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

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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 70°C and -40 to 85°C versions available
    • Pull-down resistors on I/O lines

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.




Software Support

  • DOS, Linux, Windows 95/98/Me/NT4/2000/XP/2003 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.
Part Number Price(USD)
View / Download Manual (in .pdf format)
Acquisition Control Communications Engineering / Systems
USA Office

Address: 1480 Gulf Road, Suite 837,
PO Box 1364
Point Roberts, WA 98281

Western Canada - Vancouver BC

Tel:1.800.663.6001 or 1.604.925.6150
Address: 2454 Haywood Ave
West Vancouver, BC V7V 1Y1

Eastern Canada - Markham, Ontario

Tel:1.800.465.0164 or 1.905.513.7027