The XR68C681N is a dual universal asynchronous receiver/transmitter (DUART) manufactured by Exar Corporation. It provides two independent full-duplex asynchronous communication channels, each with its own baud rate generator and interrupt control. It is designed for serial data communication in a wide range of applications, including computer peripherals, industrial control systems, and communication devices.

Applications:

• Computer Peripherals: Connecting serial devices such as printers, modems, and scanners.
• Industrial Control Systems: Interfacing with sensors, actuators, and other industrial equipment.
• Communication Devices: Implementing serial communication protocols in routers, switches, and other network devices.
• Point-of-Sale (POS) Systems: Connecting barcode scanners, receipt printers, and other POS peripherals.
• Embedded Systems: Providing serial communication capabilities for microcontrollers and embedded processors.

Features:

• Dual UART Channels: Provides two independent serial communication channels.
• Programmable Baud Rate Generator: Supports a wide range of baud rates for flexible communication.
• FIFO Buffers: Reduces CPU overhead by buffering transmit and receive data.
• Interrupt Control: Generates interrupts for efficient data handling.
• Modem Control Signals: Supports modem control functions such as CTS, RTS, DSR, and DCD.
• Programmable Data Format: Supports various data formats, including different word lengths and parity options.

Benefits:

• Versatile Serial Communication: Supports a wide range of serial communication applications.
• Efficient Data Handling: FIFO buffers and interrupt control minimize CPU overhead.
• Flexible Baud Rate Configuration: Supports various baud rates for compatibility with different devices.
• Modem Control Support: Enables communication with modems and other DCE devices.
• Easy Integration: Simplifies system design with its comprehensive feature set.

The XR68C681N operates from a single 5V power supply. It supports various communication protocols, including RS-232, RS-422, and RS-485, with appropriate external transceivers. The device is available in a DIP package. The UART includes features such as parity generation and checking, framing error detection, and overrun error detection. These features enhance the reliability and robustness of serial communication. The XR68C681N is commonly used in embedded systems and industrial automation applications where reliable serial communication is essential.