI Express Mini Card: Type F1 "Full Length" V1.2

Communications Interface

  • Connector
    • I/O: Hirose DF57 5-pin, latching
    • Mating: Hirose DF57H-5S-1.2C
  • Serial Ports: 4 (or 2) RS-232
  • UART: Quad 16C950 with 128-byte FIFO for each transmit & receive buffer
  • Baud Rates: Up to 921.6k baud (advanced-prescaler allows a wide variety of unusual baud rates to be achieved)
  • Character length: 5, 6, 7, 8 bits (contact factory for assistance with 9-bit data)
  • Parity: Even, Odd, None, Mark, Space
  • Stop Interval: 1, 1½, 2 bits
  • Flow Control: RTS/CTS, Xon/Xoff, None


  • Operating Temperature: -40°C to 85°C
  • Storage Temperature: -65°C to 150°C
  • Humidity: 5% to 95%, non-condensing
  • Power required: +3.3VDC @ 1.8W (typical)
  • ESD Protection: ±15kV on all signal pins (IEC 61000)


  • Weight:8 grams
  • Size: length: 50.95mm (2.006″); width: 30.00mm (1.181″)

The 4-port model violates component height restriction on ″bottom″ side by up to 1.3mm. Confirm your host PC does not place components under the mPCIe footprint before ordering.

Isolation: Tru-Iso™

  • UL1577
    • 2500V rms for 1 minute
  • IPC-221B
    • Port-to-PC: 1500V peak (AC or DC)
    • Port-to-port: 500V peak (AC or DC)
  • Careful attention has been paid to isolation design, including extensive keep-out zones and hand-routed circuit paths, as well as component and material selection.

Regulatory Compliance

  • This product is designed to be in full compliance with CE requirements.

OEM and volume pricing available, please call us.  

ModelPrice (USD)

mPCIe-ICM232-44-port isolated RS-232 PCI Express Mini Card with industrial operating temperature
mPCIe-ICM232-22-port isolated RS-232 PCI Express Mini Card with industrial operating temperature
CAB-mPCIe-ICM4Four port DB9 male cable accessory kit $49
CAB-mPCIe-ICM4-IP67Four port DB9 IP67 male cable accessory kit $call
CAB-mPCIe-ICM2Two port DB9 male cable accessory kit $29
CAB-mPCIe-ICM2-IP67Two port DB9 IP67 male cable accessory kit $call
ADAP9Screw terminal adapter (single DB9 female to 9 screw terminals) $19
mPCIe-HDW-KIT22mm mounting hardware kit $1
mPCIe-HDW-KIT2.52.5mm mounting hardware kit $1

Acquisition, Control, Communication: Engineering and Systems