Comments on: MicroPython: ESP32/ESP8266 with DHT11/DHT22 Temperature and Humidity Sensor

By: Sara Santos

Sara Santos — Thu, 15 Feb 2024 10:28:04 +0000

Hi.
What code exactly are you running?
What microdot.py are you referring to?
Regards,
Sara

By: Sky Agnitti

Sky Agnitti — Wed, 14 Feb 2024 22:54:51 +0000

Are the links in this tutorial still working? I keep trying to just use the 2 microdot.py files mentioned but they aren’t available. I’ve tried to use some of the library files for asyncio but I keep getting errors like these:
File “main.py”, line 4, in
File “microdot_asyncio.py”, line 8, in getattr
File “asyncio/init.py”, line 1, in getattr

Any reading this, can you help? I’m trying to have my esp32s running some sort of templated API system and I am at a complete roadblock. Also tried the esp32 – microWebSrv github situation and not much better luck with that though I was able to get the API server to startup.

By: Nando

Nando — Tue, 29 Nov 2022 17:54:52 +0000

temp is class int, can I have class float?

By: David

David — Sat, 14 May 2022 16:30:36 +0000

from dht import DHT22

sensorDHT = DHT22(Pin(32))

By: Ralf

Ralf — Tue, 08 Feb 2022 22:42:12 +0000

May be too late but my experiences showed, that a pullup-resistor to Vcc is essential for reading. I put a 10k resistor from GPIO14 to 3.3V and it works.

By: Vxr

Vxr — Wed, 12 Jan 2022 15:12:34 +0000

Thanks for this tutorial. Very helpful.
Just one mention regarding the DHT11 library – temperature and humidity are now properties so if you want to refer to them don’t use the parenthesis:

from:
temp = sensor.temperature()
hum = sensor.humidity()

to:
temp = sensor.temperature
hum = sensor.humidity

Hope it helps.

By: Daniel Escasa

Daniel Escasa — Fri, 05 Nov 2021 03:31:26 +0000

In reply to Daniel Escasa. Oops, comment in wrong post

By: Daniel Escasa

Daniel Escasa — Thu, 04 Nov 2021 12:25:27 +0000

Excellent tutorial! I got a “Micropython starter kit” which had the exact same boards: an ESP32, an SDD1306, and a DHT11. I was afraid at least the OLED module didn’t work since it didn’t seem to power up whether I connected it to the ESP32, or direct to the breadboard. I think it was uploading ssd1306.py to the board that brought it to life, and I got “Hello World” displayed on it.

I also appended your code for the DHT11 to main.py, modifying it to send output to the OLED module instead. After a little futzing with the parameters to oled.text, the temperature and humidity show up below the Hello World strings.

Next up: a nicer format instead of the bare numbers, and installing larger fonts so the numbers take up more of the screen. The “Hello World” strings can go

By: Sara Santos

Sara Santos — Fri, 09 Oct 2020 10:58:26 +0000

In reply to Nick Cox.

Hi.
Can you try powering the sensor using 5V instead?
I also recommend reading this troubleshooting guide that may help: https://randomnerdtutorials.com/solved-dht11-dht22-failed-to-read-from-dht-sensor/
Regards,
Sara

By: Nick Cox

Nick Cox — Thu, 08 Oct 2020 15:13:24 +0000

Hello!

Please help – I am having trouble making this program work.

Here’s the situation:
-My board is an ESP8266 nodeMCU (Geekreit DOIT ESP-F Devkit v4, if it matters), running MicroPython v. 1.13.
-My DHT11 module is the kind with the little breakout board and three pins – data, power and ground, respectively. I have the data pin attached to GPIO 14 as per your program, and the other pins attached to the adjacent GND and 3V3 pins.

So I copy-pasted your code and uploaded it to my board using Thonny, but all I get is “Failed to read sensor.”

I can blink an LED with this board using MicroPython, so that’s not the problem. I can also get the DHT11 to work with an Arduino, so that’s not the problem either. I have checked the wiring over and over and I know it’s correct. What am I doing wrong?