Quatech Asynchronous Communications Adapter... User manual

DSC-200/300
Two Channel RS-422/485 Asynchronous
Communications Adapter
for PCI bus
User's Manual
QUATECH, INC. TEL: [phone]
5675 Hudson Industrial Parkway FAX: [phone]
Hudson, Ohio 44236 http://www.quatech.com

WARRANTY INFORMATION
Quatech, Inc. warrants the DSC-200/300 to be free of defects for five(5) years
from the date of purchase. Quatech, Inc. will repair or replace any board that fails to perform
under normal operating conditions and in accordance with the procedures outlined in this
document during the warranty period. Any damage that results from improper installation,
operation, or general misuse voids all warranty rights.
Please complete the following information and retain for your records. Have this
information available when requesting warranty service.
DATE OF PURCHASE:
MODEL NUMBER: DSC-200/300
PRODUCT DESCRIPTION: Two Channel RS-422/485 Asynchronous
PCI Bus Communications Adapter
SERIAL NUMBER:

(c) 1998 - 2000, Quatech, Inc.
NOTICE
The information contained in this document cannot be reproduced in any form
without the written consent of Quatech, Inc. Likewise, any software programs that might
accompany this document can be used only in accordance with any license agreement(s)
between the purchaser and Quatech, Inc. Quatech, Inc. reserves the right to change this
documentation or the product to which it refers at any time and without notice.
The authors have taken due care in the preparation of this document and every
attempt has been made to ensure its accuracy and completeness. In no event will Quatech,
Inc. be liable for damages of any kind, incidental or consequential, in regard to or arising out of
the performance or form of the materials presented in this document or any software
programs that might accompany this document.
Quatech, Inc. encourages feedback about this document. Please send any written
comments to the Technical Support department at the address listed on the cover page of this
document.
DOS, Windows ME, Windows 2000, Windows 98, Windows 95, Windows NT are trademarks
or registered trademarks of Microsoft Corporation. OS/2 is a registered trademark of IBM
Corporation. All other trademarks or registered trademarks are property of their respective
owners.

Declaration of Conformity
Manufacturer's Name: Quatech Inc.
Manufacturer's Address: 55675 Hudson Industrial Parkway
Hudson, Ohio 44236 (USA)
Application of Council Directive: 89/336/EEC
Standards to which
Conformity is Declared: * EN50081-1 (EN55022,
EN60555-2, EN60555-3)
* EN50082-1 (IEC 801-2,
IEC 801-3, & IEC 801-4)
Type of Equipment: Information Technology
Equipment
Equipment Class: Commercial, Residential, & Light
Industrial
Product Name: PCI Dual Serial Communications
Card
Model Number : DSC-200/300 (750,IND)

328.5 Half-Duplex/Full-Duplex Selection ......................... 318.4 AUXIN/AUXOUT Loopback ................................ 318.3 XCLK .......................................................... 308.2 RCLK .......................................................... 308.1 RTS/cts Handshake .......................................... 29
8 External Connections .....................................
28
7 OS/2 ............................................................
256.1.1 QTPCI.EXE ................................................. 25
6 DOS and Other Operating Systems ..................
245.6 Windows NT ................................................. 235.5 Using the "New Hardware Found" Wizard ................ 215.4 Windows 95 .................................................. 205.3 Windows 98 ................................................... 195.2 Windows 2000 ................................................ 185.1 Windows Millennium ........................................ 18
5 Windows Configuration .................................
174.4.2 Clock Rate Multiplier ..................................... 164.4.1 Enhanced Serial Adapter Identification ................. 164.4 Options Register .............................................. 154.3 Interrupt Status Register ..................................... 154.2 Enabling the Special Registers .............................. 144.1 Base Address and Interrupt Level (IRQ) ................... 14
4 Address Map and Special Registers .................
13
3 Hardware Installation ....................................
12
2.4.2 Force High-Speed UART Clock (X2, X4, or X8,
J10-J12) ...........................................................
112.4.1 Enable Scratchpad Register (SPAD, J13) ................. 112.4 Clock Rate and Optional Registers .......................... 102.3 Full-duplex/Half-duplex Operation ........................ 102.2 Signal Connections ........................................... 92.1 RS-422 or RS-485 Signal Line Termination .................. 9
2 Hardware Configuration .................................
81.1.1 "IND" Option --- Surge Suppression Upgrade ........... 81.1 Features ........................................................ 7
1 General Information ........................................

38
11 Troubleshooting .........................................
37
10 Specifications ..............................................
36
9 PCI Resource Map ..........................................
358.7 RS-422/485 Peripheral Connection .......................... 348.6 Termination Resistors ........................................

1General Information
The Quatech, Inc. DSC-200/300 provides two RS-422 or RS-485 asynchronous
serial communication interfaces for IBM-compatible personal computer systems using
the PCI expansion bus. The DSC-200/300 uses Quatech's new Enhanced Serial Adapter
design. Legacy serial port data rates are limited to a maximum of 115,200 bits per
second. Quatech Enhanced Serial Adapters can achieve data rates as high as 921,600
bits per second.
As a PCI device, the DSC-200/300 requires no hardware configuration. The card
is automatically configured by the computer's BIOS or operating system. The two
serial ports share a single interrupt line and are addressed in a contiguous block of 16
bytes. Aspecial interrupt status register is provided to help software to manage the
shared interrupt.
The DSC-200/300's serial ports are using 16750 Universal Asynchronous
Receiver/Transmitters (UARTs). These UARTs contain hardware buffers (FIFOs) which
reduce processing overhead and allow higher data rates to be achieved. The 16750
contains a 64-byte FIFO and can transmit and receive data at a rate of up to 921,600 bits
per second. The 16750 is recommended for heavy multitasking environments and for
applications involving high data rates.
The DSC-200/300 is supported under several popular operating systems and
environments. Contact the sales department for details on current software offerings.
Most device drivers are available for download from the Quatech world wide web site
at http://www.quatech.com.
Quatech DSC
-200/300 User
'
s Manual
7

1.1Features
The standard DSC-200/300 implements each of its communication channels with
a 16750 UART and uses standard line driver and receiver components. For improved
performance and industrial-grade reliability.
1.1.1"IND"Option --- Surge Suppression Upgrade
The "IND"upgrade provides the protection essential for reliable use in an
industrial environment. Each communication line has a surge suppressor capable of
sustaining up to 40A20us peak transient surges, a clamping voltage of 30V and a peak
energy dissipation of 0.1 Joules.
Quatech DSC
-200/300 User
'
s Manual
8

2Hardware Configuration
The DSC-200/300 is automatically configured at boot time by the computer's
BIOS or operating system. There are no required switches or jumpers to set for
installation.
This chapter lists a number of jumper settings that control various hardware
features. Jumpers J1-J4, located in a column near the D-9 connectors, control the RS-422
or RS-485 signal line termination. Jumpers J5-J8, located in a column just to the right of
J1-J4, control how signals are routed from the UARTs to the connector, as well as full- or
half- duplex operation. Jumpers J10-J13, grouped together at the end of the board
opposite the D-9connectors, control special options.
Any changes from the factory default should be made before installing the
DSC-200/300 in the computer.
2.1RS-422 or RS-485 Signal Line Termination
Jumpers J1-J4 allow the selection of 100-ohm RS-422 termination, 120-ohm RS-485
termination, or no termination at all. The factory default, shown in Figure 1, is RS-422
termination. For full details, see page 24.
1
2
3
RS-422 termination
(100 ohms)
(factory default)
Jumpers J1-J4
Figure 1--- Factory default signal termination settings
Quatech DSC
-200/300 User
'
s Manual
9

2.2Signal Connections
The DSC-200/300 provides each of two serial ports with four differential signal
pairs: TxD, RxD, AUXOUT, and AUXIN. TxD and RxD are always present at the
connector. The AUXOUT and AUXIN signals can be used to support RTS/CTS
handshaking, external clocking, or external signal loopback. The factory default
configuration, as shown in Figure 2, is a loopback of AUXOUT to AUXIN at the
connector, with RTS and CTS looped back on the board. There is an extensive
discussion of this topic starting on page 19.
2.3Full-duplex/Half-duplex Operation
The DTR or RTS modem control output of the UART can be used to enable and
disable the transmit drivers. The inverse of these signals can also be used to enable
and disable the receivers. These options are selectable per channel. The factory
default, as shown in Figure 2, is for both the drivers and receivers of both channels to
be continuously enabled. Two spare jumpers are installed in neutral positions. For
details, refer to page 22.
The DSC-200/300 is shipped from the factory with each channel configured as
shown in Figure 2.
Loopback RTS to CTS
Loopback AUXOUT to AUXIN
Loopback XCLK to RCLK
CTS
AUXIN
XCLK
RTS
AUXOUT
RCLK
1
2
36
5
4
Full Duplex Operation
1
2
3
6
5
4
RTS
DTR
Tx ENABLE
Tx ENABLE
Tx ENABLE Rx ENABLE
(spare jumpers supplied)
JumpersJ5,J7
JumpersJ6,J8
Figure 2--- Factory default signal interface settings
Quatech DSC
-200/300 User
'
s Manual
10