demo.dtu/dtu/t_h.py

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2022-01-14 10:53:40 +08:00
from machine import I2C
import utime as time
class SensorTH:
def __init__(self):
# super(SensorTH, self).__init__()
self.i2cn = I2C.I2C1
self.i2c_mode = I2C.STANDARD_MODE
self.i2c = I2C(self.i2cn, self.i2c_mode)
self.data_cache = None
self._init_cmd()
self.sensor_init()
def _init_cmd(self):
# Initialization command
self.CALIBRATION_CMD = 0xE1
# Trigger measurement
self.START_MEASURMENT_CMD = 0xAC
# reset
self.RESET_CMD = 0xBA
# slave address
self.i2c_addr = 0X38
def write_data(self, data):
self.i2c.write(self.i2c_addr,
bytearray(0x00), 0,
bytearray(data), len(data))
def read_data(self, length):
r_data = [0x00 for i in range(length)]
r_data = bytearray(r_data)
self.i2c.read(self.i2c_addr,
bytearray(0x00), 0,
r_data, length,
0)
return list(r_data)
def sensor_init(self):
# 上电等待校准数据。 发送 0xE1 0x08 0x00
self.write_data([self.CALIBRATION_CMD, 0x08, 0x00])
time.sleep_ms(300) # at last 300ms
def sensor_reset(self):
self.write_data([self.RESET_CMD])
time.sleep_ms(20) # at last 20ms
def _get_datas(self, length):
# Trigger data conversion
# 触发测量,发送 0xAC, 0x33 0x00
self.write_data([self.START_MEASURMENT_CMD, 0x33, 0x00])
time.sleep_ms(200) # at last delay 75ms
data = [0x00 for i in range(length)]
data = bytearray(data)
self.i2c.read(self.i2c_addr,
bytearray(0x00), 0,
data, length, 0)
self.data_cache = list(data)
def _humidity_transformat(self):
data = self.data_cache[1:6]
humidity = (data[0] << 12) | (
data[1] << 4) | ((data[2] & 0xF0) >> 4)
return round((humidity / (1 << 20)) * 100.0, 2)
def _temperature_transformat(self):
data = self.data_cache[1:6]
temperature = ((data[2] & 0xf) << 16) | (
data[3] << 8) | data[4]
return round((temperature * 200.0 / (1 << 20)) - 50, 2)
def read_temperature(self):
# self.sensor_reset()
self._get_datas(6)
# check bit7
if (self.data_cache[0] >> 7) != 0x0:
pass
return False
temperature = self._temperature_transformat()
return temperature
def read_humidity(self):
# self.sensor_reset()
self._get_datas(6)
if (self.data_cache[0] >> 7) != 0x0:
pass
return False
humidity = self._humidity_transformat()
return humidity
def read(self):
# self.sensor_reset()
self._get_datas(6)
if (self.data_cache[0] >> 7) != 0x0:
pass
return False
return self._temperature_transformat(), self._humidity_transformat()