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PC/104 Analog Output Board


Analog Output:

  • 4 channels, 12 bit resolution
  • Selectable unipolar or bipolar ranges 0-5V, 0-10V, ±5V, ±10V
  • 100K conversions per second
  • 3mA drive

Digital Input/Output:

  • 24 parallel bits (two 8 bit ports, two 4 bit ports)
  • 64mA sink, 32mA source (ports A and B)
  • I/O pulled up to 5V
  • Change of state detect on port C
  • Type 82C55 PPI mode 0 (1 and 2 optional)
  • Industry Standard 50 pin header

Timer/Counter: Type 82C54 (3x16 bit)

  • Software Supported Modes:
    • Three 16-Bit type 82C54
    • Event counter, Frequency output
    • Frequency and Pulse measurement

I/O Connectors:

  • Two Industry Standard 50 pin headers
  • Designed, made, supported, and manufactured in the USA

  • RoHS Available. Please contact us for ordering information

    The following functions are available in many configurations giving the user the ability to specify exactly what’s needed. Interrupts are individually or globally enabled or disabled via software. A status register is provided to determine the interrupt source.


    Output ranges of 0-5V, 0-10V, ±5V and ±10V, are field selectable with jumpers. Note that four conversions may take place at once and that, since the D/As are double buffered, data for the next conversion may be loaded simultaneously.


    The circuit uses an 82C54 (3 sixteen bit counter/timers). The user has access to each counter/timer’s gate, clock, and output signals. The output of counter two can be used to generate an interrupt. The software package supports counting events, frequency output, pulse and frequency measurement.


    The circuit uses an 82C55A PPI with mode 0 supported. Ports A and B (16 lines) are buffered and pulled up to 5V. Port C features Change of State detection.


    The package includes a setup program detailing all jumper settings. Also included are IRQ drivers, samples for DOS, and utilities for Windows operating systems (XP -> 10, both 32 & 64 bit). Full register-level support for use in custom real-time or embedded operating systems.

    Available Reference Manuals

    Available Software Downloads

    Available Datasheets

    Drivers and Downloads

    Full list of available Downloads: Software Packages, Drivers, Manuals, and other documents

    Information about our Free Software packages:

    ACCES is proud to provide a full suite of software support with every Data Acquisition product. We are committed to supporting the most popular operating systems and platforms for our customers. Currently we are actively supporting Windows XP through Windows 10, including "Server 2008," "Embedded," and "Compact" flavors in both 32-bit and 64-bit for all plug-and-play products including PCI, PCI Express, USB, and more. Many products continue to ship with support for additional operating systems such as DOS, Windows 95, 98, Me, NT4, and 2000.


    Among the software we deliver with our products are sample programs in a wide variety of programming languages. These samples are used to demonstrate the software interfaces to our products — and many can be used as-is in your production environments, or to test functionality of the devices out-of-the-box. We're currently actively supporting sample programs in Visual C# and Delphi with many devices including samples in Visual Basic and Visual C/C++, as well as Borland C/C++ 3.1 for DOS. Additionally we provide National Instruments LabVIEW compatible DLLs and demonstration VIs for many of our devices.


    Drivers for various operating systems are also provided, including active support for Windows XP -> 10 — all in both 32-bit and 64-bit flavors, and including consumer, server, and embedded varieties — as well as the Linux kernels 2.6 and newer and recent macOS versions. Many products continue to ship with driver support for Windows 95, 98, Me, NT4, and Windows 2000, but support for these operating systems is considered deprecated.

    Setup Programs and Utilites

    Our Data Acquisition devices also include a graphical setup utility that walks you through the process of configuring any option jumpers or switches on the device, as well as explaining a little about the various connectors present.

    Many devices also include utility programs - little tools to make your use of the device easier, such as WinRISC, a "Really Incredibly Simple Communications" terminal program that lets you get started instantly with serial devices.

    "Register Level" Documentation

    Besides all this software in all these languages and operating systems ACCES has a policy of open and transparent development: none of our lowest-level "register" interfaces are hidden from you — we document every register in every bus card, every command in every serial board, and every usb control transfer in every USB Data Acquisition board. These lowest-level interfaces allow you to develop for our products in ANY operating system or language, regardless of our actively supporting it or having a driver for it. We have customers actively developing in ADA, Android, Python, Java, MATLAB, Solaris, and more, just by referring to our complete low-level interface documentation! And we provide the full source code to all of our drivers, regardless of operating system, to give you an even bigger head start in your own development tasks.

    No Fees or Royalties

    All of this software is provided at no additional charge, and is licensed under any of a variety of flexible — and royalty free — options. Check out our software license explanation if you'd like more information.

    non-plug-and-play driver install guide for Windows

    Please refer to the Non-PnP Install Guide for instructions to get your PC/104 and ISA bus devices installed in modern Windows.

    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.


    Analog Outputs

    • Channels: 4
    • Voltage Ranges: 0-5V, 0-10V, ±5V, ±10V
    • Conversion Frequency: 100K Conversions per second
    • Resolution 12-Bit
    • Output Drive Capability: 3 mA per channel
    • Power-Down Mode Current Draw: 1µA, maximum
    • Relative Accuracy: ±2 LSB, typical
    • Trigger Source(s): Software selectable for program command or programmable timer

    Digital Inputs/Outputs

    • Programmable Peripheral Int.: 82C55A
    • Channels: 24, pulled up to 5V via 10K (or pulled down to ground)
    • Buffered Channels: 16 (ports A & B)
    • Sink & Source Current: 64mA & 32mA respectively
    • Modes supported: Mode 0 (1 and 2 are factory options)
    • Change of State Detection 8 inputs (port C)


    • Peripheral Interface Timer: Type 82C54
    • Counters 3 x 16-Bit down counters
    • Clock Frequency Output: 1Mhz
    • Inputs/Outputs Fully Buffered
    • Native Modes: Pulse on terminal count, retriggerable one-shot, rate generator, square wave, software triggered strobe, hardware triggered strobe.
    • Software Support: Event Counter, Frequency Output, Frequency and Pulse Measurement


    • Power Required: +5V @ 40mA, ±12 @ 30mA; with optional ±12V DC/DC conv. +5V @ 240mA
    • Environmental: 0°C to +70°C standard, optional without DC/DC converter -40°C to +85°C
    • Interrupt Requests: Eleven channels, IRQ 3-7, 9-12, 14, 15
    • Interrupt Status Register: Indicates source(s) of interrupt
    • Interrupt Enable/Disable: Software Controlled

    CE testing & approval must be done at the system level, in the designed enclosure, and is not done on individual boards.

    ModelPrice (USD)

    Acquisition, Control, Communication: Engineering and Systems