Just a few days ago I replaced the firmware on my Sonoff, and immediately after, I wanted more…
After looking on their website, I found a version which also had a DHT11 sensor attached, and I then wanted to do something similar, just with a DHT22 for higher resolution (0.1C on a DHT22, compared to 1C on a DHT11). After digging a bit more in the schematic for the Sonoff, I found that the last pin on the 1×5 pinheader, was connected to GPIO14, so it should not be that difficult to get up and running.
More details at captain-slow.dk
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