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通过C#上位机串口写入和读取浮点数到stm32实战5（通过串口读取bmp280气压计的数值并在上位机显示）

news 2025/8/26 7:48:25

网上很多代码i2c的连续读函数都不能正确读到bmp280数据，但读得到芯片ID=0x58，原因在于bmp280内置校准值T1-T3,P1-P9是高8位和低8位构成的，不能直接读取，需做处理，详细见下面代码。

文章后有完整代码和上位机代码下载

通过网盘分享的文件：bmp280.rar
链接: https://pan.baidu.com/s/1giTtMOVrnCl4eUBVCIsFqA 提取码: abcd

bmp280.h

#ifndef __BMP280_H
#define __BMP280_H
//#include "sys.h"
//#include "stdbool.h"//typedef enum {FALSE=0,TRUE=1} bool;#define BMP280_ADDR				        	(0xEC)
#define BMP280_DEFAULT_CHIP_ID			(0x58)#define BMP280_CHIP_ID					(0xD0)                                 /* Chip ID Register */
#define BMP280_RST_REG					(0xE0)                                 /* Softreset Register */
#define BMP280_STAT_REG					(0xF3)                                 /* Status Register */
#define BMP280_CTRL_MEAS_REG			(0xF4)                                 /* Ctrl Measure Register */
#define BMP280_CONFIG_REG				(0xF5)                                 /* Configuration Register */
#define BMP280_PRESSURE_MSB_REG			(0xF7)                                 /* Pressure MSB Register */
#define BMP280_PRESSURE_LSB_REG			(0xF8)                                 /* Pressure LSB Register */
#define BMP280_PRESSURE_XLSB_REG		(0xF9)                                 /* Pressure XLSB Register */
#define BMP280_TEMPERATURE_MSB_REG		(0xFA)                                 /* Temperature MSB Reg */
#define BMP280_TEMPERATURE_LSB_REG		(0xFB)                                 /* Temperature LSB Reg */
#define BMP280_TEMPERATURE_XLSB_REG		(0xFC)                                 /* Temperature XLSB Reg */#define BMP280_SLEEP_MODE				(0x00)
#define BMP280_FORCED_MODE				(0x01)
#define BMP280_NORMAL_MODE				(0x03)#define BMP280_TEMPERATURE_CALIB_DIG_T1_LSB_REG             (0x88)
#define BMP280_PRESSURE_TEMPERATURE_CALIB_DATA_LENGTH       (24)
#define BMP280_DATA_FRAME_SIZE			(6)#define BMP280_OVERSAMP_SKIPPED			(0x00)
#define BMP280_OVERSAMP_1X				(0x01)
#define BMP280_OVERSAMP_2X				(0x02)
#define BMP280_OVERSAMP_4X				(0x03)
#define BMP280_OVERSAMP_8X				(0x04)
#define BMP280_OVERSAMP_16X				(0x05)//自己补充
#define BMP280_DIG_T1_LSB_REG                0x88
#define BMP280_DIG_T1_MSB_REG                0x89
#define BMP280_DIG_T2_LSB_REG                0x8A
#define BMP280_DIG_T2_MSB_REG                0x8B
#define BMP280_DIG_T3_LSB_REG                0x8C
#define BMP280_DIG_T3_MSB_REG                0x8D
#define BMP280_DIG_P1_LSB_REG                0x8E
#define BMP280_DIG_P1_MSB_REG                0x8F
#define BMP280_DIG_P2_LSB_REG                0x90
#define BMP280_DIG_P2_MSB_REG                0x91
#define BMP280_DIG_P3_LSB_REG                0x92
#define BMP280_DIG_P3_MSB_REG                0x93
#define BMP280_DIG_P4_LSB_REG                0x94
#define BMP280_DIG_P4_MSB_REG                0x95
#define BMP280_DIG_P5_LSB_REG                0x96
#define BMP280_DIG_P5_MSB_REG                0x97
#define BMP280_DIG_P6_LSB_REG                0x98
#define BMP280_DIG_P6_MSB_REG                0x99
#define BMP280_DIG_P7_LSB_REG                0x9A
#define BMP280_DIG_P7_MSB_REG                0x9B
#define BMP280_DIG_P8_LSB_REG                0x9C
#define BMP280_DIG_P8_MSB_REG                0x9D
#define BMP280_DIG_P9_LSB_REG                0x9E
#define BMP280_DIG_P9_MSB_REG                0x9Fbool bmp280Init(void);
void bmp280GetData(float* pressure, float* temperature, float* asl);#endif

bmp280.c

#include <math.h>
//#include "stdbool.h"
#include "delay.h"
#include "i2c.h"
#include "bmp280.h"
//#include "usart.h"/*bmp280 气压和温度过采样 工作模式*/
#define BMP280_PRESSURE_OSR			(BMP280_OVERSAMP_8X)
#define BMP280_TEMPERATURE_OSR		(BMP280_OVERSAMP_16X)
#define BMP280_MODE					(BMP280_PRESSURE_OSR<<2|BMP280_TEMPERATURE_OSR<<5|BMP280_NORMAL_MODE)typedef struct 
{u16 dig_T1;                                                                /* calibration T1 data */s16 dig_T2;                                                                /* calibration T2 data */s16 dig_T3;                                                                /* calibration T3 data */u16 dig_P1;                                                                /* calibration P1 data */s16 dig_P2;                                                                /* calibration P2 data */s16 dig_P3;                                                                /* calibration P3 data */s16 dig_P4;                                                                /* calibration P4 data */s16 dig_P5;                                                                /* calibration P5 data */s16 dig_P6;                                                                /* calibration P6 data */s16 dig_P7;                                                                /* calibration P7 data */s16 dig_P8;                                                                /* calibration P8 data */s16 dig_P9;                                                                /* calibration P9 data */s32 t_fine;                                                                /* calibration t_fine data */
} bmp280Calib;bmp280Calib  bmp280Cal;u8 bmp280ID=0;
static bool isInit=FALSE;
static s32 bmp280RawPressure=0;
static s32 bmp280RawTemperature=0;static void bmp280GetPressure(void);
static void presssureFilter(float* in,float* out);
static float bmp280PressureToAltitude(float* pressure/*, float* groundPressure, float* groundTemp*/);bool bmp280Init(void)
{	if (isInit)return TRUE;//IIC_Init();		                                                           /*初始化I2C*/delay_ms(20);bmp280ID=iicDevReadByte(BMP280_ADDR,BMP280_CHIP_ID);	                   /* 读取bmp280 ID*//*if(bmp280ID==BMP280_DEFAULT_CHIP_ID)printf("BMP280 ID IS: 0x%X\n",bmp280ID);elsereturn false;
*//* 读取校准数据 */// iicDevRead(BMP280_ADDR,BMP280_TEMPERATURE_CALIB_DIG_T1_LSB_REG,24,(u8 *)&bmp280Cal);uint8_t lsb, msb;/* read the temperature calibration parameters */   // 读取校准数据 自己改的，因为连续读函数有问题lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_T1_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_T1_MSB_REG);bmp280Cal.dig_T1 = msb << 8 | lsb;lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_T2_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_T2_MSB_REG);bmp280Cal.dig_T2 = msb << 8 | lsb;lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_T3_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_T3_MSB_REG);bmp280Cal.dig_T3 = msb << 8 | lsb;/* read the pressure calibration parameters */lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P1_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P1_MSB_REG);bmp280Cal.dig_P1 = msb << 8 | lsb;lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P2_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P2_MSB_REG);bmp280Cal.dig_P2  = msb << 8 | lsb;lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P3_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P3_MSB_REG);bmp280Cal.dig_P3 = msb << 8 | lsb;lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P4_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P4_MSB_REG);bmp280Cal.dig_P4  = msb << 8 | lsb;lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P5_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P5_MSB_REG);bmp280Cal.dig_P5  = msb << 8 | lsb;lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P6_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P6_MSB_REG);bmp280Cal.dig_P6  = msb << 8 | lsb;lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P7_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P7_MSB_REG);bmp280Cal.dig_P7  = msb << 8 | lsb;lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P8_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P8_MSB_REG);bmp280Cal.dig_P8  = msb << 8 | lsb;lsb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P9_LSB_REG);msb = iicDevReadByte(BMP280_ADDR,BMP280_DIG_P9_MSB_REG);bmp280Cal.dig_P9  = msb << 8 | lsb;iicDevWriteByte(BMP280_ADDR,BMP280_CTRL_MEAS_REG,BMP280_MODE);iicDevWriteByte(BMP280_ADDR,BMP280_CONFIG_REG,5<<2);		               /*配置IIR滤波*///	printf("BMP280 Calibrate Registor Are: \r\n");
//	for(i=0;i<24;i++)
//		printf("Registor %2d: 0x%X\n",i,p[i]);isInit=TRUE;return TRUE;
}static void bmp280GetPressure(void)
{u8 data[BMP280_DATA_FRAME_SIZE];// read data from sensor//iicDevRead(BMP280_ADDR,BMP280_PRESSURE_MSB_REG,BMP280_DATA_FRAME_SIZE,data);data[0]=iicDevReadByte(BMP280_ADDR,BMP280_PRESSURE_MSB_REG );	  //自己改的data[1]=iicDevReadByte(BMP280_ADDR,BMP280_PRESSURE_LSB_REG );	data[2]=iicDevReadByte(BMP280_ADDR,BMP280_PRESSURE_XLSB_REG );	data[3]=iicDevReadByte(BMP280_ADDR,BMP280_TEMPERATURE_MSB_REG );	  //自己改的data[4]=iicDevReadByte(BMP280_ADDR,BMP280_TEMPERATURE_LSB_REG );	data[5]=iicDevReadByte(BMP280_ADDR,BMP280_TEMPERATURE_XLSB_REG );	bmp280RawPressure=(s32)((((uint32_t)(data[0]))<<12)|(((uint32_t)(data[1]))<<4)|((uint32_t)data[2]>>4));bmp280RawTemperature=(s32)((((uint32_t)(data[3]))<<12)|(((uint32_t)(data[4]))<<4)|((uint32_t)data[5]>>4));
}// Returns temperature in DegC, resolution is 0.01 DegC. Output value of "5123" equals 51.23 DegC
// t_fine carries fine temperature as global value
static s32 bmp280CompensateT(s32 adcT)
{s32 var1,var2,T;var1=((((adcT>>3)-((s32)bmp280Cal.dig_T1<<1)))*((s32)bmp280Cal.dig_T2))>>11;var2=(((((adcT>>4)-((s32)bmp280Cal.dig_T1))*((adcT>>4)-((s32)bmp280Cal.dig_T1)))>>12)*((s32)bmp280Cal.dig_T3))>>14;bmp280Cal.t_fine=var1+var2;T=(bmp280Cal.t_fine*5+128)>>8;return T;
}// Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24 integer bits and 8 fractional bits).
// Output value of "24674867" represents 24674867/256 = 96386.2 Pa = 963.862 hPa
static uint32_t bmp280CompensateP(s32 adcP)
{int64_t var1,var2,p;var1=((int64_t)bmp280Cal.t_fine)-128000;var2=var1*var1*(int64_t)bmp280Cal.dig_P6;var2=var2+((var1*(int64_t)bmp280Cal.dig_P5)<<17);var2=var2+(((int64_t)bmp280Cal.dig_P4)<<35);var1=((var1*var1*(int64_t)bmp280Cal.dig_P3)>>8)+((var1*(int64_t)bmp280Cal.dig_P2)<<12);var1=(((((int64_t)1)<<47)+var1))*((int64_t)bmp280Cal.dig_P1)>>33;if (var1==0)return 0;p=1048576-adcP;p=(((p<<31)-var2)*3125)/var1;var1=(((int64_t)bmp280Cal.dig_P9)*(p>>13)*(p>>13))>>25;var2=(((int64_t)bmp280Cal.dig_P8)*p)>>19;p=((p+var1+var2)>>8)+(((int64_t)bmp280Cal.dig_P7)<<4);return(uint32_t)p;
}#define FILTER_NUM	5
#define FILTER_A	0.1f/*限幅平均滤波法*/
static void presssureFilter(float* in,float* out)
{	static u8 i=0;static float filter_buf[FILTER_NUM]={0.0};double filter_sum=0.0;u8 cnt=0;	float deta;if(filter_buf[i]==0.0f){filter_buf[i]=*in;*out=*in;if(++i>=FILTER_NUM)	i=0;} else {if(i)deta=*in-filter_buf[i-1];else deta=*in-filter_buf[FILTER_NUM-1];if(fabs(deta)<FILTER_A){filter_buf[i]=*in;if(++i>=FILTER_NUM)	i=0;}for(cnt=0;cnt<FILTER_NUM;cnt++){filter_sum+=filter_buf[cnt];}*out=filter_sum /FILTER_NUM;}
}void bmp280GetData(float* pressure,float* temperature,float* asl)
{static float t;static float p;bmp280GetPressure();t=bmp280CompensateT(bmp280RawTemperature)/100.0;		p=bmp280CompensateP(bmp280RawPressure)/25600.0;		presssureFilter(&p,pressure);*temperature=(float)t;                                                     /*单位度*/
//	*pressure=(float)p ;	                                                   /*单位hPa*/	*asl=bmp280PressureToAltitude(pressure);	                               /*转换成海拔*/	
}#define CONST_PF 0.1902630958	                                               //(1/5.25588f) Pressure factor
#define FIX_TEMP 25				                                               // Fixed Temperature. ASL is a function of pressure and temperature, but as the temperature changes so much (blow a little towards the flie and watch it drop 5 degrees) it corrupts the ASL estimates.// TLDR: Adjusting for temp changes does more harm than good.
/** Converts pressure to altitude above sea level (ASL) in meters
*/
static float bmp280PressureToAltitude(float* pressure/*, float* groundPressure, float* groundTemp*/)
{if (*pressure>0){return((pow((1015.7f/ *pressure),CONST_PF)-1.0f)*(FIX_TEMP+273.15f))/0.0065f;}else{return 0;}
}

i2c.h

#ifndef _I2C_H
#define _I2C_Htypedef enum {FALSE=0,TRUE=1} bool;void I2C_GPIO_Config(void);  //mpu9250 输入定义
void I2C_delay(void);	
void delay5ms(void);
bool I2C_Start(void);
void I2C_Stop(void);
void I2C_Ack(void);
void I2C_NoAck(void);
bool I2C_WaitAck(void);
void I2C_SendByte(u8 SendByte); //数据从高位到低位//
unsigned char I2C_RadeByte(void);  //数据从高位到低位//
bool Single_Write(unsigned char SlaveAddress,unsigned char REG_Address,unsigned char REG_data);
unsigned char Single_Read(unsigned char SlaveAddress,unsigned char REG_Address);
void WWDG_Configuration(void);
void WWDG_IRQHandler(void);u8 iicDevReadByte(u8 devaddr,u8 addr);	                                       /*读一字节*/
void iicDevWriteByte(u8 devaddr,u8 addr,u8 data);	                           /*写一字节*/
void iicDevRead(u8 devaddr,u8 addr,u8 len,u8 *rbuf);                           /*连续读取多个字节*/
void iicDevWrite(u8 devaddr,u8 addr,u8 len,u8 *wbuf);          
/*连续写入多个字节*/#endif

i2c.c

#include "stm32f10x.h"
#include "i2c.h"char  test=0; 				 //IIC//************************************
/*模拟IIC端口输出输入定义*/
#define SCL_H         GPIOB->BSRR = GPIO_Pin_6
#define SCL_L         GPIOB->BRR  = GPIO_Pin_6 #define SDA_H         GPIOB->BSRR = GPIO_Pin_7
#define SDA_L         GPIOB->BRR  = GPIO_Pin_7#define SCL_read      GPIOB->IDR  & GPIO_Pin_6
#define SDA_read      GPIOB->IDR  & GPIO_Pin_7/*******************************************************************************
* Function Name  : I2C_GPIO_Config
* Description    : Configration Simulation IIC GPIO
* Input          : None 
* Output         : None
* Return         : None
****************************************************************************** */
void I2C_GPIO_Config(void)  //mpu9250 输入定义
{GPIO_InitTypeDef  GPIO_InitStructure; GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_6;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz; //GPIO_Speed_50MHz;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_OD;  GPIO_Init(GPIOB, &GPIO_InitStructure);GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_7;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz; //GPIO_Speed_50MHz;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_OD;GPIO_Init(GPIOB, &GPIO_InitStructure);
}/*******************************************************************************
* Function Name  : I2C_delay
* Description    : Simulation IIC Timing series delay
* Input          : None
* Output         : None
* Return         : None
****************************************************************************** */
void I2C_delay(void)
{u8 i=8;  // 30 这里可以优化速度	，经测试最低到5还能写入while(i) { i--; }  
}void delay5ms(void)
{int i=1000;  while(i) { i--; }  
}
/*******************************************************************************
* Function Name  : I2C_Start
* Description    : Master Start Simulation IIC Communication
* Input          : None
* Output         : None
* Return         : Wheather	 Start
****************************************************************************** */
bool I2C_Start(void)
{SDA_H;SCL_H;I2C_delay();if(!SDA_read)return FALSE;	//SDA线为低电平则总线忙,退出SDA_L;I2C_delay();if(SDA_read) return FALSE;	//SDA线为高电平则总线出错,退出SDA_L;I2C_delay();return TRUE;
}
/*******************************************************************************
* Function Name  : I2C_Stop
* Description    : Master Stop Simulation IIC Communication
* Input          : None
* Output         : None
* Return         : None
****************************************************************************** */
void I2C_Stop(void)
{SCL_L;I2C_delay();SDA_L;I2C_delay();SCL_H;I2C_delay();SDA_H;I2C_delay();
} 
/*******************************************************************************
* Function Name  : I2C_Ack
* Description    : Master Send Acknowledge Single
* Input          : None
* Output         : None
* Return         : None
****************************************************************************** */
void I2C_Ack(void)
{	SCL_L;I2C_delay();SDA_L;I2C_delay();SCL_H;I2C_delay();SCL_L;I2C_delay();
}   
/*******************************************************************************
* Function Name  : I2C_NoAck
* Description    : Master Send No Acknowledge Single
* Input          : None
* Output         : None
* Return         : None
****************************************************************************** */
void I2C_NoAck(void)
{	SCL_L;I2C_delay();SDA_H;I2C_delay();SCL_H;I2C_delay();SCL_L;I2C_delay();
} 
/*******************************************************************************
* Function Name  : I2C_WaitAck
* Description    : Master Reserive Slave Acknowledge Single
* Input          : None
* Output         : None
* Return         : Wheather	 Reserive Slave Acknowledge Single
****************************************************************************** */
bool I2C_WaitAck(void) 	  //返回为:=1有ACK,=0无ACK
{SCL_L;I2C_delay();SDA_H;			I2C_delay();SCL_H;I2C_delay();if(SDA_read){SCL_L;I2C_delay();return FALSE;}SCL_L;I2C_delay();return TRUE;
}
/*******************************************************************************
* Function Name  : I2C_SendByte
* Description    : Master Send a Byte to Slave
* Input          : Will Send Date
* Output         : None
* Return         : None
****************************************************************************** */
void I2C_SendByte(u8 SendByte) //数据从高位到低位//
{u8 i=8;while(i--){SCL_L;I2C_delay();if(SendByte&0x80)SDA_H;  else SDA_L;   SendByte<<=1;I2C_delay();SCL_H;I2C_delay();}SCL_L;
}  
/*******************************************************************************
* Function Name  : I2C_RadeByte
* Description    : Master Reserive a Byte From Slave
* Input          : None
* Output         : None
* Return         : Date From Slave 
****************************************************************************** */
unsigned char I2C_RadeByte(void)  //数据从高位到低位//
{ u8 i=8;u8 ReceiveByte=0;SDA_H;				while(i--){ReceiveByte<<=1;      SCL_L;I2C_delay();SCL_H;I2C_delay();	if(SDA_read){ReceiveByte|=0x01;}}SCL_L;return ReceiveByte;
} 
//ZRX          
//?????*******************************************bool Single_Write(unsigned char SlaveAddress,unsigned char REG_Address,unsigned char REG_data)		     //void
{if(!I2C_Start())return FALSE;I2C_SendByte(SlaveAddress);   //发送设备地址+写信号//I2C_SendByte(((REG_Address & 0x0700) >>7) | SlaveAddress & 0xFFFE);//设置高起始地址+器件地址 if(!I2C_WaitAck()){I2C_Stop(); return FALSE;}I2C_SendByte(REG_Address );   //设置低起始地址      I2C_WaitAck();	I2C_SendByte(REG_data);I2C_WaitAck();   I2C_Stop(); delay5ms();return TRUE;
}//单字节读取*****************************************
unsigned char Single_Read(unsigned char SlaveAddress,unsigned char REG_Address)
{   unsigned char REG_data;     	if(!I2C_Start())return FALSE;I2C_SendByte(SlaveAddress);   //I2C_SendByte(((REG_Address & 0x0700) >>7) | REG_Address & 0xFFFE);//设置高起始地址+器件地址 if(!I2C_WaitAck()){I2C_Stop();test=1; return FALSE;}I2C_SendByte((u8) REG_Address);   //设置高起始地址+器件地址 I2C_WaitAck();I2C_Start();I2C_SendByte(SlaveAddress+1);I2C_WaitAck();REG_data= I2C_RadeByte();I2C_NoAck();I2C_Stop();//return TRUE;return REG_data;}		u8 iicDevReadByte(u8 devaddr,u8 addr) /*读一字节*/
{u8 data; data=Single_Read(devaddr,addr);return data;
}
void iicDevWriteByte(u8 devaddr,u8 addr,u8 data)	/*写一字节*/
{Single_Write(devaddr,addr,data);	
}
void iicDevRead(u8 devaddr,u8 addr,u8 len,u8 *rbuf)/*连续读取多个字节*/
{}
void iicDevWrite(u8 devaddr,u8 addr,u8 len,u8 *wbuf)    
{}/*
********************************************************************************
** 函数名称 ： WWDG_Configuration(void)
** 函数功能 ： 看门狗初始化
** 输    入	： 无
** 输    出	： 无
** 返    回	： 无
********************************************************************************
*/
void WWDG_Configuration(void)
{RCC_APB1PeriphClockCmd(RCC_APB1Periph_WWDG, ENABLE);	WWDG_SetPrescaler(WWDG_Prescaler_8);	              //  WWDG clock counter = (PCLK1/4096)/8 = 244 Hz (~4 ms)  WWDG_SetWindowValue(0x41);		                 // Set Window value to 0x41WWDG_Enable(0x50);		       // Enable WWDG and set counter value to 0x7F, WWDG timeout = ~4 ms * 64 = 262 ms WWDG_ClearFlag();			       // Clear EWI flagWWDG_EnableIT();			       // Enable EW interrupt
}/*
********************************************************************************
** 函数名称 ： WWDG_IRQHandler(void)
** 函数功能 ： 窗口提前唤醒中断
** 输    入	： 无
** 输    出	： 无
** 返    回	： 无
********************************************************************************
*/ void WWDG_IRQHandler(void)
{/* Update WWDG counter */WWDG_SetCounter(0x50);/* Clear EWI flag */WWDG_ClearFlag(); 
}//************************************************

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