MMM-DHT22

JohnGalt

@BKeyport thanks for the response. It looks like my issue is actually with the Linux 12 / bookworm version of Raspbian I installed when rebuilding my MagicMirror, as opposed to the R-Pi 4 hardware.

In reading the Adafruit forums here: https://forums.adafruit.com/viewtopic.php?p=938344&hilit=Adafruit_Python_DHT#p938344 I find the official Adafruit response to someone with the same issues is that “DHT22 really sucks to use on linux” and … “you will be a lot happier just using the DHT20 and friends”, with a reference to an Adafruit web article at https://learn.adafruit.com/modern-replacements-for-dht11-dht22-sensors/overview.

In short, the advice is to just buy all new sensors for your Raspberry Pi installs. The OP pointed out that while he acknowledges the newer sensors may indeed be better, that " I spent a good amount of money buying and building, and for all of that to go away with an update really stinks! :( ".

I agree with him since I have probably five (5) DHT 11/22 sensors working on R-Pis, and while it looks like he found a way to upgrade all pip libraries and get it working again, it also appears to only be a matter of time until another update or upgrade of something breaks the system.

Again thanks for pointing me in the right direction.

BKeyport

@JohnGalt I’m betting LadyAda and co are working on a fix all the same. They’re big on keeping old hardware working.

JohnGalt

@BKeyport - That has been my general impression of Adafruit, and for the sake of general continuity, I do hope that is the case. All that said, the situation with the sensor libraries has been a mess for years - with my personal favorite gripe being libraries being deprecated without clear messaging on the website hosting the old, together with new libraries with very similar names but different functionality. For the life of me I cannot understand why simply incrementing the version numbering wouldn’t have accomplished what was needed [accompanied of course, by clear messaging…].

Meanwhile I have ordered and received some DHT20 sensors, and will soon begin standing some of those up. This has entailed first building a development instance to work on, as I find the MagicMirror system to be fragile, and I want to minimize downtime on the production instance. As of yesterday I do have the dev instance running and am trying to iron out a couple of wrinkles, like tracking down why and how the default calendar module on the new dev instance doesn’t display recurring appointments the same as on the existing [production] instance. Seeing as I literally copied and pasted the configuration code from the old to the new, I would think it would perform the same.

Anyway - thanks again for the input and the guidance, as always.

Michi0904

This post is deleted!

Jimmy1502

Hello, im quite new to the MagicMirror and I only have basic Programming Knowledge. I tried using ur Module and i strictly followed ur guide, but it doesnt work. The module itself is loading even th icons, but there are no numbers visible. I tried to check the library but it doesnt work.
Is it a Problem on my side or a Problem with the adafruit library?

Thx for your help.

lif

I have installed the module but get the following when I try to run your test ‘python3 AdafruitDHT.py 22 26’

I know the DHT-22 works on GPIO pin 26
~/Adafruit_Python_DHT/examples $ sudo python3 AdafruitDHT.py 22 26
Traceback (most recent call last):
File “/home/pi/Adafruit_Python_DHT/examples/AdafruitDHT.py”, line 41, in
humidity, temperature = Adafruit_DHT.read_retry(sensor, pin)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File “/usr/local/lib/python3.11/dist-packages/Adafruit_DHT-1.4.0-py3.11-linux-aarch64.egg/Adafruit_DHT/common.py”, line 94, in read_retry
humidity, temperature = read(sensor, pin, platform)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File “/usr/local/lib/python3.11/dist-packages/Adafruit_DHT-1.4.0-py3.11-linux-aarch64.egg/Adafruit_DHT/common.py”, line 80, in read
platform = get_platform()
^^^^^^^^^^^^^^
File “/usr/local/lib/python3.11/dist-packages/Adafruit_DHT-1.4.0-py3.11-linux-aarch64.egg/Adafruit_DHT/common.py”, line 63, in get_platform
raise RuntimeError(‘Unknown platform.’)
RuntimeError: Unknown platform.

Any thoughts?

BKeyport

@lif It’s requiring tools no longer available, so dead module. Use something else.

https://github.com/Tom-Hirschberger/MMM-Temperature is what I used when I had a module hooked up to it.

lif

@BKeyport said in MMM-DHT22:

@lif It’s requiring tools no longer available, so dead module. Use something else.

https://github.com/Tom-Hirschberger/MMM-Temperature is what I used when I had a module hooked up to it.

Thanks, I’ve given it a try but get an error in the last stage of the installation

~/MagicMirror/modules/MMM-Temperature/scripts $ ./venvWrapper.py --venv-name py-venv --run ./dht22

Traceback (most recent call last):
  File "/home/pi/MagicMirror/modules/MMM-Temperature/scripts/./dht22", line 6, in <module>
    import board
  File "/home/pi/MagicMirror/modules/MMM-Temperature/scripts/py-venv/lib/python3.11/site-packages/board.py", line 51, in <module>
    from adafruit_blinka.board.raspberrypi.raspi_40pin import *
  File "/home/pi/MagicMirror/modules/MMM-Temperature/scripts/py-venv/lib/python3.11/site-packages/adafruit_blinka/board/raspberrypi/raspi_40pin.py", line 6, in <module>
    from adafruit_blinka.microcontroller.bcm283x import pin
  File "/home/pi/MagicMirror/modules/MMM-Temperature/scripts/py-venv/lib/python3.11/site-packages/adafruit_blinka/microcontroller/bcm283x/pin.py", line 7, in <module>
    from adafruit_blinka.microcontroller.generic_linux.rpi_gpio_pin import Pin
  File "/home/pi/MagicMirror/modules/MMM-Temperature/scripts/py-venv/lib/python3.11/site-packages/adafruit_blinka/microcontroller/generic_linux/rpi_gpio_pin.py", line 6, in <module>
    from RPi import GPIO
ModuleNotFoundError: No module named 'RPi'

BKeyport

@lif I’m not sure on that, @wishmaster270 (Tom) would know more.

lif

Thanks, not the end of the world if I can’t use it.

wishmaster270

@lif Hi. Great you want to try one of my modules.

Can you try installing a additional python system package with

sudo apt install python3-rpi-lgpio

I tried the scripts on my newly installed system with Bookworm and everything worked as expected.
Maybe the missing package had been installed with something else I installed on my system.

lif

@wishmaster270 said in MMM-DHT22:

@lif Hi. Great you want to try one of my modules.

Can you try installing a additional python system package with
sudo apt install python3-rpi-lgpio
I tried the scripts on my newly installed system with Bookworm and everything worked as expected.
Maybe the missing package had been installed with something else I installed on my system.

Thanks, that was already installed

sudo apt install python3-rpi-lgpio
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
python3-rpi-lgpio is already the newest version (0.6-0~rpt1).
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.

This is on Bookworm

wishmaster270

@lif
That’s strange…Can you try to start with a new, fresh virtual python environment and install the needed libs again?

Remove old virtual environment:

rm -rf /home/pi/MagicMirror/modules/MMM-Temperature/scripts/py-venv

Install the needed system libs:

sudo apt -y update && sudo apt -y install python3-venv libgpiod2

Re-Create the virtual environment:

cd ~/MagicMirror/modules/MMM-Temperature/scripts
./venvWrapper.py --verbose --venv-name py-venv --create

Re-Install the libs:

cd ~/MagicMirror/modules/MMM-Temperature/scripts
./venvWrapper.py --venv-name py-venv --install-libs adafruit-circuitpython-dht

Run the test again:

cd ~/MagicMirror/modules/MMM-Temperature/scripts
./venvWrapper.py --venv-name py-venv --run ./dht22

If it fails again. Can you please provide the output of

cd ~/MagicMirror/modules/MMM-Temperature/scripts
source py-venv/bin/activate
pip freeze
deactivate

The output should look something like:

Adafruit-Blinka==8.66.1
Adafruit-Blinka-Raspberry-Pi5-Neopixel==1.0.0rc2
adafruit-circuitpython-busdevice==5.2.13
adafruit-circuitpython-connectionmanager==3.1.5
adafruit-circuitpython-dht==4.0.9
adafruit-circuitpython-requests==4.1.13
adafruit-circuitpython-typing==1.12.2
Adafruit-PlatformDetect==3.83.2
Adafruit-PureIO==1.1.11
binho-host-adapter==0.1.6
lgpio==0.2.2.0
pyftdi==0.57.1
pyserial==3.5
pyusb==1.3.1
rpi-ws281x==5.0.0
RPi.GPIO==0.7.1
sysv-ipc==1.1.0
typing_extensions==4.15.0

sdetweil

@wishmaster270 AND you must enable the virtual env in the script if pm2 starts MagicMirror

wishmaster270

@sdetweil Hi sam. My wrapper script will use the python binary in the virtual environment folder. This way the environment will be activated automatically.

sdetweil

@wishmaster270 cool, you have the venv in the module folder

lif

@wishmaster270 said in MMM-DHT22:

source py-venv/bin/activate

Same failure on install.

from RPi import GPIO
ModuleNotFoundError: No module named 'RPi'
```, 

The output of pip freeze is ```
MagicMirror/modules/MMM-Temperature/scripts $ source py-venv/bin/activate
(py-venv) pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $ pip freeze
Adafruit-Blinka==8.66.2
adafruit-circuitpython-busdevice==5.2.13
adafruit-circuitpython-connectionmanager==3.1.5
adafruit-circuitpython-dht==4.0.9
adafruit-circuitpython-requests==4.1.13
adafruit-circuitpython-typing==1.12.2
Adafruit-PlatformDetect==3.84.0
Adafruit-PureIO==1.1.11
binho-host-adapter==0.1.6
pyftdi==0.57.1
pyserial==3.5
pyusb==1.3.1
sysv-ipc==1.1.0
typing_extensions==4.15.0
(py-venv) pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $ deactivate
pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $

The only difference from yours is mine is missing the second line.

Hope this helps

lif

Hi,

I’ve gone through your procedure again and this time it works.

The only difference is that I run a python3 script to control screen blanking using a PIR before starting Magic Mirror, this time I didn’t start that script.

With the PIR script and MagicMirror running I get:

pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $ ./venvWrapper.py --venv-name py-venv --run ./dht22
{"temperature_c": 23.5, "humidity": 53.7, "temperature_f": 74.30000000000001, "error": false}
pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $ ./venvWrapper.py --venv-name py-venv --run ./dht22
{"temperature_c": 23.5, "humidity": 53.7, "temperature_f": 74.30000000000001, "error": false}
pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $ ./venvWrapper.py --venv-name py-venv --run ./dht22
{"temperature_c": 0.0, "humidity": 0.0, "temperature_f": 32.0, "error": true}
pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $ ./venvWrapper.py --venv-name py-venv --run ./dht22
{"temperature_c": 23.6, "humidity": 53.5, "temperature_f": 74.48, "error": false}
pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $ ./venvWrapper.py --venv-name py-venv --run ./dht22
{"temperature_c": 0.0, "humidity": 0.0, "temperature_f": 32.0, "error": true}
pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $ ./venvWrapper.py --venv-name py-venv --run ./dht22
{"temperature_c": 23.7, "humidity": 53.3, "temperature_f": 74.66, "error": false}
pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $ ./venvWrapper.py --venv-name py-venv --run ./dht22
{"temperature_c": 23.8, "humidity": 53.2, "temperature_f": 74.84, "error": false}
pi@mm:~/MagicMirror/modules/MMM-Temperature/scripts $

I can live with that.

Thanks for all your help