分享：stm32 USART的使用源程序

只看该作者 · 2014-10-31 11:25

#include "stm32f10x_lib.h"
#include"stdio.h"

void RCC_Configuration(void)
{
ErrorStatus HSEStartUpStatus;
/* RCC system reset(for debug purpose) */
RCC_DeInit();       //将外设RCC 寄存器重设为缺省值
/* Enable HSE */
RCC_HSEConfig(RCC_HSE_ON);//使能外部时钟
/* Wait till HSE is ready */
HSEStartUpStatus = RCC_WaitForHSEStartUp();//等待外部时钟就绪
if(HSEStartUpStatus == SUCCESS)
{
/* Enable Prefetch Buffer 启用预取缓冲器 */
FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);

/* Flash 2 wait state FLASH设置2个等待周期*/
FLASH_SetLatency(FLASH_Latency_2);

/* HCLK（AHB时钟） = SYSCLK 设置AHB时钟*/
RCC_HCLKConfig(RCC_SYSCLK_Div1);//AHB(Advanced High performance Bus)系统总线
                                                //APB(Advanced Peripheral Bus)外围总线

/* PCLK2 = HCLK PCLK2时钟=主时钟*/
RCC_PCLK2Config(RCC_HCLK_Div1);

/* PCLK1 = HCLK/2 PCLK1时钟为主时钟1/2*/
RCC_PCLK1Config(RCC_HCLK_Div2);

/* PLLCLK = 8MHz * 9 = 72 MHz 设置时钟为72M，设置PLL时钟源及倍频系数（<=72M）*/
RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);

/* Enable PLL 使能PLL*/
RCC_PLLCmd(ENABLE);

/* Wait till PLL is ready */
while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET);

/* Select PLL as system clock source */
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);

/* Wait till PLL is used as system clock source */
while(RCC_GetSYSCLKSource() != 0x08);
}
}

void USART_configuration(void)
{
USART_InitTypeDef USART_InitStructure;

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(USART1, &USART_InitStructure);
USART_Cmd(USART1, ENABLE);

}
void USART_ClockInitconfiguration(void)
{
USART_ClockInitTypeDef  USART_ClockInitStructuree;
USART_ClockInitStructuree.USART_Clock = USART_Clock_Disable;
USART_ClockInitStructuree.USART_CPOL = USART_CPOL_High;
USART_ClockInitStructuree.USART_CPHA = USART_CPHA_1Edge;
USART_ClockInitStructuree.USART_LastBit = USART_LastBit_Enable;
USART_ClockInit(USART1, &USART_ClockInitStructuree);

}

void GPIO_configuration(void)
{
   GPIO_InitTypeDef GPIO_InitStructure;
   RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_USART1  , ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
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_10;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);
}

int main(void)
{
unsigned char i,data;

RCC_Configuration();
GPIO_configuration();
USART_ClockInitconfiguration();
USART_configuration();
data='A';
for(i=0;i<30;i++)
{
USART_SendData(USART1, data);
data++;
while(USART_GetFlagStatus(USART1, USART_FLAG_TC) ==RESET)       ;

}

  return(1);
}