Access PCI-DIO-24D(H) User Manual

  

 

 

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24 Bits of Digital Input/Output. 

 

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All 24 I/O Lines Buffered on the Card. 

 

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I/O Buffers Can Be Tri-stated under Program Control. 

 

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Four and Eight Bit Ports Independently Selectable for I/O. 

 

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Pull-Ups on I/O Lines. Pull Down resistors may be installed at the factory (**per port 8 bit**) 

 

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Resettable fused +5V Supply Available to the User. 

 

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"H" version compatible with Industry Standard I/O Racks. 

 

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Three optional i8254 type (**9 16-bit converters**) counters. 

  

 

 

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Automatic Test Systems. 

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Laboratory 

Automation. 

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Robotics. 

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Machine 

Control. 

 

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Security Systems, Energy Management.  

 

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Relay Monitoring and Control. 

 

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Parallel Data Transfer to PC. 

 

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Sensing Switch Closures or TTL, DTL, CMOS Logic. 

 

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Driving Indicator Lights or Recorders. 

 

  
The card comes in two basic models. The difference between the two models is that I/O connections to 
the D are via a standard 37-pin D-sub connector while I/O connections to the H are via a 50-pin 
connector. The cards are 4.8 inches long and may be installed in any 5V PCI-bus slot in IBM and 
compatible personal computers. 
  
These cards provide 24 bits of parallel digital input/output on the PCI bus. These cards contain a type 
8255-5 Programmable Peripheral Interface (PPI) chip. They can be programmed to accept inputs or to 
provide outputs on three 8-bit ports designated Ports A, B, and C. Port C can be further divided into two 
4-bit nibbles. The direction of each port is independent of other ports. 
  
Also, bit 3 of Port C can be used as an internal interrupt to the computer if the Interrupt Select 0 jumper is 
installed in the INT position. On the card, the EXT interrupt position is for factory testing. When bit C3 
goes low (edge triggering) an interrupt is requested.  
  
Each I/O line is buffered by a type 74ABT245B tristate buffer transceiver capable of sourcing 32 mA or 
sinking 64mA. Pull-ups on the card assure that there are no erroneous outputs at power up until the card 
is initialized by system software. The buffers are configured automatically by hardware logic for input or 

Manual PCI-DIO-24DH 

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