The XR16V7981 (798), is a 2.25V to 3.6V octal Universal Asynchronous Receiver and Transmitter (UART) with 5V tolerant serial (modem) inputs. The highly integrated device is designed for high bandwidth requirement in communication systems. The global interrupt source register provides a complete interrupt status indication for all 8 channels to speed up interrupt parsing. Each UART has its own 16C550 compatible set of configuration registers, TX and RX FIFOs of 64 bytes, fully programmable transmit and receive FIFO trigger levels, TX and RX FIFO level counters, automatic RTS/CTS or DTR/ DSR hardware flow control with programmable hysteresis, autoamtic software (Xon/Xoff) flow control, RS-485 half-duplex direction control with programmable turn-around delay, Intel or Motorola bus interface and sleep mode with a wake-up indicator.