Advantech PCI-1751, Руководство пользователя

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PCI-1751 User Manual 2
1.1 Introduction
The PCI-1751 is a 48-bit DI/O and counter/timer card with PCI bus. It provides you
with 48 bits of parallel digital input/output as well as 3 timers. It emulates mode 0 of
the 8255 PPI chip, but the buffered circuits offer a higher driving capability than the
8255.
The card emulates two 8255 PPI chips to provide 48 DI/O bits. The I/O bits are
divided into six 8-bit I/O ports: A0, B0, C0, A1, B1 and C1. You can configure each
port as either input or output via software.
The dual interrupt handling capability provides users the flexibility to generate inter-
rupts to a PC. A pin in the connector can output a digital signal simultaneously with
the card's generating an interrupt. This card uses a high density SCSI 68-pin connec-
tor for easy and reliable connections to field devices.
Two other features give the PCI-1751 practical advantages in an industrial setting.
When the system is hot reset (the power is not turned off) the PCI-1751 retains the
last I/O port settings and output values if the user has set jumper JP4 to enable this
feature. Otherwise, port settings and output values reset to their safe default state, or
to the state determined by other jumper settings. The PCI-1751's other useful feature
is it supports both wet and dry contacts, allowing it to interface with other devices
more easily.
1.1.1 Numbering Convention
All numbers given in this manual are in decimal format unless specifically noted oth-
erwise. In particular, where a register address is given as (Base + 32), the decimal
number "32" should be added to the base value.
1.2 Features

48 TTL level digital I/O lines.

Emulates mode 0 of 8255 PPI

Buffered circuits provide higher driving capability

Interrupt handling

Interrupt output pin for simultaneously triggering external devices with the inter-
rupt

High density SCSI 68-pin connector

Output status readback

Two 16-bit timers can be cascaded to one 32-bit timer, and can generate watch-
dog timer interrupts

One 16-bit event counter can generate event interrupts

Keeps port I/O settings and digital output states after hot system reset

Supports dry contact and wet contact
1.3 Applications

Industrial AC/DC I/O devices monitoring and control

Relay and switch monitoring and control

Parallel data transfer

Sensing the signals of TTL, DTL, CMOS logic

Driving indicator LEDs