Introducing the pci-dual-ac5, Overview: pci-dual-ac5 features, Software features – Measurement Computing PCI-DUAL-AC5 User Manual
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Chapter 1
Introducing the PCI-DUAL-AC5
Overview: PCI-DUAL-AC5 features
The PCI-DUAL-AC5 is a 48-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 48-bits of digital I/O are organized into two 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 100-pin connector, 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-DUAL-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
For information on the features of InstaCal and the other software included with your PCI-DUAL-AC5, refer to
the Quick Start Guide that shipped with your device. The Quick Start Guide is also available in PDF at
Check
for the latest software version or versions of the software supported
under less commonly used operating systems.