第7章 STM32通用同步异步收发器USART3.ppt

USART_InitStructure.USART_BaudRate = 9600; USART_InitStructure.USART_WordLength = USART_WordLength_8b; USART_InitStructure.USART_StopBits = USART_StopBits_1; USART_InitStructure.USART_Parity = USART_Parity_No; USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None; USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; USART_Init(USART1, USART_InitStructure); USART_Cmd(USART1, ENABLE); } 7.5.3 USART应用设计1——串口收发数据(串口程序2) 将程序下载到开发板，通过串口与PC机相连，打开串口调试助手，串口调试助手显示 7.5.3 USART通信实例2——串口发送数据 例2：用串口2发送数据，上位机使用串口调试工具接收并显示。串口发送完数据后跳变LED2灯。 7.5.3 USART通信实例2——串口发送数据(主程序) int main(void) { SystemInit(); //配置系统时钟 gpio_conf(); //初始化LED和按键IO口 USART2_Config(); //初始化串口 while (1) { for(unsigned int i=0;i0xfffe;i++) { for(unsigned char k=0;k9;k++) asm(nop); } Usart2_PutChar(0x34) ; //从串口2发送数据 LED2B(); } } 7.5.3 USART应用设计2——串口发送数据(串口设置1) void USART2_Config(void) { //1)定义初始化结构体 GPIO_InitTypeDef GPIO_InitStructure; USART_InitTypeDef USART_InitStructure; //2)开启时钟 RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_AFIO, ENABLE); RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE); 7.5.3 USART应用设计2——串口发送数据(串口设置2) //3)IO口初始化 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; GPIO_Init(GPIOA,GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING; GPIO_Init(GPIOA, GPIO_InitStructure); 7.5.3 USART应用设计2——串口发送数据(串口设置3) //4)串口参数初始化 USART_InitStructure.USART_BaudRate = 115200; USART_InitStructure.USART_WordLength = USART_WordLength_8b; USART_InitStructure.USART_StopBits = USART_StopBits_1; USART_InitStructure.USART_Parity = USART_Parity_No; USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None; USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; USART_I