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Comment on RPi Pico "disconnects" after a few minutes to days

Do you have a pull up on the DHT20? If not that could explain the reliability issues. 4.7k is needed according to the datasheet.

Not too familiar with the RPi Pico but you might need to disable the internal pull ups if you do that but they are likely too weak so I wouldn’t rely on them.

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agressivelyPassive@feddit.de ⁨1⁩ ⁨year⁩ ago
I looked it up here: aqicn.org/air/sensor/spec/asair-dht20.pdf (I guess that’s the same datasheet you used)

There it says:

To avoid signal conflicts, the microprocessor (MCU) must only drive SDA and SCL at low level. An external pull-up resistor (for example: 4.7kΩ) is required to pull the signal to a high level. The pull-up resistor has been included in the I/O circuit of the DHT20 microprocessor.

This sounds to me like it’s already present in the package? I also haven’t seen any tutorial using any resistors (though that may be just an “error” made by all of them to keep it simple).

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- JoCrichton@lemmy.world ⁨1⁩ ⁨year⁩ ago
  Yeah on that specific board it looks like it’s included . I was just going from experience. I just wired such a sensor to an Arduino the other day and I was having problems without the pull up. I was seeing garbled data packets on the data line.
  
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