DHT22 and PCF8575

[deryt]

Hello. On pin P1 I attach the DAT from the sensor DHT22
How do I get the temperature?

[Renzo Mischianti]

Hi deryt,
you must follow the datasheet for communication protocol.
And add an interrupt to the pcf8575 to retrieve all data.

Bye Renzo

[deryt]

I connected directly to the nodemcu, but I can’t connect to the PCF8575 port expander

[Renzo Mischianti]

Hi deryl,
you can follow 2 ways to put in work (and there is a risk that pcf8575 is too slow for the DHT22).
You rewrite the DHT library to use pcf8575 or you implement the DHT22 communication protocol over pcf8575.
Bye Renzo

[Author]

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