# DHT11/DHT22 driver for MicroPython on ESP8266

# MIT license; Copyright (c) 2016 Damien P. George

import sys

import machine

if hasattr(machine, "dht_readinto"):

from machine import dht_readinto

elif sys.platform.startswith("esp"):

from esp import dht_readinto

elif sys.platform == "pyboard":

from pyb import dht_readinto

else:

dht_readinto = __import__(sys.platform).dht_readinto

del machine

class DHTBase:

def __init__(self, pin):

self.pin = pin

self.buf = bytearray(5)

def measure(self):

buf = self.buf

dht_readinto(self.pin, buf)

if (buf[0] + buf[1] + buf[2] + buf[3]) & 0xFF != buf[4]:

raise Exception("checksum error")

class DHT11(DHTBase):

def humidity(self):

return self.buf[0]

def temperature(self):

return self.buf[2]

class DHT22(DHTBase):

def humidity(self):

return (self.buf[0] << 8 | self.buf[1]) * 0.1

def temperature(self):

t = ((self.buf[2] & 0x7F) << 8 | self.buf[3]) * 0.1

if self.buf[2] & 0x80:

t = -t

return t