#This code uses GPIO 17 and 27 As SDA and SCL for i2c bus 3 #add this line to config.txt #dtoverlay=i2c-gpio,bus=3,i2c_gpio_delay_us=1,i2c_gpio_sda=17,i2c_gpio_scl=27 #Restart your raspberry pi #Connect your adafruit BMP388 sensors to i2c bus 1 and 3 import time import smbus import math # define BMP388 Device I2C address I2C_ADD_BMP388_AD0_LOW = 0x76 I2C_ADD_BMP388_AD0_HIGH = 0x77 I2C_ADD_BMP388 = I2C_ADD_BMP388_AD0_LOW BMP388_REG_ADD_WIA = 0x00 BMP388_REG_VAL_WIA = 0x50 BMP388_REG_ADD_ERR = 0x02 BMP388_REG_VAL_FATAL_ERR = 0x01 BMP388_REG_VAL_CMD_ERR = 0x02 BMP388_REG_VAL_CONF_ERR = 0x04 BMP388_REG_ADD_STATUS = 0x03 BMP388_REG_VAL_CMD_RDY = 0x10 BMP388_REG_VAL_DRDY_PRESS = 0x20 BMP388_REG_VAL_DRDY_TEMP = 0x40 BMP388_REG_ADD_CMD = 0x7E BMP388_REG_VAL_EXTMODE_EN = 0x34 BMP388_REG_VAL_FIFI_FLUSH = 0xB0 BMP388_REG_VAL_SOFT_RESET = 0xB6 BMP388_REG_ADD_PWR_CTRL = 0x1B BMP388_REG_VAL_PRESS_EN = 0x01 BMP388_REG_VAL_TEMP_EN = 0x02 BMP388_REG_VAL_NORMAL_MODE = 0x30 BMP388_REG_ADD_PRESS_XLSB = 0x04 BMP388_REG_ADD_PRESS_LSB = 0x05 BMP388_REG_ADD_PRESS_MSB = 0x06 BMP388_REG_ADD_TEMP_XLSB = 0x07 BMP388_REG_ADD_TEMP_LSB = 0x08 BMP388_REG_ADD_TEMP_MSB = 0x09 BMP388_REG_ADD_T1_LSB = 0x31 BMP388_REG_ADD_T1_MSB = 0x32 BMP388_REG_ADD_T2_LSB = 0x33 BMP388_REG_ADD_T2_MSB = 0x34 BMP388_REG_ADD_T3 = 0x35 BMP388_REG_ADD_P1_LSB = 0x36 BMP388_REG_ADD_P1_MSB = 0x37 BMP388_REG_ADD_P2_LSB = 0x38 BMP388_REG_ADD_P2_MSB = 0x39 BMP388_REG_ADD_P3 = 0x3A BMP388_REG_ADD_P4 = 0x3B BMP388_REG_ADD_P5_LSB = 0x3C BMP388_REG_ADD_P5_MSB = 0x3D BMP388_REG_ADD_P6_LSB = 0x3E BMP388_REG_ADD_P6_MSB = 0x3F BMP388_REG_ADD_P7 = 0x40 BMP388_REG_ADD_P8 = 0x41 BMP388_REG_ADD_P9_LSB = 0x42 BMP388_REG_ADD_P9_MSB = 0x43 BMP388_REG_ADD_P10 = 0x44 BMP388_REG_ADD_P11 = 0x45 class BMP388_rain(object): """docstring for BMP388""" def __init__(self, address=I2C_ADD_BMP388): self._address = address self._bus = smbus.SMBus(1) # Load calibration values. if self._read_byte(BMP388_REG_ADD_WIA) == BMP388_REG_VAL_WIA: print("Pressure sersor is BMP388!\r\n") u8RegData = self._read_byte(BMP388_REG_ADD_STATUS) if ( u8RegData & BMP388_REG_VAL_CMD_RDY ): self._write_byte(BMP388_REG_ADD_CMD, BMP388_REG_VAL_SOFT_RESET) time.sleep(0.01) else: print("Pressure sersor NULL!\r\n") self._write_byte( BMP388_REG_ADD_PWR_CTRL,BMP388_REG_VAL_PRESS_EN | BMP388_REG_VAL_TEMP_EN | BMP388_REG_VAL_NORMAL_MODE) self._load_calibration() def _read_byte(self,cmd): return self._bus.read_byte_data(self._address,cmd) def _read_s8(self,cmd): result = self._read_byte(cmd) if result > 128:result -= 256 return result def _read_u16(self,cmd): LSB = self._bus.read_byte_data(self._address,cmd) MSB = self._bus.read_byte_data(self._address,cmd+1) return (MSB << 8) + LSB def _read_s16(self,cmd): result = self._read_u16(cmd) if result > 32767:result -= 65536 return result def _write_byte(self,cmd,val): self._bus.write_byte_data(self._address,cmd,val) def _load_calibration(self): print("_load_calibration\r\n") "load calibration" """ read the temperature calibration parameters """ self.T1 =self._read_u16(BMP388_REG_ADD_T1_LSB) self.T2 =self._read_u16(BMP388_REG_ADD_T2_LSB) self.T3 =self._read_s8(BMP388_REG_ADD_T3) """ read the pressure calibration parameters """ self.P1 =self._read_s16(BMP388_REG_ADD_P1_LSB) self.P2 =self._read_s16(BMP388_REG_ADD_P2_LSB) self.P3 =self._read_s8(BMP388_REG_ADD_P3) self.P4 =self._read_s8(BMP388_REG_ADD_P4) self.P5 =self._read_u16(BMP388_REG_ADD_P5_LSB) self.P6 =self._read_u16(BMP388_REG_ADD_P6_LSB) self.P7 =self._read_s8(BMP388_REG_ADD_P7) self.P8 =self._read_s8(BMP388_REG_ADD_P8) self.P9 =self._read_s16(BMP388_REG_ADD_P9_LSB) self.P10 =self._read_s8(BMP388_REG_ADD_P10) self.P11=self._read_s8(BMP388_REG_ADD_P11) #print(self.T1) #print(self.T2) #print(self.T3) #print(self.P1) #print(self.P2) #print(self.P3) #print(self.P4) #print(self.P5) #print(self.P6) #print(self.P7) #print(self.P8) #print(self.P9) #print(self.P10) #print(self.P11) def compensate_temperature(self,adc_T): partial_data1 = (adc_T - (256 * (self.T1))) partial_data2 = (self.T2 * partial_data1) partial_data3 = (partial_data1 * partial_data1) partial_data4 = (( partial_data3) * ( self.T3)) partial_data5 = ( (( partial_data2) * 262144) + partial_data4) partial_data6 = (( partial_data5) / 4294967296) self.T_fine = partial_data6 comp_temp = ((partial_data6 * 25) / 16384) return comp_temp; def compensate_pressure(self,adc_P): partial_data1 = self.T_fine * self.T_fine partial_data2 = partial_data1 / 64 partial_data3 = (partial_data2 * self.T_fine) / 256 partial_data4 = (self.P8 * partial_data3) / 32 partial_data5 = (self.P7 * partial_data1) * 16 partial_data6 = (self.P6 * self.T_fine) * 4194304; offset = ( (self.P5) * 140737488355328) + partial_data4 + partial_data5 + partial_data6 partial_data2 = (( self.P4) * partial_data3) / 32 partial_data4 = (self.P3 * partial_data1) * 4 partial_data5 = ( (self.P2) - 16384) * ( self.T_fine) * 2097152 sensitivity = (( (self.P1) - 16384) * 70368744177664) + partial_data2 + partial_data4 + partial_data5 partial_data1 = (sensitivity / 16777216) * adc_P partial_data2 = (self.P10) * (self.T_fine) partial_data3 = partial_data2 + (65536 * (self.P9)) partial_data4 = (partial_data3 * adc_P) / 8192 partial_data5 = (partial_data4 * adc_P) / 512 partial_data6 = ( adc_P * adc_P) partial_data2 = ( (self.P11) * (partial_data6)) / 65536 partial_data3 = (partial_data2 * adc_P) / 128 partial_data4 = (offset / 4) + partial_data1 + partial_data5 + partial_data3 comp_press = (( partial_data4 * 25) / 1099511627776) return comp_press; def get_temperature_and_pressure_and_altitude(self): """Returns pressure in Pa as double. Output value of "6386.2"equals 96386.2 Pa = 963.862 hPa.""" xlsb = self._read_byte(BMP388_REG_ADD_TEMP_XLSB) lsb = self._read_byte(BMP388_REG_ADD_TEMP_LSB) msb = self._read_byte(BMP388_REG_ADD_TEMP_MSB) adc_T = (msb << 16) + (lsb << 8) + (xlsb) temperature = self.compensate_temperature(adc_T) xlsb = self._read_byte(BMP388_REG_ADD_PRESS_XLSB) lsb = self._read_byte(BMP388_REG_ADD_PRESS_LSB) msb = self._read_byte(BMP388_REG_ADD_PRESS_MSB) adc_P = (msb << 16) + (lsb << 8) + (xlsb) pressure = self.compensate_pressure(adc_P) altitude = 4433000 * (1 - pow(((pressure/100.0) / 101325.0), 0.1903)) return temperature,pressure,altitude class BMP388_ambient(object): """docstring for BMP388""" def __init__(self, address=I2C_ADD_BMP388): self._address = address self._bus = smbus.SMBus(3) # Load calibration values. if self._read_byte(BMP388_REG_ADD_WIA) == BMP388_REG_VAL_WIA: print("Pressure sersor is BMP388!\r\n") u8RegData = self._read_byte(BMP388_REG_ADD_STATUS) if ( u8RegData & BMP388_REG_VAL_CMD_RDY ): self._write_byte(BMP388_REG_ADD_CMD, BMP388_REG_VAL_SOFT_RESET) time.sleep(0.01) else: print("Pressure sersor NULL!\r\n") self._write_byte( BMP388_REG_ADD_PWR_CTRL,BMP388_REG_VAL_PRESS_EN | BMP388_REG_VAL_TEMP_EN | BMP388_REG_VAL_NORMAL_MODE) self._load_calibration() def _read_byte(self,cmd): return self._bus.read_byte_data(self._address,cmd) def _read_s8(self,cmd): result = self._read_byte(cmd) if result > 128:result -= 256 return result def _read_u16(self,cmd): LSB = self._bus.read_byte_data(self._address,cmd) MSB = self._bus.read_byte_data(self._address,cmd+1) return (MSB << 8) + LSB def _read_s16(self,cmd): result = self._read_u16(cmd) if result > 32767:result -= 65536 return result def _write_byte(self,cmd,val): self._bus.write_byte_data(self._address,cmd,val) def _load_calibration(self): print("_load_calibration\r\n") "load calibration" """ read the temperature calibration parameters """ self.T1 =self._read_u16(BMP388_REG_ADD_T1_LSB) self.T2 =self._read_u16(BMP388_REG_ADD_T2_LSB) self.T3 =self._read_s8(BMP388_REG_ADD_T3) """ read the pressure calibration parameters """ self.P1 =self._read_s16(BMP388_REG_ADD_P1_LSB) self.P2 =self._read_s16(BMP388_REG_ADD_P2_LSB) self.P3 =self._read_s8(BMP388_REG_ADD_P3) self.P4 =self._read_s8(BMP388_REG_ADD_P4) self.P5 =self._read_u16(BMP388_REG_ADD_P5_LSB) self.P6 =self._read_u16(BMP388_REG_ADD_P6_LSB) self.P7 =self._read_s8(BMP388_REG_ADD_P7) self.P8 =self._read_s8(BMP388_REG_ADD_P8) self.P9 =self._read_s16(BMP388_REG_ADD_P9_LSB) self.P10 =self._read_s8(BMP388_REG_ADD_P10) self.P11=self._read_s8(BMP388_REG_ADD_P11) #print(self.T1) #print(self.T2) #print(self.T3) #print(self.P1) #print(self.P2) #print(self.P3) #print(self.P4) #print(self.P5) #print(self.P6) #print(self.P7) #print(self.P8) #print(self.P9) #print(self.P10) #print(self.P11) def compensate_temperature(self,adc_T): partial_data1 = (adc_T - (256 * (self.T1))) partial_data2 = (self.T2 * partial_data1) partial_data3 = (partial_data1 * partial_data1) partial_data4 = (( partial_data3) * ( self.T3)) partial_data5 = ( (( partial_data2) * 262144) + partial_data4) partial_data6 = (( partial_data5) / 4294967296) self.T_fine = partial_data6 comp_temp = ((partial_data6 * 25) / 16384) return comp_temp; def compensate_pressure(self,adc_P): partial_data1 = self.T_fine * self.T_fine partial_data2 = partial_data1 / 64 partial_data3 = (partial_data2 * self.T_fine) / 256 partial_data4 = (self.P8 * partial_data3) / 32 partial_data5 = (self.P7 * partial_data1) * 16 partial_data6 = (self.P6 * self.T_fine) * 4194304; offset = ( (self.P5) * 140737488355328) + partial_data4 + partial_data5 + partial_data6 partial_data2 = (( self.P4) * partial_data3) / 32 partial_data4 = (self.P3 * partial_data1) * 4 partial_data5 = ( (self.P2) - 16384) * ( self.T_fine) * 2097152 sensitivity = (( (self.P1) - 16384) * 70368744177664) + partial_data2 + partial_data4 + partial_data5 partial_data1 = (sensitivity / 16777216) * adc_P partial_data2 = (self.P10) * (self.T_fine) partial_data3 = partial_data2 + (65536 * (self.P9)) partial_data4 = (partial_data3 * adc_P) / 8192 partial_data5 = (partial_data4 * adc_P) / 512 partial_data6 = ( adc_P * adc_P) partial_data2 = ( (self.P11) * (partial_data6)) / 65536 partial_data3 = (partial_data2 * adc_P) / 128 partial_data4 = (offset / 4) + partial_data1 + partial_data5 + partial_data3 comp_press = (( partial_data4 * 25) / 1099511627776) return comp_press; def get_temperature_and_pressure_and_altitude(self): """Returns pressure in Pa as double. Output value of "6386.2"equals 96386.2 Pa = 963.862 hPa.""" xlsb = self._read_byte(BMP388_REG_ADD_TEMP_XLSB) lsb = self._read_byte(BMP388_REG_ADD_TEMP_LSB) msb = self._read_byte(BMP388_REG_ADD_TEMP_MSB) adc_T = (msb << 16) + (lsb << 8) + (xlsb) temperature = self.compensate_temperature(adc_T) xlsb = self._read_byte(BMP388_REG_ADD_PRESS_XLSB) lsb = self._read_byte(BMP388_REG_ADD_PRESS_LSB) msb = self._read_byte(BMP388_REG_ADD_PRESS_MSB) adc_P = (msb << 16) + (lsb << 8) + (xlsb) pressure = self.compensate_pressure(adc_P) altitude = 4433000 * (1 - pow(((pressure/100.0) / 101325.0), 0.1903)) return temperature,pressure,altitude if __name__ == '__main__': import time print("BMP388 Test Program ...\n") bmp388rain = BMP388_rain() bmp388ambient=BMP388_ambient() arainpressure=0 aambientpressure=0 while True: time.sleep(0.5) temperature, rainpressure, altitude = bmp388rain.get_temperature_and_pressure_and_altitude() if arainpressure==0: arainpressure=rainpressure else: arainpressure=(arainpressure*9/10)+(rainpressure*1/10) temperature, ambientpressure, altitude = bmp388ambient.get_temperature_and_pressure_and_altitude() if aambientpressure==0: aambientpressure=ambientpressure else: aambientpressure=(aambientpressure*9/10)+(ambientpressure*1/10) print arainpressure, aambientpressure, float(arainpressure-aambientpressure)