Measurement Specialties PCI-QUAD-AC5 - Manual (Page 8)

Chapter 1
Introducing the PCI-QUAD-AC5
Overview: PCI-QUAD-AC5 features
The PCI-QUAD-AC5 is a 96-bit, high output, digital I/O board for PCI-compatible computers. Primarily
designed as a direct interface to the industry-standard SSR-PB24 rack, the board is also highly useful as a
general purpose digital I/O board.
The 96-bits of digital I/O are organized into four 24-bit groups based on an 82C55 mode 0 emulation (no
strobed I/O or bi-directional I/O bits). Each 24-bit group is divided into three eight-bit ports labeled
PORTA, PORTB and PORTC. PORTC can be split into two four-bit nibbles — Port C-HI and Port C-
LO. Each of these ports may be individually programmed as input or output.
All inputs and outputs are TTL compatible. The digital output drivers are 74S244 chips that can sink
64 mA and source 15 mA. The input buffers are 74LS373 chips and have standard high input impedance
of the 74LS series devices. All I/O is brought out to a 50-pin connectors, which also allows connection to
the PC’s +5 Volt and Ground.
On power up and reset, all I/O bits are set to input mode. If you are using the board to control items that
must be OFF on reset, install pull-down resistors. Each board is equipped with open locations where you
can install SIP resistor networks for either pull-up or pull-down.
The PCI-QUAD-AC5 board is completely plug-and-play, with no jumpers or switches to set. All board
addresses and interrupt sources are set by the board's plug-and-play software. Board configuration is
controlled by your system's BIOS.
Software features
The following software ships with the PCI-QUAD-AC5 free of charge.
ƒ InstaCal installation, calibration, and test utility
ƒ TracerDAQ™ suite of virtual instruments
ƒ SoftWIRE® for Visual Studio® .NET graphical programming
ƒ MCC DAQ Components for VS .NET (installed with SoftWIRE® for VS .NET)
For information on the features of InstaCal, TracerDAQ, and SoftWIRE, refer to the Quick Start Guide
booklet that shipped with the PCI-QUAD-AC5.
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