interfacing DHT22 sensor with stm32f411re

[Reva1605]

I am trying to interface DHT22 sensor with STM32F411RE board. When initially I interfaced I was able to see data (i.e., Temp and Humidity) I am giving 3.3v power supply, data pin connected to PA0 ground and set clock frequency to 50MHZ using Internal oscillator. But when now I am trying to check values, I am not able to get values I haven't change anything in code still I am facing this issue. The code is stuck in while loop of DHT22_response function where it is waiting for pin to be low. I have attached coding file please can anyone help me regarding this??

[STackPointer64]

Hello @Reva1605,

Have you tried connecting a pull-up resistor to the data line? Without it, the DHT11 may not be able to pull the line HIGH.

Best regards,

[Reva1605]

Yes tried connecting pull-up resistor of value 4.7k still not working

[STackPointer64]

So, to understand correctly, you created a project and added the functions to interface with the DHT22 sensor. Initially, it worked, but after rebuilding and testing the project again, it got stuck in the DHT22_response function? Have you tried supplying 5V to the sensor or using a different GPIO pin instead of the wakeup pin PA0?

[Andrew Neil]

Welcome to the forum.

Please see How to write your question to maximize your chances to find a solution for best results.

In particular, please describe:

• What board you are using
• Show schematic of how the DHT22 is connected
• Show some good, clear photos of your setup
• Describe what testing/investigation/debugging you've done so far;
  eg, have you looked at the signal line on an oscilloscope?