一个小小的串口居然让我捣鼓了两天还没出来,时钟正确,usart寄存器值也是对的。然后试了试源码居然一样乱码。不知道是怎么了。板子是官方的
论坛送的
STM32f429zit6。下面贴上代码和源码。
#include quot;stm32f4xx_usart.h quot;
#include quot;stm32f4xx_gpio.h quot;
#include quot;stm32f4xx_rcc.h quot;
#include quot;stm32f4xx_flash.h quot;
#include quot;stm32f4xx_pwr.h quot;
#include quot;stm32f4xx_ex
ti.h quot;
#include quot;misc.h quot;
#include
#include
#include
void USART_GPIO_Config(void);
void USART_Config(void);
void USART_SendString(char *str);
void RCC_Config(void);
void uart3_init(void);
int main(void)
{
SystemInit();
uart3_init();
//USART_GPIO_Config();
USART_Config();
USART_SendData(USART3, '9');
while (USART_GetFlagStatus(USART3, USART_FLAG_TC) == RESET)
{}
while(1)
{
USART_SendData(USART3, 'a');
while (USART_GetFlagStatus(USART3, USART_FLAG_TC) == RESET)
{}
//USART_SendString( quot;hello worldr quot;);
//Array[num++] = USART_ReceiveData(USART1);
//printf( quot;hello world/r quot;);
}
}
void uart3_init(void)
{
USART_InitTypeDef USART_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
/* Enable GPIO clock */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
/* Enable USART clock */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);
/* Connect USART pins to AF7 */
GPIO_PinAFConfig(GPIOC, GPIO_PinSource10, GPIO_AF_USART3);
GPIO_PinAFConfig(GPIOC, GPIO_PinSource11, GPIO_AF_USART3);
/* Configure USART Tx and Rx as alternate function push-pull */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOC, amp;GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOC, amp;GPIO_InitStructure);
}
void USART_SendString(char *str)
{
while(*str!=0)
{
while(RESET == USART_GetFlagStatus(USART1,USART_FLAG_TXE));
USART_SendData(USART1, *str++);
}
}
void USART_Config(void)
{
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);
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_Tx | USART_Mode_Rx;
USART_Init(USART3, amp;USART_InitStructure);
/* NVIC configuration */
/* Configure the Priority Group to 2 bits */
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
/* Enable the USARTx Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init( amp;NVIC_InitStructure);
USART_ITConfig(USART1, USART_IT_TXE|USART_IT_RXNE, ENABLE);
//USART_ITConfig(USART1,USART_IT_CTS, DISABLE);
USART_Cmd(USART3, ENABLE);
}
void uart_init(u32 pclk2,u32 bound)
{
float temp;
u16 mantissa;
u16 fraction;
temp=(float)(pclk2*1000000)/(bound*16);
mantissa=temp;
fraction=(temp-mantissa)*16;
mantissa