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PCIe-DIO-24HS and PCIe-DIO-24H

PCI Express Digital I/O Cards with Change-of-State (COS) Detection


  • 24 high-current DIO lines
  • IRQ generation from Port C bit 3, and Counter A2 ("C" models) and/or Change-of-State (COS) Detection ("S" models)
  • DIO lines buffered
  • Four and eight bit ports independently selectable for inputs or outputs
  • User configurable 10k ohm Pull-up/Pull-down resistors on DIO lines
  • Jumper selectable VCCIO (5V, 3.3V)
  • VCCIO voltage available to the user via 0.5A resettable fuse
  • Latching 50 pin connector
  • Designed, made, supported, and manufactured in the USA


  • Extended temperature operation (-40° to +85°C)
  • Quick-disconnect tab on mounting bracket for wiring harness or cable shield ground (with non-latching 50 pin connector)
  • RoHS compliant version
  • Support for Wind River VxWorks (call for ordering information)

This product is a x1 lane PCI Express digital I/O board available in two models. The PCIe-DIO-24H is the basic DIO and the PCI-DIO-24HS features advanced change-of-state (COS) detection capabilities. The card emulates an 8255 compatible chip, providing 24 DIO lines. The DIO lines are grouped into three 8-bit ports: A, B, and C. Each 8-bit port is configured via software to function as either inputs or outputs. Port C can be further broken into two 4-bit nybbles via software and configured as either inputs or outputs.

Each DIO line is buffered and capable of up to 32mA source/sink. The VCCIO logic level is globally configured via jumper selection as 5V or 3.3V. Also, ports A, B, C low nybble, and C high nybble are individually jumper configured as pull-up or pull-down through 10kΩ resistor networks.

The card is half-length with a 4.2 inch seated height. I/O wiring connections for this board are via a male 50 pin right angle connector on the card mounting bracket. A ribbon cable can be used to connect this card to termination panels.


Available accessories include a broad range of ribbon cables, screw terminal boards and optically isolated adapters and DIN-rail mounts for a variety of quick and easy connectivity options. Use ribbon cables with a female header on one end and a 50-pin female edge connector on the other to connect with industry standard solid state module racks.


The card is supported for use in most operating systems and includes a free DOS, Linux, and Windows XP -> 10, both 32 & 64 bit compatible software package. This package contains sample programs and source code in Visual Basic, Delphi, and Visual C++ for Windows. Also provided is a graphical setup program in Windows. Linux support includes installation files and basic samples for programming from user level via an open source kernel driver. Third party support includes a Windows standard DLL interface usable from the most popular application programs. Embedded OS support includes Windows Xpe, WES7, vxWorks, etc.

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 DAQ cards to VxWorks 7!

VxWorks 7 VxBus Gen 2 drivers, with easy-to-use API-libraries, are available for this product, including full source and sample code.

Designed to be compatible with our AIOWDM.dll Windows driver & API, this kernel module adds zero% CPU-cycle overhead to your VxWorks runtimes while allowing the lowest-latency hardware register access possible.

You can find more information about our VxWorks libraries and services on our Wind River Silver Partner page.

Digital I/O

  • Lines: 24; Ports A, B, and C
  • Type: Emulates 8255 compatible chips
  • Logic Level: VCCIO
  • Pull-up/down: 10k ohm, jumper selectable

Logic Levels

  • 5 Volt
    • Input Low ≤ 1.5V, ≤2µA
    • Input High ≥3.5V, ≤2µA
    • Output Low ≤ 0.55V @ 32mA
    • Output High ≥3.8V @ 32mA
  • 3.3V
    • Input Low ≤ 0.8V, ≤2µA
    • Input High ≥2.0V, ≤2µA
    • Output Low ≤ 0.55V @ 24mA
    • Output High ≥2.4V @ 24mA


Operating Temperature: 0°C to 70°C, optional -40° to +85°C
Storage Temperature: -55°C to +150°C
Humidity: 5% to 95% RH, w/o condensation
Card Dimensions: Half-Length; Height - 4.2" seated

Regulatory Compliance

  • This product is in full compliance with CE requirements.

OEM and volume pricing available, please call us.  

ModelPrice (USD)

Ordering Guide
PCIe-DIO-24HPCI Express 24 channel digital I/O card
PCIe-DIO-24HSPCI Express 24 channel digital I/O card with change of state detection (COS)
UTBK-50Direct connect 50-pin removable screw terminal board $49
STB-50DIN-rail mountable screw terminal board for 37-pin connector $39
CAB50F-650 pin ribbon cable with female header connectors, 6 feet long $30
IIB-2424 channel optical isolater board for each 50 pin header $149
ROB-2424 channel electromechanical relay card for each 50 pin header
A24A24 channel mounting card for solid state I/O modules, 50 pin edge connector $149
CAB50-6Ribbon cable with 50-pin female edge connector on one end and 50-pin female connector on the other end $30
ROB-8A8 channel electromechanical relay card for each 50 pin header
STA-50Screw terminal board for 50-pin connector $79
T-BOXSteel enclosure with powder coated finish, use to mount STB-50 to panel $45
Model Options (call for pricing)
-RoHSRoHS compliant version
-TExtended temperature (-40°C to +85°C)
-S03Non-latching 50 pin header and mounting bracket with ground tab

If you don't see what you need, ask us and we will make it for you.

Acquisition, Control, Communication: Engineering and Systems