33 lines
794 B
Python
33 lines
794 B
Python
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# DHT11/DHT22 driver for MicroPython on ESP8266
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# MIT license; Copyright (c) 2016 Damien P. George
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import esp
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class DHTBase:
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def __init__(self, pin):
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self.pin = pin
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self.buf = bytearray(5)
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def measure(self):
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buf = self.buf
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esp.dht_readinto(self.pin, buf)
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if (buf[0] + buf[1] + buf[2] + buf[3]) & 0xff != buf[4]:
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raise Exception("checksum error")
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class DHT11(DHTBase):
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def humidity(self):
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return self.buf[0]
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def temperature(self):
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return self.buf[2]
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class DHT22(DHTBase):
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def humidity(self):
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return (self.buf[0] << 8 | self.buf[1]) * 0.1
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def temperature(self):
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t = ((self.buf[2] & 0x7f) << 8 | self.buf[3]) * 0.1
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if self.buf[2] & 0x80:
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t = -t
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return t
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