增加 MS5611 气压传感器库

boards/default_src/micropython/origin/build/lib/ms5611.py

@@ -0,0 +1,82 @@
+import utime
+from micropython import const
+
+_MS5611_ADDR     = const(0x77)
+_CMD_ADC_READ    = const(0x00)
+_CMD_RESET       = const(0x1E)
+_CMD_CONVERT_D1  = const(0x40)
+_CMD_CONVERT_D2  = const(0x50)
+_CAL_DATA_C1     = const(0xA2)
+_CAL_DATA_C2     = const(0xA4)
+_CAL_DATA_C3     = const(0xA6)
+_CAL_DATA_C4     = const(0xA8)
+_CAL_DATA_C5     = const(0xAA)
+_CAL_DATA_C6     = const(0xAC)
+
+# Oversampling settings
+OSR={"OSR_256":0, "OSR_512":2, "OSR_1024":4, "OSR_2048":6, "OSR_4096":8}
+
+class MS5611:
+	def __init__(self, i2c_bus, addr=_MS5611_ADDR, osr='OSR_4096'):
+		self._device = i2c_bus
+		self._address = addr
+		self._wreg(_CMD_RESET)
+		utime.sleep_ms(50)
+
+		self.c1 = self._rreg(_CAL_DATA_C1, 2)
+		self.c2 = self._rreg(_CAL_DATA_C2, 2)
+		self.c3 = self._rreg(_CAL_DATA_C3, 2)
+		self.c4 = self._rreg(_CAL_DATA_C4, 2)
+		self.c5 = self._rreg(_CAL_DATA_C5, 2)
+		self.c6 = self._rreg(_CAL_DATA_C6, 2)
+		self.pressure_cmd_rate = _CMD_CONVERT_D1 + OSR[osr]
+		self.temp_cmd_rate = _CMD_CONVERT_D2  + OSR[osr]
+
+	def _wreg(self, val):
+		'''Write memory address'''
+		self._device.writeto(self._address, bytes([val]))
+
+	def _rreg(self, reg, nbytes=1):
+		'''Read memory address'''
+		return int.from_bytes(self._device.readfrom_mem(self._address, reg, nbytes), 'big')
+
+	@property
+	def getdata(self):
+		'''处理获取数据'''
+		self._wreg(self.pressure_cmd_rate)
+		utime.sleep_ms(15)
+		D1 = self._rreg(_CMD_ADC_READ, 3)
+
+		self._wreg(self.temp_cmd_rate)
+		utime.sleep_ms(15)
+		D2 = self._rreg(_CMD_ADC_READ, 3)
+
+		dT = D2 - self.c5 * 2 ** 8
+		TEMP = 2000 + dT * self.c6 / 2 ** 23
+		OFF = self.c2 * 2 ** 16 + dT * self.c4 / 2 ** 7
+		SENS = self.c1 * 2 ** 15 + dT * self.c3 / 2 ** 8
+
+		if TEMP < 2000:
+			T2 = dT * dT / 2 ** 31
+			OFF2 = 5 * (TEMP - 2000) ** 2 / 2
+			SENS2 = 5 * (TEMP - 2000) ** 2 / 4
+			if TEMP < -1500:
+				OFF2 = OFF2 + 7 * (TEMP + 1500) ** 2
+				SENS2 = SENS2 + 11 * (TEMP + 1500) ** 2 / 2
+			TEMP = TEMP - T2
+			OFF = OFF - OFF2
+			SENS = SENS - SENS2
+
+		P = (D1 * SENS / 2 ** 21 - OFF) / 2 ** 15    
+		H = (1 - (P / 101325) ** (1 / 5.255)) * 44330
+
+		return round(P / 100, 2), round(TEMP / 100, 2), round(H, 2)
+
+	def pressure(self): 
+		return self.getdata[0]
+
+	def temperature(self): 
+		return self.getdata[1]
+
+	def altitude(self): 
+		return self.getdata[2]