The UPD8251AF is a Programmable Communication Interface (USART) designed for serial data communication. Manufactured by NEC, it's a versatile device that supports both synchronous and asynchronous communication protocols. It's commonly used to interface microprocessors and microcontrollers with serial devices such as modems, printers, and other peripherals.
Applications
- Serial Communication: Interfacing microprocessors with serial devices such as modems, printers, and other peripherals.
- Computer Peripherals: Connecting computers to serial printers, terminals, and other legacy devices.
- Data Acquisition Systems: Implementing serial communication links for data acquisition and control systems.
- Industrial Control: Used in industrial control systems for serial communication between controllers and remote devices.
- Networking: Implementing serial communication protocols in networking applications.
Features
- Programmable Baud Rate: Supports a wide range of programmable baud rates for flexible communication.
- Synchronous and Asynchronous Modes: Operates in both synchronous and asynchronous communication modes.
- Full-Duplex Operation: Supports full-duplex communication, allowing simultaneous transmission and reception.
- Error Detection: Includes error detection capabilities such as parity checking and framing error detection.
- Data Length Selection: Supports programmable data length (5-8 bits) for compatibility with various devices.
- Interrupt-Driven Operation: Can be configured for interrupt-driven operation, enabling efficient handling of serial data.
Benefits
- Versatile Communication: Supports both synchronous and asynchronous communication protocols for flexible interfacing.
- Flexible Baud Rate: Programmable baud rate allows for compatibility with a wide range of serial devices.
- Efficient Data Transfer: Full-duplex operation enables simultaneous transmission and reception, maximizing data throughput.
- Reliable Data Transmission: Error detection capabilities ensure reliable data transmission and reduce errors.
- Simplified Interface: Provides a simplified interface between microprocessors and serial devices.
Additional Details
The UPD8251AF requires a clock signal for operation. The baud rate is determined by a programmable divider. It utilizes control registers for configuring the communication parameters, such as baud rate, data length, parity, and mode. The device communicates with the microprocessor through a data bus and control signals. It is typically used with a UART driver in software to manage the serial communication process. The device is often used in legacy systems and can be found in older computer peripherals and industrial equipment.
