Micromod MOD: 1731N ICN Mini-Link Users Guide - Manual (Page 6)

IB-23C003
INTRODUCTION
Physically the Mini Link is a PC/AT plug-in module which completely emulates the 1720N
Communications Link (refer to IB-23C001) for up to two Instrument Communications
Networks. The base configuration consists of:
• An Integral PC/AT Serial Port (dedicated to the Mini Link)
This serial port is DIP switch and jumper configurable to perform as an I/O-mapped
memory device at I/O base addresses 000
h
through 3F8
h
. These addresses include
the memory maps for the standard serial ports COM1, COM2, COM3 and COM4 (see
Section 2.4, Switch and Jumper Settings).
• One Instrument Communications Network Controller
The base ICN Controller is accessed via a two-wire or three-wire connection at the
rear of the personal computer using the three screw terminal block at the connection
marked "ICN0". Communication can be maintained between the personal computer
and up to 15 field instruments.
• Optical Isolation Between Instruments and Personal Computer
The optical isolation feature is jumper-selectable (see Section 2.4, Switch and
Jumper Settings) and provides a minimum of 3000 Vdc electrical insulation between
the Instrument Communications Network and the personal computer. THIS FEATURE
IS NOT FACTORY SET.
• External Pushbutton Reset
A 750ms reset pulse can be issued to the Mini Link by pressing the reset button
located at the rear of the personal computer. The button is prominently labeled
"RESET".
• A Second Serial Port for An External Controlling Device
The Mini Link includes a nine-pin D-Shell connector for an external RS-232 serial port.
This serial port could be used to provide redundant control of the instrument system
with a local or remote external computer.
The 1731N Mini Link Board can be enhanced with a 1732N ICN Interface Board to provide
communications access to an additional 15 field instruments. This daughter board is
mounted to the Mini Link board and is accessed via a two- or three-wire connection at the
rear of the personal computer using the three-screw terminal block at the connection
marked "ICN1".
1.2 EXPLANATION OF SERIAL AND CATALOG NUMBER
The products described in this book have numbers that help identify specific features.
The general format of these numbers is described below. Specific product descriptions
follow in Section 1.3.
The serial number stamped on the product data plate consists of the catalog number and,
in some cases, a sequential identification number. The serial number, which is described
below, contains a series of single and multiple-character codes. These codes provide
specific information concerning various electrical and/or structural options. Certain
combinations are not allowed. Options and combinations are subject to change.
1-2