Manual PCIe-DIO-120/96/72
5
Chapter 1: Introduction
The PCIe-DIO-120 series are x1 lane PCI Express (PCIe) boards with 120, 96, or 72
digital I/O lines designed for use in a variety of Digital I/O (DIO) applications. They use
the high speed PCIe bus to transfer digital data to and from the board. The FPGA based
DIO emulates 8255 compatible chips in mode 0, making it easy to program. This also
allows for simple migration from older ACCES’ PCI-based DIO boards. Lastly, the x1
lane PCIe connector is very flexible and can be inserted into any x1, x4, x8, x16, or x32
PCIe slot.
Features
• 72, 96 and 120 channels of digital input/output
• IRQ generation from Port C bit 3
• All I/O lines are buffered on the card
• Four and eight bit ports independently selectable for I/O on each 24-bit group
• Jumper configurable pull-up / pull-down 10kΩ resistors on I/O lines
• Fused VCCIO supply available to user on each 50 pin header
• I/O ports globally tri-stateable through software
• Compatible with industry standard I/O racks like Grayhill, Opto 22, Western Reserve
Controls, etc.
Applications
• Automatic Test Systems
• Security Systems, Energy Management
• Robotics
• Relay Monitoring and Control
• Parallel Data Transfer to PC
• Sensing switch closures or TTL, DTL, CMOS Logic
• Driving Indicator Lights or Recorders
Functional Description
This manual applies to Models 120, 96, and 72. The same circuit board is used for all
three models. The board is populated for 120 bits, 96 bits, and 72 bits respectively.
Buffers
Each I/O line is buffered and capable of sourcing or sinking 32mA when VCCIO is
configured for 5V. The board contains FPGA circuitry that emulates type 8255 mode 0
Programmable Peripheral Interface (GROUP) to provide a computer interface to digital
I/O lines. Each group supports two 8-bit ports (A, B) and two 4-bit ports (CHi, CLo). Each
port can be configured to function as either input or output latches. The I/O line buffers
are configured automatically by hardware logic for input or output according to the
GROUP Control Register direction software assignment. All DIO lines can be tristated as
well using the corresponding software command.
