GENERAL DESCRIPTION
   The XR17D1541 (D154) is a quad PCI Bus Universal Asynchronous Receiver and Transmitter (UART) with same package and pin-out as the Exar XR17C158, XR17D158 and XR17C154. The device is designed to meet today’s 32-bit PCI Bus and high bandwidth requirement in communication systems. The global interrupt source register provides a complete interrupt status indication for all 4 channels to speed up interrupt parsing. 

FEATURES
● High Performance Quad PCI UART
● Universal PCI Bus Buffers - Auto-sense 3.3V or 5V
   Operation
● 32-bit PCI Bus 2.3 Target Signalling Compliance
● A Global Interrupt Source Register for all 4 UARTs
● Data Transfer in Byte, Word and Double-word
● Data Read/Write Burst Operation
● Each UART is independently controlled with:
   ■ 16C550 Compatible 5G Register Set
   ■ 64-byte Transmit and Receive FIFOs
   ■ Transmit and Receive FIFO Level Counters
   ■ Automatic RTS/CTS or DTR/DSR Flow Control
   ■ Automatic Xon/Xoff Software Flow Control
   ■ Automatic RS485 Half-duplex Control Output
      with Selectable Turn-around Delay
   ■ Infrared (IrDA 1.0) Data Encoder/Decoder
   ■ Programmable Data Rate with Prescaler
   ■ Up to 6.25 Mbps Serial Data Rate at 8X
● Eight Multi-Purpose Inputs/outputs
● General Purpose 16-bit Timer/Counter
● Sleep Mode with Automatic Wake-up
● EEPROM Interface for PCI Configuration
● Same package and pin-out as the XR17D158,
   XR17C158 and XR17C154 (20x20x1.4mm 144-
   TQFP)

APPLICATIONS
● Universal Form Factor PCI Bus Add-in Card
● Remote Access Servers
● Ethernet Network to Serial Ports
● Network Management
● Factory Automation and Process Control
● Point-of-Sale Systems
● Multi-port RS-232/RS-422/RS-485 Cards