104-DIO-48E and 104-DIO-24E

Digital I/O Cards


  • 48 Parallel Bits of Digital I/O Type 82C55 PPI mode 0
  • Compatible with Opto-22 type Solid State Module Racks
  • Two 24 bit groups (two 8 bit ports, two 4 bit ports each group)
  • All bits are buffered, 64mA sink, 32m A source
  • I/O pulled up to 5V for Contact Monitoring, Pulldown resistors are an option (factory installation)
  • Fused (resetable) 5V available on pin 49 of each group
  • I/O connectors: Two Industry Standard 50 pin headers plus one ten-pin header for counter timer

Factory Options: (call for pricing and availability)

  • 82C54 with three 16-bit counter/timers for event counting, frequency output, pulse width and frequency measurement
  • 0 to 70C and -40 to +85C versions available
  • Pull-down resistors on I/O lines
  • RoHS Available. Please contact us for ordering information

The circuits use an 82C55A PPI with mode 0 supported. Ports A, B and C are buffered with 74ABT245 transceivers and pulled up to 5V.

The optional 82C54 has three-sixteen bit down-counters within one chip. These counters are useful for making frequency outputs, measuring frequency of square waves, pulse width outputs, pulse width measurements etc. Software drivers are provided on CD.

Drivers and Downloads

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.

Available Reference Manuals

Available Software Downloads

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.


Software Support

  • DOS, Linux, Windows XP -> 10, both 32 & 64 bit Sample Programs and Drivers
  • Event Counter, Frequency Output, Frequency and Pulse Measurement


  • Power Required: +5V @50mA Typical
  • Operating Temperature: 0°C to +70°C, optionally -40°C to +85°C available
  • Storage Temperature: -40 to +150°C
  • Interrupt Requests: Eleven channels, IRQ 3-7, 9-12, 14, 15

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

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