DHT sensor not found, check wiring

I’m using DHT11 on Rpi 4B and I turn to using Adafruit_CircuitPython_DHT today from Adafruit_Python_DHT. I had changed my code to fit the Adafruit_CircuitPython_DHT, but when I run it I meet this error:

Traceback (most recent call last):
  File "tmpv0.2.py", line 44, in <module>
    main()
  File "tmpv0.2.py", line 23, in main
    temperature = dht_device.temperature
  File "/usr/local/lib/python3.8/dist-packages/adafruit_dht.py", line 253, in temperature
    self.measure()
  File "/usr/local/lib/python3.8/dist-packages/adafruit_dht.py", line 205, in measure
    raise RuntimeError("DHT sensor not found, check wiring")
RuntimeError: DHT sensor not found, check wiring

I am sure the connection is fine, because after this error I run the former code and it work perfectly.

Here is the code that has been change to fit Adafruit_CircuitPython_DHT

import datetime
import time

import adafruit_dht
from board import D4
from luma.core.interface.serial import i2c
from luma.core.render import canvas
from luma.oled.device import sh1106
from PIL import ImageFont


# OLED settings
serial = i2c(port=1, address=0x3C)
device = sh1106(serial)
font = ImageFont.truetype('simyou.ttf', 15)

# DHT11 settings
dht_device = adafruit_dht.DHT11(D4)


def main():
    while True:
        temperature = dht_device.temperature
        humidity = dht_device.humidity
        if humidity is not None and temperature is not None:
            Temperature = "温度: {0:0.1f}°C".format(temperature)
            Humidity = "湿度: {0:0.1f}%".format(humidity)
            print(Temperature, Humidity)
            for i in range(0, 10):
                now = datetime.datetime.now()
                today_time = now.strftime("%H:%M:%S")
                with canvas(device) as draw:
                    draw.text((30, 4), today_time, font=font, fill="white")
                    draw.text((10, 23), Temperature, font=font, fill="white")
                    draw.text((10, 42), Humidity, font=font, fill="white")
                time.sleep(0.2)

        else:
            print('失败')


if __name__ == "__main__":
    try:
        main()
    except KeyboardInterrupt:
        device.cleanup()
        pass

And here is the former code

import datetime
import time

import Adafruit_DHT
from luma.core.interface.serial import i2c
from luma.core.render import canvas
from luma.oled.device import sh1106
from PIL import ImageFont

# OLED settings
serial = i2c(port=1, address=0x3C)
device = sh1106(serial)
font = ImageFont.truetype('simyou.ttf', 15)

# DHT11 settings
sensor = Adafruit_DHT.DHT11
DHT11pin = 4


def main():
    while True:
        humidity, temperature = Adafruit_DHT.read_retry(sensor, DHT11pin)
        if humidity is not None and temperature is not None:
            Temperature = "温度: {0:0.1f}°C".format(temperature)
            Humidity = "湿度: {0:0.1f}%".format(humidity)
            print(Temperature, Humidity)
            for i in range(0, 10):
                now = datetime.datetime.now()
                today_time = now.strftime("%H:%M:%S")
                with canvas(device) as draw:
                    draw.text((30, 4), today_time, font=font, fill="white")
                    draw.text((10, 23), Temperature, font=font, fill="white")
                    draw.text((10, 42), Humidity, font=font, fill="white")
                time.sleep(0.2)

        else:
            print('失败')


if __name__ == "__main__":
    try:
        main()
    except KeyboardInterrupt:
        device.cleanup()
        pass

I am new to python and Rpi, and thanks for any help!

[jposada202020]

@Tob1as I review the PR, and I was wrong. Sorry about that. The intended change in 3.5.6 was to addresses mentioned the trigger time for DHT11. However in doing so, I used the ‘//’ division instead of the / division, given a 0 every time. I have just submitted a new PR #64 to correct this. Thank you for pointing that out.

[jposada202020]

@Tob1as Thanks, Changes are merged, they will be released soon!, and thanks fr the feeback and testing on the changes (y)