DHT22 duo example doesn't read data from sensor


I have installed Ubuntu on a SD card and all necessary in order to be able to compile the code directly on the duo board.

I have compiled the provided DHT22 duo-example code and let it run. The only output I have is:
“Data not good, skip”

I have tested the sensor with Arduino nano board and it’s working fine.

I do not know what else to do…

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Are voltages and pull-ups on the bus right?

I’m powering the sensor with 3.3V and I have a pull-up resistor of 10K. I have checked with 1K, with 4.7K, but the same result. I have also used a bi-directional logic level converter 5V to 3.3V in order to power the sensor with 5V but to deliver 3.3V to the duo GPIO board, with the same result…

Edit (26.01.2024):

The problem was that I wasn’t grounded the board with the sensor power supply ground…


Glad you have it sorted. A Common Ground between the Duo, and breadboard/sensor is critical for all operations. I have a data-logger that uses the DHT22 to log temp/humidity every 60 seconds to a csv logfile with timestamp in /mnt/log/dht22.log I found using pselect() provides a perfect blocking wait between writes.

The Duo doesn’t implement epoll() in busybox, but since you have Ubuntu, that may also be an option. Good luck with your coding!