DESCRIPTION
The XR68C92/192 is a Dual Universal Asynchronous Receiver and Transmitter with 8 (XR68C92) / 16 (XR68C192) bytes transmit and receive FIFO. The XR68C92/192 is a pin-to-pin compatible and an improved version of the XR68C681 and the Philips SCC68692 UART with faster data access and other additional features. The operating speed of the receiver and transmitter can be selected independently from a table of eighteen fixed baud rates, a 16X clock derived from a programmable counter/timer, or an external 1X or 16X clock. The baud rate generator and counter/timer can operate directly from a crystal or from external clock input. The XR68C92/192 provides a power-down mode in which the oscillator is stopped but the register contents are retained. The XR68C92/192 is fabricated in an advanced CMOS process to achieve low power and high speed requirements.

FEATURES
Added features in devices with top marking of "D2" and newer:
• 5 volt tolerant inputs
• Pin to pin compatible and improved version of the SCC68692 and XR68C681
• Enhanced Multidrop mode operation with separate storage for address and data tags (9th bit)
• 8 Bytes transmit/receive FIFO (XR68C92)
• 16 Bytes transmit/receive FIFO (XR68C192)
• Standard baud rates from 50bps to 230.4kbps
• Non-standard baud rate of up to 1Mbps
• Transmit and Receive trigger levels
• Watch dog timer
• Programmable clock source for receiver and transmitter of each channel
• Single interrupt output
• 7 Multipurpose inputs, 8 Multipurpose outputs
• 2.97 to 5.5 volt operation
• Programmable character lengths (5, 6, 7, 8)
• Parity, framing, and over run error detection
• Programmable 16-bit timer/counter
• On-chip crystal oscillator
• Power down mode