CODE EXAMPLES

import RPi.GPIO as GPIO

import time

 

def bin2dec(string_num):

    return str(int(string_num, 2))

 

data = []

 

GPIO.setmode(GPIO.BCM)

 

GPIO.setup(4,GPIO.OUT)

GPIO.output(4,GPIO.HIGH)

time.sleep(0.025)

GPIO.output(4,GPIO.LOW)

time.sleep(0.02)

 

GPIO.setup(4, GPIO.IN, pull_up_down=GPIO.PUD_UP)

 

for i in range(0,500):

    data.append(GPIO.input(4))

 

bit_count = 0

tmp = 0

count = 0

HumidityBit = ""

TemperatureBit = ""

crc = ""

 

try:

while data[count] == 1:

tmp = 1

count = count + 1

 

for i in range(0, 32):

bit_count = 0

 

while data[count] == 0:

tmp = 1

count = count + 1

 

while data[count] == 1:

bit_count = bit_count + 1

count = count + 1

 

if bit_count > 3:

if i>=0 and i<8:

HumidityBit = HumidityBit + "1"

if i>=16 and i<24:

TemperatureBit = TemperatureBit + "1"

else:

if i>=0 and i<8:

HumidityBit = HumidityBit + "0"

if i>=16 and i<24:

TemperatureBit = TemperatureBit + "0"

 

except:

print "ERR_RANGE"

exit(0)

 

try:

for i in range(0, 8):

bit_count = 0

 

while data[count] == 0:

tmp = 1

count = count + 1

 

while data[count] == 1:

bit_count = bit_count + 1

count = count + 1

 

if bit_count > 3:

crc = crc + "1"

else:

crc = crc + "0"

except:

print "ERR_RANGE"

exit(0)

 

Humidity = bin2dec(HumidityBit)

Temperature = bin2dec(TemperatureBit)

 

if int(Humidity) + int(Temperature) - int(bin2dec(crc)) == 0:

print "Humidity:"+ Humidity +"%"

print "Temperature:"+ Temperature +"C"

else:

print "ERR_CRC"