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Rev. 1.00
494 of 576
January 28, 2022
32-Bit Arm
®
Cortex
®
-M0+ MCU
HT32F54231/HT32F54241/HT32F54243/HT32F54253
23 Universal
Asynchronous Receiver T
ransmitter (UART)
23
23
Universal Asynchronous Receiver
Transmitter (UART)
Introduction
The Universal Asynchronous Receiver Transceiver, UART, provides a flexible full duplex data
exchange using asynchronous transfer. The UART is used to translate data between parallel and
serial interfaces, and is also commonly used for RS232 standard communication. The UART
peripheral function supports a variety of interrupts.
The UART module includes a transmit data register TDR and transmit shift register TSR, and a
receive data register RDR and receive shift register RSR. Software can detect a UART error status
by reading the UART Status & Interrupt Flag Register, URSIFR. The status includes the condition
of the transfer operations as well as several error conditions resulting from Parity, Overrun,
Framing and Break events.
The UART includes a programmable baud rate generator which is capable of dividing the UART
clock CK_APB (CK_UART) to produce a baud rate clock for the UART transmitter and receiver.
APB
Interface
UART
Interrupt
CK_UART
RX
TX
Reference
Divisor Clock
Transmit Data Register (TDR)
Transmit Shift Register (TSR)
Receive Shift Register (RSR)
Receive Data Register (RDR)
Baud Rate
Clock
Generator
UART I/O
UART Control and
Configuration
Registers
TXD
RXD
Figure 180. UART Block Diagram