气压传感器BMP180驱动（stm32f103）

#include "BMP180.h" #include "delay.h" //PA6--SCL PA7--SDA //I2C总线初始化 //配置SDA信号线为输入模式 u8 BMP_communication_sta = 1; void BMP180_SDA_Input_Mode() { GPIO_InitTypeDef GPIO_InitStructure; GPIO_InitStructure.GPIO_Pin = BMP180_SDA; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; GPIO_Init(BMP180_I2C_PORT, &GPIO_InitStructure); } //配置SDA信号线为输出模式 void BMP180_SDA_Output_Mode() { GPIO_InitTypeDef GPIO_InitStructure; GPIO_InitStructure.GPIO_Pin = BMP180_SDA; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; GPIO_Init(BMP180_I2C_PORT, &GPIO_InitStructure); } void BMP180_SDA_Output( uint16_t val ) { if ( val ) { GPIO_SetBits(BMP180_I2C_PORT,BMP180_SDA); } else { GPIO_ResetBits(BMP180_I2C_PORT,BMP180_SDA); } } // uint8_t BMP180_SDA_Input() { return GPIO_ReadInputDataBit(BMP180_I2C_PORT, BMP180_SDA); } // void BMP180_SCL_Output( uint16_t val ) { if ( val ) { GPIO_SetBits(BMP180_I2C_PORT,BMP180_SCL); } else { GPIO_ResetBits(BMP180_I2C_PORT,BMP180_SCL); } } //延时程序 void BMP180_delay1(unsigned int n) { unsigned int i; for ( i=0;i<n;++i); } //I2C总线启动 void BMP180_I2CStart(void) { BMP180_SDA_Output(1);BMP180_delay1(500); BMP180_SCL_Output(1);BMP180_delay1(500); BMP180_SDA_Output(0);BMP180_delay1(500); BMP180_SCL_Output(0);BMP180_delay1(500); } //I2C总线停止 void BMP180_I2CStop(void) { BMP180_SCL_Output(0); BMP180_delay1(500); BMP180_SDA_Output(0); BMP180_delay1(500); BMP180_SCL_Output(1); BMP180_delay1(500); BMP180_SDA_Output(1); BMP180_delay1(500); } //等待应答 unsigned char BMP180_I2CWaitAck(void) { unsigned short cErrTime = 5; BMP180_SDA_Input_Mode(); BMP180_delay1(500); BMP180_SCL_Output(1); BMP180_delay1(500); while(BMP180_SDA_Input()) { cErrTime--; BMP180_delay1(500); if (0 == cErrTime) { BMP180_SDA_Output_Mode(); BMP_communication_sta = 0; BMP180_I2CStop(); return 0; } } BMP180_SDA_Output_Mode(); BMP180_SCL_Output(0); BMP180_delay1(500); return 1; } //发送应答位 void BMP180_I2CSendAck(void) { BMP180_SDA_Output(0); BMP180_delay1(500); BMP180_delay1(500); BMP180_SCL_Output(1); BMP180_delay1(500); BMP180_SCL_Output(0); BMP180_delay1(500); } // void BMP180_I2CSendNotAck(void) { BMP180_SDA_Output(1); BMP180_delay1(500); BMP180_SCL_Output(1); BMP180_delay1(500); BMP180_SCL_Output(0); BMP180_delay1(500); } //通过I2C总线发送一个字节数据 void BMP180_I2CSendByte(unsigned char cSendByte) { unsigned char i = 8; while (i--) { BMP180_SCL_Output(0); BMP180_delay1(500); BMP180_SDA_Output(cSendByte & 0x80); BMP180_delay1(500); cSendByte += cSendByte; BMP180_delay1(500); BMP180_SCL_Output(1); BMP180_delay1(500); } BMP180_SCL_Output(0); BMP180_delay1(500); } //从I2C总线接收一个字节数据 unsigned char BMP180_I2CReceiveByte(void) { unsigned char i = 8; unsigned char cR_Byte = 0; BMP180_SDA_Input_Mode(); while (i--) { cR_Byte += cR_Byte; BMP180_SCL_Output(0); BMP180_delay1(500); BMP180_delay1(500); BMP180_SCL_Output(1); BMP180_delay1(500); cR_Byte |= BMP180_SDA_Input(); } BMP180_SCL_Output(0); BMP180_delay1(500); BMP180_SDA_Output_Mode(); return cR_Byte; } //单字节写入BMP180内部数据 void BMP180_Write(u8 REG_Address, u8 data) { BMP180_I2CStart(); BMP180_I2CSendByte(BMP180_Address); BMP180_I2CWaitAck(); BMP180_I2CSendByte(REG_Address); BMP180_I2CWaitAck(); BMP180_I2CSendByte(data); BMP180_I2CWaitAck(); BMP180_I2CStop(); delay_ms(1); } //单字节读取BMP180内部数据******************************** u8 BMP180_Read_Single(u8 REG_Address) { u8 data; BMP180_I2CStart(); //起始信号 BMP180_I2CSendByte(BMP180_Address); //发送设备地址+写信号 BMP180_I2CWaitAck(); BMP180_I2CSendByte(REG_Address); //发送存储单元地址 BMP180_I2CWaitAck(); BMP180_I2CStart(); //起始信号 BMP180_I2CSendByte(BMP180_Address | 0x01); //发送设备地址+读信号 BMP180_I2CWaitAck(); data=BMP180_I2CReceiveByte(); //读出寄存器数据 BMP180_I2CSendNotAck(); BMP180_I2CStop(); //停止信号 BMP180_delay1(500); return data; } //读出BMP180内部数据,连续两个 //********************************************************* u16 BMP180_Read_Multiple(u8 REG_Address) { u8 MSB, LSB; u16 data; BMP180_I2CStart(); //起始信号 BMP180_I2CSendByte(BMP180_Address); //发送设备地址+写信号 BMP180_I2CWaitAck(); BMP180_I2CSendByte(REG_Address); //发送存储单元地址 BMP180_I2CWaitAck(); BMP180_I2CStart(); //起始信号 BMP180_I2CSendByte(BMP180_Address | 0x01); //发送设备地址+读信号 BMP180_I2CWaitAck(); MSB = BMP180_I2CReceiveByte(); //BUF[0]存储 BMP180_I2CSendAck(); ; //回应ACK LSB = BMP180_I2CReceiveByte(); BMP180_I2CSendNotAck(); //最后一个数据需要回NOACK BMP180_I2CStop(); //停止信号 BMP180_delay1(500); data = MSB << 8 | LSB; return data; } int16_t AC1,AC2,AC3,B1,B2,MB,MC,MD; uint16_t AC4,AC5,AC6; void BMP180_ReadCalvalue(void) { AC1 = BMP180_Read_Multiple(0xAA); AC2 = BMP180_Read_Multiple(0xAC); AC3 = BMP180_Read_Multiple(0xAE); AC4 = BMP180_Read_Multiple(0xB0); AC5 = BMP180_Read_Multiple(0xB2); AC6 = BMP180_Read_Multiple(0xB4); B1 = BMP180_Read_Multiple(0xB6); B2 = BMP180_Read_Multiple(0xB8); MB = BMP180_Read_Multiple(0xBA); MC = BMP180_Read_Multiple(0xBC); MD = BMP180_Read_Multiple(0xBE); } long BMP180_ReadTemp(void) { BMP180_Write(CTRL_MEAS, 0x2E); //Max. conversion time 4.5ms delay_ms(5); return (int64_t)BMP180_Read_Multiple(OUT_MSB); } //************************************************************* long BMP180_ReadPressure(void) { u16 pressure = 0; BMP180_Write(CTRL_MEAS, 0x34); //Max. conversion time 4.5ms delay_ms(5); pressure = BMP180_Read_Multiple(OUT_MSB); pressure &= 0x0000FFFF; return (int64_t)pressure; } //获得BMP180的温度和气压值 #define OSS 0 void Read_BMP180_Date(u16 *Temp, u32 *Press, u32 *altitude) { int64_t X1,X2,X3,B3,B5,B6,B7,P,tmp,pre; uint64_t B4; tmp = BMP180_ReadTemp(); pre = BMP180_ReadPressure(); //计算温度 temp in 0.1°C X1 = (tmp - AC6) * AC5 >> 15; //X1 = (UT - AC6) * AC5 / 2^15 X2 = (MC << 11) / (X1 + MD); //X2 = MC * 2^11 / (X1 + MD) B5 = X1 + X2; //B5 = X1 + X2 *Temp = (B5 + 8) >> 4; //T = (B5 + 8) / 2^4 //计算压强 press in Pa B6 = B5 - 4000; X1 = (B2 * (B6 * B6 >> 12)) >> 11; X2 = AC2 * B6 >> 11; X3 = X1 + X2; B3 = ((AC1 * 4 + X3) + 2)/4; X1 = AC3 * B6 >> 13; X2 = (B1 * (B6 * B6 >> 12)) >> 16; X3 = ((X1 + X2) + 2) >> 2; B4 = (AC4 * (X3 + 32768)) >> 15; B7 = ((uint64_t) pre - B3) * (50000 >> OSS); if( B7 < 0x80000000) P = (B7 * 2) / B4 ; else P = (B7 / B4) * 2; X1 = (P >> 8) * (P >> 8); X1 = (X1 * 3038) >> 16; X2 = (-7357 * P) >> 16; *Press = P + ((X1 + X2 + 3791) >> 4); *altitude = *Press; *altitude = (101325 - (float)*altitude) / 100 * 843;// 1hPa = 8.43m } //读SHT30状态 u8 Read_BMP180_ID(void) { BMP180_ReadCalvalue(); return BMP180_Read_Single(BMP180_ID); } void BMP180_Init(void) { GPIO_InitTypeDef GPIO_InitStructure; RCC_APB2PeriphClockCmd(BMP180_RCC, ENABLE); GPIO_InitStructure.GPIO_Pin = BMP180_SDA | BMP180_SCL; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; // ** GPIO_Init(BMP180_I2C_PORT, &GPIO_InitStructure); GPIO_SetBits(BMP180_I2C_PORT,BMP180_SDA);