1 General Information
The Quatech, Inc. QSC-100 provides four RS-232 asynchronous serial communication
interfaces for IBM-compatible personal computer systems using the PCI expansion bus. The
QSC-100 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 QSC-100 requires no hardware configuration. The card is
automatically configured by the computer's BIOS or operating system. The four serial ports
share a single interrupt line and are addressed in a contiguous block of 32 bytes. A special
interrupt status register is provided to help software to manage the shared interrupt.
The QSC-100'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 and is
recommended for heavy multitasking environments and for applications involving high data
rates. The larger FIFO allows each read or write access to the UART to move more data,
resulting in fewer interrupts and less processor time spent servicing the UART.
The QSC-100 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 serial device drivers for Windows 95, Windows NT, 98, 2000, Millennium and OS/2
provide support for the UART's 16750 mode.
Quatech QSC-100 User's Manual
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