如何使用I2C来控制BMP180压强传感器？

2720 I2C 传感器

问答对人有帮助，内容完整，我也想知道答案 0 　　今天我们继续使用I2C来控制BMP180压强传感器。BMP180压强传感器操作原理比较简单，开机先通过I2C读取出AC1，AC2，AC3，AC4，AC5，AC6，B1，B2，MB，MC，MD等寄存器的值，这些寄存器的值作为校准时使用。 0
2020-11-5 06:05:37　　评论淘帖0 邀请回答您可以邀请以下用户，快速回答问题 × heks 该类别下有 16 个回答。邀请回答 ChristineGu 该类别下有 16 个回答。邀请回答 HengDu 该类别下有 16 个回答。邀请回答 yonglanzhang 该类别下有 15 个回答。邀请回答 dfasda 该类别下有 15 个回答。邀请回答 nhonglan 该类别下有 15 个回答。邀请回答 wenminglang 该类别下有 14 个回答。邀请回答 C880U 该类别下有 14 个回答。邀请回答 jhdfvs 该类别下有 14 个回答。邀请回答 chm5 该类别下有 14 个回答。邀请回答 muwersddg 该类别下有 14 个回答。邀请回答杀狼000 该类别下有 14 个回答。邀请回答飞雪9366 该类别下有 13 个回答。邀请回答 billbian 该类别下有 13 个回答。邀请回答 a732538 该类别下有 13 个回答。邀请回答 hrtuoyu 该类别下有 13 个回答。邀请回答 hfgdzc 该类别下有 13 个回答。邀请回答 thyysbk 该类别下有 13 个回答。邀请回答凡人wlj 该类别下有 13 个回答。邀请回答 kszdj113 该类别下有 13 个回答。邀请回答举报李秀兰相关推荐 • BMP180 SEN位不设置且操作失败该怎么办？ 1227 • 【求助】BMP180气压传感器的使用 7093 • 怎样去使用一种BMP180气压传感器 1403 • 求助，关于STM8L101和BMP180传感器通信的疑问求解 297 • BMP180传感器怎么从I2C读取多个数据？ 1969 • PIC32蓝牙入门套件I2C通信? 1087 • BMP180做海拔表的海拔不准 3142 • 修改os tick后i2c读写不正确是何原因呢？ 417 • Wemos D1 mini - I2C不工作的原因？ 191 • 请问MPU6050三轴模块怎么接BMP180气压计模块？ 2548 2个回答

答案对人有帮助，有参考价值 0 import time import smbus # BMP085 default address. BMP180_I2CADDR = 0x77 # Operating Modes BMP180_ULTRALOWPOWER = 0 BMP180_STANDARD = 1 BMP180_HIGHRES = 2 BMP180_ULTRAHIGHRES = 3 # BMP085 Registers BMP180_CAL_AC1 = 0xAA # R Calibration data (16 bits) BMP180_CAL_AC2 = 0xAC # R Calibration data (16 bits) BMP180_CAL_AC3 = 0xAE # R Calibration data (16 bits) BMP180_CAL_AC4 = 0xB0 # R Calibration data (16 bits) BMP180_CAL_AC5 = 0xB2 # R Calibration data (16 bits) BMP180_CAL_AC6 = 0xB4 # R Calibration data (16 bits) BMP180_CAL_B1 = 0xB6 # R Calibration data (16 bits) BMP180_CAL_B2 = 0xB8 # R Calibration data (16 bits) BMP180_CAL_MB = 0xBA # R Calibration data (16 bits) BMP180_CAL_MC = 0xBC # R Calibration data (16 bits) BMP180_CAL_MD = 0xBE # R Calibration data (16 bits) BMP180_CONTROL = 0xF4 BMP180_TEMPDATA = 0xF6 BMP180_PRESSUREDATA = 0xF6 # Commands BMP180_READTEMPCMD = 0x2E BMP180_READPRESSURECMD = 0x34 class BMP180(object): def __init__(self, address=BMP180_I2CADDR, mode=BMP180_STANDARD): self._mode = mode self._address = address self._bus = smbus.SMBus(1) # Load calibration values. self._load_calibration() def _read_byte(self,cmd): return self._bus.read_byte_data(self._address,cmd) def _read_u16(self,cmd): MSB = self._bus.read_byte_data(self._address,cmd) LSB = 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): "load calibration" self.cal_AC1 = self._read_s16(BMP180_CAL_AC1) # INT16 self.cal_AC2 = self._read_s16(BMP180_CAL_AC2) # INT16 self.cal_AC3 = self._read_s16(BMP180_CAL_AC3) # INT16 self.cal_AC4 = self._read_u16(BMP180_CAL_AC4) # UINT16 self.cal_AC5 = self._read_u16(BMP180_CAL_AC5) # UINT16 self.cal_AC6 = self._read_u16(BMP180_CAL_AC6) # UINT16 self.cal_B1 = self._read_s16(BMP180_CAL_B1) # INT16 self.cal_B2 = self._read_s16(BMP180_CAL_B2) # INT16 self.cal_MB = self._read_s16(BMP180_CAL_MB) # INT16 self.cal_MC = self._read_s16(BMP180_CAL_MC) # INT16 self.cal_MD = self._read_s16(BMP180_CAL_MD) # INT16 def read_raw_temp(self): """Reads the raw (uncompensated) temperature from the sensor.""" self._write_byte(BMP180_CONTROL, BMP180_READTEMPCMD) time.sleep(0.005) # Wait 5ms MSB = self._read_byte(BMP180_TEMPDATA) LSB = self._read_byte(BMP180_TEMPDATA+1) raw = (MSB << 8) + LSB return raw def read_raw_pressure(self): """Reads the raw (uncompensated) pressure level from the sensor.""" self._write_byte(BMP180_CONTROL, BMP180_READPRESSURECMD + (self._mode << 6)) if self._mode == BMP180_ULTRALOWPOWER: time.sleep(0.005) elif self._mode == BMP180_HIGHRES: time.sleep(0.014) elif self._mode == BMP180_ULTRAHIGHRES: time.sleep(0.026) else: time.sleep(0.008) MSB = self._read_byte(BMP180_PRESSUREDATA) LSB = self._read_byte(BMP180_PRESSUREDATA+1) XLSB = self._read_byte(BMP180_PRESSUREDATA+2) raw = ((MSB << 16) + (LSB << 8) + XLSB) >> (8 - self._mode) return raw def read_temperature(self): """Gets the compensated temperature in degrees celsius.""" UT = self.read_raw_temp() X1 = ((UT - self.cal_AC6) * self.cal_AC5) >> 15 X2 = (self.cal_MC << 11) / (X1 + self.cal_MD) B5 = X1 + X2 temp = ((B5 + 8) >> 4) / 10.0 return temp def read_pressure(self): """Gets the compensated pressure in Pascals.""" UT = self.read_raw_temp() UP = self.read_raw_pressure() X1 = ((UT - self.cal_AC6) * self.cal_AC5) >> 15 X2 = (self.cal_MC << 11) / (X1 + self.cal_MD) B5 = X1 + X2 # Pressure Calculations B6 = B5 - 4000 X1 = (self.cal_B2 * (B6 * B6) >> 12) >> 11 X2 = (self.cal_AC2 * B6) >> 11 X3 = X1 + X2 B3 = (((self.cal_AC1 * 4 + X3) << self._mode) + 2) / 4 X1 = (self.cal_AC3 * B6) >> 13 X2 = (self.cal_B1 * ((B6 * B6) >> 12)) >> 16 X3 = ((X1 + X2) + 2) >> 2 B4 = (self.cal_AC4 * (X3 + 32768)) >> 15 B7 = (UP - B3) * (50000 >> self._mode) 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 p = p + ((X1 + X2 + 3791) >> 4) return p def read_altitude(self, sealevel_pa=101325.0): """Calculates the altitude in meters.""" # Calculation taken straight from section 3.6 of the datasheet. pressure = float(self.read_pressure()) altitude = 44330.0 * (1.0 - pow(pressure / sealevel_pa, (1.0/5.255))) return altitude def read_sealevel_pressure(self, altitude_m=0.0): """Calculates the pressure at sealevel when given a known altitude in meters. Returns a value in Pascals.""" pressure = float(self.read_pressure()) p0 = pressure / pow(1.0 - altitude_m/44330.0, 5.255) return p0

2020-11-5 16:11:47 评论举报刘丽菲

答案对人有帮助，有参考价值 0 主文件bmp180_example.py #!/usr/bin/python import time from BMP180 import BMP180 # Initialise the BMP085 and use STANDARD mode (default value) # bmp = BMP085(0x77, debug=True) bmp = BMP180() # To specify a different operating mode, uncomment one of the following: # bmp = BMP085(0x77, 0) # ULTRALOWPOWER Mode # bmp = BMP085(0x77, 1) # STANDARD Mode # bmp = BMP085(0x77, 2) # HIRES Mode # bmp = BMP085(0x77, 3) # ULTRAHIRES Mode while True: temp = bmp.read_temperature() # Read the current barometric pressure level pressure = bmp.read_pressure() # To calculate altitude based on an estimated mean sea level pressure # (1013.25 hPa) call the function as follows, but this won't be very accurate altitude = bmp.read_altitude() # To specify a more accurate altitude, enter the correct mean sea level # pressure level. For example, if the current pressure level is 1023.50 hPa # enter 102350 since we include two decimal places in the integer value # altitude = bmp.readAltitude(102350) print "Temperature: %.2f C" % temp print "Pressure: %.2f hPa" % (pressure / 100.0) print "Altitude: %.2fn" % altitude time.sleep(1)

2020-11-5 16:12:03 评论举报李正茂