Advantech PCM-3753I, User Manual

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PCM-3753I User Manual 2
Chapter 1 General Information
1.1 Introduction
The PCM-3753I is a 96-ch digital I/O PCI-104 module. The card emu-
lates mode 0 of the 8255 PPI chip, but the buffered circuits offer a higher
driving capability than the 8255. The 96 I/O lines are divided into twelve
8-bit I/O ports: A0, B0, C0, A1, B1, C1, A2, B2, C2, A3, B3 and C3.
Users can configure each port as input or output via software.
Dry Contact Support for Digital Input
Each digital input channel at the PCM-3753I accepts either 0 ~ 5 VDC
wet contact or dry contact inputs. This dry contact capability allows the
channel to respond to changes in external circuitry (e.g., the closing of a
switch in the external circuitry) when no voltage is present in the external
circuit.
Reset Protection Fulfills the True Requirement of Industrial
Applications
When the system is hot reset (the power is not turned off), the PCM-
3753I can either retain the last I/O port settings and outputs value, or
return to its default configuration, depending on the jumper setting. This
function protects the system from wrong operations during unexpected
system resets.