应该都是不直接连电脑的串口,而是通过板子上的ch340转usb,
虽说usart可以异步通信,但发现还是速度慢,提高波特率后速度快了很多,256000输出1000次直观看不到1秒,这样就可以接收了
初始化usart,仅发送模式
void USART1_Init_SendOnly(u32 bound)
{
//GPIO¶Ë¿ÚÉèÖÃ
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE); //´ò¿ªÊ±ÖÓ
/* ÅäÖÃGPIOµÄģʽºÍIO¿Ú */
GPIO_InitStructure.GPIO_Pin=GPIO_Pin_9;//TX //´®¿ÚÊä³öPA9
GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AF_PP; //¸´ÓÃÍÆÍìÊä³ö
GPIO_Init(GPIOA,&GPIO_InitStructure); /* ³õʼ»¯´®¿ÚÊäÈëIO */
GPIO_InitStructure.GPIO_Pin=GPIO_Pin_10;//RX //´®¿ÚÊäÈëPA10
GPIO_InitStructure.GPIO_Mode=GPIO_Mode_IN_FLOATING; //Ä£ÄâÊäÈë
GPIO_Init(GPIOA,&GPIO_InitStructure); /* ³õʼ»¯GPIO */
//USART1 ³õʼ»¯ÉèÖÃ
USART_InitStructure.USART_BaudRate = bound;//²¨ÌØÂÊÉèÖÃ
USART_InitStructure.USART_WordLength = USART_WordLength_8b;//×Ö³¤Îª8λÊý¾Ý¸ñʽ
USART_InitStructure.USART_StopBits = USART_StopBits_1;//Ò»¸öֹͣλ
USART_InitStructure.USART_Parity = USART_Parity_No;//ÎÞÆæżУÑéλ
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//ÎÞÓ²¼þÊý¾ÝÁ÷¿ØÖÆ
USART_InitStructure.USART_Mode = USART_Mode_Tx; //only ·¢Ä£Ê½
USART_Init(USART1, &USART_InitStructure); //³õʼ»¯´®¿Ú1
USART_Cmd(USART1, ENABLE); //ʹÄÜ´®¿Ú1
USART_ClearFlag(USART1, USART_FLAG_TC);
// USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);//¿ªÆôÏà¹ØÖжÏ
//Usart1 NVIC ÅäÖÃ
// NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;//´®¿Ú1ÖжÏͨµÀ
// NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3;//ÇÀÕ¼ÓÅÏȼ¶3
// NVIC_InitStructure.NVIC_IRQChannelSubPriority =3; //×ÓÓÅÏȼ¶3
// NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQͨµÀʹÄÜ
// NVIC_Init(&NVIC_InitStructure); //¸ù¾ÝÖ¸¶¨µÄ²ÎÊý³õʼ»¯VIC¼Ä´æÆ÷¡¢
}
https://blog.csdn.net/justsure91/article/details/81081161
哎组成原理没好好学呀