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GD32F20x User Manual
488
19.
Universal
synchronous/asynchronous
receiver
/transmitter (USART)
19.1.
Overview
The Universal Synchronous/Asynchronous Receiver/Transmitter (USART) provides a flexible
serial data exchange interface. Data frames can be transferred in full duplex or half duplex
mode, synchronously or asynchronously through this interface. A programmable baud rate
generator divides the peripheral clock (PCLK1 or PCLK2) to produce a dedicated baud rate
lock for the USART transmitter and receiver.
Besides the standard asynchronous receiver and transmitter mode, the USART implements
several other types of serial data exchange modes, such as IrDA (infrared data association)
SIR mode, smartcard mode, LIN (local interconnection network) mode, half-duplex mode and
synchronous mode. It also supports multiprocessor communication mode, and hardware flow
control protocol (CTS/RTS). The data frame can be transferred from LSB or MSB bit. The
polarity of the data bits and the TX/RX pins can be configured flexibly.
ALL USARTs support DMA function for high-speed data communication.
19.2.
Characteristics
NRZ standard format
Asynchronous, full duplex communication
Programmable baud-rate generator
–
Divided from the peripheral clocks, PCLK2 for USART0/5, PCLK1 for USART1/2
and UART3/4/6/7.
–
Oversampling by 16
–
Maximum speed up to 7.5 MBits/s (PCLK2 120M and oversampling by 16)
Fully programmable serial interface characteristics:
–
Even, odd or no-parity bit generation/detection
–
A data word length can be 8 or 9 bits
–
0.5, 1, 1.5 or 2 stop bit generation
Transmitter and Receiver can be enabled separately
Hardware flow control protocol (CTS/RTS)
DMA request for data buffer access
LIN break generation and detection
IrDA support
Synchronous mode and transmitter clock output for synchronous transmission
Summary of Contents for GD32F20 Series
Page 191: ...GD32F20x User Manual 191 Bits Fields Descriptions 31 0 TRNDATA 31 0 32 Bit Random data ...
Page 290: ...GD32F20x User Manual 290 conversion is ongoing ...
Page 325: ...GD32F20x User Manual 325 15 0 ALRM 15 0 RTC alarm value low ...
Page 385: ...GD32F20x User Manual 385 ...
Page 523: ...GD32F20x User Manual 523 clears AERR bit by writing 0 to it ...