ADLINK Technology PCI-7251 - 1 Introduction

Introduction 1
1 Introduction
The PCI-7250/7251 and cPCI-7252 Relay Actuator and Isolated
D/I cards are basic Digital I/O cards for PCI bus compliant comput-
ers used in industrial applications.
This PCI-7250 and PCI-7251 provides 8 relay actuators and 8
opto-isolated digital inputs. Of the eight relays, four are Form C
(R0~R3) and four are Form A (R4~R7). The cPCI-7252 provides 8
relay actuators and 16 opto-isolated digital inputs; all relays are
Form C. They are very suited for constant ON/OFF control
devices. For convenience the above models will be referred to as
PCI-725X in this manual.
All channels are isolated and suitable for collecting digital input
signals in a noisy environment. For identical non-polarized opto-
isolated digital input channels, switching can be carried out using
AC-filtered or non-AC-filtered channels.
A LED reflects the status of each relay output. When a relay is
energized, its corresponding LED will turn ON, otherwise it is OFF.
The relay outputs and digital inputs are controlled by two bytes of
I/O addresses. When a bit is read or written, its output status will
be controlled, or its input status will be monitored. The I/O signals
are routed through to a 37-pin D-type connector that protrudes
through the computer case at the rear.