一、结构体
USART_TypeDef
/**
* @brief Universal Synchronous Asynchronous Receiver Transmitter
*/
typedef struct
{
__IO uint32_t SR; /*!< USART Status register, Address offset: 0x00 */
__IO uint32_t DR; /*!< USART Data register, Address offset: 0x04 */
__IO uint32_t BRR; /*!< USART Baud rate register, Address offset: 0x08 */
__IO uint32_t CR1; /*!< USART Control register 1, Address offset: 0x0C */
__IO uint32_t CR2; /*!< USART Control register 2, Address offset: 0x10 */
__IO uint32_t CR3; /*!< USART Control register 3, Address offset: 0x14 */
__IO uint32_t GTPR; /*!< USART Guard time and prescaler register, Address offset: 0x18 */
} USART_TypeDef;
SR
是状态寄存器,用于反映串口的各种状态,如发送完成标志、接收完成标志等;
DR
是数据寄存器,用于存储要发送或已经接收的数据;
BRR
是波特率寄存器,用于设置串口的通信波特率;
CR1
、CR2
、CR3
是控制寄存器,用于配置串口的工作模式、数据格式、中断使能等;
GTPR
是保护时间和预分频器寄存器。
UART_InitTypeDef
/**
* @brief UART Init Structure definition
*/
typedef struct
{
uint32_t BaudRate; /*!< This member configures the UART communication baud rate.
The baud rate is computed using the following formula:
- IntegerDivider = ((PCLKx) / (16 * (huart->Init.BaudRate)))
- FractionalDivider = ((IntegerDivider - ((uint32_t) IntegerDivider)) * 16) + 0.5 */
uint32_t WordLength; /*!< Specifies the number of data bits transmitted or received in a frame.
This parameter can be a value of @ref UART_Word_Length */
uint32_t StopBits; /*!< Specifies the number of stop bits transmitted.
This parameter can be a value of @ref UART_Stop_Bits */
uint32_t Parity; /*!< Specifies the parity mode.
This parameter can be a value of @ref UART_Parity