导航:USART1程序很多，看看USART2程序。注意红色部分，首先要使能相关端口的时钟。
因为USART2可以映射成不同的端口，所以要端口映射。
结合你自己的开发板，设置正确的映射口.(正点原子的是PA03PA02.)
STM32F103ZE默认的USART2就是PA03PA02，如果配置映射，USART2端口是PD05PD06了。
程序在正点原子开发板SRAM中调试通过，开发环境IAR5.30.
void USART2_IniTIalise( u32 bound )
{
NVIC_InitTypeDef NVIC_InitStructure;//ÖD¶Ï3õê¼»ˉ½á11ìå
USART_InitTypeDef USART_InitStructure;//′®¿ú3õê¼»ˉ½á11ìå
/* Enable the USART2 Pins Software Remapping */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA , ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
/* Configure USART2 Rx (PA.03) as input floaTIng */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Configure USART2 Tx (PA.02) as alternate funcTIon push-pull */
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);
/* Enable the USART2 Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
USART_InitStructure.USART_BaudRate = bound; //ò»°ãéèÖÃÎa9600;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;//×Ö3¤Îa8λêy¾Y¸ñê½
USART_InitStructure.USART_StopBits = USART_StopBits_1; //ò»¸öí￡Ö1λ
USART_InitStructure.USART_Parity = USART_Parity_No; //ÎTÆæżD￡Ñéλ
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//Yá÷¿ØÖÆ
USART_InitStructure.USART_Mode = USART_Mode_Rx " USART_Mode_Tx;//êÕ·￠Ä￡ê½
USART_Init(USART2, &USART_InitStructure);
USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);
//USART_ITConfig(USART2, USART_IT_TXE, ENABLE);
/* Enable USART2 */
USART_Cmd(USART2, ENABLE);
}
void USART2_IRQHandler(void)
{
if(USART_GetFlagStatus(USART2, USART_FLAG_RXNE) == SET)
{
USART_SendData(USART2, USART_ReceiveData(USART2));
}
}
该程序功能是返回你发送到串口的数据。
如果你的USART2接到PD端口上面了，要修改程序如下，这里就需要端口映射了，映射寄存器是AFIO控制的，它接在APB2时钟区域，所以下面的红色代码必须要有，蓝色代码对端口进行初始化。
void USART2_Initialise( u32 bound )
{
GPIO_InitTypeDef GPIO_InitStructure;//I/O¿ú3õê¼»ˉ½á11ìå
NVIC_InitTypeDef NVIC_InitStructure;//ÖD¶Ï3õê¼»ˉ½á11ìå
USART_InitTypeDef USART_InitStructure;//′®¿ú3õê¼»ˉ½á11ìå
/* Enable the USART2 Pins Software Remapping */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD ,ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2,ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);
GPIO_PinRemapConfig(GPIO_Remap_USART2, ENABLE);
/* Configure USART2 Rx (PD.06) as input floating */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOD, &GPIO_InitStructure);
/* Configure USART2 Tx (PD.05) as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOD, &GPIO_InitStructure);
/* Enable the USART2 Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
USART_InitStructure.USART_BaudRate = bound;//ò»°ãéèÖÃÎa9600;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;//×Ö3¤Îa8λêy¾Y¸ñê½
USART_InitStructure.USART_StopBits = USART_StopBits_1;//ò»¸öí￡Ö1λ
USART_InitStructure.USART_Parity = USART_Parity_No;//ÎTÆæżD￡Ñéλ
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//¾Yá÷¿ØÖÆ
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;//êÕ·￠Ä￡ê½
USART_Init(USART2, &USART_InitStructure);
USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);
//USART_ITConfig(USART2, USART_IT_TXE, ENABLE);
/* Enable USART2 */
USART_Cmd(USART2, ENABLE);
}
void USART2_IRQHandler(void)
{
if(USART_GetFlagStatus(USART2, USART_FLAG_RXNE) == SET)
{
USART_SendData(USART2, USART_ReceiveData(USART2));
}
}
该程序功能是返回你发送到串口的数据。
如果你的USART2接到PD端口上面了，要修改程序如下，这里就需要端口映射了，映射寄存器是AFIO控制的，它接在APB2时钟区域，所以下面的红色代码必须要有，蓝色代码对端口进行初始化。
void USART2_Initialise( u32 bound )
{
GPIO_InitTypeDef GPIO_InitStructure;//I/O¿ú3õê¼»ˉ½á11ìå
NVIC_InitTypeDef NVIC_InitStructure;//ÖD¶Ï3õê¼»ˉ½á11ìå
USART_InitTypeDef USART_InitStructure;//′®¿ú3õê¼»ˉ½á11ìå
/* Enable the USART2 Pins Software Remapping */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD ,ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2,ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);
GPIO_PinRemapConfig(GPIO_Remap_USART2, ENABLE);
/* Configure USART2 Rx (PD.06) as input floating */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOD, &GPIO_InitStructure);
/* Configure USART2 Tx (PD.05) as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOD, &GPIO_InitStructure);
/* Enable the USART2 Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
USART_InitStructure.USART_BaudRate = bound;//ò»°ãéèÖÃÎa9600;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;//×Ö3¤Îa8λêy¾Y¸ñê½
USART_InitStructure.USART_StopBits = USART_StopBits_1;//ò»¸öí￡Ö1λ
USART_InitStructure.USART_Parity = USART_Parity_No;//ÎTÆæżD￡Ñéλ
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//¾Yá÷¿ØÖÆ
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //êÕ·￠Ä￡ê½
USART_Init(USART2, &USART_InitStructure);
USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);
//USART_ITConfig(USART2, USART_IT_TXE, ENABLE);
/* Enable USART2 */
USART_Cmd(USART2, ENABLE);
}
void USART2_IRQHandler(void)
{
if(USART_GetFlagStatus(USART2, USART_FLAG_RXNE) == SET)
{
USART_SendData(USART2, USART_ReceiveData(USART2));
}
}