1 General Information
The Quatech, Inc. DSCLP-200/300 (two-port) and SSCLP-200/300
(one-port) provide RS-422 or RS-485 asynchronous serial communication
interfaces for IBM-compatible personal computer systems using the PCI
expansion bus. For general purposes, this manual usually makes reference only to
the DSCLP-200/300. All information pertains equally to the SSCLP-200/300,
with the exception that with the SSCLP there is just one port instead of two. The
DSCLP-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 DSCLP-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. A special interrupt status register is provided to help software
to manage the shared interrupt.
The DSCLP-200/300's serial ports are implemented using 16550
Universal Asynchronous Receiver/Transmitters (UARTs). These UARTs contain
hardware buffers (FIFOs) which reduce processing overhead and allow higher
data rates to be achieved. The 16550 contains a 16-byte FIFO and can transmit
and receive data at a rate of up to 921,000 bits per second.
The DSCLP-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.
DSCLP/SSCLP-200/300 User's Manual
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