Helpdesk

First of all, I bought the Joy-Pi-Note a couple of weeks ago now and I realized that a lot of things didn't quite match with the paper manual and the manuals on the website but ok I managed that, despite that I'm satisfied about the Joy-Pi and enjoying it.[nbsp] Currently I'm going thru lesson 17 Using the DHT sensor and put the python code in accordingly. After the run command I got an error that it couldn't find adafruit_dht in the library so I installed it and run it again which results in the error 'DHT sensor not found, check wiring'. Note: in the beginning of the lesson I already saw that the picture of the sensor didn't match with the one on the board. After the errors I realized that the sensor on the board is the DHT20 address 0x38 doesn't work on adafruit_dht neither with adafruit_circuitpython_dht as they only recognize dht11 and dht22.[nbsp] [nbsp]After searching for solutions on the net I found something on Github, the DHT20 is using DFRobot_DHT20 and[nbsp] smbus2 and after installing them in the library and put them in the import code it was working well.[nbsp] So if anyone experiencing the same problem this is the solution.[nbsp]

I will proceed with the lessons and i will report if these kind of issues appears again.[nbsp][nbsp]

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Regards

Eddy

Hello Eddy,

you are right. Due to component shortage in the past we changed from the DHT11 to the DHT20 on the Joy-Pi Note. But our software differentiates between the two sensors. In the case that your Joy-Pi has a DHT20, the lesson adjusts accordingly and uses the Adafruit AHTX0 library instead.[nbsp]

Are you using the newest version of our software?

Regarding the manual: Can you tell me what exactly did not match? We are of course very happy to adapt our manual if there are any problems here. 🙂

Best regards,
Jens

Hi Jens,

Thanks for reply, as you can see in the header of this messages version 2.0.0 has been installed (was already installed at initial setup) and when I'm running the update function from the menu, it says you have already the newest software installed. So from my opinion I should have the latest learning software. In lesson 17 there is nothing mentioned about Adafruit AHTXo library, but I will try to search for it on the net and try it out.

What I also noticed is that, specially the codes which are using the RGB matrix, don't run on Thonny, you have to use the terminal mode.[nbsp]

Regarding the manual(s) in the hardware part only a minor thing as the USB power cable to connect to the Rasberry Pi was not there and the HDMI connection was a bit confusing as there was already a micro HDMI connector with flatcable there and a normal one in the box. Regarding the software part in the manual(s) its completely different, according to the manual the initial start should come up with the learning screen in German, in my case it started with a desktop screen in English, which was ofcourse much better for me (although Dutch, my German is not so well) but then, as a new Raspberry user, the fun started to find out how everything worked and how to start the lessons for example, how to connect to the internet, bluetooth etc. Well I can tell you a few days later I learned a lot just by trial an error.

Don't see this as criticism but my advice is (specially for newbees) to update the manual and at least explain what's in the menu, Icons, how to connect to WIFI or LAN, bluetooth etc.
To learn more about Python itself I expected a course on the Joy-Pi note, but apparently its not included, no problem I think I will buy a good course book, maybe you can recommend me one, I have quite some experience with Visual Basic.

Thanks
Eddy

Hello Eddy,

don't worry, I don't see that as criticism. Your advice is very welcome and we will happily implement your suggestion.

Regarding your issue in the software: The software does not seem to be in the mode for the newer Joy-Pi versions. To fix that, I would recommend you to reinstall the software.

The issue with Thonny and the RGB matrix is, unfortunately, a well known issue. The library for the RGB matrix needs administrator privileges to execute properly.

If you start Thonny by writing

sudo Thonny

in a terminal, Thonny will execute with the apropriate privileges and the matrix should work well.

If you have any further issues or recommendations, please do not hesitate to write again. 🙂

Best regards
Jens

Hi Jens,

I reinstalled the software and indeed things changed, talking about lesson 17 again, the text has changed as it's talking about DHT20 and adafruit_ahtx0, but the sript is still the old one and still not working ofcourse because DHT20 is using I2C. So I rewrote the script to the one below and that one is working.

import RPi.GPIO as GPIO

import time

import adafruit_character_lcd.character_lcd_i2c as LCD

import board

import adafruit_ahtx0



# Create object for LCD

i2c = board.I2C()

lcd = LCD.Character_LCD_I2C(i2c, 16, 2, address=0x21)





# Create object for DHT20

sensor=adafruit_ahtx0.AHTx0(board.I2C())



# Initialize GPIO

GPIO.setwarnings(False)

GPIO.setmode(GPIO.BCM)



# Read temperature and humidity

temperature = sensor.temperature

humidity = sensor.relative_humidity



# Output data to LCD

lcd.message = 'Temp. = {0:0.1f} *C\nHum. = {1:0.1f} %\n'.format(temperature,humidity)



time.sleep(5)



lcd.clear()

lcd.backlight = False

[nbsp]

Thanks
Eddy

Hi Eddy,

thank you for your feedback. We will check on that issue in detail!

Best regards
Jens