DHT 11 - Sensor with Raspberry Pi

Question

OK, This is a little frustrating as I am JUST trying to get the temperature/Humidity readings on my DHT 11 sensor with Raspberry pi 4 and I am unable to do so. Please see below

https://www.electronicwings.com/raspberry-pi/dht11-interfacing-with-raspberry-pi

I get an error asking me to run the same as sudo.

Then after I try to run the program as a sudo user I get the following error repeatedly:

"Failed to get the readin. Try Again"

I even tried changing the sensor to no avail....

There were some posts suggesting a different version as the Adafruit function does not seem support the latest hardware. However there does not seem to be a proper closure to any of the posts. I also tried this

https://stackoverflow.com/questions/63232072/cannot-import-name-beaglebone-black-driver-from-adafruit-dht

Any help is appreciated.

---

Ok So like Dougie suggested I went to the post and downloaded DHT.PY

Reliable temperature/humidity logging with Python and a DHT11

After downloading DHT.Py , I ran the script mentioned in the link above and then when i ran I do not see any error message nor do i see any out put

I also ensured to keep the DHT.Py and the script that i am running in the same folder...(Double checked pins , nothing much to check anyways, there is ground , power and pin 4 (BCM)), SO it is not the circuit or the sensor , so I ma guessing it must be code. I also did sudo pigpiod before I ran all this..

Am i just being plain stupid or is this really an issue ??

Answer 1

The code I ACTUALLY use is raspberrypi.stackexchange.com/a/105549/8697
This doesn't actually output anything and only posts a single MQTT message.

The following simplified code prints a single reading.

#!/usr/bin/env python3

# 2020-09-27
"""
    A Program to read the DHTXX temperature/humidity sensors.

    REQUIREMENTS
    DHT.py    download "module" from http://abyz.me.uk/rpi/pigpio/code/DHT.py
    pigpiod running
"""

import sys
import pigpio
import DHT
import time
import datetime

# Sensor should be set to DHT.DHT11, DHT.DHTXX or DHT.DHTAUTO
sensor = DHT.DHT11

pin = 4     # Data - Pin 7 (BCM 4)

def output_data(timestamp, temperature, humidity):
    # Sample output Date: 2019-11-17T10:55:08, Temperature: 25°C, Humidity: 72%
    date = datetime.datetime.fromtimestamp(timestamp).replace(microsecond=0).isoformat()
    print(u"Date: {:s}, Temperature: {:g}\u00b0C, Humidity: {:g}%".format(date, temperature, humidity))

pi = pigpio.pi()
if not pi.connected:
  exit()

s = DHT.sensor(pi, pin, model = sensor)

tries = 5   # try 5 times if error
while tries:
    try:
        timestamp, gpio, status, temperature, humidity = s.read()   #read DHT device
        if(status == DHT.DHT_TIMEOUT):  # no response from sensor
            exit()
        if(status == DHT.DHT_GOOD):
            output_data(timestamp, temperature, humidity)
            exit()      # Exit after successful read
        time.sleep(2)
        tries -=1
    except KeyboardInterrupt:
        break

Answer 2

from pigpio_dht import DHT11, DHT22

gpio = 4 # BCM Numbering

sensor = DHT11(gpio)
#sensor = DHT22(gpio)

result = sensor.read()
print(result)

Even I had the same problem..This worked for me you can also try once. Before running the code enter the commands on the terminal

sudo pigpiod #Start daemon

pigs pud 4 u # Set internal pull up

If pigpio-dht is not installed enter pip3 install pigpio-dht and run the above program