Problem DHT on grovepi+

Archives GrovePi
1

hello,
My grovepi+ is connected on a raspberry 3B+. By testing, I can use every output (like, switch on a led, or make noise with buzzer), but I can’t recover any information from the blue DHT (temperature and humidity), or from the air quality sensor.
My version of OS is : 2019_12_12_Raspbian_For_Robots_Buster_experimental_by_Dexter_Industries.img
The “test and troubleshoot” can’t finish with : “checking for firmware version”.
What can I do ? thank you
jerome

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2

Can you share some code examples?

3

First of all, thank you for your message.
For instance this next code does not send back any error, but … nothing is printing :

import grovepi
import math
import time
# Connect the Grove Temperature & Humidity Sensor Pro to digital port D4
# This example uses the blue colored sensor.
# SIG,NC,VCC,GND
sensor = 4  # The Sensor goes on digital port 4.

# temp_humidity_sensor_type
# Grove Base Kit comes with the blue sensor.
blue = 0    # The Blue colored sensor.
white = 1   # The White colored sensor.

while True:
    try:
        # This example uses the blue colored sensor. 
        # The first parameter is the port, the second parameter is the type of sensor.
        [temp,humidity] = grovepi.dht(sensor,blue)  
        if math.isnan(temp) == False and math.isnan(humidity) == False:
            print("temp = %.02f C humidity =%.02f%%"%(temp, humidity))
        else:
            print("nan values")
        time.sleep(0.5)

    except IOError:
        print ("Error")
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4

You’re on a Pi running Dexter software, right?

Try opening it in Thonny and debugging it.  You will be able to step through the code and see what’s happening.

I don’t see anything obvious. . .

5

Yes, I’ve tried that : with Thonny, the debugger stops when it meets the function ```
grovepi.dht

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6

So, I think that this function does not exist in the module grovepi …

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7

Hello,
I’ve updated with below, and it seems ok !

Thank you for your messages nevertheless

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8

Making sure the firmware is up-to-date is always a good first-step when troubleshooting issues that seem to be board functionality related.

Good find!  Thanks for sharing.