Introduction

GR551x UART follows the industry-standard 16550 Universal Asynchronous Receiver and Transmitter and the asynchronous part of the RS-232 Serial Protocol. UART is used for serial communication with peripherals, modems (data carrier equipment, DCE), and the like. Data is written from a master (CPU) over the APB bus to the UART, and it is converted to serial form and transmitted to the destination device. Serial data is also received by the UART and stored for the master (CPU) to read back.

GR551x has two UART instances: UART0 and UART1.