Advantech PCL-740 User manual

PCL-740
Serial Communication
RS-232/422/485/Current-Loop
Interface Card

Part No. 200074010 2nd Edition
Printed in Taiwan May 2001
Copyright Notice
This documentation and the software included with this product are
copyrighted 2001 by Advantech Co., Ltd. All rights are reserved.
Advantech Co., Ltd. reserves the right to make improvements to the
products described in this manual at any time without notice.
No part of this manual or software may be reproduced, copied,
translated or transmitted, in any form or by any means without the
prior written permission of Advantech Co., Ltd. Information provid-
ed in this manual is intended to be accurate and reliable. However,
Advantech Co., Ltd. assumes no responsibility for its use, nor for any
infringements of rights of third parties which may result from its use.
Acknowledgments
PC-LabCard is a trademark of Advantech Co., Ltd. IBM, PC and
PC/XT/AT are trademarks of International Business Machines
Corporation. MS-DOS, MASM, QuickBASIC, Microsoft C and MS-
PASCAL are trademarks of Microsoft Corporation. Intel is a trade-
mark of Intel Corporation. Turbo C and Turbo PASCAL are trade-
marks of Borland International.

Contents
Chapter 1 Introduction .................................................. 1
Description............................................................................. 2
Features ..........................................................................................3
Applications ...................................................................................3
Specifications.................................................................................4
Chapter 2 Hardware Installation ................................... 7
Initial Inspection ................................................................... 8
PCL-740 Jumper and Switch Locations............................. 9
Card Configuration ............................................................ 10
Jumper settings ................................................................... 12
Card installation ................................................................. 16
Appendix A Register structure and format ............... 17
Register Structure............................................................... 18
Programming example ....................................................... 21
Appendix B PC I/O Address Reference ........................ 25
PC I/O Address Usage......................................................... 26

Chapter 1 Introduction 1
1
Introduction
CHAPTER

2PCL-740 User's Manual
Description
The PCL-740 card enables RS-232, RS-422, RS-485 or current-loop
serial communication for applications in difficult environments. You
can configure its port to RS-232, RS-422, RS-485 or current-loop
using on-board jumpers.
The card features a 16C550 UARTs (with on-chip 16-byte FIFO)
making serial I/O more reliable. By buffering data into 16-byte
packets before putting it on the bus the UART drastically reduces the
CPU load. This makes the PCL-740 especially suitable for high
speed serial I/O applications and applications under MS Windows.
In RS-485 mode, the PCL-740 automatically senses the direction of
incomming data and switches its transmission direction accordingly.
Therefore no handshaking signal (e.g. RTS signal) is necessary. This
feature lets you simply and quickly build an RS-485 network with
just two wires. More importantly, application software previously
written for half duplex RS-232 environments, can be used without
modification.

Chapter 1 Introduction 3
Features
•Serial Port can be configured to RS-232/422/485 or current-loop
•16C550 FIFO UART (with 16-byte FIFO)
•Baud rate up to 115 Kbps
•IRQ selection: 3, 4, 5, 6, 7, 9, 10, 11, 12 or 15
•Complete RS-232 modem-control signals
•Space reserved for optional surge protection (RS-422/485 only)
•Space reserved for termination resistor (RS-422/485 only)
•LED indicator on each port indicates data flow
•Automatic data-flow control in RS-485 mode
Applications
•PLC monitoring and control
•Serial communication in harsh environments
•Data entry terminals
•Remote data acquisition and control
•Instrument controller, distributed control systems
•Interface to modem, bar code reader, scale, plotter
•Multidrop communication networks

4PCL-740 User's Manual
Specifications
Board
•Number of ports: 1
•Protocol selection: RS-232/422/485 or current-loop
•UART: 16C550 (16-byte FIFO)
•I/O address selection: From 200H to 3F8H
•IRQ selection: 3, 4, 5, 6, 7, 9, 10, 11, 12 or 15
•Power consumption: +5 V, 250 mA typical, 350 mA Max.
•Connectors: DB-9 male, DB-25 male
•Operating temperature: 32 to 122oF (0 to 50oC)
•Dimensions: 7.25" x 4.13" (18.4-cm x 10.5-cm)
•Weight: 0.2 Kg
RS-232 interface
•Signal driver/receiver: SN 75188, SN 75189
•Signals: TxD, RxD, RTS, CTS, DTR, DSR, DCD, RI, GND
•Mode: Asynchronous, full duplex
•Baud-rate: 50 to 115200 bps
•Stop bits: 1, 1.5, 2
•Parity: Even, odd or none
•Data bits: 5, 6, 7, 8

Chapter 1 Introduction 5
Current-loop interface
•Signal driver/Receiver: 6N136
•Signals: TxD+, TxD-, RxD+, RxD-
•Current value: 20 mA (Standard)
•Mode: Asynchronous, full duplex
•Baud-rate: 50 to 115200 bps
•Transmission distance: 1000 m
RS-422 Interface
•Signal driver/receiver: SN75176, SN75173
•Signals:
TxD+, TxD-, RxD+, RxD-, RTS+, RTS-, CTS+, CTS-, GND
•Mode: Asynchronous full duplex, point-to-point
•Max data rate: 115 Kbps
•Max data distances: 4000 feet (1220 meters)
RS-485 Interface
•Signal driver/receiver: SN75176
•Signals: DATA+, DATA-, GND
•Mode: Half duplex, multi-drop
•Max data rate: 115 Kbps
•Max data distances: 4000 feet (1220 meters)

6PCL-740 User's Manual

Chapter 2 Hardware Installation 7
2
Hardware
Installation
CHAPTER