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P104-DIO-96 Series

PC/104-Plus or PCI-104 48 and 96-Channel Digital I/O with Change-of-State


  • PC/104-Plus (PCI-104 Optional)
  • 48 or 96 Channel TTL-DTL high speed digital I/O
  • Software selectable in vs. out as 8 bit and 4 bit ports
  • Emulates 4 industry standard 8255 PPIs (mode 0)
  • Full 32-bit PCI interface design
  • Buffered circuits for higher driving capacity
  • Low CPU overhead
  • Known power-up states
  • Output port status read back
  • Standard 50-pin IDC connectors (x4)
  • 0 to +70° C and -40 to +85° C versions available
  • RoHS Available. Please contact us for ordering information
  • Designed, made, supported, and manufactured in the USA
Each I/O line of this card is buffered and capable of sourcing 32mA, or sinking 64mA. The board simulates Programmable Peripheral Interface chips (PPI) to provide a computer interface to digital I/O lines. Each PPI supports two 8-bit ports (A, B) and two 4-bit ports (Chi, Clow). Each port can be configured to function as either input or output latches. The I/O line buffers (types 74ABT240 and 74ABT245) are configured automatically by hardware logic for input or output according to the PPI Control Register direction software assignment.

Outputs of the I/O buffers are pulled up through 10KO resistors to +5VDC.

I/O wiring connections are via 50-pin headers on the board. This provides compatibility with OPTO-22, Gordos, Potter & Brumfield, Western Reserve Controls, etc. module mounting racks. Every second conductor of the flat cables is grounded to minimize crosstalk between signals. If needed for external circuits, +5VDC power is available on each I/O connector at pin 49. If you use this power, we recommend that you include a 1A fast blow fuse in your circuits in order to avoid possible damage to the host computer.

The card occupies 32 addresses within the PCI I/O space. The base address is assigned by the system. Refer to the Option Selection Section of this manual for a detailed description.

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.



Data Transfer Rate, I/O Mapped

  • I/O connector to/from PCI bus: 7.37M bytes per second

Digital Inputs (TTL Compatible)

  • Logic High: 2.0 to 5.0 VDC
  • Logic Low: -0.5 to +0.8 VDC
  • Input Load (High): 10µA
  • Input Load (Low): -10µA

Digital Outputs

  • Logic High: 2.5 VDC min., source 32 mA
  • Logic Low: 0.5 VDC max., sink 64 mA
  • Power Output: +5 VDC from computer bus (onboard resettable 0.5A fuse) on each digital group's I/O connector
  • Power Required: 290 mA typical at 5V (all I/O pins disconnected, all I/O ports set as inputs)


  • Operating Temperature: -20°C to +70°C
  • Humidity: 0 to 90% RH, non-condensing
  • Storage Temperature: -50°C to +120°C

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