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Availability: Obsolete
OBSOLETE ISA Bus To Header I/O Rack With 6-ft Cable

Production Specification

*** NOTE: This part is obsolete and no longer available when current stock is depleted. ***

: The G4AC5 will no longer be available once current stock is depleted.

The G4AC5 adapter card is used for direct control of Opto 22 I/O units from your PC. Using this card you can access up to 24 points of I/O.

The G4AC5 uses an ISA bus. A 6-foot cable is provided, to connect with a rack that has a header connector.

IMPORTANT: When choosing digital I/O for use with this card, make certain that you choose 5 VDC logic I/O modules. The card is not compatible with 15 VDC or 24 VDC I/O.

Compatible racks and I/O: If you need a cable with an edge connector, see the AC5.

For a similar card using the 33 MHz PCI bus, see the PCI-AC5. For a card using the PCIe bus, see the PCIe-AC5.

For system diagrams and more information, see the PC-Based I/O Control Overview.




AC5 or G4AC5



PCIe (1.x)


I/O points controlled




Computer compatibility

32-bit, 33 MHz PCI 2.1 bus

PCIe 1.1 bus

ISA bus

Power requirements for card (from the PCI or ISA bus on the PC)

Rev C card1: 5 VDC @ 250 mA and 3.3 VDC @ 250 mA

Rev B card*: 5.0 VDC @ 600 mA

12 VDC @ 50 mA and
3.3 VDC @ 500 mA

5 VDC @ 600 mA

Compatible modules

5 VDC logic modules, such as the IDC5, ODC5, G4IDC5, G4ODC5, SNAP-IAC5, etc.2

SDK compatibility

The SDK works with .NET platform languages including C#® and VB.NET®, and supports both 64-bit and 32-bit versions of:

  • o Windows® 10 Professional
  • o Windows 8.1 Professional
  • o Windows 7 Professional

The SDK works with .NET platform languages including C#® and VB.NET®, and supports both 64-bit and 32-bit versions of:

  • o Windows® 10 Professional
  • o Windows 8.1 Professional
  • o Windows 7 Professional


See Note 3.


Jumperless configuration

Jumperless configuration

Seven, used to configure base address





Operating temperature
Storage temperature

0 to 70 °C
-30 to 85 °C

0 to 60 °C
-30 to 85 °C

0 to 70 °C
-30 to 85 °C

Agency certifications





30 months

30 months

30 months

1. Rev C card shows “9278” on the white label; older Rev B card shows a number beginning with “8939”. Rev C card requires both 5.0 and 3.3 volts. This card is not compatible with computers that supply 5 VDC only.

2. Choose 5 VDC logic modules that are compatible with the mounting rack used.
WARNING: Do not use 15 VDC or 24 VDC modules (such as the IDC15 and IDC24). Using these modules with 15 or 24 VDC logic power can cause serious damage to the adapter card and to the computer.

3. The PC-Based Direct I/O SDK no longer supports the AC5 or G4AC5 adapter cards. For these cards, you can continue to use version R5.0b of the PC-Based Direct I/O SDK (PC_Based_Direct _IO_SDK_R5.0b.exe). It can be downloaded from Opto 22's FTP site.

PC-Based I/O Overview

This document shows examples of system architecture for PC-based I/O control systems and lists Opto 22 products that work together for PC-based control. System examples include:

  • Ethernet systems using SoftPAC, a software-based programmable automation controller programmed with PAC Control
  • Ethernet systems using the OptoMMP protocol
  • Direct control of I/O using no I/O processor (no brain)
  • High-speed control using the Pamux protocol
NOTE: Before choosing to use a PC for control, consider groov EPIC.  A groov EPIC processor offers many features similar to a PC, such as a Linux OS with optional secure shell access; cybersecurity features; Ethernet, USB, and HDMI ports; and the ability to run the control program and HMI on the same hardware. In addition, a groov EPIC system offers real-time control using traditional programming languages; guaranteed-for-life I/O on the same chassis; industrial toughness for hazardous locations; and easier integration with company computer networks, manufacturing, business, and facility systems, and cloud-based services & software.

PCI-AC5, PCIe-AC5, AC5, and G4AC5 Adapter Cards Data Sheet

The PCI-AC5, PCIe-AC5, AC5, and G4AC5 adapter cards provide a PC interface for Opto 22 digital I/O mounting racks.

PCI-AC5, PCIe-AC5, and AC5 User's Guide

Opto 22 PCI-AC5, PCIe-AC5, and AC5 (or G4AC5) adapter cards provide an interface between personal computers and Opto 22 digital input/output (I/O) mounting racks for direct connection to I/O points.

This document includes installation and use instructions for the cards and the driver toolkit that comes with them.

No downloads are available for this product.
No videos or demos are available for this product.