高时间要求下的usart通信

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