GENERAL DESCRIPTION
The XR16C8641 (864) is an enhanced quad Universal Asynchronous Receiver and Transmitter (UART) each with 128 bytes of transmit and receive FIFOs, transmit and receive FIFO counters and trigger levels, automatic hardware and software flow control, automatic RS-485 half-duplex direction control and data rates of up to 2 Mbps. Each UART has a set of registers that provide the user with operating status and control, receiver error indications, and modem serial interface controls.

FEATURES
Added feature in devices with top mark date code of "F2 YYWW" and newer:
   ■ 5 volt tolerant inputs
• 2.97 to 5.5 Volt Operation
• Pin-to-pin compatible with the industry standard
   ST16C554 and ST16C654 and TI’s TL16C554N
   and TL16C754BFN
• Intel or Motorola Data Bus Interface select
• Four independent UART channels
   ■ Register Set Compatible to 16C550
   ■ Data rates of up to 2 Mbps
   ■ Transmit and Receive FIFOs of 128 bytes
   ■ Programmable TX and RX FIFO Trigger Levels
   ■ Transmit and Receive FIFO Level Counters
   ■ Automatic Hardware (RTS/CTS) Flow Control
   ■ Selectable Auto RTS Flow Control Hysteresis
   ■ Automatic Software (Xon/Xoff) Flow Control
   ■ Wireless Infrared (IrDA 1.0) Encoder/Decoder
• Sleep Mode (200 uA typical)
• Crystal oscillator or external clock input

APPLICATIONS
• Portable Appliances
• Telecommunication Network Routers
• Ethernet Network Routers
• Cellular Data Devices
• Factory Automation and Process Controls