（1）配置步骤
1.开启RCC外设时钟 开启GPIO以及USART外设
2.初始化GPIO 配置TX复用输出 RX输入
3.配置USART初始化结构体
4.配置串口中断 ITConfig以及NVIC（如果需要USART中断）
5.开启USART
（2）代码示例
案例1 串口异步通信PA9（USART1_TX） 串口发送
void Serial_Init(void)
{
//打开对应总线外设usart以及gpioRCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);//配置引脚作为TX时用复用式推挽输出GPIO_InitTypeDef GPIO_InitStructure;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOA, &GPIO_InitStructure);USART_InitTypeDef USART_InitStructure;
//波特率设置USART_InitStructure.USART_BaudRate = 9600;
//硬件流控制USART_InitStructure.USART_HardwareFlowControl=
USART_HardwareFlowControl_None;
//选择发送模式还是接收模式TX还是RX 如果都需要就或起来USART_InitStructure.USART_Mode = USART_Mode_Tx;
//选择校验 无 奇偶校验USART_InitStructure.USART_Parity = USART_Parity_No;
//选择停止位 一般都是一位USART_InitStructure.USART_StopBits = USART_StopBits_1;
//发送字节长度 8位（一个字节） 或者 9位USART_InitStructure.USART_WordLength = USART_WordLength_8b;USART_Init(USART1, &USART_InitStructure);
//打开串口USART_Cmd(USART1, ENABLE);
}void Serial_SendByte(uint8_t Byte)
{USART_SendData(USART1, Byte);//写入DR
//等待标志位清零while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
}
//发送一个数组
void Serial_SendArray(uint8_t *Array, uint16_t Length)
{uint16_t i;for (i = 0; i < Length; i ++){Serial_SendByte(Array[i]);}
}
//发送一个字符串
void Serial_SendString(char *String)
{uint8_t i;for (i = 0; String[i] != '\0'; i ++){Serial_SendByte(String[i]);}
//注意要善用sprintf
}uint32_t Serial_Pow(uint32_t X, uint32_t Y)
{uint32_t Result = 1;while (Y --){Result *= X;}return Result;
}
//发送一个整型数字
void Serial_SendNumber(uint32_t Number, uint8_t Length)
{uint8_t i;for (i = 0; i < Length; i ++){Serial_SendByte(Number / Serial_Pow(10, Length - i - 1) % 10 + '0');}
}
//可利用printf输出
int fputc(int ch, FILE *f)
{Serial_SendByte(ch);return ch;
}
//对于sprintf进行封装
void Serial_Printf(char *format, ...)
{char String[100];va_list arg;va_start(arg, format);vsprintf(String, format, arg);va_end(arg);Serial_SendString(String);
}案例2 串口中断PA9 10（USART1_TX RX） 串口发送接收
uint8_t Serial_RxData;
uint8_t Serial_RxFlag;
void Serial_Init(void)
{RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);GPIO_InitTypeDef GPIO_InitStructure;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;//复用式推挽输出GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOA, &GPIO_InitStructure);GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;//上拉输入GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOA, &GPIO_InitStructure);USART_InitTypeDef USART_InitStructure;USART_InitStructure.USART_BaudRate = 9600;USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;USART_InitStructure.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;USART_InitStructure.USART_Parity = USART_Parity_No;USART_InitStructure.USART_StopBits = USART_StopBits_1;USART_InitStructure.USART_WordLength = USART_WordLength_8b;USART_Init(USART1, &USART_InitStructure);USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);NVIC_InitTypeDef NVIC_InitStructure;NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;NVIC_Init(&NVIC_InitStructure);USART_Cmd(USART1, ENABLE);
}void Serial_SendByte(uint8_t Byte)
{USART_SendData(USART1, Byte);while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
}void Serial_SendArray(uint8_t *Array, uint16_t Length)
{uint16_t i;for (i = 0; i < Length; i ++){Serial_SendByte(Array[i]);}
}void Serial_SendString(char *String)
{uint8_t i;for (i = 0; String[i] != '\0'; i ++){Serial_SendByte(String[i]);}
}uint32_t Serial_Pow(uint32_t X, uint32_t Y)
{uint32_t Result = 1;while (Y --){Result *= X;}return Result;
}void Serial_SendNumber(uint32_t Number, uint8_t Length)
{uint8_t i;for (i = 0; i < Length; i ++){Serial_SendByte(Number / Serial_Pow(10, Length - i - 1) % 10 + '0');}
}//接收部分
uint8_t Serial_GetRxFlag(void)
{if (Serial_RxFlag == 1){Serial_RxFlag = 0;return 1;}return 0;
}uint8_t Serial_GetRxData(void)
{return Serial_RxData;
}void USART1_IRQHandler(void)
{if (USART_GetITStatus(USART1, USART_IT_RXNE) == SET){Serial_RxData = USART_ReceiveData(USART1);Serial_RxFlag = 1;USART_ClearITPendingBit(USART1, USART_IT_RXNE);}
}
//中断方式接收到的数据回传电脑
int main(void)
{OLED_Init();OLED_ShowString(1, 1, "RxData:");Serial_Init();while (1){if (Serial_GetRxFlag() == 1){RxData = Serial_GetRxData();Serial_SendByte(RxData);OLED_ShowHexNum(1, 8, RxData, 2);}}
}案例3 串口数据包收发流程HEX
uint8_t Serial_TxPacket[4]; //FF 01 02 03 04 FE
uint8_t Serial_RxPacket[4];
uint8_t Serial_RxFlag;void Serial_Init(void)
{RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);GPIO_InitTypeDef GPIO_InitStructure;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOA, &GPIO_InitStructure);GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOA, &GPIO_InitStructure);USART_InitTypeDef USART_InitStructure;USART_InitStructure.USART_BaudRate = 9600;USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;USART_InitStructure.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;USART_InitStructure.USART_Parity = USART_Parity_No;USART_InitStructure.USART_StopBits = USART_StopBits_1;USART_InitStructure.USART_WordLength = USART_WordLength_8b;USART_Init(USART1, &USART_InitStructure);USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);NVIC_InitTypeDef NVIC_InitStructure;NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;NVIC_Init(&NVIC_InitStructure);USART_Cmd(USART1, ENABLE);
}void Serial_SendByte(uint8_t Byte)
{USART_SendData(USART1, Byte);while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
}void Serial_SendArray(uint8_t *Array, uint16_t Length)
{uint16_t i;for (i = 0; i < Length; i ++){Serial_SendByte(Array[i]);}
}void Serial_SendPacket(void)
{Serial_SendByte(0xFF);Serial_SendArray(Serial_TxPacket, 4);Serial_SendByte(0xFE);
}uint8_t Serial_GetRxFlag(void)
{if (Serial_RxFlag == 1){Serial_RxFlag = 0;return 1;}return 0;
}void USART1_IRQHandler(void)
{static uint8_t RxState = 0;static uint8_t pRxPacket = 0;if (USART_GetITStatus(USART1, USART_IT_RXNE) == SET){uint8_t RxData = USART_ReceiveData(USART1);if (RxState == 0){if (RxData == 0xFF){RxState = 1;pRxPacket = 0;}}else if (RxState == 1){Serial_RxPacket[pRxPacket] = RxData;pRxPacket ++;if (pRxPacket >= 4){RxState = 2;}}else if (RxState == 2){if (RxData == 0xFE){RxState = 0;Serial_RxFlag = 1;}}USART_ClearITPendingBit(USART1, USART_IT_RXNE);}
}uint8_t KeyNum;
int main(void)
{OLED_Init();Key_Init();Serial_Init();OLED_ShowString(1, 1, "TxPacket");OLED_ShowString(3, 1, "RxPacket");Serial_TxPacket[0] = 0x01;Serial_TxPacket[1] = 0x02;Serial_TxPacket[2] = 0x03;Serial_TxPacket[3] = 0x04;while (1){KeyNum = Key_GetNum();if (KeyNum == 1){Serial_TxPacket[0] ++;Serial_TxPacket[1] ++;Serial_TxPacket[2] ++;Serial_TxPacket[3] ++;Serial_SendPacket();OLED_ShowHexNum(2, 1, Serial_TxPacket[0], 2);OLED_ShowHexNum(2, 4, Serial_TxPacket[1], 2);OLED_ShowHexNum(2, 7, Serial_TxPacket[2], 2);OLED_ShowHexNum(2, 10, Serial_TxPacket[3], 2);}if (Serial_GetRxFlag() == 1){OLED_ShowHexNum(4, 1, Serial_RxPacket[0], 2);OLED_ShowHexNum(4, 4, Serial_RxPacket[1], 2);OLED_ShowHexNum(4, 7, Serial_RxPacket[2], 2);OLED_ShowHexNum(4, 10, Serial_RxPacket[3], 2);}}
}
