DSC-200/300 Two Channel RS-422/485 Asynchronous Communications Adapter for PCI bus User's Manual QUATECH, INC. 5675 Hudson Industrial Parkway Hudson, Ohio 44236 TEL: (330) 655-9000 FAX: (330) 655-9010 http://www.quatech.
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.
(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.
Declaration of Conformity Manufacturer's Name: Manufacturer's Address: Application of Council Directive: Standards to which Conformity is Declared: Quatech Inc.
1 General Information ........................................ 7 1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.1.1 "IND" Option --- Surge Suppression Upgrade . . . . . . . . . . . 8 2 Hardware Configuration ................................. 9 2.1 RS-422 or RS-485 Signal Line Termination . . . . . . . . . . . . . . . . . . 9 2.2 Signal Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.6 Termination Resistors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 8.7 RS-422/485 Peripheral Connection . . . . . . . . . . . . . . . . . . . . . . . . . . 35 9 PCI Resource Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 General 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.
1.1 Features 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.
2 Hardware 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.
2.2 Signal 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.
2.4 Clock Rate and Optional Registers Figure 3 shows the jumper configuration as shipped from the factory, with two spare jumpers applied in neutral positions. Remove one or both and apply as shown in following subsections to set optional features. J10 X2 J11 X4 J12 X8 J13 SPAD Figure 3 --- Factory default clock rate and options settings 2.4.
2.4.2 Force High-Speed UART Clock (X2, X4, or X8, J10-J12) These jumpers force an increase of the UART input clock frequency by a factor of two, four, or eight. This feature can allow legacy software to use baud rates above 115,200 bits per second. It is also useful if the serial port device driver does not directly support setting the higher baud rates through the Options Register (see page 10).
3 Hardware Installation 1. Turn off the power of the computer system in which the DSC-200/300 is to be installed. 2. Remove the system cover according to the instructions provided by the computer manufacturer. 3. Make any desired optional jumper setting changes. 4. Install the DSC-200/300 in any empty PCI expansion slot. The board should be secured by installing the Option Retaining Bracket (ORB) screw. 5. Replace the system cover according to the instructions provided by the computer manufacturer. 6.
4 Address Map and Special Registers This chapter explains how the two UARTs and special registers are addressed, as well as the layout of those registers. This material will be of interest to programmers writing driver software for the DSC-200/300. 4.1 Base Address and Interrupt Level (IRQ) The base address and IRQ used by the DSC-200/300 are determined by the BIOS or operating system. Each serial port uses 8 consecutive I/O locations.
4.2 Enabling the Special Registers The DSC-200/300 contains two unique registers, an Interrupt Status Register and an Options Register. These registers are enabled when the SPAD jumper (J13) is removed (factory default). They replace the UART Scratchpad Register on accesses to register address 7. The Interrupt Status Register and Options Register are accessed through the scratchpad location of any UART. The DLAB bit of the UART (Line Control Register, bit 7) is used to select between the two registers.
4.4 Options Register The Options Register allows software to identify the DSC-200/300 as a Quatech Enhanced Serial Adapter. It also allows software to set the UART clock rate multiplier. Figure 10 shows the structure of the Options Register. The powerup default of the Options Register is all bits zero.
4.4.2 Clock Rate Multiplier A standard serial port operates at a clock speed of 1.8432 MHz. In order to achieve higher data rates, Quatech Enhanced Serial Adapters can operate at two times, four times, or even eight times this standard clock speed. This is controlled by the clock rate multiplier bits in the Options Register. Software can determine the UART clock frequency by reading the clock rate multiplier bits RR1 and RR0 in the Options Register as shown in Figure 12.
5 Windows Configuration 5.1 Windows Millennium 1. After inserting the DSC 200/300 for the first time the "Add New Hardware Wizard" will begin. Select "Search for the best driver for your device.". Check the "Removable media" and "Specify location" box. Click the "Next" button. 3. 4. Window will locate the proper INF file and copy the file from the CD. Click the "Next" button. The final dialog screen will verify the file copy from the CD. Click the "Finish" button.
5.2 Windows 2000 1. After inserting a DSC-200/300 for the first time, the "Add New Hardware Wizard will appear at start up. Click the "OK" button. 2. The following dialog box insert the Quatech COM CD (shipped with the device). Click the "OK" button. 4. The following dialog box will display the appropriate INF file on the CD in drive. Click the "OK" button. 5. Window will copy the INF file from the CD and display a final dialog indication that the process is complete. Click the "Finish" button.
5.3 Windows 98 1. After inserting a DSC-200/300 for the first time, the "Add New Hardware Wizard will appear at start up. Click the "Next" button. 2. Select "Search for the best driver for you device". Click the "Next" button. 3. On the next dialog, select the "CD-ROM DRIVE" check box. Insert the Quatech COM CD (shipped with the device) into the CD-ROM drive. Click the "Next" button.
4. The following dialog box will display the appropriate INF file on the diskette in drive. Click the "Next" button. 5. Window will copy the INF file from the diskette and display a final dialog indication that the process is complete. Click the "Finish" button. 5.4 Windows 95 The following instructions provide step-by-step instructions on viewing resources used by the DSC-200/300 in Windows 95 using the "Device Manager" utility.
4. Double click the DSC-200/300 model name and a properties box should open for the hardware adapter. 5. Click the "Resources" tab located along the top of the properties box to view the resources Windows 95 has allocated for the DSC-200/300 match the hardware configuration. Because PCI is a true plug-and-play bus, do not attempt to modify the configuration values listed. Click "Cancel" to exit without making changes. 6. The DSC-200/300 serial ports are also listed under the group Ports (COM and LPT).
5.5 Using the "New Hardware Found" Wizard The following instructions provide step-by-step instructions on installing the DSC-200/300 in Windows using the "New Hardware Found" wizard. 1. After booting the computer with a newly-installed DSC-200/300, the "New Hardware Found" dialog box will appear. If you have never installed a Quatech PCI communications adapter before, the dialog box may simply indicate that it has found a "PCI Card." 2.
9. The "New Hardware Found" dialog will repeat for each of the serial ports on the DSC-200/300 as each port is registered with Windows. 10. Installation is complete. 5.6 Windows NT The Windows NT device driver is installed by running the SETUP program. Up to 256 serial ports are supported. There is a command line-based configuration utility which is used for adding PCI bus and ISA bus serial ports.
6 DOS and Other Operating Systems The DSC-200/300 is not a direct drop-in replacement for a legacy serial port because its base address and IRQ cannot be fixed at values such as 3F8 hex, IRQ 4 (COM1) or 2F8 hex, IRQ 3 (COM2), etc. Rather, the system BIOS assigns the address and the IRQ in a plug-and-play fashion at boot time. Software which is to use the DSC-200/300 must be able to accommodate any valid assignments of these resources.
The QTPCI program is capable only of displaying the PCI configuration. It cannot be used to make changes. Quatech PCI Configuration Information Display Software Version 1.00 INSTRUCTIONS: -----------------------Press keys listed in the menu at the bottom of the screen. This program only displays information. It cannot make changes. Numbers preceeded by "0x" are hexadecimal. PCI BIOS detected, version 2.
non-Quatech PCI devices in the system, including those devices integrated on the motherboard. In this example, the "Base addr 0" resource is reserved. For users interested in even more details, PCI BIOS information can be displayed by pressing the "B" key. Pressing the "I" key displays the PCI interrupt routing table. Quatech PCI Configuration Information Display Software Version 1.
7 OS/2 The OS/2 device driver supports up to 32 serial ports in a system. Installation is a manual, but simple, process. Please refer to the read me documentation included on the Quatech COM CD with the device driver for full installation and configuration details.
8 External Connections The DSC-200/300 provides four differential communication signals per channel. The two output signals are Transmit Data (TxD) and Auxiliary Output (AUXOUT). The two input signals are Receive Data (RxD) and Auxiliary Input (AUXIN). A ground signal is also provided. The available input signals for AUXIN are Clear To Send (CTS) and the Receive Clock (RCLK). The available output signals for AUXOUT are Request To Send (RTS), the Transmit Clock (XCLK), and the AUXIN signal (for loopback).
8.1 RTS/CTS Handshake Transmission of RTS, combined with reception of CTS, allows for hardware handshaking (data flow control) between the UART and the external device. RTS is transmitted on AUXOUT by connecting pins 4 and 5 of the jumper block. CTS is received on AUXIN by connecting pins 1 and 2 of the jumper block. If RTS/CTS handshaking is not desired, the RTS output can be looped back to the CTS input by connecting pins 1 and 4 of the jumper block. Figure 19 shows how to select the RTS/CTS mode.
8.3 XCLK This is the output clock signal used by the transmitter portion of the UART. It is generally connected to the UART's own receive clock input (RCLK). This is done by connecting pins 3 and 6 of the jumper block. If desired, XCLK can be transmitted to an external source over the AUXOUT line by connecting pins 5 and 6 of the jumper block. Figure 21 shows how to select the XCLK mode.
8.5 Half-Duplex/Full-Duplex Selection Using jumper blocks J6 and J8, the transmitters and receivers of each channel can be enabled and disabled by modem control signals. This allows operation in both half-duplex or full-duplex modes. The transmit drivers can be controlled by either the Data Terminal Ready (DTR) or the Request to Send (RTS) output from the UART. If a jumper is applied between pins 1 and 4, the drivers are enabled for TxD and AUXOUT when the UART's DTR signal is asserted.
Jumpers J6, J8 Tx ENABLE 6 3 Rx ENABLE Tx ENABLE 5 2 RTS Tx ENABLE 4 1 DTR Tx ENABLE 6 3 Rx ENABLE Tx ENABLE 5 2 RTS Tx ENABLE 4 1 DTR Tx ENABLE 6 3 Rx ENABLE Tx ENABLE 5 2 RTS Tx ENABLE 4 1 DTR Half-Duplex(DTR) Operation Half-Duplex(RTS) Operation Full-Duplex Operation Figure 23 --- Half- or full-duplex selection AUXOUT RS-422 or RS-485 Driver + - TXEN XCLK RTS CTS RCLK DTR DSR DCD RI 6 3 5 2 4 1 AUXIN RS-422 or RS-485 Receiver + - RXEN 6 3 5 2 4 1 Figure
8.6 Termination Resistors Line termination resistors are provided for the input signals of each of the DSC-200/300's RS-422/485 ports. Termination may be selected or removed for individual signal lines using jumper blocks J1-J4.
8.7 RS-422/485 Peripheral Connection The DSC-200/300 connects to peripheral equipment through two female D-9 connectors. The serial port connector definitions are listed in Figure 26.
9 PCI Resource Map Listed below are the PCI resources used by the DSC-200/300. Such information may be of use to customers writing their own device drivers or other custom software. A detailed description of the DSC-200/300's UARTs is available on the Quatech web site. (all numbers in hex) PCI Vendor ID: 0x135C Quatech, Inc.
10Specifications Bus interface PCI, 32-bit bus, 5-volt only IBM-compatible computers Dimensions: approx. 5.5" x 3.5" Serial ports Controller: Interface: 16750 with 64-byte FIFOs Two female D-9 connectors Transceivers: Differential output: SP491 or compatible 2V min. with 50-ohm load (RS-422) 1.5V min. with 27-ohm load (RS-485) Output rise/fall time: 3ns min., 40ns max., 15ns typ. Differential input Threshold: -0.2V min., +0.2V max. Input resistance: 12k ohm min., 15k ohm typ. Input current: +/- 1.
11 Troubleshooting Listed here are some common problems and frequent causes of those problems. If the information here does not provide a solution, contact Quatech technical support. Any unauthorized repairs or modifications will void the DSC-200/300's warranty. Computer will not boot up. 1. Is the DSC-200/300 properly inserted? Remove the card and try again. Perhaps try a different expansion slot. 2. Ensure that an ISA-bus card is not using the same IRQ that the PCI BIOS tries to assign to the DSC-200/300.
DSC-200/300 User's Manual Revision 1.